Use of Oral Budesonide in the Management of Protein-Losing Enteropathy After the Fontan Operation

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1 ORIGINAL ARTICLES: SURGERY: The Annals of Thoracic Surgery CME Program is located online at To take the CME activity related to this article, you must have either an STS member or an individual non-member subscription to the journal. Use of Oral Budesonide in the Management of Protein-Losing Enteropathy After the Fontan Operation Deepika Thacker, MD, Akash Patel, MD, Kathryn Dodds, CRNP, David J. Goldberg, MD, Edisio Semeao, MD, and Jack Rychik, MD Divisions of Cardiology and Gastroenterology, Children s Hospital of Philadelphia, Philadelphia, Pennsylvania Background. Intestinal inflammation is a component of the pathophysiology of protein-losing enteropathy after the Fontan operation. Oral controlled-release budesonide is 90% metabolized at first pass through the liver, has high enteric anti-inflammatory activity and relatively low systemic effects, and may be an ideal agent for use in treating this disease. Methods. Budesonide was administered to 9 patients (4 male) with protein-losing enteropathy after the Fontan operation. The median interval between the Fontan operation and diagnosis of protein-losing enteropathy was 4 years (range, 0.1 to 13.3). Prior interventional therapy included pulmonary artery stent (1), fenestration (3), pacemaker placement (3) and Fontan revision (2). Prior medical therapy included oral prednisone (5), heparin (4), sildenafil (2), infliximab (1), and octreotide (1), all without persistent success. The starting daily dose of budesonide was 9 mg for patients 4 years old or older, and 6 mg for patients less than 4 years of age. Results. Mean serum albumin level 3 months before starting budesonide was 1.9 g/dl (range, 1 to 2.4 g/dl). Serum albumin level improved in all patients within 6 months of starting budesonide (mean 2.9 g/dl; range, 2.2 to 3.8 g/dl). Albumin levels of 3 g/dl or more were achieved in 8 of 9 patients within a median of 4.3 months (range, 2 to 25). Side effects included Cushingoid features and osteoporosis (3), infection requiring antibiotic treatment (5), and acne exacerbation (1). Weaning from high initial dose to a lower dose was possible with sustained effect; however, discontinuation of budesonide resulted in recurrence of hypoalbuminemia. Conclusions. Oral budesonide is an effective therapy for treating protein-losing enteropathy after the Fontan operation. To maintain response, low-dose therapy must be continued. (Ann Thorac Surg 2010;89:837 42) 2010 by The Society of Thoracic Surgeons Protein-losing enteropathy (PLE) is a condition in which there is abnormal loss of serum proteins into the gastrointestinal tract lumen. First reported after the Fontan operation in 1980 [1], suspected prevalence of the disease is 3% to 15% [2]. Abnormal enteric loss of protein results in hypoalbuminemia and decreased intravascular oncotic pressure, leading to fluid accumulation in the tissues, effusions, and ascites. Immunoglobulins and coagulation factors are also lost, resulting in disturbances in immune and clotting function. Protein-losing enteropathy after the Fontan operation can lead to death, with reports describing as high as 50% mortality at 5 years from disease onset [2, 3]. Protein-losing enteropathy is a growing cause of morbidity and increasing concern for Accepted for publication Sept 29, Address correspondence to Dr Rychik, Children s Hospital of Philadelphia, Single Ventricle Care and Research Program, 34th St and Civic Center Blvd, Philadelphia, PA 19104; rychik@ .chop.edu. our patients with single-ventricle palliation, as survivors of the Fontan operation continue to age. The pathophysiology of PLE after the Fontan operation remains poorly understood. Abnormal hemodynamics related to the Fontan circulation, specifically, low cardiac output and elevated systemic venous pressure, likely provide the substrate for the disease. However, not all patients with this physiology manifest the disorder, suggesting that other factors play a role. Elevated mesenteric vascular resistance with impaired gut perfusion has been described in all patients with a Fontan circulation when compared with the healthy population, but more so in patients who also have PLE [4]. Inflammation likely plays an important role as inflammatory markers are often elevated in patients with a Fontan circulation, with further elevation in those with PLE [5]. Systemic corticosteroids such as prednisone have been used with some success, further suggesting a role for inflammation in the pathophysiology [6 8]. The significant side effects of corticosteroid agents, however, are a limiting factor in their usage by The Society of Thoracic Surgeons /10/$36.00 Published by Elsevier Inc doi: /j.athoracsur

