A case of pulmonary Mycobacterium heckeshornense infection in a healthy Japanese man

Diagnosis of pulmonary Mycobacterium heckeshornense infection using matrix-assisted laser desorption ionization time-of-flight mass spectroscopy

“…Despite persistent sputum isolation of the species and discontinuation of the short-course antibiotic treatment due to cutaneous drug eruptions, the patient reported in the present study remained stable. In parallel with our case report, previously reported radiographic findings of pulmonary M. heckeshornense infection include upper lobe-dominant locations of cavitary, nodular, and/or infiltrative lesions [4] , which make it difficult to distinguish from infection caused by other Mycobacterium species. However, MALDI-TOF MS is useful for the diagnosis of M. heckeshornense infection.…”

“…M. heckeshornense is a rare, slow growing, scotochromogenic organism that was firstly isolated from patients with pulmonary infection [1] . Previous cases of M. heckeshornense infection have reported the involvement of the lungs, bones, muscles, and lymph nodes [1] , [2] , [3] , [4] , [5] . The diagnosis of M. heckeshornense infection is somewhat problematic.…”

“…The diagnosis of M. heckeshornense infection is somewhat problematic. First, M. heckeshornense has a very slow growth rate [1] and often grows only in MGIT, not on solid medium [4] . Second, M. heckeshornense can be misidentified as Mycobacterium.…”

“…xenopi in a commercially available DNA–DNA hybridization kit [3] , [5] ; therefore, DNA sequence analysis of 16S rRNA, rpo B, and hsp 65 is required for identification. However, MALDI-TOF MS systems have started being used commercially and are reliable in identifying M. heckeshornense species [3] , [4] . Some previous studies have reported that M. heckeshornense is resistant to isoniazid but susceptible to rifampicin, ethambutol, clarithromycin, streptomycin, and levofloxacin [4] , [5] .…”

“…However, MALDI-TOF MS systems have started being used commercially and are reliable in identifying M. heckeshornense species [3] , [4] . Some previous studies have reported that M. heckeshornense is resistant to isoniazid but susceptible to rifampicin, ethambutol, clarithromycin, streptomycin, and levofloxacin [4] , [5] .…”