Solitary Pulmonary Nodule Due to Mycobacterium kansasii

Abstract

A 46-year-old man with no past history of underlying disease was admitted to our hospital for examination of abnormal chest shadow on chest radiograph. He had no respiratory symptoms on admission. Chest radiograph showed a solitary nodule (35×20 mm) in the left upper lung field. On chest CT, this nodule in the left upper lobe (S 1+2 ) did not demonstrate calcification, the margin was clear but irregular, and there was pleural indentation. The solitary nodule was strongly positive on PET/CT. Therefore, we suspected primary lung cancer. Because we could not establish the diagnosis by bronchoscopic examination, video-assisted thoracoscopic surgery (VATS) was performed. Histological diagnosis of the solitary nodule demonstrated epitheloid granuloma with caseous necrosis. Smear test of the resected tissue was positive for acid-fast bacilli and culture was positive for mycobacteria, which was identified as Mycobacterium kansasii. There are a few case reports of solitary nodule due to M. kansasii.

PET/CT in nononcological lung diseases: current applications and future perspectives

“…Similar to tuberculosis, NTM could have a broad range of radiological patterns including nodular or pseudo-nodular lesions, parenchymal consolidation, cavitary lesions, pleural thickenings, and pleural effusions, or a mixed pattern [33][34][35].…”

Solitary pulmonary caseating granulomas: A 5-year retrospective single-center analysis

“…In the present study, 1 of the patients who received anti-tuberculosis treatment developed DIH, and hyposensitization therapy was undertaken, which proved efficacious. Regarding the management of NTMPNs, a previous study documented the case of a patient with an SPN caused by M. kansasii , who was followed up without anti-tuberculosis therapy following VATS and remained free from recurrence (28). None of the 8 patients with NTMPNs in the present study (excluding the 3 patients with NTMPNs associated with concurrent lung cancer) received anti-tuberculosis therapy, and no relapse was detected in any of these patients during the course of follow-up for >1 year.…”

PulmonaryMycobacterium kansasiiInfection Mimicking Malignancy on the18F-FDG PET Scan in a Patient Receiving Etanercept: A Case Report and Literature Review

“…Activated inflammatory cells have markedly high metabolic activity with increased glucose uptake and glycolysis process, and avid FDG uptake is undoubtedly the rule in inflammatory tissues. Thus, benign conditions with positive 18 F-FDG-PET scan findings have been reported in an array of infections, inflammatory, or granulomatous diseases (Table 1), but the list is not exhaustive [4, 15–18]. …”

“…There were two other published case reports of nonpulmonary M. kansasii infections (skin lesions and olecranon bursitis) in patients treated with anti-TNF-alpha agents (Table 2) [19, 20]. A case of 18 F-FDG PET-positive solitary pulmonary nodule from M. kansasii infection in an immunocompetent host was reported in the literature [18]. …”