BMJ Open HEPATOTOXICITY OF ISOTRETINOIN IN PATIENTS WITH ACNE AND GILBERT'S SYNDROME

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HEPATOTOXICITY OF ISOTRETINOIN IN PATIENTS WITH ACNE AND GILBERT'S SYNDROME Journal: BMJ Open Manuscript ID: bmjopen-0-00 Article Type: Research Date Submitted by the Author: -Nov-0 Complete List of Authors: Fernández-Crehuet, Pablo; Alto Guadalquivir Hospital, Dermatology Unit Serrano, José Luis; Alto Guadalquivir Hospital, Dermatology Unit Allam, Moahmed; Faculty of Medicine, University of Cordoba, Department of Preventive Medicine and Public Health Navajas, Rafael; Faculty of Medicine, University of Cordoba, Department of Preventive Medicine and Public Health <b>primary Subject Heading</b>: Secondary Subject Heading: Keywords: Gastroenterology and hepatology Dermatology, Gastroenterology and hepatology, Pharmacology and therapeutics Acne < DERMATOLOGY, Lipid disorders < DIABETES & ENDOCRINOLOGY, Adult gastroenterology < GASTROENTEROLOGY, Hepatobiliary disease < GASTROENTEROLOGY, Hepatology < INTERNAL MEDICINE BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 HEPATOTOXICITY OF ISOTRETINOIN IN PATIENTS WITH ACNE AND GILBERT'S SYNDROME Pablo Fernández-Crehuet Serrano. MD, PhD José Luis Fernández-Crehuet Serrano. MD, PhD Mohamed Farouk Allam. MPH, PhD Rafael Fernández-Crehuet Navajas. MD, Ph D. Dermatology Unit. Alto Guadalquivir Hospital. Andújar, Jaén, Spain.. Department of Preventive Medicine and Public Health. University of Cordoba, Spain. Correspondence: Mohamed Farouk Allam, Department of Preventive Medicine and Public Health, Faculty of Medicine, University of Cordoba. Avda. Menéndez Pidal, s/n Cordoba 00, Spain. Phone: + ; Fax. + E-mail: fmfaahm@uco.es Word count: Short Title: Hepatotoxicity of isotretinoin in patients with Gilbert's syndrome. Keywords: Acne, bilirubin, Gilbert s syndrome, triglycerides, isotretinoin. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 ABSTRACT Objectives. The objective of our follow-up study is to evaluate liver function tests (LFTs) and lipid profiles in patients with Gilbert s syndrome treated with isotretinoin because of severe acne. Setting. Dermatology Outpatient Clinics of regional hospitals of Jaen (Spain). Participants. All patients with severe acne who attended the Dermatology Outpatient Clinics over years were eligible to be included in our study. We identified patients with severe acne during the study period, of which had Gilbert s syndrome. Interventions. All patients were treated with isotretinoin and followed-up in our outpatient clinics after 0 and 0. Patients were subjected to an interview questionnaire which included data on age, gender, complete blood count, coagulation profile, fasting blood glucose, LFTs and lipid profiles. Primary outcome. Blood analyses were repeated in the follow-up visits. Results. In Gilbert s syndrome patients, bilirubin levels showed substantial decrease over the 0 follow-up, with more decrease after 0. None of the control group patients had significant increase in total bilirubin levels after 0 and 0 follow up. Liver enzymes were maintained within normal levels in both groups. Both studied groups did not show significant pathological increase in lipid profile levels. LDL levels were increased in the studied groups, but this increase was less substantial in Gilbert s syndrome patients. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 Conclusion. Oral isotretinoin is not only an effective safe treatment for patients with Gilbert s syndrome, but also it lowers bilirubin levels in the first 0 of treatment. Ethical Committee: Study approved by the Ethical Committee of Hospital de Andjuar. Article summary 'Strengths and limitations of this study' - All patients with severe acne who attended the Dermatology Outpatient Clinics over years were eligible to be included in our study. - We identified patients with severe acne during the study period, of which had Gilbert s syndrome. Patients were treated with isotretinoin and followed-up in our outpatient clinics after 0 and 0. - Patients were subjected to an interview questionnaire which included data on age, gender, complete blood count, coagulation profile, fasting blood glucose, LFTs and lipid profiles. Blood analyses were repeated in the follow-up visits. - Oral isotretinoin was not only an effective safe treatment for patients with Gilbert s syndrome, but also it lowers bilirubin levels in the first 0 of treatment. - Lipid profile levels in Gilbert s syndrome patients were maintained within the normal recommended levels. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 INTRODUCTION The use of isotretinoin for the treatment of severe acne has been widely used over the last 0 years. Many adverse reactions to iostretinoin have been reported. Several studies BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 have shown that hepatoxicity could occur in about 0% and hyperlipidemia in 0- %.[-] Gilbert s syndrome is a benign and inherited state characterized by intermittent unconjugated hyperbilirubinaemia with accompanying jaundice in the absence of haemolysis or underlying liver disease.[] Previous studies have shown that Gilbert's syndrome affects % to % of the population, mainly postpubertal male patients.[-] In patients with hepatic dysfunction, like Gilbert s syndrome, we would expect an increased sensitivity to isotretinoin that is metabolized by hepatic oxidation and biliary excretion.[-] The objective of our follow-up study is to evaluate liver function tests (LFTs) and lipid profiles in patients with Gilbert s syndrome treated with isotretinoin because of severe acne. METHODOLOGY All patients with severe acne who attended the Dermatology Outpatient Clinics of the regional hospitals of Andujar, Alcala la Real and Alcaudete (Jaen, Spain) over years were eligible to be included in our study. Owning to the location of these regional hospitals in the centre of Andalusia, they serve over one million persons. Only patients with severe acne and treated with isotretinoin from September, 00 to August, 0 were included consecutively in the study. Inclusion criteria were age between and 0 years old, severe acne, treatment with oral isotretinoin (0.