1.EVALUATION OF AN OGAWA MYCOBACTERIUM CULTURE METHOD MODIFIED FOR HIGHER SENSITIVITY EMPLOYING CONCENTRATED SAMPLES
DAVID LUBASI ; CHARITY HABEENZU ; SATOSHI MITARAI
Tropical Medicine and Health 2004;32(1):1-4
Two egg-based culture media were evaluated for detection of mycobacteria with Löwenstein-Jensen (L-J) as a gold standard. The conventional culture method was modified to improve laboratory diagnosis of tuberculosis in resource scarce countries by employing an inexpensive but sensitive and specific culture method. Sputum samples were collected from pulmonary tuberculosis suspects who visited the chest clinic at the University Teaching Hospital in Zambia. These samples were processed using three different sample treating procedures (with or without sample concentration) and cultured on L-J and Ogawa media for mycobacteria isolation. A total of 276 sputum samples were collected from 138 pulmonary tuberculosis suspects. When the L-J result was used as a standard, the sensitivity of Ogawa and modified Ogawa was 81.7% and 90.3% respectively. Similarly, the specificities of those methods were 96.7% and 92.3% respectively. In total, 90 samples (32.6%) were smear positive and 108 (39.1%) were culture positive. The positivity of each culture method was as follows: 93 (33.7%) in L-J, 98 (35.5%) in modified Ogawa, and 82 (29.7%) in original Ogawa. The contamination rate was 1.1%, 5.1%, and 9.8% for L-J, Ogawa and modified Ogawa respectively. The Ogawa culturing method is economical, simple and quick. Its low sensitivity was overcome by employing the concentration method, the sensitivity significantly improving from 81.7% to 90.3%. Ogawa techniques are ideal in overburdened TB laboratories with poor resources in developing countries.
2.First Susceptibility Testing of Mycobacterium tuberculosis for Second-line Anti-tuberculosis Drugs in Ghana
Tomoko Kato ; Kennedy Kwasi Addo ; Naomi Nartey ; Alexander Kwadwo Nyarko ; Frank Adae Bonsu ; Satoshi Mitarai
Tropical Medicine and Health 2014;42(1):53-55
We performed drug susceptibility testing on first- and second-line drugs in Mycobacterium tuberculosis (M. tuberculosis) for the first time in Ghana to obtain preliminary data on drug-resistant tuberculosis. Of 21 isolates (4 new cases and 17 treated cases), 5 (23.8%) were multi-drug resistant tuberculosis (MDR-TB) and 19 (90.5%) were resistant to at least one drug, but no extensively drug-resistant TB (XDR-TB) was identified. Since the target patients were Category II, IV or smear positive at follow-up microscopy, it is understandable that there were many drug-resistant TB cases. Six isolates were resistant to one or two second-line drugs, but the second-line drugs were not approved in Ghana. It is considered that the bacilli were imported from abroad. Preventing the import of drug-resistant TB bacilli is probably one of best ways to control TB in Ghana.
3.MYCOBACTERIUM TUBERCULOSIS AND gyrA VARIATION IN ZAMBIA
SATOSHI MITARAI ; LYNDON M KAFWABULULA ; CHARITY HABEENZU ; HIROSHI TERUNUMA ; DAVID LUBASI ; FRANCIS C KASOLO ; HARUMI SHISHIDO ; YOSHIO NUMAZAKI
Tropical Medicine and Health 2005;33(2):91-94
M. tuberculosis strains were isolated from clinically and bacteriologically confirmed patients to evaluate the susceptibility of clinical M. tuberculosis isolates to fluoroquinolone and to obtain molecular epidemiological information in Zambia,. The pathogens were subjected to susceptibility testing with isoniazid, rifampicin, ethambutol and streptomycin. The minimum inhibitory concentrations to ciprofloxacin, sparfloxacin and levofloxacin were also evaluated. The gyrA, fluoroquinolone resistance-determining region (QRDR), was sequenced and analysed. As a result, three of the 16 strains examined were resistant to isoniazid, rifampicin and⁄or streptomycin. All of the strains were susceptible to ciprofloxacin, levofloxacin and sparfloxacin. However, a unique gyrA gene variation of M. tuberculosis was identified in the isolates. One strain had a mutation (T73A) in QRDR. Additionally, 81.25% (13⁄16) of the strains tested had Thr at codon 88. Several variations of gyrA gene have been reported in relation to drug resistance. The gyrA variation data will be useful as epidemiological information. It may be important to monitor fluoroquinolone susceptibility even in developing countries for use against resistant M. tuberculosis infection, even though no fluoroquinolone resistance was observed in this study.
4.A Systemic Lupus Erythematosus Patient with Cutaneous Mycobacterium haemophilum Infection under Belimumab Treatment: A Case Report
Jonghun KIM ; Toshio HASEGAWA ; Kurisu TADA ; Yuki UEHARA ; Yukiko FUKUI ; Ayako NAKAMURA ; Satomi TAKEI ; Satoshi MITARAI ; Akio AONO ; Shigaku IKEDA
Annals of Dermatology 2023;35(Suppl1):S63-S66
A 38-year-old female with systemic lupus erythematosus (SLE) initiated belimumab treatment. One month later, she presented with a reddish painful swelling on her right lower leg.She was treated with ceftriaxone and vancomycin. However, novel erythematous papules and indurated nodules appeared on both her lower legs. Skin biopsy revealed microabscess formation with mixed cell granuloma surrounded by inflammatory cell infiltration within the dermis with subcutaneous fat tissue. A large number of acid-fast bacilli were observed with Ziehl–Neelsen staining. DNA sequencing of both the hsp65 and the 16S rRNA sequences showed a 100% match with the corresponding region of Mycobacterium haemophilum. Mycobacterial culture revealed satellite growth enhancement on Middlebrook 7H11 agar plates around a paper strip containing hemin. She was treated with levofloxacin, rifabutin, and ethambutol. Within 13 months, her cutaneous lesions improved markedly without any side effects. The B cell-targeted biologic belimumab, a fully humanized IgG1γ monoclonal antibody that inactivates B lymphocyte stimulator, has been considered to be beneficial for active SLE. However, this therapy could increase the risk for the development of biologic therapy-associated mycobacterial infections, both tuberculosis and nontuberculous mycobacteria infections.