Institut national de santé publique du Québec 1

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1 Appendix A An opinion on the detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. gonorrhoeae resistance to ciprofloxacin Institut national de santé publique du Québec 1

2 An Opinion DETECTION OF GONOCOCCAL INFECTION IN QUÉBEC BIOMEDICAL LABORATORIES IN RESPONSE TO THE EMERGENCE OF N. GONORRHOEAE RESISTANCE TO CIPROFLOXACIN DIRECTION DES RISQUES BIOLOGIQUES, ENVIRONNEMENTAUX ET OCCUPATIONNELS JULY 2006 Institut national de santé publique du Québec 2

3 WRITTEN BY Raymond Parent, Scientific Advisor Groupe scientifique sur les infections transmissibles sexuellement ou par le sang (GITSS) Direction des risques biologiques, environnementaux et occupationnels Institut national de santé publique du Québec Dr. Marc Dionne, Director Direction des risques biologiques, environnementaux et occupationnels Institut national de santé publique du Québec With support from Isabelle Rouleau Direction des risques biologiques, environnementaux et occupationnels Institut national de santé publique du Québec IN COLLABORATION WITH Dr. Michel Alary, INSPQ Dr. Michel Couillard, INSPQ-LSPQ Dr. Laurent Delorme, Hôpital Charles Lemoyne Dr. Harold Dion, Clinique médicale l Actuel Dr. France Janelle, DRSP de la Montérégie Ms. Louise Jetté, INSPQ-LSPQ Dr. Annie-Claude Labbé, Hôpital Maisonneuve-Rosemont Dr. Michael Libman, Montréal General Hospital/MUHC Dr. Claude Laberge, MSSS Dr. Gilles Lambert, DRSP de Montréal and INSPQ Ms. Manon Lorange, INSPQ-LSPQ Dr. Pierre-Jean Maziade, Hôpital Pierre Legardeur Dr. Marc Steben, INSPQ Dr. Pierre Turgeon, Hôtel-Dieu de Sorel, Hôpital St-Luc/CHUM Dr. Jean Vincelette, Hôpital Saint-Luc/CHUM Institut national de santé publique du Québec 3

4 An electronic format (PDF) of the French document can be downloaded from the Institut national de santé publique du Québec Web site at: Reproductions for research or private study are authorized, in accordance with section 29 of the Copyright Act. Permission for any other use must be obtained from the Government of Québec, which holds exclusive intellectual property rights over this document. Authorization may be obtained by submitting a request to the central clearinghouse of the Service de la gestion des droits d auteur des Publications du Québec. The appropriate form can be downloaded from the following Web site: or by sending an to: droit.auteur@cspq.gouv.qc.ca. Data in this document can be cited, provided the source is acknowledged. GRAPHIC DESIGN Marie Pier Roy LEGAL DEPOSIT 1 ST TRIMESTER 2007 BIBLIOTHÈQUE ET ARCHIVES NATIONALES DU QUÉBEC LIBRARY AND ARCHIVES CANADA ISBN 13: (PRINT VERSION) ISBN 13: (PDF) Gouvernement du Québec (2007) Institut national de santé publique du Québec 4

5 TABLE OF CONTENTS 1 Background and mandate 1 2 Epidemiology of gonococcal infection in Québec Consequences of gonococcal infection Emergence of resistant strains of Neisseria gonorrhoeae Detection of N. gonorrhoeae using nucleic acid amplification testing (NAAT) Detection of N. gonorrhoeae in Québec biomedical laboratories 7 3 Recommendations Use of tests Medical practices Surveillance Knowledge development 12 Bibliography Annex 1 Experts in attendance at the 26 September retreat 17 Annex 2 Detection of gonococcal infection and antibiotic resistance results of a survey of Québec biomedical laboratories 21 Institut national de santé publique du Québec 5

6 1 Background and mandate The diagnosis of many infectious diseases depends on the detection of microorganisms in biological specimens. Nucleic acid amplification techniques (NAAT) do not require pathogen culture in medical microbiology laboratories. For now, culture testing is the only way to evaluate the antibiotic resistance of Neisseria gonorrhoeae (N. gonorrhoeae), the pathogen that causes gonococcal infection. In Québec, the number of reported cases of gonococcal infection is increasing, and ciprofloxacin resistance is endemic. Abandoning antimicrobial susceptibility testing could make it impossible to detect the emergence of new types of resistance and cause treatment failure. Culture and NAAT each have advantages and disadvantages regarding detection of N. gonorrhoeae. The choice of method used in Québec laboratories involves public health protection issues. The ministère de la Santé et des Services sociaux (MSSS) du Québec asked the Institut national de santé publique du Québec (INSPQ) to issue a scientific opinion on the best way of ensuring that detection of N. gonorrhoeae is optimal in Québec. The INSPQ opinion is based on the following: A description of the current situation, drawn up using a survey sent to Québec biomedical laboratories Consultations with primary-care clinical experts, medical microbiologists, public health professionals and laboratory experts An initial consultation by conference call identified the themes and issues that could be discussed during a subsequent meeting. Relevant publications and the results of a survey of Québec biomedical laboratories were available to the 14 experts who participated in this meeting (Annex 1). Preliminary versions of the opinion document were submitted on three occasions to the experts who attended the meeting as well as to other individuals who were absent but able to respond and interested in commenting. Further to the many comments received, additional consultations with a selection of experts were held. The following recommendations stem from these exchanges and from established consensus. Institut national de santé publique du Québec 6