-0. mg/kg) and normal LFTs and lipid profiles. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 Meanwhile, exclusion criteria were contradictions for isotretinoin, concomitant use before or during the study of other treatment inducer of Cytochrome P0, alcohol consumption, significant change in weight (>0%) and suspension of the treatment. We identified patients with severe acne during the study period, of which had Gilbert s syndrome. All patients were informed about the aim of the study and signed an informed consent. Patients were subjected to an interview questionnaire which included data on age, gender, complete blood count, coagulation profile, fasting blood glucose, liver function tests and lipid profiles. Basal levels of bilirubin in patients with Gilbert s syndrome were measured in consecutive mornings. Of the measures, the mean basal level was calculated. Fasting levels of bilirubin in patients with Gilbert s syndrome were >. mg/dl. All patients were followed up in our outpatient clinics after 0 and 0. Blood analyses were repeated in the follow-up visits. No adverse effects of isotretinoin treatment were noted and in all patients the acne was in complete remission at the last follow-up visit. Statistical methods: First, the following descriptive analysis was done: frequency, percent, mean, standard deviation. Comparisons between patients with Gilbert s syndrome and control patients were done using Mann-Whitney test for continuous variables and Pearson s Chi square test for categorical variables. Comparisons of LFTs and lipid profile levels over the follow-up period were done using Friedman Test. Level of significance was set at p BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 <0.0. All data variables were encoded and computerized. Data entry and statistical analysis were performed using the Statistical Package for Social Science (SPSS) version.0 (SPSS Inc., Chicago, Illinois). RESULTS Our follow-up study included patients with severe acne; patients with Gilbert s syndrome and control patients. No statistical significant differences were found between the studied groups regarding age and gender. In Gilbert s syndrome patients, bilirubin levels showed substantial decrease over the 0 follow-up, with more decrease after 0 compared with the basal level (P value <0.00). Meanwhile, AST, ALT and GGT levels over the 0 follow-up did not vary significantly; P values 0., 0. and 0. respectively (Table ). In control patients, bilirubin and ALT levels did not vary significantly over the 0 follow-up; P value 0. and 0. respectively. Meanwhile, AST and GGT varied significantly over the 0 follow-up; P value 0.0 and 0.00 respectively (Table ). In Gilbert s syndrome patients, LDL levels showed substantial increase over the 0 follow-up, with more increase after 0 compared with the basal level (P value <0.00). Meanwhile, cholesterol, triglycerides and HDL levels over the 0 follow-up did not vary significantly; P values 0., 0. and 0. respectively (Table ). In control patients, cholesterol, triglycerides and LDL levels showed substantial increase over the 0 follow-up; P values <0.00. Meanwhile, HDL levels over the 0 follow up did not vary significantly; P values 0. (Table ). BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 DISCUSSION The main objective of the current follow-up study was to evaluate the hepatotoxicity of isotretinoin in patients with Gilbert s syndrome. In theory, hepatotoxic drugs like isotretinoin would increase bilirubin and liver enzymes levels in patients with hereditary hepatic disorders like Gilbert s syndrome.[] Before reaching conclusions based on the present results, it is necessary to consider a number of potential objections to the methodology. Limitations such as the small sample size could affect the validity of the results. Our study included only patients with severe acne and treated with oral isotretinoin. It was difficult to identify more patients according to our strict inclusion and exclusion criteria, and that is why we included all patients treated over years in regional hospitals. Other possible limitations were the placebo effect and the natural evolution. Placebo effect was avoided by repeated measures; before and 0 and 0 after treatment. Natural evolution was controlled be the follow-up comparative control group without Gilbert s syndrome. By 0 all patients with Gilbert s syndrome had a significant decrease in total bilirubin levels and they maintained this decrease after 0. The cause for decline in bilirubin levels in patients with Gilbert s syndrome treated with isotretinoin is still unknown. Only few studies were published about this unexpected decline in bilirubin levels by a hepatotoxic drug like isotretinoin.[-0] Several drugs like phenobarbitals and corticosteroids induce microsomal enzymes as UDP-GT and stimulate the conjugation of bilirubin producing its decrease. In contrary, BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 isotretinoin inhibits the inducer effect of other drugs and thus this does not seems to be its mechanism of action in patients with Gilbert s syndrome.[-] Currently, there two hypothesis to explain this strange effect of isotretinoin in patients with Gilbert s syndrome; reversible decrease in the serum levels of testosterone increasing the activity of UDP-GT or stimulating hepatocytes to generate transporting proteins that eliminate bilirubin.