sexually transmitted diseases Laboratory diagnosis of cexually transmitted diseases E. Van Dyck Institute of Tropical Medicine Antwerp, Belgium A.Z. Meheus University of Antwerp Antwerp, Belgium P. Piot Joint United Nations Programme on HIV/AIDS Geneva, Switzerland World Health Organization Geneva 1999 WHO Library Cataloguing in Publication Data Dyck, Eddy Van Laboratory diagnosis of sexually transmitted diseases / E. Van Dyck, A.Z. Meheus, P. Piot. 1. Sexually transmitted diseases - diagnosis 2. Diagnosis, Laboratory - methods I. Meheus, Andre 2. II. Piot, Peter Ill. Title ISBN 92 4 154501 1 (NLM Classification: WC 140) The World Health Organization welcomes requests for permission to reproduce or translate its publications, in part or in full. Applications and enquiries should be addressed to the Office of Publications, World Health Organization, Geneva, Switzerland, which will be glad to provide the latest information on any changes made to the text, plans for new editions, and reprints and translations already available. Q World Health Organization 1999 Publications of the World Health Organization enjoy copyright protection in accordance with the provisions of Protocol 2 of the Universal Copyright Convention. All rights re~e~ed. The designations employed and the presentation of the material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the World Health Organization concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or of certain manufacturers' products does not imply that they are endorsed or recommended by the World Health Organization in preference to others of a similar nature that are not men- tioned, or that may have been developed or become available since the preparation of this publication. Errors and omissions excepted, the names of proprietary products are distrngulshed by init~alcapital letters. The authors alone are responsible for the views expressed in this publication. Typeset and printed in Finland 95110436-Vammala-6500 - Contents Preface Acknowledgements 1. Gonorrhoea 1 .l lntroduction 1.2 Collection of specimens 1.3 Transport of specimens 1.4 Microscopy 1.5 Culture and presumptive identification 1.6 Confirmatory identification 1.7 Non-culture detection methods 1.8 Serology 1.9 Detection of plasmid-mediated antimicrobial resistance 1 .l0 Antimicrobial susceptibility testing 1 .l 1 Conservation of isolates 1 .l 2 References 1 .l 3 Selected further reading Chlamydia trachomatis infection 2.1 lntroduction 2.2 Collection and transport of specimens 2.3 Culture 2.4 Non-culture detection methods 2.5 Serology 2.6 lmmunotyping of isolates 2.7 Antimicrobial susceptibility testing 2.8 Conservation of isolates 2.9 References 2.10 Selected further reading 3. Syphilis 3.1 lntroduction 3.2 Microscopy 3.3 Serology 3.4 Serological test procedures 3.5 References 3.6 Selected further reading 4. Genital herpes 4.1 lntroduction 4.2 Collection and transport of specimens 4.3 Culture 4.4 Non-culture detection methods 4.5 Serology 4.6 References 4.7 Selected further reading 5. Chancroid 5.1 lntroduction 5.2 Collection and transport of specimens 5.3 Microscopy and non-culture detection methods 5.4 Isolation and identification 5.5 Serology 5.6 Antimicrobial susceptibility testing 5.7 Conservation of isolates 5.8 References 5.9 Selected further reading 6. Granuloma inguinale 6.1 lntroduction 6.2 Collection of specimens 6.3 Microscopy 6.4 Histopathology 6.5 Culture and immunological aspects 6.6 References 6.7 Selected further reading I. Vaginitis in adults A. Candidiasis 7.1 lntroduction 7.2 Collection of specimens 7.3 Direct microscopy 7.4 Culture B. Trichomoniasis 7.5 lntroduction 7.6 Collection of specimens 7.7 Direct microscopy 7.8 Culture 7.9 Non-culture diagnostic methods C. Bacterial vaginosis 7.1 0 lntroduction 7.1 1 Clinical diagnosis 7.12 Laboratory procedures 7.13 References 7.14 Selected further reading 8. Human papillomavirus infection 8.1 lntroduction 8.2 Collection of specimens 8.3 Laboratory procedures 8.4 The value of HPV detection 8.5 References 8.6 Selected further reading 9. Human immunodeficiency virus 9.1 Introduction 9.2 Serological screening procedures 9.3 Serological supplemental tests 9.4 HlV antigen detection 9.5 Proviral DNA assay 9.6 UNAIDS and WHO recommendations for thi selection and use of HIV antibody tests 9.7 References 9.8 Selected further reading Annex 1. Appropriate diagnostic tests for different levels of the laboratory system 99 Annex 2. Media, reagents and stains 102 Annex 3. Laboratoly supplies 113 Index reface Sexually transmitted diseases (STDs) are among the most common causes of ill- ness throughout the world and have been ranked among the top ten diseases in developing