Characteristics of pelvic inflammatory disease where no sexually transmitted infection is identified: a cross-sectional analysis of routinely collected sexual health clinic data.
OBJECTIVE
Pelvic inflammatory disease (PID) occurs when pathogens, often sexually transmitted, ascend to the upper genital tract, yet a causative pathogen is not detected in a substantial proportion of diagnosed PID. We assessed the characteristics associated with PID in women in whom chlamydia, gonorrhoea, Mycoplasma genitalium (MG) and bacterial vaginosis (BV) were not detected ('pathogen-negative-PID').


METHODS
Cross-sectional analysis of routinely collected clinical data from new female patients attending a sexual health clinic between 2006 and 2013. Women were eligible if they had been diagnosed with PID and tested for genital chlamydia, gonorrhoea, MG and BV. Logistic regression was conducted to identify characteristics associated with pathogen-negative-PID.


RESULTS
Among 330 women with clinically diagnosed PID, 204 (61.8%, 95% CI 56.3% to 67.1%) had pathogen-negative-PID. Compared with pathogen-positive-PID, pathogen-negative-PID cases were more likely to be aged ≥30 years (adjusted odds ratio (AOR) 1.7, 95% CI 1.0 to 3.0), had less evidence of vaginal inflammation (AOR 0.5, 95% CI 0.3 to 0.9) and reported less unprotected sex (AOR 0.6, 95% CI 0.4 to 1.0).


CONCLUSIONS
These findings highlight uncertainties around PID diagnosis and aetiology. Pathogen-negative-PID could represent (i) a false positive diagnosis where the woman does not have a sexually transmitted infection (STI) or PID, (ii) PID of another microbiological aetiology or associated with a past STI or (iii) PID where the cervical infection has cleared. However, until diagnostic biomarkers are available, PID treatment should be based on clinical features and sexual risk.
Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Parkville, Victoria, Australia.
Jane L
JL
Goller
Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Parkville, Victoria, Australia.
Alysha M
AM
De Livera
Central Clinical School, Monash University and Melbourne Sexual Health Centre, Carlton, Victoria, Australia.
Christopher K
CK
Fairley
Kirby Institute, University of New South Wales, Kensington, New South Wales, Australia.
Rebecca J
RJ
Guy
Central Clinical School, Monash University and Melbourne Sexual Health Centre, Carlton, Victoria, Australia.
Catriona S
CS
Bradshaw
Central Clinical School, Monash University and Melbourne Sexual Health Centre, Carlton, Victoria, Australia.
Marcus Y
MY
Chen
Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Parkville, Victoria, Australia.
Jane S
JS
Hocking
D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D000292:Pelvic Inflammatory Disease / Q000382:microbiology / Q000473:pathology*; D060728:Reproductive Health; D012307:Risk Factors
BACTERIAL VAGINOSIS; CHLAMYDIA INFECTION; MYCOPLASMA; NEISSERIA GONORRHOEA; PELVIC INFLAMMATORY DISEASE