Evaluation of INNO-LiPA mycobacteria v2 assay for identification of rapidly growing mycobacteria

A total of 54 rapidly growing mycobacteria (RGM) isolated from patients attended in the two hospitals of Cádiz Bay (Spain) were selected during a seven-year-period (2000-2006) in order to evaluate the INNO-LiPA Mycobacteria v2 assay for mycobacterial identification, based on the reverse hybridization principle. The strains were cultured in Lõwenstein-Jensen and Middlebrook 7H9 media and identified to the species level by sequencing of the 16S rRNA, PCR-restriction enzyme analysis of the hsp65 gene, conventional tests and INNO-LiPA Mycobacteria v2 assay. By the molecular methods we identified a total of 12 different species: 23 Mycobacterium fortuitum, 11 M. chelonae, 10 M. abscessus, 2 M. senegalense, 1 M. alvei, 1 M. brumae, 1 M. mageritense, 1 M. mucogenicum, 1 M. neoaurum, 1 M. peregrinum, 1 M. septicum and 1 M. smegmatis. Fifty two strains (96.3 percent) were correctly identified by conventional techniques and 47 strains (87.0 percent) by INNO-LiPA Mycobacteria v2 assay. We find INNO-LiPA Mycobacteria v2 assay simple to perform but it provides few advantages in comparison with conventional methods and sometimes needs complementary tests to identify Mycobacterium fortuitum complex, M. chelonae complex and specific species due to the great heterogeneity in the RGM group.

Disseminated infection due to Mycobacterium chelonae with scleritis, spondylodiscitis and spinal epidural abscess

Mycobacteria other than tuberculosis (MOTT) have a low incidence as pathogens in human pathology. The most frequent clinical expression is the disseminated disease in subjects with compromised cellular immunity. Bacteriological characteristics in culture can generate confusion with other pathogens, which delays the appropriate diagnosis and treatment. We present a case of a disseminated infection due to Mycobacterium chelonae with scleritis, spondylodiscitis and spinal epidural abscess in a man with a medical background of cellular immunity deficit induced by therapeutic drugs. The antibiotic scheme of twenty-one weeks, during the follow-up period, controlled the infection, however, the optimum duration of treatment has not been established.

Isolation of Mycobacterium chelonae from wound infection following laparoscopy: A Case Report.

M. chelonae is a rare cause of human infection and is difficult to diagnose unless suspected for the same. A 55 year old healthy gynaecologist, diagnosed to have right inguinal hernia, underwent laparoscopic hernioplasty, after which he showed signs of post-operative wound infection which was confirmed to be due to M. chelonae. Definitive identification of this species of mycobacterium was possible by growth characteristics and biochemical tests. The organism was sensitive to Kanamycin, Clarithromycin, Ciprofloxacin and Amikacin. However, complete recovery from infection was possible after prolonged treatment with antibiotics to which the organism was sensitive.

Comparison of Mycobactericidal Activity of 12 Kinds of Disinfectants for Mycobacterium chelonae / 병원감염관리

BACKGROUND: Cleaning and disinfection of fiberoptic bronchoscope requires careful attention, especially to mycobacterium species because the contamination of mycobacteria could raise confusion on diagnosis. Recently, we detected contamination of Wydex(R) solution used in bronchoscope washer with Mycobacterium chelonae. In this study, we evaluated the mycobactericidal effect of 12 kinds of disinfectants for M. chelonae. METHOD: To evaluate the bactericidal effect of Wydex(R) 2%, Cidex(R) 2.25%, Cidex(R) 3%, Bacteriokiller (BK) disinfectant, Perasafe(R), HICLO-S(R), Lamicine(R), ethanol, Instrusept(R), Virkon(R), Betadine(R), and Vipon(R) against M. chelonae, culture was performed after exposure of two M. chelonae strains (ATCC 35749, the type strain and the strain isolated from contaminated Wydex(R) solution) to each disinfectant solution. The growth of organism was examined for up to 8 weeks. RESULTS: Growth of M. chelonae (reference strain of ATCC 35749 and isolated strain) was observed after a week incubation for Wydex(R) 2%, Cidex(R) (2.25%, 3%) and control. For BK disinfectant and Perasafe(R), they grew after 2-3 weeks, and 3-4 weeks, respectively. For HICLO-S(R) and Lamicine(R), only the contaminated strain grew after two and three weeks, respectively. For ethanol, Virkon(R), Betadine(R), Vipon(R), and Instrusept(R) , growth was not observed from either strain. CONCLUSIONS: On the basis of these results, Instrusept(R), virkon(R), ethanol, Betadine(R), and Vipon(R) were effective for the disinfection of M. chelonae. Especially, Instrusept(R) was thought to be useful as a disinfectant for bronchoscopes because it has advantages including non-corrosiveness, chemical stability, and non-irritativeness. And additional washing with ethanol might be effective. The finding that strain isolated from contaminated bronchoscopes was more resistant to disinfectants than reference strain suggested that the more resistant strains are selected throughout the improper disinfection.