[-] None of the control group patients had significant increase in total bilirubin levels after 0 and 0 follow-up. Of note, liver enzymes (AST, ALT and GGT) were maintained within normal levels in both studied groups. Our study also explored the adverse effect of isotretinoin on lipid profile levels. Both studied groups did not show significant pathological increase in lipid profile levels (cholesterol, triglycerides, HDL and LDL). All lipid profile levels in Gilbert s syndrome patients and control patients were maintained within the normal recommended levels. Recent follow-up study with patients treated with isotretinoin because of acne vulgaris, showed that only.% suffered impaired LFTs and.% had high lipid profile levels after of treatment.[] These findings agree with our results after 0 and 0 of follow-up in both Gilbert s syndrome and control patients. LDL levels were increased in the studied groups, but this increase was less substantial in Gilbert s syndrome patients. Again, these findings are contradictory to what would be expected from hepatotoxic drug administrated in patients with hepatic dysfunction. Previous studies showed that patients with Gilbert s syndrome have lower prevalence of atherosclerosis and ischemic heart disease.[-] A systematic review confirmed that BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page 0 of 0 0 0 0 0 0 there is a reliable inverse and dose response relationship between serum bilirubin and the atherosclerotic process.[] Recent case control study showed that LDL, well known mediator of initial stages of atherosclerosis, was lower in patients with Gilbert s syndrome when compared to healthy controls.[] This agrees with the results of our study where basal levels of LDL and after isotretinoin treatment were lower in patients with Gilbert s syndrome compared with control patients. In conclusion, oral isotretinoin is not only an effective safe treatment for patients with Gilbert s syndrome, but also it lowers bilirubin levels in the first 0 of treatment. Identification of the mechanism of action of oral isotretinoin in patients with Gilbert s syndrome could help in elaborating new protective drugs against hepatotoxicity. 0 BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 CONTRIBUTORSHIP STATEMENT: Each author declares having participated in the activities described below and that they have seen and approved the final version. They also declare not having conflict of interest in connection with this paper, other than any noted in the covering letter to the editor. Pablo Fernández-Crehuet Serrano: Field work supervision, analysis strategy and design, data management, data analysis and interpretation of results, decision making on content and paper write-up and revision of final draft. José Luis Fernández-Crehuet Serrano: Field work supervision, analysis strategy and design, data management, data analysis and interpretation of results, decision making on content and paper write-up and revision of final draft. Mohamed Farouk Allam: Data analysis, interpretation of results, decision making on content and paper write-up and revision of final draft. Rafael Fernández-Crehuet Navajas: Author of original idea, study design, field work supervision, data analysis, decision making on content and paper write-up and revision of final draft. Funding: none. Conflicts of interest: none. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 REFERENCES. Marsden JR, Trinick TR, Laker MF, et al. Effects of isotretinoin on serum lipids and lipoproteins, liver and thyroid function. Clin Chim Acta ;():-.. Vieria AS, Bejamini V, Melchiors AC. The effect of isotretinoin on triglycerides and liver aminotransferases. An Bras Dermatol 0;():-.. Schmitt JV, Tavares M, Cerci FB. Adult women with acne have a higher risk of elevated triglyceride levels with the use of oral isotretinoin. [Article in English, Portuguese] An Bras Dermatol 0;():0-0. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0. Gilbert syndrome. American Liver Foundation website. Available at: http://www.liverfoundation.org/abouttheliver/info/gilbertsyndrome/. Accessed June, 0.. Dicken CH. Retinoids: a review. J Am Acad Dernatol ;( Pt ):-.. Grønhøj Larsen F, Jakobsen P, Grønhøj Larsen C, et al. The metabolism and pharmacokinetics of isotretinoin in patients with acne and rosacea are not influenced by ethanol. Br J Dermatol 00;():-0.. Meloche S, Besner JG. Metabolism of isotretinoin. Biliary excretion of isotretinoin glucuronide in the rat. Drug Metab Dispos ;():-.. Wang JI, Jackson TL Jr, Kaplan DL. Isotretinoin-associated normalization of hyperbilirubinemia in patients with Gilbert's syndrome. J Am Acad Dermatol ;:-.. Le Gal FA, Pauwels C. Gilbert disease and isotretinoin. Ann Dermatol Venereol ;:-. 0. Black M, Sherlock S. Treatment of Gilbert's syndrome with phenobarbitone. Lancet 0;:-.. Shah IA, Whiting PH, Omar G, et al. The effects of retinoids and terbinafine on the human hepatic microsomal metabolism of cyclosporin. Br J Dermatol ;:-.. Rademaker M, Wallace M, Cunliffe W, et al. Isotretinoin treatment alters steroid metabolism in women with acne. Br J Dermatol ;:-.. Goodman DS. Vitamin A and retinoids in health and disease. N Engl J Med ;0:0-. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0. Bruno NP, Beacham BE, Burnett JW. Adverse effects of isotretinoin therapy. Cutis ;:-.. Muhammad Tahir Ch. Efficacy and adverse effects of systemic isotretinoin therapy. J Pak Assoc Dermatol 0;:-.. Vitek L, Jirsa M, Brodanova M, et al. Gilbert syndrome and ischemic heart disease: a protective effect of elevated bilirubin levels. Atherosclerosis 00;0:-.. Schwertner HA. Bilirubin concentration, UGTA* polymorphism, and coronary artery disease. Clin Chem 00;:0-0.. Novotny L, Vitek L. Inverse relationship between serum bilirubin and atherosclerosis in men: a meta-analysis of published studies. Exp Biol Med (Maywood) 00;:-.. Tapan S, Karadurmus N, Dogru T, et al. Decreased small dense LDL levels in Gilbert's syndrome. Clin Biochme 0;():00-. Table. Follow-up and comparative study of liver function tests in controls and patients with Gilbert s syndrome treated with isotretinoin. Case/Variable Gilbert s Syndrome Control P value Basal bilirubin. ± 0. 