Pulmonary nocardiosis in kidney transplant recipients: A case report and analysis of 60 published cases

Background

Pulmonary nocardiosis (PN) is a rare life-threatening opportunistic infection, particularly involving immunocompromised patients, including kidney transplant recipients (KTRs). This study aimed to present a case of PN in a KTR and review published cases to describe the demographic, clinical, and treatment characteristics of PN in this population.

Methods and results

Here, we report a case of PN in a 68-year-old diabetic patient with a history of kidney transplantation. Upon admission, antimicrobial and antifungal therapy was initiated empirically, considering a chest CT suggestive of fungal infection and pneumonia. In further evaluations, Nocardia was isolated from bronchoalveolar lavage cultures. After PN diagnosis and tailoring antibiotic regimen to Trimethoprim-sulfamethoxazole (TMP-SMX), the patient showed significant improvement. This study also reviewed the English-language literature published from 1981 to 2023 about PN in KTRs and described various characteristics of 60 similar patients. Moreover, antibiotics and the type of combination therapy used for treatment and outcomes were discussed. The median time of onset of PN after kidney transplantation was 182 days (70.5–730). Lung was the only affected organ by Nocardia in 37 patients, while in 13 patients, simultaneous involvement of the lungs and the brain was reported. Fever (74.5 %) was the most reported symptom, followed by cough (50.9 %), headache (41.8 %), and dyspnea (30.9 %). TMP-SMX was the most frequently prescribed antibiotic, having been provided in 32 patients (59.3 %). Other antibiotics included carbapenems, cephalosporins, amoxicillin/clavulanic acid, etc. Furthermore, 38 patients (70.4 %) received combination therapy, whereas 16 patients (29.6 %) received a single antibiotic agent. Lastly, the outcomes of 55 patients were reported. While the majority (81.8 %) were successfully treated, 10 patients (18.2 %) expired due to nocardiosis.

Conclusion

Physicians should consider the diagnosis of PN in the differential diagnosis of KTR presenting with pneumonia, especially within the first six months post-transplant, when the risk of nocardiosis is elevated due to intensive immunosuppression.