A 65-year-old woman with a history of mixed T2N0M0 (stage IIB) adenocarcinoma and T3N1M0 (stage IIIB) neuroendocrine carcinoma of the gallbladder presented to the oncology clinic for follow up. Nine years prior, her cancer had been discovered incidentally during a cholecystectomy performed for symptomatic cholelithiasis. She subsequently underwent a secondary radical procedure consisting of a regional lymphadenectomy, hepaticojejunostomy, Roux-en-Y, and resection of the liver, gallbladder bed, and bile duct, including stump of the cystic duct followed by adjuvant chemotherapy and radiation therapy. CT scans after completion of adjuvant therapy demonstrated no evidence of disease. Moreover, surgical pathology showed no evidence of malignancy in specimens taken from the radical procedure.

Upon current presentation for annual surveillance, CT scan demonstrated a finding of a 4.4 × 7.1 × 6.0 cm multi-cystic lesion in the right hepatic lobe (Figure 1). The patient denied any constitutional symptoms, including subjective fevers and abdominal pain. She remained afebrile, and routine labs, including hepatic function tests, were unremarkable except for moderate thrombocytosis. Notably, however, 1 week prior to this scan, the patient had presented to an outside hospital with complaints of fevers, chills, night sweats, and right-upper quadrant abdominal pain. Labs had shown a mild leukocytosis, but liver function tests were normal. She was empirically treated for suspected gastroenteritis with a five-day course of amoxicillin and discharged. Tumor marker labs obtained at the time of surveillance imaging resulted to show an isolated increased serum CA 19–9 level of 5,866 U/mL, elevated from 15 U/mL 1 year prior. Other serum tumor markers including carcinoembryonic antigen (CEA), chromogranin A, and Alpha Fetoprotein (AFP) were within normal limits. The patient was subsequently admitted for elevated CA 19–9 in the setting of a hepatic mass, with a differential diagnosis that included malignancy and hepatic abscess.

Ultrasound guided aspiration of the intrahepatic lesion yielded frankly purulent fluid, favoring diagnosis of hepatic abscess and requiring the placement of a percutaneous drainage catheter. One day after drainage, repeat CA 19–9 was found to have decreased to 2,398 U/mL. Aspirate cytology revealed predominantly inflammatory cells and culture of the material returned positive for Citrobacter braakii. The patient was started on intravenous piperacillin and tazobactam at first, but after return of susceptibilities, switched to 2-week course of oral levofloxacin and metronidazole. The intrahepatic abscess drain output remained between 10 and 50 mL per day for the remainder of hospitalization, while serum CA 19–9 levels trended down to 1,281 U/mL, 784 U/mL, and finally 435 U/mL at three, four, and 5 days after drain placement, respectively. On the fifth day, the patient was discharged home with the drain in place.

Repeat CT 8 days after discharge showed a hypoattenuating area decreased in size from previous scans. Sonographic and fluoroscopic examinations during the drain removal procedure confirmed resolution of the abscess. On clinical follow up 2 weeks later, the serum CA 19–9 level elevation had completely resolved, with the tumor marker measuring at a level of only 34 U/mL. The patient reported no recurrence of symptoms in the interim period. Another month later, magnetic resonance cholangiopancreatography confirmed near complete resolution of the abscess.

We performed a literature search of case reports in which CA 19–9 was elevated due to a hepatic abscess and found a total of eight reported cases (Table 1). The mean peak CA 19–9 in these cases was 1,538 (range 115–6,000). Three of these cases presented with fever and CT scans revealed hepatic lesions that were determined to be abscesses growing E coli. One was a 59-year-old man that was undergoing adjuvant treatment for pancreatic ductal adenocarcinoma. The second case was a 66-year-old woman with a history of hepatic hydatid cyst resection. The third case was that of an 87-year-old woman with no reported medical history (11–13). In all three cases, antibiotic treatment resulted in symptomatic improvement and a subsequent decline in CA 19–9 levels.

Organisms other than E. coli causing hepatic abscesses with an associated elevation in CA 19–9 have also been reported. An 85-year-old woman with a history of breast cancer had Klebsiella and MRSA cultured from a complex cystic mass in the liver as seen on ultrasound and magnetic resonance imaging (MRI) (14). A 71-year-old man with a history of a cholecystectomy had Gram-positive cocci in chains observed in drainage from a multiloculated liver abscess, though cultures were ultimately negative (15). Both individuals initially presented with fevers and elevated CA 19–9 levels and had symptomatic improvement after treatment with antibiotic therapy. A decline in CA 19–9 levels was reported for the 85-year-old woman, but no details were provided in the case of the 71-year-old man. In a separate case report, a 35-year-old male with cystic fibrosis and a history of lung, liver, and renal transplantation was hospitalized with a fever (16). After a negative infectious workup, an elevated CA 19–9 level was observed, and MRI findings showed multiple hepatic lesions resembling liver abscesses. Culture findings were not reported, but CA 19–9 declined, and symptoms resolved after antibiotic treatment.

Surgical excision of hepatic segments containing abscesses have also reportedly resulted in resolution of symptoms. A 31-year-old male presented with fevers, and ultrasound and CT scans revealed the presence of multiple hepatic lesions. Actinomyces spp. were found to be responsible for multiple liver abscesses and an associated increase in CA 19–9 (17). The diagnosis of Actinomyces was confirmed after surgical resection of hepatic segments IV-VII from which yellow pus was obtained and cultured. Symptoms improved rapidly after resection and antibiotics, and CA 19–9 levels normalized.

Only a single case of non-bacterial liver abscess causing elevated CA 19–9 has been reported. A 53-year-old male from Peru presented with fever, abdominal pain, nausea, and jaundice (18). A CT scan revealed a hepatic mass, and CA 19–9 was elevated. The patient developed septic shock and underwent exploratory laparotomy showing an abscessed hepatic mass. Hepatic biopsy performed during the procedure showed amoebic trophozoites. Following surgical and antibiotic treatment, the patient’s clinical status improved. CA 19–9 levels after treatment were not reported.