0.0 ± 0. <0.00 levels Bilirubin levels.0 ± 0. 0. ± 0. <0.00 after 0 Bilirubin levels. ± 0. 0. ± 0. <0.00 after 0 Basal AST levels. ±.. ±. 0. AST levels after 0 AST levels after 0. ±.. ±. 0.. ±.. ±. 0. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 Basal ALT levels 0 ± 0.. ±.0 0. ALT levels after 0. ±.. ±. <0.0 ALT levels after 0. ±.. ±. 0. Basal GGT levels. ±. ±. 0. GGT levels after 0 ±.. ±. 0. GGT levels after 0. ±.. ±. 0. Mann-Whitney Test Table. Follow-up and comparative study of lipid profile in controls and patients with Gilbert s syndrome treated with isotretinoin. Case/Variable Gilbert s Syndrome Control P value Basal cholesterol levels Cholesterol levels after 0 Cholesterol levels after 0 Basal triglycerides levels Triglycerides levels after 0 Triglycerides levels after 0. ±.. ±. 0.0. ±.. ± 0 0.. ±.. ± 0. 0.. ±.. ± 0.. ± 0.. ±. 0.. ± 0. ±. <0.0 BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 Basal HDL levels. ±.. ±. 0. HDL levels after 0. ±.. ±. 0. HDL levels after 0. ±.. ±. 0. Basal LDL levels. ±.. ± 0. 0. LDL levels after 0. ±. ±. 0. LDL levels after 0. ±. 0. ±. <0.0 Mann-Whitney Test BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 STROBE Statement checklist of items that should be included in reports of observational studies Item No Recommendation Title and abstract (a) Indicate the study s design with a commonly used term in the title or the abstract Introduction (b) Provide in the abstract an informative and balanced summary of what was done and what was found Background/rationale Explain the scientific background and rationale for the investigation being reported Objectives State specific objectives, including any prespecified hypotheses Methods Study design Present key elements of study design early in the paper Setting Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data collection Participants (a) Cohort study Give the eligibility criteria, and the sources and methods of selection of participants. Describe methods of follow-up Case-control study Give the eligibility criteria, and the sources and methods of case ascertainment and control selection. Give the rationale for the choice of cases and controls Cross-sectional study Give the eligibility criteria, and the sources and methods of selection of participants (b) Cohort study For matched studies, give matching criteria and number of exposed and unexposed Case-control study For matched studies, give matching criteria and the number of controls per case Variables Clearly define all outcomes, exposures, predictors, potential confounders, and effect Data sources/ measurement modifiers. Give diagnostic criteria, if applicable * For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe comparability of assessment methods if there is more than one group Bias Describe any efforts to address potential sources of bias Study size 0 Explain how the study size was arrived at Quantitative variables Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and why Statistical methods (a) Describe all statistical methods, including those used to control for confounding Continued on next page (b) Describe any methods used to examine subgroups and interactions (c) Explain how missing data were addressed (d) Cohort study If applicable, explain how loss to follow-up was addressed Case-control study If applicable, explain how matching of cases and controls was addressed Cross-sectional study If applicable, describe analytical methods taking account of sampling strategy (e) Describe any sensitivity analyses BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 Results Participants * (a) Report numbers of individuals at each stage of study eg numbers potentially eligible, examined for eligibility, confirmed eligible, included in the study, completing follow-up, and analysed (b) Give reasons for non-participation at each stage (c) Consider use of a flow diagram Descriptive data * (a) Give characteristics of study participants (eg demographic, clinical, social) and information on exposures and potential confounders (b) Indicate number of participants with missing data for each variable of interest (c) Cohort study Summarise follow-up time (eg, average and total amount) Outcome data * Cohort study Report numbers of outcome events or summary measures over time Case-control study Report numbers in each exposure category, or summary measures of exposure Cross-sectional study Report numbers of outcome events or summary measures Main results (a) Give unadjusted estimates and, if applicable, confounder-adjusted estimates and their precision (eg, % confidence interval). Make clear which confounders were adjusted for and why they were included (b) Report category boundaries when continuous variables were categorized (c) If relevant, consider translating estimates of relative risk into absolute risk for a meaningful time period Other analyses Report other analyses done eg analyses of subgroups and interactions, and sensitivity analyses Discussion Key results Summarise key results with reference to study objectives Limitations Discuss limitations of the study, taking into account sources of potential bias or imprecision. Discuss both direction and magnitude of any potential bias Interpretation 0 Give a cautious overall interpretation of results considering objectives, limitations, multiplicity of analyses, results from similar studies, and other relevant evidence Generalisability Discuss the generalisability (external validity) of the study results Other information Funding Give the source of funding and the role of the funders for the present study and, if applicable, for the original study on which the present article is based *Give information separately for cases and controls in case-control studies and, if applicable, for exposed and unexposed groups in cohort and cross-sectional studies. Note: An Explanation and Elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting. The STROBE checklist is best used in conjunction with this article (freely available on the Web sites of PLoS Medicine at http://www.plosmedicine.org/, Annals of Internal Medicine at http://www.annals.org/, and Epidemiology at http://www.epidem.com/). Information on the STROBE Initiative is available at www.strobe-statement.org. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

