Spontaneous bacterial peritonitis from Salmonella: an unusual bacterium with unusual presentation

A 61-year-old female Arab patient was referred to our center for management of decompensated cryptogenic liver cirrhosis. She has type II diabetes mellitus since adolescence and hypertension of 5 years’ duration. She was also diagnosed with B-cell follicular non-Hodgkin lymphoma (NHL), stage IIIA, involving gastric mucosa and abdominal lymph nodes, 8 months ago. She was treated with rituximab (anti-CD20 monoclonal antibodies) and dexamethasone. However, she developed grade IV hepatic encephalopathy after three cycles of rituximab and chemotherapy was stopped.

Since the onset of encephalopathy, she started complaining of worsening ascites and lethargy, and had two more episodes of grade IV hepatic encephalopathy. By February 2008, she was referred to our center for evaluation for live donor liver transplantation (LDLT). She had no history of variceal bleeding or SBP and was not on prophylactic antibiotics. Initial physical examination showed moderate ascites and bilateral ankle edema, with normal chest and heart examinations. Blood tests showed normal creatinine and electrolytes, bilirubin 82 uM, albumin 26 g/l, alanine transaminase 22 U/l, aspartate transaminase 43 U/l, and alkaline phosphatase 73 U/l. Complete blood cell count showed slightly low hemoglobin at 11.3 g/dl, low platelets at 65,000/mm³, and normal white cells at 5,050/mm³. INR was elevated at 1.31. Computed tomographic (CT) scan revealed cirrhotic liver, splenomegaly, moderate ascites, and small, subcentimeter retroperitoneal lymphadenopathy. No gallstones were seen on CT or ultrasound scan. Positron emission tomography CT scan did not reveal any fluorodeoxyglucose-avid lesions to suggest active lymphoma, and ascitic fluid cytology was negative for lymphoma cells.

While she was undergoing evaluation for LDLT, she complained of acute onset of generalized abdominal pain. There was no fever, diarrhea, vomiting, or urinary symptoms. Clinically, she was afebrile and did not have tachycardia, but there was right-sided abdominal tenderness. A diagnosis of SBP was suspected and the patient was admitted for diagnostic paracentesis and empiric antibiotics therapy. Urinalysis and urine culture were unremarkable. Initial ascitic fluid analysis results showed a leukocyte count of 110/mm³, majority being lymphocytes, with lactate dehydrogenase, protein, and albumin at 54 U/l, 11 g/l, and 5 g/l, respectively. Her serum ascitic albumin gradient was 21 g/l, consistent with significant portal hypertension. However, 2 days later, ascitic fluid culture showed presence of group B Salmonella, which was sensitive to both ceftriaxone and ciprofloxacin. She was treated with an intravenous dose of ceftriaxone for a week followed by an oral dose of ciprofloxacin. Intravenous albumin infusion was also given concurrently to prevent renal impairment. Subsequent blood and stool cultures did not show growth of any organisms. She recovered well from the infection, with resolution of abdominal pain and tenderness; she underwent LDLT 2 weeks after diagnosis of Salmonella SBP. During laparotomy, no intra-abdominal lymphadenopathy was noted and explant liver did not show any evidence of active lymphoma. She has been recovering well from the transplant and remained well at her last follow-up 6 weeks posttransplant.