2 838 THACKER ET AL Ann Thorac Surg ORAL BUDESONIDE FOR PLE AFTER THE FONTAN 2010;89: Oral controlled-release (CR) budesonide (Entocort; Astrazeneca AB, Sodertalje, Sweden) is a unique steroid drug with targeted enteric anti-inflammatory activity, but relatively low systemic activity, as it is 90% metabolized at first pass through the liver. Oral CR-budesonide has been used extensively and proven effective and safe in the management of pediatric inflammatory bowel disease [9 12]. Appreciating the role of inflammation and realizing that many patients respond to systemic corticosteroids, we administered oral CR-budesonide to patients with PLE after the Fontan operation in the hope it might prove useful in their management without some of the problems associated with the use of other corticosteroids. In this report, we describe our experience with the use of oral CR-budesonide for PLE after the Fontan operation with focus on its efficacy and side effects profile. Material and Methods Patient Population Between January 2005 and May 2009, 9 patients who had the Fontan operation and active PLE were started on a regimen of oral CR-budesonide. Patient characteristics including cardiac findings on echocardiography and cardiac catheterization were recorded. Chart review was performed with recording of response to oral CRbudesonide, efficacy, and side effects. Diagnosis of PLE was based on the clinical findings of peripheral edema or ascites and confirmation of hypoalbuminemia on multiple samples with serum albumin level less than 3.0 g/dl. Patients were excluded if another cause for hypoproteinemia such as renal losses or severe hepatic dysfunction could be identified, or if they had chronic draining pleural effusions as a possible cause for excessive protein loss. Oral CR-Budesonide Dosing and Patient Follow-Up Oral CR-budesonide is commercially available as 3 mg capsules. Capsules were either consumed orally or opened and sprinkled onto applesauce for patients unable to swallow the capsule. The starting dose of oral CR-budesonide was based on age: 9 mg (3 capsules) once daily for patients 4 years old or older, and 6 mg (2 capsules) for patients younger than 4 years. All patients remained on diuretic treatment, with diuretic dosage adjustments made as needed based on degree of edema and ascites present. During the course of treatment, the dose of oral CR-budesonide was tapered down to 3 mg daily and then 3 mg every other day, as clinical findings and serum albumin levels improved and were demonstrated to be stable. An attempt was made to completely wean patients off CR-budesonide if they continued to remain stable on this low dose. Serum albumin level before starting treatment was documented, as were subsequent serum albumin levels during the course of treatment. Side effects were recorded during follow-up clinic visits. Efficacy was measured based on serum albumin levels and clinical symptoms. As PLE was well documented and of long-standing duration in most patients, serial alpha-1 antitrypsin stool clearance was not routinely collected from each subject in relation to treatment. This study was performed with permission and in compliance with Institutional Review Board protocol (CHOP IRB ). Results Patient Characteristics Median age at performance of the Fontan operation was 2.7 years (range, 1.2 to 10.8). By nature of their congenital heart disease, the functioning systemic single ventricle was a left ventricle in 4 patients and a right ventricle in the other 5. Median duration between the Fontan operation and initial diagnosis of PLE was 4 years (range, 0.1 to 13.3). Types of Fontan operation included lateral tunnel (n 6), atriopulmonary (n 2), and extracardiac (n 1). Four were fenestrated at initial operation. One patient (patient 2) had device closure of the fenestration 6 years Table 1. Patient Demographics Patient No. Sex Diagnosis Age at Fontan (years) Fontan Type Age Oral CR-Budesonide Started (years) 1 Male TA, TGA (S, L, L) 1.9 LT/NF Female HLHS, DORV 2.7 LT/F a Female CCAVC unbalanced to RV, PA, R isomerism 1.4 LT/NF 15 4 Male HLHS 1.2 LT/NF 15 5 Female DILV, TGA (S, L, L), PS 10.8 AP/NF Male DILV, TGA, (S, L, L), VSD, PS 6 AP/NF Female Dextrocardia, TA, VSD, PS 3 EC/F Female HLHS 1.6 LT/F Male HLHS 3.4 LT/F 7 a Fenestration closed by catheterization before onset of PLE. AP atriopulmonary; CCAVC complete common atrioventricular canal; CR controlled release; DILV double-inlet left ventricle; DORV double-outlet right ventricle; EC extracardiac; F fenestrated; HLHS hypoplastic left heart syndrome; LT lateral tunnel; NF nonfenestrated; PA pulmonary atresia; PLE protein-losing enteropathy; PS pulmonary stenosis; R right; RV right ventricle; TA tricuspid atresia; TGA transposition of great arteries; VSD ventricular septal defect.

