What Is Causing a Pyogenic Liver Abscess in This Immune-Competent Adult?

Authors:
Mazyar Malakouti, MD, and Sayed K. Ali, MD

Citation:
Malakouti M, Ali SK. What is causing a pyogenic liver abscess in this immune-competent adult? Consultant. 2014;54(9).

A 61-year-old Caucasian male with a past medical history of diabetes mellitus type 2, hyperlipidemia, obstructive sleep apnea, and poor dentition, presented to the emergency room with fevers, malaise, and right upper quadrant pain. His symptoms had been ongoing for about 1 week, except for the right upper quadrant pain that started 2 days ago. He denied any diarrhea, melena, recent travels, or exposure to sick individuals, but stated that he had some mild nausea and was unable to fully tolerate his meals.

Physical examination. The patient had a temperature of 39.5°C, with a blood pressure of 134/77 mm Hg, a heart rate of 122 beats/minute, and oxygen saturation of 97% on room air. He had poor oral hygiene, including gingivitis and multiple cavities, but no visible masses or lesions. No lymphadenopathy was appreciated. 

His heart sounds were normal with no audible murmurs or rubs. His lung fields were clear to auscultation. He had some mild tenderness to palpation in the right upper quadrant, without guarding or rebound. 

The remainder of his physical exam including his skin, palms and eyes were unremarkable. 

Laboratory tests. His white blood cell count was 13,200/mm³ (neutrophils 85%), platelets were 201,000/mm³, hemoglobin was 13.2 g/dL, aspartate aminotransferase and alanine transaminase levels were 22 U/L, total bilirubin was 0.8 mg/dL, and international normalized ratio was 1.1. HIV, hepatitis B, and C/CMV/EBV/influenza A+B tests all were negative.

His chest x-ray showed no infiltrates or effusions and a normal cardiac silhouette. He was started on empiric antibiotics in the emergency room. 

A transthoracic echocardiogram showed trace mitral and tricuspid regurgitation with no bacterial vegetation. This was later confirmed with a transesophageal echocardiogram. To further explore his right upper quadrant pain, an abdominal ultrasound was sought; revealing a hypoechoic fluid collection with internal debris seen on the right lobe of the liver, measuring approximately 6 cm by 5.4 cm by 5.8 cm (Figure 1). This was further verified via CT scan (Figure 2). 

Figure 1. Right, upper quadrant ultrasound showing abscess formation.

Figure 2. CT scan liver, showing abscess formation.

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