Dyella japonica Bacteremia in Hemodialysis Patient

To the Editor: Patients who receive long-term hemodialysis are at great risk for infection (1,2), especially bacteremia, which may lead to devastating outcomes (3). Environmental bacteria are commonly recovered from dialysis fl uid, but their contribution to infection is less evident (4). We report a bacteremic episode caused by an unusual soil bacterium, Dyella ja-ponica. The patient was a 69-year-old Thai woman who had had end-stage renal disease for 8 months and was receiving hemodialysis twice a week via subclavian double-lumen permanent catheter. Approximately 6 h after hemodialysis, she became febrile. Physical examination showed temperature 38 o C, respiratory rate 22/min, heart rate 80/min, and blood pressure 130/60 mmHg. The rest of her examination was unremarkable and included normal state of consciousness, clear eyeground (fundus), and absence of a heart murmur. Her catheter was intact without evidence of exit site or cath-eter infection. Two blood samples, 1 each from the central line and peripheral line, were injected into BACTEC Aero-bic/F bottles and incubated in the BACTEC 9240 system (Becton-Dick-inson Diagnostic Systems, Sparks, MD, USA). A catheter-related bac-teremia was suspected, and vanco-mycin (1 g in intravenous drip) was prescribed. Other laboratory fi ndings included a total leukocyte count 14.5 × 10 9 /L (84% neutrophils, 16% lym-phocytes), blood urea nitrogen 38 mg/ dL, and creatinine 7.9 mg/dL. Urinal-ysis results were within normal limits. Urine and stool cultures were negative for pathogenic bacteria. The catheter was not removed for culture. On day 4 of incubation, both blood cultures showed growth, which was then placed onto 5% (vol/vol) sheep blood agar for subculture and produced deep yellow colonies. This uniform, gram-negative, oxidase-positive bacterium was not identifi able with manual phe-notypic tests and the API 20NE strip (bioMérieux, Durham, NC, USA). It was identifi ed by the Vitek 2 system (bioMérieux) and reported to be My-roides sp. with an excellent confi dence level (98.7% probability). To further confi rm the identifi ca-tion, we used 16S rDNA analysis. The primer pair forward 5′-AGAGTTT GATCMTGGCTCAG-3′ and reverse 5′-ACGGYTACCTTGTTACGAC TT-3′ were used to amplify the 16S rDNA by PCR. DNA extraction and PCR amplifi cation were carried out as described (5). The sequence of 16S rDNA amplicon (1,450 bp) was determined after electrophoresis and performed with the 3100 Genetic Analyzer (Applied Biosystems, Foster City, CA, USA) according to the man-ufacturer's recommendations. The 16S rDNA sequence of this isolate (strain RB28), deposited in GenBank under accession no. DQ984127, …