e Mycobacterium canariasense is a recently described late-pigmenting, rapidly growing mycobacterium linked to bacteremia in patients with underlying malignant diseases. We report a case of M. canariasense infection in a patient from Massachusetts with underlying diffuse B cell lymphoma, which was identified both by multilocus sequence typing and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). To our knowledge, this is the first description after its original identification in Spain and the first report of this opportunistic pathogen in the Americas.
CASE REPORT
We report a case of catheter-related bacteremia by Mycobacterium canariasense in a 42-year-old patient from Massachusetts with a history of intravenous drug abuse, hepatitis C, and diffuse B cell lymphoma.The patient presented complaining of fever (101.2°F), chills, vomiting, and nausea since 2 days prior to his admission. Six weeks earlier, he had been admitted and diagnosed with presumptive osteomyelitis of the sacroiliac joint for which he received empirical treatment with intravenous vancomycin for 6 weeks, completed a week prior to admission. Multiple sets of blood cultures were negative during this admission. At that time, a bone marrow biopsy was also performed for pancytopenia, and the patient was diagnosed with diffuse large B cell lymphoma with plasmacytoid features. He received two cycles of antineoplastic chemotherapy with cyclophosphamide, doxorubicin hydrochloride, vincristine, and prednisolone (R-CHOP), with the second cycle administered 2 days prior to admission and coinciding with the onset of fever.He did not report rashes, headache, cough, or gastrointestinal complaints, and his prior medical history was significant for bipolar and major depressive disorder as well as essential hypertension. Liver function tests were monitored for hepatitis C exacerbation but were within reference limits. A complete blood count was notable for total leukocytes of 5,150/mm 3 , with 50.5% neutrophils and 16.8% lymphocytes, decreased hemoglobin of 8.6 g/dl, hematocrit of 31.2%, and a normal platelet count of 381,000/mm 3 . Blood urea nitrogen, serum creatinine, and glucose were within reference ranges.Shortly after admission during a febrile episode, blood cultures were drawn and the peripherally inserted central catheter was removed and sent for culture using the roll-plate semiquantitative technique described by Maki et al. (1). The blood cultures in the aerobic bottles grew Candida dubliniensis, Candida albicans, Pseudomonas aeruginosa, and numerous Gram-variable rods. Candida species were determined with both the API 20C AUX and matrixassisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) systems. The catheter tip grew numerous Gram-variable rods as well as a group B beta-streptococcus.The Gram-variable rods (which grew from 4/4 bottles collected in two sets 3 days apart) grew on Lowenstein-Jensen (LJ) medium after 4 days (at 37°C) and revealed small, smooth, nonpigmented coloni...