Nocardia farcinica as a cause of chronic meningitis - case report

Nocardia acididurans sp. nov., an acid-tolerant actinobacterium isolated from bio-fertilizer of Musa species

A novel acid-tolerant actinobacterium (strain LPG 2^T), which formed fragmented substrate mycelia, was isolated from bio-fertiliser of Musa spp. collected from Lampang Province, Thailand. Its morphological and chemotaxonomic properties, e.g., the presence of mycolic acid and MK-8 (H_4ω-cycl) in the cells, showed that strain LPG 2^T was a member of the genus Nocardia. 16S rRNA gene sequence analysis revealed that this strain was closely related to Nocardia otitidiscaviarum NBRC 14405^T (98.7 %). The low average nucleotide identity-blast and digital DNA-DNA hybridization values (<78.6 and <24.0 %, respectively), and several phenotypic differences between strain LPG 2^T and its related Nocardia type strains, indicated that the strain merits classification as representing a novel species of the genus Nocardia, for which we propose the name Nocardia acididurans sp. nov. The type strain is LPG 2^T (=TBRC 11242^T=NBRC 114293^T).

Nocardia farcinica Brain Abscess in an Immunocompetent Host With Pulmonary Alveolar Proteinosis: A Case Report and Review of the Literature

A 55-year-old immunocompetent male presented with new-onset seizures and acute respiratory failure requiring intubation and a stay in the medical intensive care unit. Magnetic Resonance Imaging (MRI) of the brain revealed ring-enhancing lesions, and Computed Tomography (CT) chest showed ground-glass opacity. The patient underwent craniotomy and bronchoscopy, followed by culture of the purulent aspirate from lesions in the brain and bronchoalveolar lavage (BAL). After extensive infectious workup, the patient was diagnosed with a Nocardia farcinica brain abscess plus underlying pulmonary alveolar proteinosis (PAP). Based on a recommendation from an infectious disease expert, the patient was treated with trimethoprim-sulfamethoxazole (TMP/SMX).

This case highlights the importance of understanding that, though rare, infections such as nocardiosis can present in immunocompetent patients and cause severe morbidity.

Asymptomatic cerebral abscesses after pleuropulmonary Nocardia farcinica infection

We report the case of a 68-year-old man with long-term receipt of steroid therapy who was diagnosed with cerebral abscesses and pulmonary nocardiosis. This patient displayed only respiratory symptoms. Confirmation of Nocardia farcinica species was achieved by specific PCR sequencing of the 16S ribosome RNA in bronchoalveolar lavage cultures. Cerebral magnetic resonance imaging revealed abscesses. Antibiotic therapy with trimethoprim/sulfamethoxazole was prescribed given the results of susceptibility tests and was maintained for 12 months, with no evidence of relapse afterwards.