Characteristics of undiagnosed liver abscesses on initial presentation at an emergency department.

Liver abscesses often present with nonspecific symptoms and laboratory examination abnormalities, resulting in missed diagnoses at emergency departments (ED). The purpose of this study was to determine if there are differences in presentation and prognosis between patients in whom liver abscess is diagnosed at an ED or once the patient has been transferred to a ward. Patients with a liver abscess who were discharged from our hospital between 2005 and 2007 were retrospectively reviewed. We compared the clinical characteristics between patients with liver abscess diagnosed at an ED or in a ward. Patients with liver abscess diagnosed at an ED had more abdominal pain (73.4%vs. 42.9%, p < 0.001), longer duration of symptoms before hospitalization (5.5 days vs. 3.8 days, p = 0.034) and fewer respiratory tract symptoms (12.5%vs. 24.5%, p = 0.05). Fewer cases with abnormal chest X-rays also existed for these patients (4.7%vs. 14.7%, p = 0.048). Cases not diagnosed at ED had delayed diagnoses for 4.41 +/- 3.16 days. Rates of mortality (6.3%vs. 8.2%, p = 0.740), shock (19.5%vs. 20.4%, p = 0.896), and length of hospital stay (19.6 days vs. 22.4 days, p = 0.173) were not significantly different between the patients diagnosed at an ED and those diagnosed later in a ward. Most information collected at the ED could not be used to aid diagnosis. Only abdominal pain was highly associated with liver abscess diagnosed at the ED. Undiagnosed liver abscess presented less abdominal pain and more symptoms or examination abnormalities related to infection of the respiratory and urinary tracts. Abdominal sonography should be performed more frequently at EDs to exclude liver abscess from differential diagnosis. However, further diagnosis and treatment while the patient with liver abscess is attending a ward does not affect prognosis.