3 Ann Thorac Surg THACKER ET AL 2010;89: ORAL BUDESONIDE FOR PLE AFTER THE FONTAN 839 Table 2. Cardiac Hemodynamics From Cardiac Catheterization/Echocardiography Patient No. Function AVVR Fenestration Mean PAP (mm Hg) VEDP (mm Hg) Cardiac Index (L min 1 m 2 ) 1 Normal Mild Absent Moderately decreased Mild Absent Mildly decreased Mild Absent 4 Normal Moderate Present Mildly decreased Mild Present Mildly decreased Absent Absent Normal Mild Absent Normal Moderate Present Normal Mild Present AVVR atrioventricular valve regurgitation; PAP pulmonary artery pressure; VEDP ventricular end-diastolic pressure. before the onset of PLE. Prior treatment for PLE included a number of interventional therapies including fenestration creation (2 surgical, 1 catheterization), catheterbased dilation and stenting of existing fenestration (n 1), placement of a stent in the left pulmonary artery (n 1), pacemaker placement (n 3), revision of neoaortic valve prosthesis (n 1), and Fontan revision with takedown of atriopulmonary connection, modified Maze procedure, and placement of an extracardiac conduit (n 2). Prior medical therapies for PLE included oral prednisone (n 5), subcutaneous heparin (n 4), sildenafil (n 2), infliximab (n 1), and octreotide (1). None of these therapies offered sustained success; some medical therapies were withdrawn owing to side effects or lack of response. All patients were on diuretic regimens including furosemide at the time of initiation of oral CR-budesonide. Table 1 shows patient demographics and cardiac lesions. Table 2 characterizes the cardiovascular status of the patients treated, with data derived from echocardiography and cardiac catheterization performed after the diagnosis of PLE, but before treatment with oral CRbudesonide (patient 3 did not have cardiac catheterization before treatment). The median time between cardiac catheterization and initiation of oral CR-budesonide was 10 months (range, 1 to 44). Ventricular function and atrioventricular valve regurgitation are reported as the worst grade determined qualitatively by either echocardiography or angiography. One patient (patient 2) had moderately decreased ventricular function whereas all others had either mildly decreased or normal function. Moderate atrioventricular valve regurgitation was present in 2 patients. A patent fenestration was present in 4 (44%). Two patients had mild left pulmonary artery stenosis at the time of cardiac catheterization. Patient 7 had balloon dilation of preexisting stent with resolution of 2 mm Hg gradient across, and patient 9 had balloon dilation of preexisting stent and placement of another stent with no change in gradient of 2 mm Hg. No other systemic or pulmonary venous pathway obstructions were present. Pulmonary artery pressures ranged from 10 to 24 mm Hg (median 12 mm Hg; mean mm Hg); 2 patients had pressures greater than 15 mm Hg. Ventricular end-diastolic pressures ranged from 5 to 22 mm Hg (median 6 mm Hg; mean mm Hg). Cardiac index was relatively low in most and ranged from 1.7 to 4.5L min 1 m 2 (median 2.3L min 1 m 2 ; mean L min 1 m 2 ). Efficacy Improvement in laboratory values of serum albumin and subjective clinical improvement in symptoms (self-report of reduction in edema and improved well-being) were noted in all 9 patients treated with oral CR-budesonide (Table 3). Mean serum albumin level in the 3 months before starting oral CR-budesonide therapy for the group was low at 1.9 g/dl (range, 1 to 2.4 g/dl). Improvement was noted in all 9 patients within the first 6 months of treatment, with an increase for the group to a mean level of 2.9 g/dl (range, 2.2 to 3.8 g/dl). Albumin levels greater than 3 g/dl were achieved in 8 of 9 patients (89%). Individual time to reaching a serum albumin level of greater than 3 g/dl or maximum level achieved are listed in Table 3. The median time to achieve levels greater than 3 g/dl was 4.3 months (range, 2 to 25). Median duration of follow-up to date is 1.2 years (range, 0.4 to 3.9). None of the 9 patients received any supplemental albumin infusions after 2 months of initiation of oral CR-budesonide. Weaning With clinical improvement and at the point of achieving serum albumin levels of greater than 3 g/dl, an attempt at weaning to a lower dose of oral CR-budesonide was initiated to minimize potential side effects. Patient 5 had a peak albumin level of 2.5 g/dl and continued evidence of mild ascites, hence, no wean was attempted. Weaning commenced and continued gradually over a few weeks time in all other patients; however, weaning stopped once serum albumin levels dropped below 2.5 g/dl. Weaning from high initial dose (9 mg or 6 mg daily) to a lower dose of 3 mg daily or every other day was possible with sustained effect (serum albumin greater than 2.5 g/dl and no significant edema) in 8 patients. An attempt was made to completely stop oral CR-budesonide in 2 patients 1 from a dose of 3 mg every other day (patient

