RT Journal Article SR Electronic T1 Diagnosis of pyogenic liver abscess by abdominal ultrasonography in the emergency department JF Emergency Medicine Journal JO Emerg Med J FD BMJ Publishing Group Ltd and the British Association for Accident & Emergency Medicine SP 273 OP 275 DO 10.1136/emj.2007.049254 VO 26 IS 4 A1 A C-M Lin A1 D Y Yeh A1 Y-H Hsu A1 C-C Wu A1 H Chang A1 T-N Jang A1 C-H Huang YR 2009 UL http://emj.bmj.com/content/26/4/273.abstract AB Background: Delayed diagnosis of pyogenic liver abscess remains a challenging problem in the emergency department because of the associated high morbidity and mortality.Objective: To evaluate the sensitivity of ultrasono-graphy in the diagnosis of pyogenic liver abscess in patients presenting to the emergency department and the factors that may influence this sensitivity.Methods: A retrospective study was conducted in patients diagnosed with pyogenic liver abscess in the emergency department (ED) of a tertiary care teaching hospital for a period of 5 years. Between May 2001 and April 2006, 268 patients diagnosed with pyogenic liver abscess were evaluated by ultrasonography and/or CT scanning. The age, sex, clinical presentation, location and number of abscesses and the underlying disease of these two groups were compared.Results: Of the 268 patients admitted via the ED who were discharged or died with a diagnosis of pyogenic liver abscess, there was a predominance of men (M/F 173/95) and the mean age was 57.6 years (range 17–90). 38 had false negative findings on ultrasonography (sensitivity 85.8%) and required abdominal CT scanning for definitive diagnosis. In the other 230 cases, ultrasonography alone was sufficient for diagnosis. Location of the abscess in segments 4 and 5 of the liver raised the sensitivity of ultrasound for diagnosis, while location in segment 8 was most associated with delayed diagnosis by ultrasonography. Right costal angle knocking pain was significant for pyogenic liver abscess even if ultrasound was negative.Conclusions: The size and location of the liver abscess and the underlying comorbid diseases may affect the diagnostic sensitivity of ultrasound for pyogenic liver abscess in clinical practice. A high index of suspicion should be maintained in patients with diabetes mellitus, previous biliary tract intervention or gastrointestinal malignancy. Follow-up CT scanning is recommended if right flank knocking pain is present, even if ultrasonography is non-revealing. A diagnostic protocol for liver abscess may be feasible in the future.