Chlamydia: A Disease Without a History
Michael Worboys Chlamydia: Most commonly reported STI in UK
Incidence of STIs, 1998-2008
140000
120000 New diagnoses 100000 Syphilis (primary and 80000 secondary) Gonorrhea 60000 (uncomplicated) New casesNew Chlamydia 40000 (uncomplicated) 20000
0 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 Year Venereal Diseases
1860-1930 Venereal Disease/s – syphilis and gonorrhoea
1940s Syphilis, gonorrhoea and ‘Other conditions’
“balanoposthitis, lymphogranuloma venereum (LGV), non-gonococcal urethritis (NGU), thrush, trichomoniasis, ulcus actum vulvae, vaginitis, vulvovaginitis, and warts.” (McLachlan, 1944) Venereal Diseases
Venereologists, 1940s
War – invalidism, tropics,
Special clinics
Bacteriologically- and Laboratory-oriented: Wassermann Reaction Salvarsan, Sulphonamides Antibiotics
Venereal Diseases
1948 WHO Expert Committee on Venereal Diseases First session, 12-16 January 1948
Venereal Diseases
1948 WHO Expert Committee on Venereal Diseases First session, 12-16 January 1948
Venereal Diseases
1948 WHO Expert Committee on Venereal Diseases
1950 A.H. Harkness, Non-gonococcal urethritis: including the genital manifestations of local and systemic diseases and infestations of the urinary tract with protozoa, metazoa and fungi.
1951 NGU first recorded, UK men only: 10,764 cases ( Cf. 14,975 gonorrhoea)
1965 NGU cases greater than gonorrhoea. Venereal Diseases
NGU or Non-Specific Urethritis (NSU)
1960s Puzzle Rising incidence – But treatable (sulphonamides and tetracycline) Unsatisfactory, residual category Was its cause? inflammatory, or an infection. ? Trachoma-like agent (TRIC) ? Mycoplasma ? Trichomoniasis ? Fungi ? Haemophilus ? Virus Venereal Diseases
NGU - NSU
1970s ‘In spite of much laboratory and other research, non- specific genital infection continues to be the venereologist’s most perplexing problem.’ Robbie Morton, 1975.
‘The Chlamydia genus is in fashion again’. Lancet, 1974
Cell culture of intracellular bacterium Chlamydia ≈ 25-58% of NGU/NSU Chlamydia in the Clinic
1980s NGU/NSU specific infections Chlamydia, mycoplasma, LGV Role in PID, Infertility Culture service
HIV-AIDS STI clinics, specialism Chlamydia co-factor in HIV/AIDS Labs + New biotech companies
GUM, Gynaecology, STIs Chlamydia in the Laboratory
C. trachomatis
Testing Direct ‘Observe’ the organism (culture/microscopy) Proxy Identify antibody Identify antigen
Sensitivity? – Specificity?
‘Gold Standard’ II now
‘Gold Standard’ then
http://www.chlamydiae.com/restricted/docs/labtests/diag_nucleicacidamplification.asp Chlamydia: A Disease without a History
NGU Chlamydia
NGU Chlamydia NGU > Chlamydia Chlamydia > NGU
New infection or newly recognised?
Increase? – ‘real’? – more you look, more you find?