7 2 Epidemiology of gonococcal infection in Québec The Table below shows that the incidence of reported cases of gonococcal infection among women remained relatively stable from 1996 to 2005, rising slightly from 3.9 per in 1996 (145 cases) to 4.3 per in 2005 (164 cases). Among men, however, the rate doubled, climbing from 9.1 per in 1996 (324 cases) to 19.5 per in 2005 (729 cases). Incidence rate of reported cases of gonorrhoea, by sex Province of Québec, Incidence per 1 00, Total Men Women : Adapted from: Surveillance des maladies à déclaration obligatoire (MADO) au Québec, Rapport annuel 2004, MSSS; 2005 data taken from the MADO database on 5 January, Discontinuing or not adopting safer sexual behaviours, linked to the trivialization of AIDS, is one of the factors that can explain this sustained increase in gonococcal infection. We also know that gonococcal infection is a cofactor for HIV transmission Consequences of gonococcal infection The complications of untreated or inadequately treated gonococcal infection can be especially serious in women. Indeed, women can develop pelvic inflammatory disease with long-term sequelae such as pelvic pain, ectopic pregnancy and infertility. 2 Institut national de santé publique du Québec 7

8 2.2 Emergence of resistant strains of Neisseria gonorrhoeae The emergence of antibiotic resistance in N. gonorrhoeae in North America dates back over 20 years. The first epidemic outbreak of penicillin-resistant gonorrhoea in an urban area was reported in the United States in Tetracycline resistance then emerged, with the first Québec cases reported in Resistance has become so common that it is now taken for granted, and it is no longer very useful to test isolated strains for susceptibility to these two antibiotics since their use is no longer recommended. Fluoroquinolone resistance emerged in the mid-1990s. 5 In Québec, the first cases of decreased susceptibility to ciprofloxacin (minimum inhibitory concentration [MIC] = 0.12 to 0.5 mg/l) 6 were identified in 1994, and the first case of resistance (MIC 1 mg/l) 6 occurred in The proportion of fluoroquinolone-resistant strains remained under 3% up to It then rose to 6.9% in In 2005, of the 936 strains that the LSPQ received, 179 (19.1%) proved to be resistant to ciprofloxacin, and 8 others were intermediately resistant. 8 The figure below indicates that the proportion of these strains increased rapidly in Proportion of strains of Neisseria gonorrhoeae reported to be resistant or intermediately resistant to ciprofloxacin by laboratories participating in the LSPQ monitoring program (1 strain/patient), 2005* % Jan. (6/8 3) Feb. (7/80) Mar. (6/6 1) April (7/52) May (11/ 72) Jun (10 /66) July (14 /87) A ug. (25/ 86) Sep. (18 /89) Oct (26 /84) Nov (35/103) Dec (24 /73) *Adapted from: LSPQ, StatLabo, Statistiques d analyses du Laboratoire de santé publique du Québec; February 2006, 5: 1-12 (Table 2). The LSPQ has confirmed that 187 of the 189 reported strains were resistant to ciprofloxacin. Institut national de santé publique du Québec 8

9 The rapid emergence of resistance has led to ciprofloxacin being removed from the list of antibiotics recommended for the treatment of gonococcal infection in both Québec 9 and Canada (in regions where the proportion of resistant strains is above 3% to 5%). 10,11 In Québec, epidemiological investigations into gonococcal infections are undertaken and are designed to support preventive interventions. In the Montréal region, reported male cases are only investigated if the strains are ciprofloxacin-resistant. Since June 2005, data collected during epidemiological investigations have been compiled centrally at the MSSS and analyzed at the INSPQ. Outside the Montréal area, 175 cases of gonococcal infection were reported to the MADO registry between 1 June and 30 November, There were 141 epidemiological investigations conducted, which included 107 male and 34 female cases. Of cases with information available about partners sex (130/141), 39.2% were men who reported having sex with men, 34.6% men who had had only female partners, and 26.2% were women. These data also indicate that men are particularly affected by ciprofloxacin resistance, since 29.9% (32/107) had a resistant strain compared with 14.7% of women (5/34). Rates of spontaneous mutation combined with rapid circulation of strains, extremely short generation time of microorganisms and growing exposure of pathogens to an increasingly limited number of effective antibiotics can only foster the emergence of new types of resistance in years to come. Strains showing decreased susceptibility to cephalosporins emerged in the early 2000s in the United States. 12 To date, no cephalosporin resistance has been reported in Québec. 2.3 Detection of N. gonorrhoeae using nucleic acid amplification techniques (NAAT) There are several significant advantages to using NAAT to analyze clinical specimens for pathogens. These tests are usually highly sensitive, providing that laboratories systematically take into account amplification inhibitors, which can yield falsenegative results when undetected. By including an internal control for each sample, it is possible to process and then retest samples for which amplification was initially inhibited. NAAT also provide an alternative to invasive specimen collection, such as urethral swabs for men or cervical swabs for women. Contrary to the case with culture, pathogen viability does not affect the result, and this simplifies transport and storage of specimens. Different techniques have been perfected and marketed: polymerase chain reaction (PCR), transcription mediated amplification (TMA) and strand displacement amplification (SDA). Institut national de santé publique du Québec 9