HEPATOTOXICITY OF ISOTRETINOIN IN PATIENTS WITH ACNE AND GILBERT'S SYNDROME: CASE SERIES Journal: BMJ Open Manuscript ID: bmjopen-0-00.r Article Type: Research Date Submitted by the Author: -Feb-0 Complete List of Authors: Fernández-Crehuet, Pablo; Alto Guadalquivir Hospital, Dermatology Unit Serrano, José Luis; Alto Guadalquivir Hospital, Dermatology Unit Allam, Moahmed; Faculty of Medicine, University of Cordoba, Department of Preventive Medicine and Public Health Navajas, Rafael; Faculty of Medicine, University of Cordoba, Department of Preventive Medicine and Public Health <b>primary Subject Heading</b>: Secondary Subject Heading: Keywords: Gastroenterology and hepatology Dermatology, Gastroenterology and hepatology, Pharmacology and therapeutics Acne < DERMATOLOGY, Hepatobiliary disease < GASTROENTEROLOGY, Physiology < BASIC SCIENCES, CLINICAL PHARMACOLOGY, Hepatology < INTERNAL MEDICINE BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 HEPATOTOXICITY OF ISOTRETINOIN IN PATIENTS WITH ACNE AND GILBERT'S SYNDROME: CASE SERIES José Luis Fernández-Crehuet Serrano. MD, PhD Pablo Fernández-Crehuet Serrano. MD, PhD Mohamed Farouk Allam. MPH, PhD Rafael Fernández-Crehuet Navajas. MD, Ph D. Dermatology Unit. Alto Guadalquivir Hospital. Andújar, Jaén, Spain.. Department of Preventive Medicine and Public Health. University of Cordoba, Spain. Correspondence: Mohamed Farouk Allam, Department of Preventive Medicine and Public Health, Faculty of Medicine, University of Cordoba. Avda. Menéndez Pidal, s/n Cordoba 00, Spain. Phone: + ; Fax. + E-mail: fmfaahm@uco.es Word count: Short Title: Hepatotoxicity of isotretinoin in patients with Gilbert's syndrome. ABSTRACT BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 Objectives. The objective of our follow-up study is to evaluate liver function tests (LFTs) and lipid profiles in patients with Gilbert s syndrome treated with isotretinoin because of severe acne. Setting. Dermatology Outpatient Clinics of regional hospitals of Jaen (Spain). Participants. Over years, we included all patients diagnosed with severe acne. Only patients were identified, of which had Gilbert s syndrome. Interventions. All patients were treated with isotretinoin and followed-up in our outpatient clinics after 0 and 0. Patients were subjected to an interview questionnaire which included data on age, gender, complete blood count, coagulation profile, fasting blood glucose, LFTs and lipid profiles. Data and results of patients with severe acne and Gilbert s syndrome were compared with these of the patients with only severe acne (control group). Primary outcome. Blood analyses were repeated in the follow-up visits. Results. In Gilbert s syndrome patients, bilirubin levels showed substantial decrease over the 0 follow-up, with more decrease after 0. None of the control group patients had significant increase in total bilirubin levels after 0 and 0 follow up. Liver enzymes were maintained within normal levels in both groups. Both studied groups did not show significant pathological increase in lipid profile levels. LDL levels were increased in the studied groups, but this increase was less substantial in Gilbert s syndrome patients. Conclusion. Oral isotretinoin is not only an effective safe treatment for patients with Gilbert s syndrome, but also it lowers bilirubin levels in the first 0 of treatment. Limitations of the study include the small numbers of participants and the fact that it is restricted to one region of Spain. Keywords: Acne, bilirubin, Gilbert s syndrome, triglycerides, isotretinoin. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 Ethical Committee: Study approved by the Ethical Committee of Hospital de Andjuar. Article summary 'Strengths and limitations of this study' - All patients with severe acne who attended the Dermatology Outpatient Clinics over years were eligible to be included in our study. - We identified patients with severe acne during the study period, of which had Gilbert s syndrome. Patients were treated with isotretinoin and followed-up in our outpatient clinics after 0 and 0. - Patients were subjected to an interview questionnaire which included data on age, gender, complete blood count, coagulation profile, fasting blood glucose, LFTs and lipid profiles. Blood analyses were repeated in the follow-up visits. - Oral isotretinoin was not only an effective safe treatment for patients with Gilbert s syndrome, but also it lowers bilirubin levels in the first 0 of treatment. - Lipid profile levels in Gilbert s syndrome patients were maintained within the normal recommended levels. - Limitations of the study include the small numbers of participants and the fact that it is restricted to one region of Spain. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 INTRODUCTION The use of isotretinoin for the treatment of severe acne has been widely used over the last 0 years. Many adverse reactions to iostretinoin have been reported. Several studies have shown that hepatoxicity could occur in about 0% and hyperlipidemia in 0- %.[-] Gilbert s syndrome is a benign and inherited state characterized by intermittent unconjugated hyperbilirubinaemia with accompanying jaundice in the absence of haemolysis or underlying liver disease.[] Previous studies have shown that Gilbert's syndrome affects % to % of the population, mainly postpubertal male patients.