4 840 THACKER ET AL Ann Thorac Surg ORAL BUDESONIDE FOR PLE AFTER THE FONTAN 2010;89: Table 3. Laboratory Evidence of Efficacy of Oral CR-Budesonide Patient No. Duration on Oral CR-Budesonide (months) Pretreatment Albumin Level a (g/dl) On-Treatment Albumin Level b (g/dl) Time to Achieve Albumin Level 3 g/dl (months) NA a Mean serum albumin level in the 3 months before initiation of oral CR-budesonide. of oral CR-budesonide. CR controlled release; NA not applicable. b Mean serum albumin level in the first 6 months after initiation 1) and 1 from a dose of 3 mg twice weekly (patient 6). Both had albumin levels above 3 g/dl while on this low dose that were sustained for an extended period of time but dropped precipitously to less than 2.0 g/dl at cessation of oral CR-budesonide. Both patients were placed back on an initial starting dose of 9 mg daily with good response and have subsequently weaned once again to a lower dose. One patient (patient 2) stopped oral CRbudesonide after an infection and was briefly lost to follow-up. There was exacerbation of PLE within 6 months, at which time CR-budesonide was restarted at a dose of 9 mg/day. To date, no patient has been successfully weaned completely off oral CR-budesonide without a decrease of serum albumin to an unsatisfactory level. Side Effects Five patients had evidence of infection while on therapy that required antibiotic treatment. Three cases were mild: 1 patient had bilateral axillary lymphadenopathy and 2 had skin cellulitis, which responded to oral antibiotics. Two patients had more severe systemic infections, 1 had a urinary tract infection progressing to urosepsis and the other had pneumonia. Both of these patients required hospitalization and intravenous antibiotics. During therapy, 3 patients were diagnosed as having severe osteoporosis, although no imaging before onset of therapy was performed; therefore it was unclear whether that was related directly to oral CR-budesonide or to PLE disease itself. Three patients had observable facial Cushingoid features while on therapy. One patient had exacerbation of acne. No hypertension or laboratory evidence of hyperglycemia was noted. Comment To date, our understanding of PLE after the Fontan operation remains limited; however, we have developed a conceptual framework that is proving effective for management. We postulate that PLE after the Fontan operation is based on a fundamental alteration in hemodynamics, inherent in the physiology of relatively low cardiac output and elevated systemic venous pressure, findings present to some degree in all subjects with a Fontan circulation. The combination of low cardiac output and elevated systemic venous pressure alters the gastrointestinal perfusion profile, placing the gut mucosa at risk. Relatively low cardiac output and elevated venous pressure further create a picture of chronic heart failure that promotes systemic inflammation and the release of a multitude of mediators such as tumor necrosis factor alpha (TNF ). These mediators have been demonstrated to be elevated in adults with congestive heart failure and in patients with the Fontan circulation [5, 13 15]. Altered flow in combination with inflammation leads to a break in the integrity of the intestinal mucosa, resulting in enteric loss of protein into the gut lumen. In vitro studies lend support to this hypothesis. Increased permeability to albumin flux across a monolayer of intestinal epithelial cells occurs after treatment with TNF [16, 17]. Albumin flux is further potentiated by increased venous pressure and by the addition of heparanase to the preparation. Degradation of intestinal cell membrane glycosaminoglycans such as heparan sulfate may be the common molecular pathway for development of PLE. Infants born with congenital absence of intestinal heparan sulfate manifest a severe form of congenital PLE [18]. Utilizing this conceptual framework, therapies that either improve overall cardiac output and blood flow delivery to the gut (ie, fenestration, sildenafil, pacing, heart transplant) or reduce inflammation (corticosteroids) may prove effective in management of PLE after the Fontan operation [6 8, 19 27]. Administration of supplemental heparin may act to replenish depleted membrane stores of intestinal glycosaminoglycans, or may act as an anti-inflammatory agent [28 32]. In our report, we demonstrate oral CR-budesonide to be an effective agent for the treatment of PLE after the Fontan operation. In our 9 patients, no further improvement in hemodynamics short of heart transplantation was considered possible, hence a trial of this relatively new treatment modality was proposed. Oral CRbudesonide is an anti-inflammatory agent used for chil-

