Accuracy of Laparoscopic Diagnosis of PID
Abstract & Commentary
Synopsis: Compared to histopathology, visual diagnosis of PID is neither accurate nor reproducible.
Source: Molander P, et al. Obstet Gynecol. 2003;101: 875-880.
Molander and colleagues evaluated the ability of 3 obstetrician/gynecologists (12 years average length of time in practice) and 3 third-year OB/GYN residents to accurately diagnose pelvic inflammatory disease (PID) by viewing laparoscopic images from each of 40 patients. The process was repeated 2 days later with the same images presented in a different order. Using histologically proven PID as the reference, overall diagnostic accuracy was 78%. Intra-observer reliability was only fair, although better for practitioners than for residents. Inter-observer reproducibility was poor to fair, again, better among practitioners. Using interpretation of photographic images to diagnose pelvic inflammatory disease appears to be unsatisfactory when compared to histologically proven diagnoses.
Comment by Frank W. Ling, MD
Chalk up another defeat for the "gold standard" concept. Visualization of PID via laparoscopy has generally been considered the definitive way to make the diagnosis. Unfortunately, "seeing" does not seem to be what it’s cracked up to be. Not only was the accuracy not as high as would be anticipated, but the ability for individuals to agree with themselves was only moderately good. Although the results are somewhat disappointing, they should not really surprise us. Haven’t we been told the same thing when standard colposcopic slides are shown to clinicians, ie, accuracy as well as both inter- and intra-rater reliability are suspect? Ditto for laparoscopic diagnosis of endometriosis, particularly the atypical presentations such as the vesicles white lesions and flare lesions. The same holds true for ultrasound images.
Admittedly, this study is artificial and somewhat removed from real-life clinical medicine. The physicians were viewing enlargements of pictures taken at the time of surgery. They did not have access to the physical examination findings, or laboratory results. They also could not manipulate the pelvic structures as they would if truly evaluating a real patient in real time. Without the context of the clinical presentation, one can argue that their ability to make an accurate diagnosis was compromised. It should be recognized, however, that such standard findings as edema, tubal erythema, adhesions, and cul-de-sac fluid should be reproducible.
The good news is that the practicing clinicians were more accurate and more reproducible than the residents. Thank goodness! At least the value of experience was supported. As we tell our residents now, "That’s why it’s a 4-year program." The take-home message of findings such as these addresses the very nature of PID. It remains a condition which, in many cases, is still commonly over- or underdiagnosed. We should still use all the appropriate tools we have to be as accurate as we can. We should certainly not expect laparoscopy to answer the question for us.