[-] In patients with hepatic dysfunction, like Gilbert s syndrome, we would expect an increased sensitivity to isotretinoin that is metabolized by hepatic oxidation and biliary excretion.[-] The objective of our follow-up study is to evaluate liver function tests (LFTs) and lipid profiles in patients with Gilbert s syndrome treated with isotretinoin because of severe acne. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 METHODOLOGY All patients with severe acne who attended the Dermatology Outpatient Clinics of the regional hospitals of Andujar, Alcala la Real and Alcaudete (Jaen, Spain) over years were eligible to be included in our study. Owning to the location of these regional hospitals in the centre of Andalusia, they serve over one million persons. Only patients with severe acne and treated with isotretinoin from September, 00 to August, 0 were included consecutively in the study. Severe acne was diagnosed according to the European evidence-based (S) guidelines for the treatment of acne.[] Inclusion criteria were age between and 0 years old, severe acne, treatment with oral isotretinoin (0.-0. mg/kg) and normal LFTs and lipid profiles. Meanwhile, exclusion criteria were contradictions for isotretinoin, concomitant use before or during the study of other treatment inducer of Cytochrome P0, alcohol consumption, significant change in weight (>0%) and suspension of the treatment. We identified patients with severe acne during the study period, of which had Gilbert s syndrome. All patients were informed about the aim of the study and signed an informed consent. Patients were subjected to an interview questionnaire which included data on age, gender, complete blood count, coagulation profile, fasting blood glucose, liver function tests and lipid profiles. All questionnaire data were collected by the first author (P F-C S) in the Dermatology Outpatient Clinics of the regional hospitals of Andujar, Alcala BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 la Real and Alcaudete, and the blood tests were done the laboratories of the same hospitals. Basal levels of bilirubin in patients with Gilbert s syndrome were measured in consecutive mornings. Of the measures, the mean basal level was calculated. Fasting levels of bilirubin in patients with Gilbert s syndrome were >. mg/dl. All patients were followed up in our outpatient clinics after 0 and 0. Blood analyses were repeated in the follow-up visits. All participants were followed up over 0 with no lost follow-up. Data and results of patients with severe acne and Gilbert s syndrome were compared with these of the patients with only severe acne (control group). No adverse effects of isotretinoin treatment were noted and in all patients the acne was in complete remission at the last follow-up visit. Statistical methods: First, the following descriptive analysis was done: frequency, percent, mean, standard deviation. Comparisons between patients with Gilbert s syndrome and control patients were done using Mann-Whitney test for continuous variables and Pearson s Chi square test for categorical variables. Comparisons of LFTs and lipid profile levels over the follow-up period were done using Friedman Test. Level of significance was set at p <0.0. All data variables were encoded and computerized. Data entry and statistical analysis were performed using the Statistical Package for Social Science (SPSS) version.0 (SPSS Inc., Chicago, Illinois). BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 RESULTS Our follow-up study included patients with severe acne; patients with Gilbert s syndrome and control patients. No statistical significant differences were found between the studied groups regarding age and gender. In Gilbert s syndrome patients, bilirubin levels showed substantial decrease over the 0 follow-up, with more decrease after 0 compared with the basal level (P value <0.00). Meanwhile, AST, ALT and GGT levels over the 0 follow-up did not vary significantly; P values 0., 0. and 0. respectively (Table ). In control patients, bilirubin and ALT levels did not vary significantly over the 0 follow-up; P value 0. and 0. respectively. Meanwhile, AST and GGT varied significantly over the 0 follow-up; P value 0.0 and 0.00 respectively (Table ). In Gilbert s syndrome patients, LDL levels showed substantial increase over the 0 follow-up, with more increase after 0 compared with the basal level (P value <0.00). Meanwhile, cholesterol, triglycerides and HDL levels over the 0 follow-up did not vary significantly; P values 0., 0. and 0. respectively (Table ). In control patients, cholesterol, triglycerides and LDL levels showed substantial increase over the 0 follow-up; P values <0.00. Meanwhile, HDL levels over the 0 follow up did not vary significantly; P values 0. (Table ). BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 DISCUSSION The main objective of the current follow-up study was to evaluate the hepatotoxicity of isotretinoin in patients with Gilbert s syndrome. In theory, hepatotoxic drugs like isotretinoin would increase bilirubin and liver enzymes levels in patients with hereditary hepatic disorders like Gilbert s syndrome.[] Before reaching conclusions based on the present results, it is necessary to consider a number of potential objections to the methodology. Limitations such as the small sample size could affect the validity of the results. Our study included only patients with severe acne and treated with oral isotretinoin. It was difficult to identify more patients according to our strict inclusion and exclusion criteria, and that is why we included all patients treated over years in regional hospitals. Other possible limitations were the placebo effect and the natural evolution. Placebo effect was avoided by repeated measures; before and 0 and 0 after treatment. Natural evolution was controlled be the follow-up comparative control group without Gilbert s syndrome. Although these results pertain solely to a region of the province of Jaen (Spain) and should not be considered generalizable, the methodology can be applied in different Dermatology Outpatient Clinics. Our results call for further investigation of hepatotoxicity of isotretinoin in patients with acne and Gilbert's syndrome; future studies preferably should be performed on large prospective cohorts, to increase their internal validity. By 0 all patients with Gilbert s syndrome had a significant decrease in total bilirubin levels and they maintained this decrease after 0. