Pelvic Inflammatory Disease (PID) Overview:
PID encompasses all infections of the female upper reproductive tract, including endometritis, myometritis, salpingitis, tubo-ovarian abscess, parametritis, oophoritis, peri-appendicitis, perihepatitis, and pelvic peritonitis1. Per CDC guidelines, diagnosis requires at least one of three minimum criteria: cervical motion tenderness (CMT), uterine tenderness, and adnexal tenderness. These findings along with suspicion for PID is enough to start empiric treatment. Supporting criteria includes fever, abnormal discharge, positive GC/Chlamydia testing, elevated inflammatory markers, or abundant leukocytes on wet prep of vaginal fluid2.
The patient looks okay, and the results of STI testing are not going to come back today – how can I make this diagnosis during this visit?
The 2015 CDC guidelines as above (largely unchanged as of 2021) includes pelvic tenderness as a minimum criterion for PID and encourages having a low threshold for treatment if it is suspected given long-term complications of untreated/undiagnosed infection. However, a 2019 study by Farrukh et. al suggests that the pelvic exam itself is not necessary for diagnosis of cervicitis or PID – that history and/or positive lab findings alone are enough for this. This study used urine GC/chlamydia/trichomonas testing as the gold standard for diagnosis and compared likelihood of diagnosing infection with either history alone or history plus pelvic exam, finding only a 37.8% sensitivity associated with pelvic tenderness3,4.
In direct response, a 2022 meta-analysis conducted by Itawa et al. was performed, concluding that pelvic tenderness on exam is fairly sensitive for PID but not very specific. It included 14 studies through 2022 that looked at the sensitivity/specificity of pelvic, cervical motion or adnexal tenderness in diagnosing PID or any of the specific upper reproductive tract infections included under that umbrella. Studies involving cervicitis were only included if they addressed concomitant PID, not cervicitis alone. The analysis concluded that pelvic tenderness was 80% sensitive but only 40% specific for PID. When further stratified, the sensitivities and specificities are 72% and 50% respectively for CMT, and 87% and 27% respectively for adnexal tenderness. Studies included utilized laparoscopy alone or in combination with other testing including histopathology consistent with endometritis, TVUS or MRI findings as the reference diagnostic tool (rather than positive urine STI testing as in the Farrukh et al study).
The Itawa et al study does note that cervicitis alone does not always present with symptoms or physical exam findings and for this reason, the results of Farrukh et al’s studies should perhaps not be heavily leaned upon when there is suspicion for PID. Also in response to Farrukh et al, Annals of Emergency Medicine published a letter to the editor by Keaton et al “Why a Pelvic Exam is Needed to Diagnose Cervicitis and Pelvic Inflammatory Disease”, which importantly notes that because treatment duration differs between uncomplicated STI and PID, the implication of not performing an exam would be increased morbidity in affected patients. Additionally, a positive STI test is not a minimum criterion needed for diagnosis of PID per the CDC guidelines5. This is important to note especially in patients that have had recent negative STI testing but persistent symptoms – if tenderness is present and suspicion is high, do not write off PID as a consideration.
So basically, do the exam! Diagnosing PID is not as clearly defined at this time, but overtreatment is preferrable given the alternative – increased risk for ectopic pregnancy, infertility, chronic pelvic pain, menstrual disturbance, dyspareunia, and increased risk for borderline ovarian tumors1.
STI testing is still obviously useful in making this diagnosis. It's really easy to send off GC/Chlamydia and Trichomonas urine testing on my patients! Is that enough?
A 2023 meta-analysis of studies from 1995-2022 found that vaginal swabs were superior to urine samples in detecting GC/chlamydia/trichomonas, in accordance with CDC recommendations6.
Are self-collected rather than provider-collected swabs useful/reliable in diagnosis of these STIs?
Per two 2012 studies discussed in a great summary of the ER pelvic exam on emDocs, patient-collected vulvovaginal swabs are also appropriate for gonorrhea and chlamydia testing. This may be a good option for the patient who has a good story for one of these infections but does not feel comfortable with a pelvic exam7.
As always, when in doubt, utilize your specialists! Chat with Gyne or arrange close follow-up in clinic, providing thorough counseling on antibiotic adherence and return precautions (provided your patient is well enough to complete outpatient treatment).
Take-Home Points:
Pelvic/cervical motion/adnexal tenderness are very sensitive for PID but less specific.
Do the pelvic exam if clinical suspicion for PID is there – don’t rely on STI testing alone (negative or positive).
Swabs are better than urine samples for STI testing. Consider offering the self-swab option to patient’s if appropriate.
A couple of additional pearls for fun:
PID with no response to treatment after 7-10 days should raise suspicion for Mycoplasma genitalium infection.
Chronic (>30 days) PID may be caused by Mycobacterium tuberculosis or Actinomyces (having an IUD is a risk factor for this).
Authored By Dr. Nanditha Ravichandran & Dr. Eric Leser
References:
Weiss B, Shepherd SM. Pelvic Inflammatory Disease. In: Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 9th ed. McGraw-Hill; 2020:654-656.
Sexually transmitted infections treatment guidelines, 2021. Morbidity and Mortality Weekly Report. July 23, 2021. https://www.cdc.gov/std/treatment-guidelines/STI-Guidelines-2021.pdf.
Iwata H, Sugiyama Y, Satoi Y, Sasamoto N, Aoki T, Matsushima M. Diagnostic accuracy of pelvic examination in pelvic inflammatory disease: A meta-analysis. J Gen Fam Med. 2022;23(6):384-392. Published 2022 Aug 3. doi:10.1002/jgf2.572
Farrukh S, Sivitz AB, Onogul B, Patel K, Tejani C. The Additive Value of Pelvic Examinations to History in Predicting Sexually Transmitted Infections for Young Female Patients With Suspected Cervicitis or Pelvic Inflammatory Disease. Ann Emerg Med. 2018 Dec;72(6):703-712.e1. doi: 10.1016/j.annemergmed.2018.05.004. Epub 2018 Jul 2. PMID: 30251627.
Why a Pelvic Exam is Needed to Diagnose Cervicitis and Pelvic Inflammatory Disease
Mealey, KathleenBraverman, Paula K.Koenigs, Laura M.P. et al.
Annals of Emergency Medicine, Volume 73, Issue 4, 424 – 425
Aaron KJ, Griner S, Footman A, Boutwell A, Van Der Pol B. Vaginal Swab vs Urine for Detection of Chlamydia trachomatis, Neisseria gonorrhoeae, and Trichomonas vaginalis: A Meta-Analysis. Ann Fam Med. 2023;21(2):172-179. doi:10.1370/afm.2942
Curet B. EM@3AM: Pelvic inflammatory disease/tubo-ovarian abscess. emDocs. September 7, 2019. https://www.emdocs.net/em3am-pelvic-inflammatory-disease-tubo-ovarian-abscess/.