Abstract: SA-PO1171
An Elusive Pathogen: Disseminated Mycobacterium malmoense in a Kidney Transplant Recipient
Session Information
- Transplantation: Clinical - Infectious Diseases
October 24, 2026 | Location: Exhibit Hall A, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Transplantation
- 2002 Transplantation: Clinical
Author
- Chilton, Merideth Brooke, University of Utah Health, Salt Lake City, Utah, United States
Introduction
In kidney transplant recipients, non-tuberculosis mycobacterial infection is a rare but serious opportunistic infection. It can present with non-specific symptoms such as fever, respiratory symptoms, and night sweats. These infections have high mortality rates in transplant patients despite treatment, and timely diagnosis is important to improve patient outcomes.
Case Description
A 62-year-old man with past medical history of ESRD status post living donor kidney transplant 3/2021 presented to the ER with about 4 weeks of fatigue, cough, and night sweats. CT chest showed a right upper lobe consolidation and a quantiferon gold was negative. He was discharged with Augmentin, doxycycline, and follow up with infectious disease in a week. At follow-up, he was hypotensive and was referred to the hospital for admission.
Workup on admission included respiratory bacterial, fungal, and AFB cultures, CT chest, and viral serologies. CT chest showed an increase in the extent of the right upper and middle lobe consolidation with ground glass tree-in-bud opacities as well as central cavitation. Sputum cultures and smear were positive for AFB and the appearance was thought to be suggestive of non-tuberculosis mycobacteria. After discharge, the AFB speciated as Mycobacterium malmoense and the patient was started on a 3-drug regimen with Ethambutol, Rifampin, and azithromycin. He continued to have symptoms and was eventually readmitted with worsening cough, fever, and night sweats. CT chest at this time showed worsening lymphadenopathy and new nodular opacities. Stool cultures were positive for AFB, though this may have been secondary to ingestion of sputum rather than infection. He was briefly started on amikacin despite concern for nephrotoxicity given the concern for disseminated infection, though this was discontinued after he developed an AKI. After being stabilized, the patient was again discharged. Since then, cultures drawn during his first hospitalization resulted as positive for AFB which have failed to clear on subsequent cultures.
Discussion
In this patient, mycobacterial disease was initially thought to be unlikely given his negative quantiferon gold, so treatment was unfortunately delayed. Given the significant mortality in patients with non-TB mycobacterial disease, it is important to keep a high index of suspicion for early diagnosis and treatment to prevent poor patient outcomes.