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 The cause for decline in bilirubin levels in patients with Gilbert s syndrome treated with isotretinoin is still unknown. Only few studies were published about this unexpected decline in bilirubin levels by a hepatotoxic drug like isotretinoin.[-] Several drugs like phenobarbitals and corticosteroids induce microsomal enzymes as UDP-GT and stimulate the conjugation of bilirubin producing its decrease. In contrary, isotretinoin inhibits the inducer effect of other drugs and thus this does not seems to be its mechanism of action in patients with Gilbert s syndrome.[-] Currently, there are two hypotheses to explain this unexpected effect of isotretinoin in patients with Gilbert s syndrome; reversible decrease in the serum levels of testosterone increasing the activity of UDP-GT or stimulating hepatocytes to generate transporting proteins that eliminate bilirubin.[-] None of the control group patients had significant increase in total bilirubin levels after 0 and 0 follow-up. Of note, liver enzymes (AST, ALT and GGT) were maintained within normal levels in both studied groups. Our study also explored the adverse effect of isotretinoin on lipid profile levels. Both studied groups did not show significant pathological increase in lipid profile levels (cholesterol, triglycerides, HDL and LDL). All lipid profile levels in Gilbert s syndrome patients and control patients were maintained within the normal recommended levels. Recent follow-up study with patients treated with isotretinoin because of acne vulgaris, showed that only.% suffered impaired LFTs and.% had high lipid profile levels after of treatment.[] These findings agree with our results after 0 and 0 of follow-up in both Gilbert s syndrome and control patients. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page 0 of 0 0 0 0 0 0 LDL levels were increased in the studied groups, but this increase was less substantial in Gilbert s syndrome patients. Again, these findings are contradictory to what would be expected from hepatotoxic drug administrated in patients with hepatic dysfunction. Previous studies showed that patients with Gilbert s syndrome have lower prevalence of atherosclerosis and ischemic heart disease.[-] A systematic review confirmed that there is a reliable inverse and dose response relationship between serum bilirubin and the atherosclerotic process.[] Recent case control study showed that LDL, well known mediator of initial stages of atherosclerosis, was lower in patients with Gilbert s syndrome when compared to healthy controls.[0] This agrees with the results of our study where basal levels of LDL and after isotretinoin treatment were lower in patients with Gilbert s syndrome compared with control patients. In conclusion, our preliminary results show that oral isotretinoin is not only an effective safe treatment for patients with Gilbert s syndrome, but also it lowers bilirubin levels in the first 0 of treatment. Identification of the mechanism of action of oral isotretinoin in patients with Gilbert s syndrome could help in elaborating new protective drugs against hepatotoxicity. 0 BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 CONTRIBUTORSHIP STATEMENT: Each author declares having participated in the activities described below and that they have seen and approved the final version. They also declare not having conflict of interest in connection with this paper, other than any noted in the covering letter to the editor. Pablo Fernández-Crehuet Serrano: Field work supervision, analysis strategy and design, data management, data analysis and interpretation of results, decision making on content and paper write-up and revision of final draft. José Luis Fernández-Crehuet Serrano: Field work supervision, analysis strategy and design, data management, data analysis and interpretation of results, decision making on content and paper write-up and revision of final draft. Mohamed Farouk Allam: Data analysis, interpretation of results, decision making on content and paper write-up and revision of final draft. Rafael Fernández-Crehuet Navajas: Author of original idea, study design, field work supervision, data analysis, decision making on content and paper write-up and revision of final draft. Funding: none. Conflicts of interest: none. Data Sharing Statement: none BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 REFERENCES. Marsden JR, Trinick TR, Laker MF, et al. Effects of isotretinoin on serum lipids and lipoproteins, liver and thyroid function. Clin Chim Acta ;():-.. Vieria AS, Bejamini V, Melchiors AC. The effect of isotretinoin on triglycerides and liver aminotransferases. An Bras Dermatol 0;():-.. Schmitt JV, Tavares M, Cerci FB. Adult women with acne have a higher risk of elevated triglyceride levels with the use of oral isotretinoin. [Article in English, Portuguese] An Bras Dermatol 0;():0-0.. Gilbert syndrome. American Liver Foundation website. Available at: http://www.liverfoundation.org/abouttheliver/info/gilbertsyndrome/. Accessed June, 0.. Dicken CH. Retinoids: a review. J Am Acad Dernatol ;( Pt ):-.. Grønhøj Larsen F, Jakobsen P, Grønhøj Larsen C, et al. The metabolism and pharmacokinetics of isotretinoin in patients with acne and rosacea are not influenced by ethanol. Br J Dermatol 00;():-0.. Meloche S, Besner JG. Metabolism of isotretinoin. Biliary excretion of isotretinoin glucuronide in the rat. Drug Metab Dispos ;():-.. Nast A, Dréno B, Bettoli V, et al. European evidence-based (S) guidelines for the treatment of acne. J Eur Acad Dermatol Venereol 0;(Suppl ):-. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0. Wang JI, Jackson TL Jr, Kaplan DL. Isotretinoin-associated normalization of hyperbilirubinemia in patients with Gilbert's syndrome. J Am Acad Dermatol ;:-. 0. Le Gal FA, Pauwels C. Gilbert disease and isotretinoin. Ann Dermatol Venereol ;:-.. Black M, Sherlock S. Treatment of Gilbert's syndrome with phenobarbitone. Lancet 0;:-.. Shah IA, Whiting PH, Omar G, et al. The effects of retinoids and terbinafine on the human hepatic microsomal metabolism of cyclosporin. Br J Dermatol ;:-.. Rademaker M, Wallace M, Cunliffe W, et al. Isotretinoin treatment alters steroid metabolism in women with acne. Br J Dermatol ;:-.. Goodman DS. Vitamin A and retinoids in health and disease. N Engl J Med ;0:0-.. Bruno NP, Beacham BE, Burnett JW. Adverse effects of isotretinoin therapy. Cutis ;:-.. Muhammad Tahir Ch. Efficacy and adverse effects of systemic isotretinoin therapy. J Pak Assoc Dermatol 0;:-.. Vitek L, Jirsa M, Brodanova M, et al. Gilbert syndrome and ischemic heart disease: a protective effect of elevated bilirubin levels. Atherosclerosis 00;0:-. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0. Schwertner HA. Bilirubin concentration, UGTA* polymorphism, and coronary artery disease. Clin Chem 00;:0-0.. Novotny L, Vitek L. Inverse relationship between serum bilirubin and atherosclerosis in men: a meta-analysis of published studies. Exp Biol Med (Maywood) 00;:-. 0. Tapan S, Karadurmus N, Dogru T, et al. Decreased small dense LDL levels in Gilbert's syndrome. Clin Biochme 0;():00-. BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 Table. Follow-up and comparative study of liver function tests in controls and patients with Gilbert s syndrome treated with isotretinoin. Case/Variable Gilbert s Syndrome Control P value Basal bilirubin. ± 0. 0.0 ± 0. <0.00 levels Bilirubin levels.0 ± 0. 0. ± 0. <0.00 after 0 Bilirubin levels. ± 0. 0. ± 0. <0.00 after 0 Basal AST levels. ±.. ±. 0. AST levels after 0. ±.. ±. 0. AST levels after 0. ±.. ±. 0. Basal ALT levels 0 ± 0.. ±.0 0. ALT levels after 0. ±.. ±. <0.0 ALT levels after 0. ±.. ±. 0. Basal GGT levels. ±. ±. 0. GGT levels after 0 ±.. ±. 0. GGT levels after 0. ±.. ±. 0. Mann-Whitney Test BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 Table. Follow-up and comparative study of lipid profile in controls and patients with Gilbert s syndrome treated with isotretinoin. Case/Variable Gilbert s Syndrome Control P value Basal cholesterol. ±.. ±. 0.0 levels Cholesterol levels. ±.. ± 0 0. after 0 Cholesterol levels. ±.. ± 0. 0. after 0 Basal triglycerides. ±.. ± 0. levels Triglycerides levels. ± 0.. ±. 0. after 0 Triglycerides levels. ± 0. ±. <0.0 after 0 Basal HDL levels. ±.. ±. 0. HDL levels after 0. ±.. ±. 0. HDL levels after 0. ±.. ±. 0. Basal LDL levels. ±.. ± 0. 0. LDL levels after 0. ±. ±. 0. LDL levels after 0. ±. 0. ±. <0.0 Mann-Whitney Test BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of BMJ Open 0 0 0 0 0 0 BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.

Page of 0 0 0 0 0 0 STROBE Statement checklist of items that should be included in reports of observational studies Item No Recommendation Title and abstract (a) Indicate the study s design with a commonly used term in the title or the abstract Introduction (b) Provide in the abstract an informative and balanced summary of what was done and what was found Background/rationale Explain the scientific background and rationale for the investigation being reported Objectives State specific objectives, including any prespecified hypotheses Methods Study design Present key elements of study design early in the paper Setting Describe the setting, locations, and relevant dates, including periods of recruitment, exposure, follow-up, and data collection Participants (a) Cohort study Give the eligibility criteria, and the sources and methods of selection of participants. Describe methods of follow-up Case-control study Give the eligibility criteria, and the sources and methods of case ascertainment and control selection. Give the rationale for the choice of cases and controls Cross-sectional study Give the eligibility criteria, and the sources and methods of selection of participants (b) Cohort study For matched studies, give matching criteria and number of exposed and unexposed Case-control study For matched studies, give matching criteria and the number of controls per case Variables Clearly define all outcomes, exposures, predictors, potential confounders, and effect Data sources/ measurement modifiers. Give diagnostic criteria, if applicable * For each variable of interest, give sources of data and details of methods of assessment (measurement). Describe comparability of assessment methods if there is more than one group Bias Describe any efforts to address potential sources of bias Study size 0 Explain how the study size was arrived at Quantitative variables Explain how quantitative variables were handled in the analyses. If applicable, describe which groupings were chosen and why Statistical methods (a) Describe all statistical methods, including those used to control for confounding Continued on next page (b) Describe any methods used to examine subgroups and interactions (c) Explain how missing data were addressed (d) Cohort study If applicable, explain how loss to follow-up was addressed Case-control study If applicable, explain how matching of cases and controls was addressed Cross-sectional study If applicable, describe analytical methods taking account of sampling strategy (e) Describe any sensitivity analyses BMJ Open: first published as 0./bmjopen-0-00 on 0 March 0. Downloaded from http://bmjopen.bmj.com/ on 0 August 0 by guest. Protected by copyright.