10 In Québec, all laboratories using NAAT reported using PCR (Amplicor or Cobas/Amplicor ), manufactured by Roche Molecular Systems, Inc. The specificity of PCR results for N. gonorrhoeae is sometimes inadequate, which affects the validity of results obtained using the Amplicor kit, particularly in low-prevalence populations. 13,14 Results that are initially positive should be confirmed with an alternative test (16S ribosomal RNA) to avoid communicating false-positive results. We will see below that Québec laboratories have adopted this practice. According to a study published in 2000, the sensitivity of confirmation testing could be problematic and thus produce false-negative results. 15 A recent publication 16 presented a systematic review of study results that measured the effectiveness of NAAT for detection of Chlamydia trachomatis and N. gonorrhoeae. The following table summarizes the main findings regarding PCR testing for N. gonorrhoeae with confirmation by 16S ribosomal RNA on positive results using the Amplicor kit. Performance of PCR for detection of N. gonorrhoeae Women (4 studies) Men (4 studies) Endocervix Urine Urethra Urine Sensitivity (%) 95% CI* Specificity (%) 95% CI* *95% CI: 95% confidence interval In this table, we can see that PCR sensitivity is inadequate when urine specimens from women are tested, which some laboratories reported doing. In addition, specificity is suboptimal for testing anal, rectal and pharyngeal specimens. 17 According to the results of a survey on current N. gonorrhoeae testing practices in Québec (Annex 2), no laboratory uses PCR to test anal, rectal or pharyngeal specimens. Amplicor and Cobas/Amplicor kits made by Roche Molecular Systems, Inc. have not been approved for such use in Canada. It should also be noted that PCR sensitivity should be compared with the sensitivity of culture as it is practised, that is, taking into account the conditions under which specimens are collected, stored, transported and cultured. In some environments, conditions are unfavourable and decrease culture sensitivity. The use of vaginal swabs to detect N. gonorrhoeae in women seems particularly promising, and swabs could eventually replace urine specimens At this time, the only kit approved for use on vaginal specimens is Gen-Probe Inc. s Aptima Assay. Institut national de santé publique du Québec 10

11 Sensitivities and specificities reported for this kit range from 71.9% to 96.1% and 99.3% to 100% respectively. 18,20 It is technically possible to detect mutations associated with N. gonorrhoeae resistance to certain antibiotics (e.g. mutations in the gyra and parc genes are associated with ciprofloxacin resistance). However, these analyses are not routinely available in Québec laboratories and, according to the experts we consulted, may not be for another 5 to 10 years. 2.4 Detection of N. gonorrhoeae in Québec biomedical laboratories As noted earlier, a survey of Québec biomedical laboratories was conducted to describe the current situation of N. gonorrhoeae detection in the province (Annex 2). An initial survey was sent to all laboratories concerned. Once the responses had been compiled, the laboratories that reported using NAAT were then asked to answer a mail and a telephone survey. About one out of five laboratories reported using NAAT. However, since these were the laboratories that processed the most N. gonorrhoeae testing requests, it means that half of the specimens received were tested using PCR. The 21 laboratories that reported using NAAT also all use the same PCR test Cobas/Amplicor manufactured by Roche Molecular Systems, Inc. They also reported having positive results confirmed with 16S ribosomal RNA. One of the advantages of NAAT is that these techniques can test for C. trachomatis and N. gonorrhoeae infections simultaneously. Some laboratories using this system report that in many cases they screen for both pathogens at the same time when only C. trachomatis testing is requested, even though indications for testing are not the same for the two diseases. 21 Confirmed results of certain unrequested tests are then sent to the clinicians. Other laboratories use culture testing. The fragile nature of N. gonorrhoeae and the precision required for successful culture make the wide variety of swabs and transportation media, and the maximum delays and transport conditions required to process a specimen matters of concern. Most laboratories that perform culture also undertake antimicrobial susceptibility testing, including testing for ciprofloxacin, or have it done elsewhere (82/93, 88%). The survey does not reveal the number of cases for which culture and PCR testing are done simultaneously. As a result, the exact number of cases for which susceptibility testing is performed is unknown. However, the monthly questionnaire about LSPQ s resistance surveillance program indicates that around 25% of all cases reported in Québec are detected only by PCR. These data allow us to estimate that culture and antimicrobial susceptibility testing are performed for about 75% of reported cases. Institut national de santé publique du Québec 11

12 3 Recommendations 3.1 Use of tests Considering that gonococcal infection is increasing in Québec, especially among men; ciprofloxacin resistance has spread rapidly; the emergence of new drug resistance is inevitable and must be monitored to avoid treatment failure; NAAT are being implemented gradually in Québec and do not allow for antimicrobial susceptibility testing outside a research situation; choice of type of specimen is decided in numerous and varied diagnostic and screening contexts, and, as a result, there are constraints; NAAT performance is suboptimal in some contexts; the invasive nature of urethral or cervical specimen collection procedures are associated with discomfort and pain; a person at risk is defined in the Guide québécois de dépistage des ITSS 21 the INSPQ recommends using the following tests: a) In symptomatic men - Culture of a urethral specimen is the preferred method of detection. When it is not possible to collect or send a specimen for culture without compromising the viability of N. gonorrhoeae (e.g. geographic isolation) - NAAT testing of a urethral or urine specimen is the preferred method of detection. Confirmation by 16S ribosomal RNA on the same specimen is necessary when an Amplicor or Cobas/Amplicor test result is positive. When it is not possible to obtain a urethral specimen (e.g. outreach efforts targeting at-risk groups) - NAAT testing of a urine specimen is the preferred method of detection. Confirmation by 16S ribosomal RNA on the same specimen is necessary when an Amplicor or Cobas/Amplicor test result is positive. The INSPQ reiterates that Gram stains are useful in the differential diagnosis of urethritis in men with urethral discharge from whom it is possible to obtain a urethral sample. Institut national de santé publique du Québec 12

