Details

Autor(en) / Beteiligte

• Yu, Shuying

Titel

Clinical and Molecular Characteristics of Tsukamurella Tyrosinosolvens Causing an Infection Misdiagnosed as Mycobacteria Tuberculosis, and its Antimicrobial Susceptibilities

Ist Teil von

• Indian journal of clinical biochemistry, 2022-05, Vol.34 (S1), p.S170

Ort / Verlag

Springer

Erscheinungsjahr

2022

Quelle

Elektronische Zeitschriftenbibliothek (Open access)

Beschreibungen/Notizen

• Tsukamurella species are aerobic gram-positive organisms from the order Actinomycetales which are generally a weakly acid-fast, nonsporeforming rod and shares many features with Mycobacterium. This study aims to investigate one T. tyrosinosolvens isolate from patients with lung disease who was misdiagnosed as tuberculosis. Species identification was performed by sequencing of the five gene targets including 16S rRNA, ssrA, secA, rpoB, and groEL. Antifungal susceptibilities were determined by Clinical and Laboratory Standards Institute document (CLSI) M100 broth microdilution methodology. The T. tyrosinosolvens isolate obtained from a 51-year-old immunocompetent woman who was misdiagnosed as pulmonary tuberculosis and treated for nearly 4 years but showed no improvement in symptoms. The correct diagnosis was suspected only when the results of mycobacteria nucleic acid amplification tests were negative. The isolates grows best on blood agar as white, dry and rough colonies, with irregular spreading margins after 24 h of incubation at 37. The performance of groEL gene sequencing for species-level identification of T sukamurella was better than other four genes. The T tyrosinosolvens isolate is resistant to rifampicin (>2 [micro]g/ml), ceftazidime (>32 [micro]g/ ml), ampicillin (16 [micro]g/ml), aztreonam (>128 [micro]g/ml), erythromycin (>8 [micro]g/ml), vancomycin (8 [micro]g/ml), daptomycin (4 [micro]g/ml) and colistin (>8 [micro]g/ml). While it is susceptible to ceftaroline (0.25 [micro]g/ ml), ceftriaxone (1 [micro]g/ml), imipenem (0.25 [micro]g/ml), meropenem (1 [micro]g/ml), linezolid (1 [micro]g/ml), levofloxacin (0.5 [micro]g/ml), moxifloxacin (0.25 [micro]g/ml) and tigecycline (0.25 [micro]g/ml). Based on our and previous study, fluoroquinolones is considered as an excellent antibiotic to treat this uncommon micro-organism. Thus this study points to a possible emergence of T tyrosinosolvens as a significant pathogen cause lung disease which was prone to misdiagnose as pulmonary tuberculosis in the immunocompetent patients. Molecular methods are needed for accurate identification and further molecular characterization of this species. Fluoroquinolone may be a successful oral antibiotic regimen.