Factors predicting significant pathology on ultrasonography in women presenting with non-specific lower abdominal pain

Abstract

INTRODUCTION Ultrasonography is used frequently to exclude significant pathology in young women presenting with nonspecific lower abdominal pain (NSLAP). This study examined parameters that predicted the likelihood of significant findings on ultrasonography. These results could be used to select patients for priority imaging or identify those who could be managed with no ultrasonography. METHODS A total of 65 women with NSLAP were identified from 283 admissions. Group 1 (n=42) consisted of patients with normal imaging. Group 2 (n=23) included patients with ‘positive’ scans requiring treatment. White cell count (WCC), C-reactive protein (CRP) levels, platelet count, age, duration of pain and length of stay in hospital were compared between the groups. RESULTS The median WCC and CRP were greater in Group 2 than in Group 1: 15 x 10 9 /l and 123mg/l versus 11 x 1071 and 72mg/l respectively (p=0.01 and p=0.05). CRP was a weak predictor of positive pathology on ultrasonography (area under curve [AUC]=0.66, p=0.027) and WCC was a strong predictor of abnormal pathology on ultrasonography (AUC=0.7, p=0.005). A WCC of >12.8 x 10 9 /l was 65% sensitive and 71% specific in predicting subsequent pathology on ultrasonography. The median wait for ultrasonography was 24 hours (range: 1-96 hours). CONCLUSIONS This study failed to define any criteria that could select patients not requiring ultrasonography. Since ultrasonography is a relatively cheap and safe investigation, its continued use to screen women with NSLAP is justified. WCC should be used to prioritise imaging.