13 b) In symptomatic men at risk - NAAT testing of a urine specimen is the preferred method of detection. Confirmation by 16S ribosomal RNA on the same specimen is necessary when an Amplicor or Cobas/Amplicor test result is positive. c) In symptomatic or asymptomatic women at risk - Culture of a cervical specimen is the preferred method of detection. When it is not possible to collect or send a specimen for culture without compromising the viability of N. gonorrhoeae (e.g. geographic isolation) - NAAT testing of a cervical specimen is the preferred method of detection. Confirmation by 16S ribosomal RNA on the same specimen is necessary when an Amplicor or Cobas/Amplicor test result is positive. When it is not possible to obtain a cervical specimen (e.g. outreach efforts targeting at-risk groups) - NAAT testing of a vaginal a or urine specimen is the preferred method of detection. Confirmation by 16S ribosomal RNA on the same specimen is necessary when an Amplicor or Cobas/Amplicor test result is positive. d) Anal, rectal and pharyngeal specimens - The only screening method validated for detection is culture. The gene amplification test (PCR) currently used in Québec has not been validated for use with rectal/anal and pharyngeal specimens. a At the time of writing this opinion, few data had been published on the sensitivity and specificity of PCR testing of vaginal specimens. However, existing data indicate that this type of specimen yields more reliable results than urine specimen tests. At this time, the only kit approved in Canada for use on vaginal specimens is the Gen-Probe Inc. Aptima Assay. Consequently, it is important to verify whether the laboratory to which the vaginal specimen is sent provides PCR testing (Amplicor or Cobas Amplicor ) for N. gonorrhoeae on this type of specimen. Institut national de santé publique du Québec 13

14 3.2 Medical practices Considering the wide variety of swabs, transport media and conditions observed in biomedical laboratories in Québec the INSPQ recommends that continuing education and information activities be implemented to promote optimal practices for gonorrhoea culture, and that biomedical laboratory staff, physicians and nurses involved in screening for gonococcal infection follow these practices. Considering that the practice, when prevalence is low, of unrequested testing of N. gonorrhoeae on samples collected for C. trachomatis testing is frequent; such a practice could yield incorrect test results; the reasons given for seeking C. trachomatis testing do not always justify testing for N. gonorrhoeae, since the epidemiology of these two infections is different in Québec; the INSPQ recommends that heads of biomedical laboratories question the relevance and appropriateness of proceeding with unrequested N. gonorrhoeae testing of specimens received for C. trachomatis testing. 3.3 Surveillance Considering that the LSPQ s N. gonorrhoeae surveillance program shows that about 75% of gonorrhoea cases reported in Québec still undergo antimicrobial susceptibility testing the INSPQ recommends that surveillance of N. gonorrhoeae resistance to antibiotics be maintained and reassessed on the basis of the change in total percentage of strains tested for antimicrobial susceptibility, as determined by the LSPQ. Institut national de santé publique du Québec 14

15 3.4 Knowledge development Considering that at this time, technology for the detection of N. gonorrhoeae is evolving rapidly; several factors determine the choice of detection tests offered by biomedical laboratories and choice of tests prescribed by clinicians; the INSPQ recommends that by 2008, data be collected on the technological developments, factors and constraints (performance, cost, availability of material needed to collect specimens and appropriate transport conditions) that will determine the type of gonorrhoea test to perform in the years to come. Institut national de santé publique du Québec 15

