An Unusual Case of Pyogenic Liver Abscess Caused by Community-acquired Methicillin-Resistant Staphylococcus aureus

Hepatic abscesses are the most common type of visceral abscesses. The annual incidence is estimated at 2.3 cases per 100,000 people and is more common in men than women. A considerable proportion of pyogenic liver abscesses are caused by hepatobiliary pathologies. However, it may also result from hematogenous seeding from the systemic circulation. Most pyogenic liver abscesses are polymicrobial in nature consisting of anaerobic and enteric gram-negative bacilli species. Less than 10% of cases are caused by Staphylococcus aureus. Of these, few are caused by Methicillin-resistant Staphylococcus aureus (MRSA) and even fewer from the community-acquired strain. The clinical manifestations of pyogenic liver abscesses usually include fever, abdominal pain and non-specific symptoms like nausea, vomiting, malaise, anorexia and weight loss. Treatment of pyogenic liver abscesses consists of source control with drainage and antibiotic therapy tailored to the isolated causative organism. We present a case of a 51-year-old Caucasian man who presented with severe right upper quadrant abdominal pain of 5 days in duration. Abdominal Computed Tomography (CT) showed a 7.7 by 6.0 centimeter multi-loculated mass in the right hepatic lobe with other scattered foci throughout the liver. The abscess was aspirated with a pigtail drain placed under CT guidance. The aspirated culture grew MRSA sensitive to Doxycycline and Trimethoprim/Sulfamethoxazole.