Outbreak of Burkholderia cepacia pseudobacteraemia caused by intrinsically contaminated commercial 0.5% chlorhexidine solution in neonatal intensive care units.

BACKGROUND: Burkholderia cepacia is intrinsically resistant to certain antiseptics. The authors noted a sudden increase in the frequency of isolation of B. cepacia from blood cultures in a neonatal intensive care unit (NICU) of a university-affiliated hospital. AIM: To identify the source and intervene in the ongoing infections. METHODS: The cases were defined as patients with positive blood cultures for B. cepacia in an NICU between November 2014 and January 2015. Medical records were reviewed and NICU healthcare workers were interviewed. Samples of suspected antiseptics, blood culture bottles, cotton balls, gauze and a needle used in the NICU were analysed microbiologically. FINDINGS: During the outbreak period, B. cepacia was identified in 25 blood cultures obtained from 21 patients. The clinical features of the patients were suggestive of pseudobacteraemia. Regarding environmental samples, B. cepacia was cultured from 0.5% chlorhexidine gluconate (CHG) solution products that had been used as a skin antiseptic during blood drawing in the NICU. The clinical B. cepacia isolate and two strains obtained from 0.5% CHG exhibited identical pulsed-field gel electrophoresis patterns. After the CHG products were withdrawn, the outbreak was resolved. CONCLUSIONS: The pseudobacteraemia cases were caused by contaminated 0.5% CHG produced by a single manufacturer. Stricter government regulation is needed to prevent contamination of disinfectants during manufacturing. In addition, microbial contamination of antiseptics and disinfectants should be suspected when a B. cepacia outbreak occurs in hospitalized patients.

Frequency of neutrophil-specific antigens among Koreans using the granulocyte indirect immunofluorescence test (GIFT).

NA1, NA2, NB1, NB2, NC1, and NE1 are a group of antigens specifically expressed on neutrophils. Antibodies against neutrophil-specific antigens are involved in alloimmune neonatal neutropenia (ANN), autoimmune neutropenia (AIN), and transfusion-related acute lung injury (TRALI). We investigated the frequencies of NA1, NA2, NB1, and Mart antigens in 105 healthy Korean blood donors (65 males, 40 females) by the granulocyte indirect immunofluorescence test (GIFT) employing flow cytometry. Antigen and gene frequencies were: NA1, 0.78 and 0.53, respectively; NA2, 0.75 and 0.50, respectively; and NB1, 0.86 and 0.62, respectively. The Mart antigen was positive in all 105 subjects included in this study. The proportions of NB1-positive neutrophils among NB1-positive individuals were variable with a mean value of 72.0 +/- 20.2% (range, 27-100%). Differences in the frequency of the NA1 antigen have been reported between Asian and Caucasian populations. Our data support this variation. In addition, it was found that the frequency of the NA1 antigen in Koreans is significantly lower than in Japanese and Chinese populations (p < 0.05).