5 Ann Thorac Surg THACKER ET AL 2010;89: ORAL BUDESONIDE FOR PLE AFTER THE FONTAN 841 dren with Crohn s disease; it has high potency and targeted delivery at the level of the small intestine. It was therefore considered an ideal drug candidate for trial in our population. It was first suggested to us by a parent (of patient 1) just before being listed for heart transplant for severe PLE at age 18. This young man was successfully treated without need for transplant, has gone on to graduate college, and is now maintained, going on 2 years, ona3mgdose every other day with albumin levels greater than 3 g/dl and ostensibly no side effects. In our patients, onset of effective response to oral CR-budesonide was appreciated as a rise in serum albumin level from nadir as early as within 4 to 8 weeks of treatment; however, achieving relatively normal levels of greater than 3 g/dl typically required a few months of therapy. Therefore, when using this therapy, supportive measures such as albumin infusions may be necessary as an interim bridge to clinical response. Intestinal epithelial cells turn over approximately every 90 days, which may explain the lag in time between onset of treatment and response, as new cells may need to be generated before intestinal integrity is restored. Once satisfactory levels of albumin greater than 3 g/dl were achieved, drug dose could be successfully weaned down to a substantially lower dose than initial induction dose of either 6 or 9 mg daily in most of our patients. A continuous low level of anti-inflammatory treatment appears to be necessary to maintain good albumin levels, as no one has yet fully weaned off with sustained effect. Where this threshold exists seems to vary from patient to patient. An attempt at weaning in a slow manner should be initiated for all subjects to find this threshold. Dose can then be titrated to desirable effect; however, the long-term effects of low-dose therapy are unclear. A number of deleterious side effects were identified with treatment; however, it is unclear whether they can be directly related to oral CR-budesonide or to the PLE itself. Patients with severe PLE are typically immunocompromised, with loss of immunoglobulins and lymphocytes in the stool. While the disease is active, patients are at risk for infection. In our 2 subjects with serious infection, the infectious events took place while serum albumin levels were still below 3 g/dl. None of the patients with albumin levels greater than 3 g/dl while on oral CR-budesonide have experienced any serious infections. Curiously, these 2 patients with serious infection, and an additional third patient, exhibited significant Cushingoid facial features, findings more typically seen in patients treated with high-dose systemic corticosteroids. As oral CR-budesonide is highly metabolized at first pass through the liver and should not lead to Cushingoid changes at the dosage used, it is conceivable that these 3 patients have abnormal liver functionality, therefore manifesting significant systemic steroid effects despite the absence of laboratory serum abnormality on liver enzyme assay. Hepatic dysfunction is being recognized with increasing frequency in patients after the Fontan operation despite the presence of normal serum liver enzyme assay [33, 34]. Hepatic dysfunction may be uncovered through the process of administering agents that should normally be metabolized by a wellfunctioning liver, as may be the case in our 3 subjects. Caution should, therefore, be exercised when noting Cushingoid features in patients after the Fontan operation treated with oral CR-budesonide, and consideration given to lowering of the dose. Limitations of the Study Our study has a limited number of patients. It is, however, the only study to date on the use of oral CRbudesonide in the management of this complex condition. It also has the limitation of being a retrospective study. Ideally, a prospective, randomized, placebocontrolled study should be conducted to analyze the role of this medication in the management of PLE after the Fontan operation. With the efficacy of oral CRbudesonide seen in our study, and knowing the complications associated with PLE, we believe it would be difficult to justify doing such a study. In conclusion, oral CR-budesonide plays an important role in our management of PLE after the Fontan operation. As part of our algorithm, initial attention should always be focused on ways to improve hemodynamics, in particular cardiac output. Fontan baffle and branch pulmonary artery obstruction should be relieved, significant valvular disease addressed, and atrioventricular conduction synchrony created when absent. 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