Human Reproduction vol.10 no.4 pp.923-926, 1995 The bubble test: a new tool to improve the diagnosis of endometriosis*

The objective of this study was to determine the clinical sensitivity and specificity of a bubbling phenomenon, including peritoneal surfaces, as a diagnostic test for endometriosis during laparoscopy. A prospectively con-trolled study of women with infertility of at least 1 year duration, who underwent laparoscopy, was conducted at a medical school-affiliated private infertility centre and research foundation. The study included 48 prospectively enrolled female infertility patients who underwent laparos-copy. Of these, 32 were found to suffer from endometriosis (group A) and 16 control patients did not show any evidence of disease (group B). The study involved the irrigation of the posterior cul-de-sac with short bursts of either saline or lactated Ringer's solution, utilizing a standard laparoscopic aspiration/irrigation system, and the subsequent observa-tion for an excessive soap-like bubbling phenomenon (posit-ive bubble test) in association with endometriosis. All 32 endometriosis patients (group A) demonstrated a positive bubble test. In contrast, only two of the 16 control patients (group B) were positive (P = 0.00242, Fisher's exact test; odds ratio, 8.000). A positive bubble test during laparoscopy was thus 100 % sensitive and 88 % specific for the diagnosis of endometriosis by laparoscopy, resulting in positive and negative predictive values of 94 and 100 % respectively. Since the literature provides considerable evidence that the diagnosis of endometriosis during laparoscopy is frequently missed, a positive bubble test during laparoscopy therefore may be considered a reason to search further (possibly with biopsies) for endometriosis in the absence of obviously visible disease. If confirmed, a positive bubble test could then become an even more accurate single diagnostic test for endometriosis than laparoscopy.