Erysipelothrix rhusiopathiae bacteraemia in a patient without endocarditis

Erysipelothrix rhusiopathiae bloodstream infection - A 22-year experience at Mayo Clinic, Minnesota

Erysipelothrix rhusiopathiae is a facultatively anaerobic Gram-positive bacillus found mostly in swine, fish and sheep. E. rhusiopathiae classically causes cutaneous eruptions in butchers, fish handlers and veterinarians. Based solely on case reports, 90% of E. rhusiopathiae bloodstream infections (BSI) have been associated with infective endocarditis (IE). To assess the true frequency of IE in E. rhusiopathiae BSI as well as other clinical associations, we performed a retrospective cohort analysis of E. rhusiopathiae BSI at Mayo Clinic. This is a single-centre, retrospective study conducted between 1/1/1994 and 20/6/2016 at Mayo Clinic in Rochester, MN. Medical records were reviewed for demographics, E. rhusiopathiae BSI, anti-microbial susceptibilities, incidence of IE, patient comorbidities, intensive care unit (ICU) admission and duration of antibiotics. Five cases of E. rhusiopathiae BSI were identified. Risk factors included animal exposures, immunosuppression, diabetes and kidney disease. All cases involved penicillin-sensitive strains and high-grade BSI. Four cases showed no signs of IE on transesophageal echocardiogram. All patients recovered fully with intravenous antibiotics. Our retrospective review illustrates that E. rhusiopathiae can cause invasive BSI in the absence of IE and that the previously reported 90% association between BSI and IE may be overestimated due to reporting bias. E. rhusiopathiae should be suspected in any patient with Gram-positive bacilli in blood cultures and the aforementioned risk factors. A limitation of our study was the low sample size, and future studies may involve multicentre collaborations and the use of polymerase chain reaction (PCR) or serologic testing to increase the number of diagnoses..

Erysipelothrix Rhusiopathiae Bacteremia without Endocarditis: Rapid Identification from Positive Blood Culture by MALDI-TOF Mass Spectrometry. A Case Report and Literature Review

Erysipelothrix rhusiopathiae is a Gram-positive bacillus that is infrequently responsible for infections in humans. Three forms have been classified: a localized cutaneous form (erysipeloid) caused by traumatic penetration of E. rhusiopathiae, a generalized cutaneous form and a septicemic form. The latter type of disease has been previously associated with a high incidence of endocarditis. Here we report a case of E. rhusiopathiae bacteremia in a 74-year-old man, probably started from an erysipeloid form, in which endocarditis did not develop. This case presents some particular and uncommon features: i) no correlation with animal source; ii) correlation between bacteremia and erysipeloid lesion; iii) absence of endocarditis. MALDI-TOF mass spectrometry allowed to obtain a rapid identification (within 4 hours from bottle positivity) of E. rhusiopathiae. Together with direct antimicrobial susceptibility testing, this approach could improve the rate of appropriate therapy for bloodstream infections due to this fastidious pathogen.

Occupational injury in a fishmonger with a macular rash, hepatosplenomegaly and pancytopenia

A 47-year-old fishmonger presented with a history of weight loss and lethargy. On investigation he was found to have myeloma. He presented again before follow up, with a 3-day history of fever and a maculopapular rash. He was admitted to the haematology ward and treated with broad-spectrum antibiotics. Blood cultures were found to be positive for Erysipelothrix rhusiopathiae. Penicillin treatment was given, and he made a good recovery. The importance of occupational illness in an already immunocompromised patient and of taking a proper social and occupational history from patients on admission is illustrated through this case.

Chronic monoarthritis of the knee in systemic lupus erythematosus

We describe a middle-aged lady with systemic lupus erythematosus who presented with chronic left knee monoarthritis without constitutional symptoms. The histology of synovial tissue taken at arthroscopy showed acute inflammation and Erysipelothrix rhusiopathiae, identified with some difficulty, was isolated from the enrichment broth only. Blood cultures were negative. Her history revealed significant exposure to pond fish. She responded well to intravenous penicillin and remains well 12 months later.