16 Bibliography 1. Fleming DT, Wassersheit JN. From epidemiological synergy to public health policy and practice: the contribution of other sexually transmitted diseases to sexual transmission of HIV infection. Sex Transm Infect 1999;75: Roy K, Wang SA, Meltzer M. Optimizing treatment of antimicrobial-resistant Neisseria gonorrhoeae. Emerg Infect Dis 2005;11: CDC. Epidemiologic Notes and Reports. Penicillinase-producing Neisseria gonorrhoeae Los Angeles. MMWR 1983;32: Greco V, Ng L-K, Catana R, LI H, Dillon JR. Molecular epidemiology of Neisseria gonorrhoeae isolates with plasmid-mediated tetracycline resistance in Canada: temporal and geographical trends ( ). Microb Drug Resist 2003;9: Dan M, Poch F, Shpitz D, Sheinberg B. Increases in fluoroquinolone-resistant Neisseria gonorrhoeae Hawaii and California. MMWR 2002;51: Clinical Laboratory Standards Institute. Performance standards for antimicrobial susceptibility testing. Sixteenth informational supplement. January Ringuette L, Trudeau T, Turcotte P et al. Emergence of Neisseria gonorrhoeae strains with decreased susceptibility to ciprofloxacin Quebec, Can Comm Dis Rep 1996;22: Surveillance des souches de Neisseria gonorrhoeae résistantes aux antibiotiques dans la province de Québec; Rapport On line: 9. Groupe de travail sur l infection gonococcique, MSSS. Preliminary recommendation for the treatment of Neisseria gonorrhoeae infection. Presented in January 2005 to the TCNMI [final report to come]. 10. Mann J, Kropp R, Wong T, Venne S, Romanowski B. Gonorrhea treatment guidelines in Canada: 2004 update. CMAJ 2004;171: Canadian Association for Adolescent Health. Sexual knowledge, attitudes and behaviours of Canadian teenagers and mothers of teens. Pro Teen 2006;15. On line: Wang SA, Lee MV, O Connor CJ et al. Multidrug-resistant Neisseria gonorrhoeae with decreased susceptibility to cefixime Hawaii, Clin Infect Dis 2003;37: Diemert DJ, Libman M and Lebel P. Confirmation by 16S rrna PCR of the COBAS AMPLICOR CT/NG test for diagnosis of Neisseria gonorrhoeae in a low-prevalence population. J Clin Microbiol 2002;40: Luijit DS, Bos PA, van Zwet AA, van Voorst Vader PC, Schrim J. Comparison of COBAS AMPLICOR Neisseria gonorrhoeae PCR, including confirmation with N gonorrhoeae-specific 16S rrna PCR, with traditional culture. J Clin Microbiol 2005;43: Mukenge-Tshibaka L, Alary M, Bernier F et al. Diagnostic performance of the Roche AMPLICOR PCR in detecting Neisseria gonorrhoeae in genitourinary specimens from female sex workers in Cotonou, Benin. J Clin Microbiol 2000;38: Cook RL, Hutchison SL, Østergaard L, Braithwaite RS, Ness RB. Systematic review: non invasive testing for Chlamydia trachomatis and Neisseria gonorrhoeae. Ann Intern Med 2005;142: Palmer HM, Mallinson H, Wood RL, Herring AJ. Evaluation of the specificities of five DNA amplification methods for the detection of Neisseria gonorrhoeae. J Clin Microbiol 2003;41: Institut national de santé publique du Québec 16

17 18. Schachter J, Chernesky MA, Willis DE et al. Vaginal swabs are the specimens of choice when screening for Chlamydia trachomatis and Neisseria gonorrhoeae: results from a multicenter evaluation of the APTIMA assays for both infections. Sex Transm Dis 2005;32: Shafer MA, Moncada J, Boyer CB et al. Comparing first-void urine specimens, selfcollected vaginal swabs, and endocervical specimens to detect Chlamydia trachomatis and Neisseria gonorrhoeae by a nucleic acid amplification test. J Clin Microbiol 2003;41: Knox J, Tabrizi SN, Miller P et al. Evaluation of self-collected samples in contrast to practitioner-collected samples for detection of Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis by polymerase chain reaction among women living in remote areas. Sex Transm Dis 2002;29: MSSS. Guide québécois du dépistage Infections transmissibles sexuellement et par le sang On line: (menu "Documentation", section "Professionnels de la santé", tab "Guides"). Institut national de santé publique du Québec 17

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19 ANNEX 1 EXPERTS IN ATTENDANCE AT THE 26 SEPTEMBER RETREAT

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21 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin ANNEX 1 EXPERTS IN ATTENDANCE AT THE 26 SEPTEMBER RETREAT Organized by: Dr. Marc Dionne, INSPQ Mr. Raymond Parent, INSPQ Ms. Isabelle Rouleau, INSPQ Experts: Dr. Michel Alary, INSPQ Dr. Michel Couillard, INSPQ-LSPQ Dr. Harold Dion, Clinique médicale l Actuel Dr. France Janelle, DRSP de la Montérégie Ms. Louise Jetté, INSPQ-LSPQ Dr. Annie-Claude Labbé, Hôpital Maisonneuve-Rosemont Dr. Claude Laberge, MSSS Dr. Gilles Lambert, DRSP de Montréal and INSPQ Dr. Pierre-Jean Maziade, Hôpital Pierre Legardeur Dr. Marc Steben, INSPQ Dr. Pierre Turgeon, Hôpital de Sorel, Hôpital Saint-Luc/CHUM Institut national de santé publique du Québec 21

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23 ANNEX 2 DETECTION OF GONOCOCCAL INFECTION AND ANTIBIOTIC RESISTANCE RESULTS OF A SURVEY OF QUÉBEC BIOMEDICAL LABORATORIES

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25 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin ANNEX 2 DETECTION OF GONOCOCCAL INFECTION AND ANTIBIOTIC RESISTANCE RESULTS OF A SURVEY OF QUÉBEC BIOMEDICAL LABORATORIES WRITTEN BY Raymond Parent Direction des risques biologiques, environnementaux et occupationnels Groupe scientifique sur les infections transmissibles sexuellement ou par le sang Institut national de santé publique du Québec Louise Jetté Laboratoire de santé publique du Québec Institut national de santé publique du Québec In collaboration with: Dr. Marc Dionne Direction des risques biologiques, environnementaux et occupationnels Institut national de santé publique du Québec 25

