Case Presentation: A 72-year-old woman with breast cancer treated with lumpectomy and radiation in 2021, diverticulosis diagnosed by colonoscopy in 2018, and recent dental work, presented to the emergency department with cough, congestion, diarrhea, dizziness, and an episode of near-syncope. Two days prior to presentation she tested positive for COVID-19 and was prescribed nirmatrelvir / ritonavir. On arrival, vital signs were notable for a temperature of 37.9C, tachycardia (122 beats per minute), hypotension (88 / 53 mm Hg), and mild hypoxia (91% on room air). Physical examination revealed bibasilar crackles. Initial laboratory workup showed an elevated white blood cell count (22.1 x 109/L), hyponatremia (128 mEq/L), transaminitis (AST 109 U/L, ALT 55 U/L, alkaline phosphatase 254 U/L), and a positive COVID-19 PCR. A chest X-ray demonstrated a hazy opacity in the left lung base. The patient was admitted with a presumptive diagnosis of COVID-19 with superimposed bacterial pneumonia and was started on intravenous hydration, broad spectrum antibiotics, and dexamethasone. On day 3, blood cultures resulted positive for Streptococcus intermedius and antibiotics were narrowed to ceftriaxone. Dexamethasone was discontinued as the patient had been weaned off supplemental oxygen. By day 6, the patient continued to report fatigue despite stable vital signs and a downward trend in white blood cell count. The elevation in her liver enzymes, attributed to COVID-19 since admission, had decreased but persisted (AST 54 U/L, ALT 66 U/L, alkaline phosphatase 150 U/L). Further evaluation with a right upper quadrant ultrasound was pursued and revealed a necrotic mass in the right lobe of the liver. A subsequent CT of the abdomen showed a 5 x 8 x 5 cm multiloculated liver collection. Given the patient’s history of breast cancer and concern for metastatic disease, an MRI of the abdomen was obtained and confirmed a multiseptated hepatic abscess. The location of the abscess precluded safe percutaneous drainage. In consultation with Infection Disease, the patient was transitioned to amoxicillin / clavulanate, with a plan for repeat imaging in three weeks to reassess the abscess.
Discussion: Streptococcus intermedius is a gram positive bacterium that belongs to the Streptococcus anginosus group (SAG), a subgroup of the viridans group streptococci. While it normally colonizes the oropharynx, gastrointestinal tract, and genitourinary system, S. intermedius has the potential to act as an opportunistic pathogen. A distinctive feature of this organism is its propensity to cause abscess formation, which can occur in various body sites including the liver, brain, and lungs. We suspect that our patient developed bacteremia from her dental procedure which led to hematogenous seeding of the liver. Her remote history of diverticulosis may have been another potential risk factor. This case posed a diagnostic challenge as the patient did not have any fevers since admission or abdominal pain, which are typically associated with a pyogenic liver abscess. Her concurrent COVID-19 diagnosis further complicated the clinical picture as symptoms such as malaise and transaminitis are commonly associated with a viral syndrome.
Conclusions: A high degree of vigilance is necessary in patients with S. intermedius bacteremia as this organism is abscess forming. Symptoms of a pyogenic liver abscess could be nonspecific and the absence of fever or right upper quadrant pain should not delay further investigation.
