Utility of HIDA Scan in Predicting Outcome of Cholecystectomy in Patients With Chronic Acalculous Gallbladder Disease? A Systematic Review

Abstract

Introduction: HIDA scan with gallbladder ejection fraction (GBEF) is used to evaluate chronic acalculous gallbladder disease (CAGBD), in which abdominal pain is attributable to biliary dyskinesia or chronic acalculous cholecystitis. In current practice, cholecystectomy is recommended when the GBEF is abnormal. We conducted a systematic review to evaluate the value of HIDA to predict patient response after cholecystectomy. Methods: In consultation with librarian, a literature search was done in PubMed for studies from January 1st 1990 - October 31st, 2016 to identify manuscripts with patients with abdominal pain without gallstones who underwent HIDA followed by cholecystectomy, and where follow-up data on pain resolution following surgery was reported. After pooling data, summary statistics were calculated for positive predictive value (PPV), negative predictive value (NPV), sensitivity and specificity of HIDA with abnormal GBEF in detecting patients whose symptoms resolve after cholecystectomy. Results: Initial literature search identified 74 articles. 15 studies met the inclusion criteria. Only 1 randomized controlled trial was identified (Yap et al.), which was small and low quality. 722 patients underwent cholecystectomy in the abnormal GBEF group, out of which 658 reported improvement (PPV = 91.1%). In the normal GBEF group, 132 patients underwent cholecystectomy and 107 patients reported improvement (NPV = 18.9%). Overall the sensitivity of HIDA EF was fairly high at 86.0% but the specificity was low (28.1%), corresponding to a false positive rate of 71.9%. The overall positive likelihood ratio (LR) is 1.20 and negative LR is 0.50. Conclusion: While the sensitivity and PPV of HIDA for detecting patients who have cholecystectomy responsive CAGBD is fairly high, the specificity is alarmingly low. This means that the majority of patients who don't improve following cholecystectomy have abnormal HIDA scans preoperatively. Also, a relatively high proportion of patients with normal HIDA scans report improvement in symptoms following surgery, which undermines the value of test. These findings indicate that HIDA scans may be less valuable in selecting patients for cholecystectomy, as a test with a high specificity would be better for this purpose. We suggest that physicians perform comprehensive evaluations to rule out other causes of abdominal pain before proceeding to HIDA, and to interpret findings of HIDA with caution, as well as educate patients regarding the limitations.Figure: Test characteristics of HIDA scan.Table. 2x2: table with summary data for all patients with preoperative HIDA scans undergoing cholecystectomy.Table: Studies included in review.