26 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin 1. Introduction Following a request made by the MSSS to the Institut National de Santé Publique du Québec (INSPQ), the LSPQ sent a survey to Québec biomedical laboratories. The purpose of the survey was to determine laboratory practices in the area of detection of Neisseria gonorrhoeae (N. gonorrhoeae). The process undertaken was the result of a request for an opinion on N. gonorrhoeae detection and screening. The object of this request was to determine which biomedical analyses should be chosen for N. gonorrhoeae detection in a context in which the rate of ciprofloxacin resistance is increasing. The goal of the survey was to establish whether the growing popularity of NAAT for N. gonorrhoeae detection was causing culture testing of specimens to be abandoned, thus limiting surveillance of the emergence of new antibiotic resistance. The objectives were as follows: a) To document NAAT implementation for detection of gonococcal infection b) To document the proportion of cases for which susceptibility to ciprofloxacin has been determined c) To document the constraints that affect the choice of tests that laboratories employ (procedures for specimen collection, storage and transport) This report presents the results of a study of biomedical laboratories in Québec carried out to accomplish these objectives. 26 Institut national de santé publique du Québec

27 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin 2. Methodology The survey of N. gonorrhoeae detection practices in 114 biomedical laboratories in Québec was conducted by the LSPQ during the summer of Laboratories that reported using NAAT also answered a second survey mailed during the fall, as well as a telephone survey. 3. Results 3.1 Response rate Of the 114 laboratories initially surveyed, 107 (94%) agreed to collaborate with the LSPQ. Table 1. Response rate by region Region No. of questionnaires No. of questionnaires Response rate sent returned Bas-Saint-Laurent % Saguenay-Lac-Saint-Jean % Capitale Nationale % Mauricie et Centre du Québec % Estrie % Montréal % Outaouais % Abitibi-Témiscamingue % Côte-Nord % Nord-du-Québec % Gaspésie-Îles-de-la-Madeleine % Chaudière-Appalaches % Laval % Lanaudière % Laurentides % Montérégie % Nunavik % Terres-Cries-de-la-Baie-James % Total % Institut national de santé publique du Québec 27

28 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin 3.2 Participating laboratories analysis profiles Almost all laboratories that responded (105/107, 98.1%) receive requests for N. gonorrhoeae testing. The majority of laboratories reported performing at least part of the N. gonorrhoeae tests in their own facilities, only 10 of them (9.5%) sending samples they receive to another laboratory. Data from one laboratory were removed from the analyses because of the high number of missing answers. This laboratory is in a specialized medical centre that performs three to five analyses a year. Accordingly, the data presented below are from the 94 laboratories that reported receiving requests for testing and that perform at least part of the tests in their own facilities. 3.3 Regions served The region of Terres-Cries-de-la-Baie-James is the only one not served by a local laboratory that performs N. gonorrhoeae testing. All specimens received for N. gonorrhoeae detection are sent to Montréal. Table 2 shows that most laboratories receive requests only from their own regions; only 12 offer detection services to laboratories located outside their regions. Table 2. Proportion of samples from outside a laboratory s region Number of laboratories % No outside samples received % 1% to 25% of samples received 9 9.6% 25% to 50% of samples received 2 2.1% Over 50% of samples received 1 1.1% 28 Institut national de santé publique du Québec

29 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin 3.4 Techniques used NAAT implementation occurred progressively (Figure 1). Before 2000, two laboratories offered this testing method. Since then there has been a constant increase, with two or three laboratories implementing it each year. At the time of the survey, 21 laboratories were using NAAT for detection of N. gonorrhoeae. Figure 1 Pace of NAAT implementation 25.0% 20.0% 20.4% % of laboratories using gene amplification 15.0% 10.0% 5.0% 5.4% 7.5% 10.8% 15.1% 17.2% 2.2% 0.0% The majority of laboratories (99%) still offer culture testing for N. gonorrhoeae. Of these, 20 laboratories (21%) use it concomitantly with NAAT (Table 3). Table 3. Types of techniques used Number of laboratories % Culture only % Both detection methods % NAAT only 1 1.0% Institut national de santé publique du Québec 29

30 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin Of the 21 laboratories offering NAAT for N. gonorrhoeae detection, 19 reported that most or all tests are performed in a context of testing for Chlamydia trachomatis and N. gonorrhoeae simultaneously. Of the 94 laboratories that receive requests for analyses and perform at least part of the tests, only 8 (8.5%) intend to modify their N. gonorrhoeae detection techniques in the next five years. Seven of them have indicated that they will modify the technique to offer NAAT (4/8) offer NAAT and change testing modalities for positive cultures (2/8) modify their culturing techniques (1/8). We did not, however, evaluate the number of laboratories that may stop using NAAT. Two of them indicated having done so since the end of the study. 3.5 Number of tests performed by type of technique and by region Only 21 laboratories use NAAT to test for N. gonorrhoeae; however, these laboratories are also the ones performing nearly half of requests for tests in Québec (Table 4). Table 4. Number of tests performed by testing method used and by year No. of tests performed Total NAAT Culture Total % of tests using NAAT 47.0% 51.2% 49.3% We have defined four categories of laboratory based on the number of tests performed annually: Small = 1 to 400 requests Medium = 400+ to 1500 requests Large = to requests Very large = ( requests) 28 laboratories (30.1%) 27 laboratories (29.0%) 29 laboratories (31.2%) 9 laboratories (9.7%) Table 5 shows the number of tests performed per year as well as the number of positive tests for each category. In all, for the two years documented, very large" laboratories performed 78% of NAAT and 10% of culture tests, and large" laboratories performed 18% of PCR and 70% of 30 Institut national de santé publique du Québec

