*Purpose: Nocardiosis is an opportunistic infection occasionally seen after solid organ (SOT) and hematopoietic stem-cell transplantation. Treatment is challenging due to the limited number of oral agents, drug intolerance, organism resistance, toxicity and need for prolonged therapy.

*Methods: Linezolid (LZD) and tedizolid (TZD) both have demonstrated excellent in vitro activity against Nocardia species. However, long-term use of LZD is often prohibited by high rates of hematological and mitochondrial toxicity (ie, myelosuppression, lactic acidosis, and peripheral neuropathy). Conversely, long-term therapy with TZD may be better tolerated, but evidence is scarce. Herein, we report the successful use of long-term TZD as the cornerstone of nocardiosis therapy in four transplant patients. (Table 1).

*Results: A 51-year-old woman underwent a deceased-donor kidney transplantation (KT). Six months later she developed fever, chills, and cough. Imaging showed diffuse, patchy ground-glass opacities with focal consolidation of the left upper lobe. Blood and sputum cultures grew Nocardia nova. She was started on trimethoprim-sulfamethoxazole (TMP-SMX) and LZD. Due to intolerance, she was switched to azithromycin and TZD which she has tolerated well for 11 months into a planned year-long therapy. A 54-year-old male underwent a living, unrelated-donor KT. 26 months after transplant he developed a headache, confusion, and altered gait. Imaging showed a new left occipital brain abscess. Intraoperative cultures grew Nocardia paucivorans. He was initially treated with ceftriaxone and TMP-SMX. Due to hyperkalemia and renal failure, he continued ceftriaxone with TZD with a plan for 1 year of therapy. A 54-year-old male underwent an allogeneic stem cell transplant (SCT). Seven months later he developed a large pleural effusion with cultures positive for Nocardia veterana. He received empiric TMP-SMX and LZD. Due to side effects, his antimicrobials were changed, and he successfully completed treatment with TMP-SMX and TZD. A 60-year-old male underwent allogeneic SCT. Eight months after transplantation he developed fever and cough. Chest imaging revealed numerous pulmonary nodules. Pulmonary and blood cultures grew Nocardia cyriacigeorgica. Initial broad-spectrum antibiotics were changed to TMP-SMX and TZD which he has continued with clinical improvement.

*Conclusions: All patients responded to therapy appropriately and tolerated TZD well. We postulate a potential role of TZD in treatment of nocardiosis in transplant recipients.

« Back to 2020 American Transplant Congress