Clinical Presentation: This is a 40-year old chronically institutionalized male with a history of hepatitis C virus, cirrhosis, paranoid schizophrenia, esophageal varcies, PPD treated with isoniazid, rapid plasma reagin nonreactive, and human immunodeficiency virus negative. He is currently living in a mental hospital but goes home on the weekend. In late January 1999, he was admitted to The Johns Hopkins Hospital with two weeks of cough productive of occasional blood-tinged sputum, subjective fevers, and increased abdominal girth. On physical examination he was febrile and showed stigmata of end-stage liver disease including ascites, splenomegaly and jaundice. His admission white blood count was 12.6K. Two separate paracenteses revealed a transudative fluid with no growth of organisms. During this five-day admission six sets of blood cultures, two urine cultures and a stool for culture and ova and parasites were all negative. Four sputum cultures grew Candida albicans. A chest x-ray performed after intravenous hydration revealed a right lower lobe infiltrate. He was started on broad-spectrum antibiotics and switched to oral azithromycin. He defervesced and was discharged without a clear etiology of the pneumonic process.
Approximately 3 weeks after discharge the patient presented to the emergency department with complaints of chills, fevers, sweats, and pain around his umbilical hernia and left inguinal hernia. On physical examination he was afebrile and had a moderately distended abdomen with a fluid wave and splenomegaly. Bowel sounds were present. Paracentesis fluid contained 3,354 white blood cells per cubic mm with a differential of 84% neutrophils and 16% monocytes. Unfortunately paracentesis fluid was not sent for culture. Three sets of blood cultures grew Enterococcus cecorum after one day of incubation. Cefotaxime and ampicillin were begun with appropriate resolution of his abdominal pain. Repeat paracentesis showed a normal white blood count. The patient was discharged on spontaneous bacterial peritonitis prophylaxis five days after admission.
Enterococcus cecorum
Background: Enterococcus cecorum has previously been isolated from chickens, pigs, calves, horses, ducks, cats, dogs, and canaries but is practically unheard of in humans.
Clinical Presentation: Not known. Only one case of Enterococcus cecorum has been reported as a clinical isolate. A review of the literature revealed one reported case isolated from the blood of a "severely septicemic" patient who was malnourished. In the present case the organism was isolated from the blood however the patient was being treated for spontaneous bacterial peritonitis and this is likely the site of dissemination into the blood.
Diagnosis: The diagnosis can be difficult to make. As with all Enterococcus, these organisms are gram positive and arranged in short chains (see image at the microbiology newsletter web-site http://pathology5.pathology.jhmi.edu//micro/index.htm). Unlike most clinically important Entercocus spp., Entercoccus cecorum lacks the group D antigen and cannot produce PYR (pyrrolidonyl arylamidase). In the current specimen, typical biochemical tests were unable to identify this organism. Cell wall fatty acid analysis was performed but was not specific for an organism therefore the 16S ribosomal RNA gene was sequenced and matched against known sequences. The result of the 16S ribosomal RNA sequence was 99% homology with Enteroccus cecorum.
Therapy: The current patient was treated with cefotaxime and ampicillin which resulted in rapid resolution of his symptoms. This isolate of Enterococcus cecorum was sensitive to penicillin, ampicillin and levofloxacin.
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