31 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin culture tests. We also note that the proportion of PCR tests remained relatively stable during the two years of observation. Table 5. Number of tests performed and rates of positivity by year, technique and type of laboratory Laboratory Total NAAT Number Number Number + % + + % + of tests of tests of tests + % + Small Medium Large Very large Culture Number Number Number + % + + % + of tests of tests of tests + % + Small Medium Large Very large Table 6 presents the number of tests performed using each of the two techniques as well as the number and percentage of positive tests, by year and region. Note that in this Table, no data are presented for the region of Terres-Cries-de-la-Baie- James since all requests for N. gonorrhoeae testing were handled in a Montréal laboratory. Note also that culture testing is still offered in the other 17 regions. Data for positive NAAT results sent by the region of Nunavik for are incomplete. Indeed, there was an annual average of about 30 gonococcal infection reports in this region between 2000 and 2004; however, only 2 positive test results were reported to us for Institut national de santé publique du Québec 31

32 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin Table 6. Number of tests performed and rates of positive NAAT and culture tests, by health region NAAT Culture TOTAL Number Number Number + % + + % + of tests of tests of tests + % + Bas-Saint-Laurent Saguenay-Lac-Saint-Jean Capitale Nationale Mauricie/Centre du Québec Estrie Montréal Outaouais Abitibi-Témiscamingue Côte-Nord Nord-du-Québec Gaspésie-Îles-de-la-Madeleine Chaudière-Appalaches Laval Lanaudière Laurentides Montérégie 1201 n/a n/a n/a n/a Nunavik Total (with Nunavik) Total (without Nunavik) Institut national de santé publique du Québec

33 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin Table 6. (continued) NAAT Culture TOTAL Number Number Number + % + + % + of tests of tests of tests + % + Bas-Saint-Laurent Saguenay-Lac-Saint-Jean Capitale Nationale Mauricie/Centre du Québec Estrie Montréal Outaouais Abitibi-Témiscamingue Côte-Nord Nord-du-Québec Gaspésie-Îles-de-la-Madeleine Chaudière-Appalaches Laval Lanaudière Laurentides Montérégie 1358 n/a n/a Nunavik Total (with Nunavik) Total (without Nunavik) Institut national de santé publique du Québec 33

34 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin 3.6 Procedure for NAAT Two laboratories did not specify which NAAT kit was used in their facilities. The other 19 all used PCR (Amplicor or Cobas/Amplicor ) manufactured by Roche Molecular Systems, Inc. With this system, the CT/NG kit detects C. trachomatis and N. gonorrhoeae simultaneously in cervical, urethral and urine clinical specimens. In all, 16 of the 19 laboratories (84.2%) performed N. gonorrhoeae culture confirmation tests on positive PCR and tests to detect PCR inhibitors in the samples tested. Two laboratories did not provide this information, and neither reported positive test results during the period under study. Figure 2 presents the proportion of laboratories that report performing PCR to detect N. gonorrhoeae on various types of samples. Figure 2 Proportion of laboratories that report performing PCR tests, by type of sample (n = 21) Women Men % (17) 81.0 (17) 52.4 (11) 19.0 (4) 95.2 (20) 76.2 (16) 9.5 Endocervix Urine Urethra Vagina Urine Urethra Other* *Others: eye, throat and pharyngeal secretions, from men or women. Eleven of the 19 laboratories (57.9%) had restricted access to urine testing first-void urine or having not voided for at least two hours. Other access conditions mentioned were of more of an administrative nature. Indeed, some laboratories reported receiving samples only from certain targeted clinics, registering reservations in the report about results obtained based on sample provided; others reported not accepting specimens when their number of employees was too low to allow them to test rapidly and properly. Five of 17 laboratories performed PCR testing for N. gonorrhoeae even if culture testing was requested. In addition, 5 out of 17 laboratories performed this test with the swab received for C. trachomatis testing even if it was not requested. All 17 laboratories send unrequested test results to the clinicians. 34 Institut national de santé publique du Québec

35 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin 3.7 Procedure for culture testing There are 93 laboratories offering detection of N. gonorrhoeae by culture (with or without PCR). Table 7 shows specimen shelf life (before inoculation onto agar plate). We can see that seven laboratories are susceptible to producing false-negative results, since the viability of N. gonorrhoeae can be compromised in specimens older than 24 hours. Table 7. Maximum transportation and storage delays of specimens collected for culture testing Maximum delay reported Number of laboratories % 0 to 6 hours % 6 to 12 hours 9 9.7% 12 to 24 hours % 24 to 48 hours 5 5.4% 48 to 72 hours 2 2.2% Not specified 7 7.5% The specimens from the 93 laboratories offering culture testing are sent to laboratories by means of the types of transportation presented in Figure 3. Figure 3 Distribution of methods of transportation used to send specimens for culture testing* (n = 93) % of laboratories Hospital tranportation Pati ent himself/herself Taxi Messenger Rapi d delivery service Clinicians Internal requests Others *The categories are not mutually exclusive Of the 93 laboratories offering culture testing, 13 (14%) reported providing no transport material to their clients, and 2 others reported providing the material only to some clients. Of the 78 others, 64 (82%) said they did not charge for this material, 10 (13%) reported charging for it, and 4 (5%) said they asked some of their clients to pay for the material. Institut national de santé publique du Québec 35

