A 61-year-old male with diabetes mellitus, non-Hodgkin's lymphoma after chemotherapy, and chronic adrenal replacement therapy presented with a persistent cough of 3-month duration. Chest CT revealed paramediastinal infiltrates. Weakly acid-fast bacilli were detected in sputum, and treatment with ethambutol, rifampin, and clarithromycin was given for presumed MOTT infection. Although the patient reported strict compliance with drug therapy for 3 weeks, no improvement was noted. Nocardia spp. was isolated from sputum culture. DNAwas extracted from bacterial colonies. A 439-bp fragment encompassing the hsp-65 gene was PCRamplified and subsequently digested with BstEII and HaeIII endonucleases. Bacterial DNAwas also PCR-amplified using a primer pair specific for conserved regions of 16S rRNA. PCR-RFLP analysis revealed a restriction pattern compatible with that of Nocardia nova. This identification was ultimately confirmed as N. nova, 99% homology, based on BLAST analysis of the bacterial 16S rRNA sequence. The isolate was sensitive to erythromycin. The patient received trimethoprim/sulfamethoxazole and a gradual clinical and radiological improvement was observed. N. nova may account for about 20% of Nocardia isolates identified as N. asteroides [1]. Sequence-based identification contributes to rapid and accurate separation of N. nova from other related species, such as N. farcinica, which may be resistant to numerous antimicrobial agents. The advent of