countries for which adults seek health care services. STDs are an important public health problem, not only because of their severe complications and sequelae but also because they increase the risk for transmission of the human immunodeficiency virus (HIV). Public health strategies for STD control include primary prevention (promotion of safer sexual behaviour and condom provision) and early adequate case man- agement of individuals with bacterial STDs. Accessible, acceptable and effective management of people with STDs implies the rationalization of decision-making by following simple flow-charts (algo- rithms) based on syndromic diagnosis, the inclusion of partner notification, and the promotion of condom use and safer sexual practices. Traditionally, the laboratory has played an important role in STD control pro- grammes. However, because of constraints in terms of cost, expertise and in- consistencies in supplies and other support, the practicality and availability of laboratory services are severely limited in many -if not most - settings. Laboratory tests should be confined to situations where they are essential for clinical or programmatic decisions. Priorities include: - monitoring of antimicrobial resistance of Neisseria gonorrhoeae (and of Hae- mophilus ducreyi if appropriate) to support treatment recommendations; - determining the etiology of common STD syndromes for the development of flow-charts for case management; - diagnosis of complicated or referred patients at reference centres; - case-finding of syphilis and HIV infection in pregnant women and in patients with other STDs; and - screening of blood donors for syphilis and HIV infection. Any surplus laboratory capacity is best directed towards diagnosis and case- finding of gonorrhoea and chlamydial infection in women, for which syn- dromic diagnosis is the least sensitive and specific. HIV infection and acquired immunodeficiency syndrome (AIDS) are of major concern to health care providers in all parts of the world. Laboratory services have an essential role to play in the diagnosis of infected persons, in screening blood for transfusion, in surveillance, and in research. This handbook presents a comprehensive guide of standard procedures for de- tecting and diagnosing STDs. It should be a useful tool for clinical microbiolo- gists and medical technologists. It is conceived as a practical bench manual, tuned to the needs and capacities of laboratories at different levels in the health care system. Each disease is covered in a separate chapter which provides detailed informa- tion on the collection and transport of suitable specimens and their subsequent testing in the laboratory. A summary of the appropriate diagnostic tests for use at different levels of the laboratory system, and lists of the media, reagents, stains and other equipment and materials required to carry out the tests are contained in the annexes.' l In some cases, the diagnostic tests, materials, reagents and media described in this book have been identified by the manufacturer's name or trademark. However, this does not imply that such tests and products are endorsed or recommended by WHO or the authors in preference to others of a similar nature that are not mentioned, or that may have been developed or become available since the preparation of this publication. Rather, the specific tests and products mentioned represent those that are known to the authors to be in common use. In the event that there are others in common use, WHO would be pleased to be so informed for the purpose of including a description of their use in future editions of this book. Photographs are reproduced by kind permission of the Division of Microbiol- ogy Institute of Tropical Medicine, Antwerp, Belgium, with special acknowl- edgements to: C. de Vroey, Division of Mycology, Institute of Tropical Medicine, Antwerp, Bel- gium G. Ieven, Clinical Microbiology, University Hospital, Antwerp, Belgium M. Lontie, General Practitioners' Medical Centre, Louvain, Belgium E. Stolz and J. van der Stek, Dermatology and Venereology, Dijkzigt, Rotterdam, Netherlands. onorrhoea 1:Introduction Gonorrhoea is an ancient disease which is transmitted almost exclusively hough sexual contact. The causative agent, Neisseria gonorrhoeae (gonococcus), infects only humans and is the etiological agent of lower urogenital tract infections, pelvic inflammatory disease and related sequelae (infertility and ectopic preg- nancy) in women, of urethritis and epididymitis in men, and of proctitis, pha- ryngitis, conjunctivitis and disseminated infection in both sexes. The clinical spec- hum of gonococcal infection is summarized in Table 1.1. Table