36 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin Figures 4 and 5 show the types of swabs and transport methods used for culture. In both cases, we can see that a broad range of products are used. Figure 4. Distribution of types of swabs used to collect specimens for culture testing* (n = 93) % of laboratories Cotton Alginate Rayon Dacron Other *The categories are not mutually exclusive. Figure 5. Distribution of types of transport methods used for swabs sent for culture testing % of laboratories Charcoal Stuart Jembec Amies Other 3.8 Determination of antibiotic susceptibility of N. gonorrhoeae strains isolated by culture Most laboratories that perform culture testing (91.4%) also test for penicillinase-producing strains of N. gonorrhoeae, and 82 (88.2%) test some strains for antibiotic resistance (e.g. ciprofloxacin, ceftriaxone, cefixime, tetracycline, and others). 36 Institut national de santé publique du Québec

37 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin Figure 6 indicates the laboratories where identified strains are tested for antibiotic susceptibility. Figure 6. Laboratories where antibiotic susceptibility of strains isolated by culture is determined (n = 57) ,6 % of laboratories ,3 28,1 10,5 7,0 5 1,8 1,8 0 In their lab Other lab In their lab and elseqhere At the LSPQ In their lab at at the LSPQ At the LSPQ and elsewhere Not specified The 11 laboratories that report never testing N. gonorrhoeae strains for antimicrobial susceptibility send the strains to the LSPQ, where they are tested. Therefore, most strains are tested for antimicrobial susceptibility. It should be noted that laboratories are asked to send to the LSPQ all strains that are resistant to cephalosporin or ciprofloxacin. According to monthly questionnaires sent to hospitals by the LSPQ, current surveillance mechanisms reveal that strains reported to be resistant to targeted antibiotics are indeed forwarded to the Québec provincial laboratory. Figure 7 demonstrates that of hospitals that perform their own antimicrobial susceptibility testing, 3.3% report not performing ciprofloxacin susceptibility testing. Institut national de santé publique du Québec 37

38 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin Figure 7. Proportion of laboratories (of those not sending their strains to the LSPQ) that report testing for resistance to various antibiotics (n = 30) 100% test for susceptibility do not test for susceptibility No answer 90% 80% % % of laboratories 60% 50% 40% 30% % 10% 0% Ciprofloxacin Cefixime Ceftria xon e Penicillin Sp ectinom ycin Tetra cycline Oth er 38 Institut national de santé publique du Québec

39 Detection of gonococcal infection in Québec biomedical laboratories in response to the emergence of N. Gonorrhoeae resistance to ciprofloxacin 4. Conclusion The goal of the study was to determine whether the growing popularity of NAAT to detect gonococcal infection was causing culture testing of specimens to be abandoned, thus limiting surveillance of antibiotic resistance at a time when the emergence of N. gonorrhoeae resistance to ciprofloxacin in Québec is being observed. In our opinion, the high response rate (for each of the three questionnaires) emphasizes the bond of confidence that has existed for years between the LSPQ and the laboratories that participated in the study. Clearly, the development of tools for gene detection of a number of pathogens has many benefits and provides new screening opportunities. The costs to implement NAAT, however, are high, and consequently laboratories that receive a large number of testing requests are the first to install the necessary equipment. Once this is done, it is easier to offer detection of both C. trachomatis and N. gonorrhoeae on the same specimen. And yet, many specimens are collected for PCR testing for C. trachomatis. Some experts told us that it can be more costly to change the usual routine in order to test for C. trachomatis only. As a result, many N. gonorrhoeae tests are performed needlessly and without having been requested. Knowing also that false-positive results are inevitable, it is our opinion that the value of this practice is questionable. This simultaneous testing, as well as the fact that the presence of symptoms encourages sample collection for culture in men, probably largely explains the fact that positive results detected by PCR are clearly inferior to those observed for culture testing. We also note that susceptibility to ciprofloxacin is determined for most strains identified by culture, whether locally, in another laboratory or at the LSPQ. Since January 2005, the LSPQ has increased surveillance of resistance to ciprofloxacin, which has impelled some other laboratories to include this antibiotic when performing antimicrobial susceptibility testing. About two-thirds of laboratories (68.8%) provide their users with the material needed for specimen collection and transport free of charge for the purpose of culture testing for N. gonorrhoeae. The most remote health regions (Terres-Cries-de-la-Baie-James and Nunavik) send the specimens they receive to larger centres. N. gonorrhoeae can lose viability during transport; therefore, it is preferable in such contexts to opt for NAAT, since their performance is not linked to strain viability. New data are needed to more accurately determine procedures for sample collection, storage and transport, by type of specimen chosen. At this point, we need to talk to clinicians to understand the limitations of access, whether real or perceived, to one technique or another. We are unable here to ascertain whether or not these constraints act as barriers to culture testing of specimens. Institut national de santé publique du Québec 39