Disseminated Mycobacterium kansasii and Salmonella Typhimurium co-infection following iatrogenic immunosuppression: a case report
- 1Department of General Practice, Zhongshan Hospital (Xiamen), Fudan University, Xiamen, 361006 China
- 2Department of General Practice, Zhongshan Hospital, Fudan University, Shanghai, 200032 China
Abstract
Background: Disseminated Mycobacterium kansasii and Salmonella Typhimurium co-infection is exceptionally rare, particularly in patients without overt immunodeficiency. This case describes a unique disease progression and iatrogenic drivers in such co-infections.
Case presentation: A 61-year-old male with uncontrolled diabetes presented with recurrent fever accompanied by axillary lymph node enlargement. Elevated inflammatory markers were noted. Brain magnetic resonance imaging (MRI) revealed a right parietal abscess with subdural empyema. Blood cultures and metagenomic Next-Generation Sequencing (mNGS) of blood and cerebrospinal fluid (CSF) confirmed Salmonella Typhimurium infection. Chest computed tomography (CT) demonstrated bilateral pulmonary inflammation. Contrast-enhanced CT/MRI of the spleen showed splenomegaly with heterogeneous enhancement and diffuse small enhancing nodules. Ultrasound revealed generalized lymph node enlargement, particularly axillary. Right axillary lymph node excision pathology, culture and mNGS confirmed Mycobacterium kansasii. The patient was diagnosed with disseminated Mycobacterium kansasii (lymph nodes, lungs, and spleen) and Salmonella Typhimurium (bloodstream, brain) co-infection. HIV testing was negative, while anti-interferon-γ autoantibodies and interferon-γ levels were within normal ranges. Clinical trajectory suggested initial Mycobacterium kansasii pulmonary and lymphatic infection, followed by Salmonella bacteremia after ingesting raw pig gallbladders. Subsequent immunosuppression (cyclosporine/prednisone) triggered disseminated co-infection (brain, lymph nodes, spleen). Prolonged antimicrobial therapy achieved remission.
Conclusions: This case describes a rare disseminated co-infection with Mycobacterium kansasii and Salmonella Typhimurium, initially presenting with non-tuberculous mycobacterium infection and subsequently complicated by salmonellosis due to raw porcine gallbladder ingestion, with dissemination of both pathogens driven by immunosuppression. It highlights the need for suspicion of atypical pathogens and cautious use of immunosuppressive therapy.
Related
- USF2 deficiency enhances intracellular clearance of Salmonella Typhimurium via xenophagy and LC3-associated phagocytosis.
- Disseminated Mycobacterium genavense presenting as recurrent steroid-responsive mesenteric lymphadenitis
- Disseminated Mycobacterium colombiense Disease in a Person Living with HIV: Diagnostic and Therapeutic Considerations.
- Modular design of Salmonella Typhimurium OMV-based nanovaccines for tunable dual-form polysaccharide antigen delivery
- Gynecomastia in iatrogenic Cushing syndrome.
BibTeX
@article{huang2026disseminated,
title = {{Disseminated Mycobacterium kansasii and Salmonella Typhimurium co-infection following iatrogenic immunosuppression: a case report}},
author = {Cui-Ling Huang and Cheng-Dian Lan and Yao Liu},
journal = {BMC Infectious Diseases},
year = {2026},
month = aug,
doi = {10.1186/s12879-026-14177-7},
url = {https://doi.org/10.1186/s12879-026-14177-7},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - JOUR
TI - Disseminated Mycobacterium kansasii and Salmonella Typhimurium co-infection following iatrogenic immunosuppression: a case report
AU - Cui-Ling Huang
AU - Cheng-Dian Lan
AU - Yao Liu
PY - 2026
DA - 2026/08/06
JO - BMC Infectious Diseases
DO - 10.1186/s12879-026-14177-7
UR - https://doi.org/10.1186/s12879-026-14177-7
AB - Background: Disseminated Mycobacterium kansasii and Salmonella Typhimurium co-infection is exceptionally rare, particularly in patients without overt immunodeficiency. This case describes a unique disease progression and iatrogenic drivers in such co-infections. Case presentation: A 61-year-old male with uncontrolled diabetes presented with recurrent fever accompanied by axillary lymph node enlargement. Elevated inflammatory markers were noted. Brain magnetic resonance imaging (MRI) revealed a right parietal abscess with subdural empyema. Blood cultures and metagenomic Next-Generation Sequencing (mNGS) of blood and cerebrospinal fluid (CSF) confirmed Salmonella Typhimurium infection. Chest computed tomography (CT) demonstrated bilateral pulmonary inflammation. Contrast-enhanced CT/MRI of the spleen showed splenomegaly with heterogeneous enhancement and diffuse small enhancing nodules. Ultrasound revealed generalized lymph node enlargement, particularly axillary. Right axillary lymph node excision pathology, culture and mNGS confirmed Mycobacterium kansasii. The patient was diagnosed with disseminated Mycobacterium kansasii (lymph nodes, lungs, and spleen) and Salmonella Typhimurium (bloodstream, brain) co-infection. HIV testing was negative, while anti-interferon-γ autoantibodies and interferon-γ levels were within normal ranges. Clinical trajectory suggested initial Mycobacterium kansasii pulmonary and lymphatic infection, followed by Salmonella bacteremia after ingesting raw pig gallbladders. Subsequent immunosuppression (cyclosporine/prednisone) triggered disseminated co-infection (brain, lymph nodes, spleen). Prolonged antimicrobial therapy achieved remission. Conclusions: This case describes a rare disseminated co-infection with Mycobacterium kansasii and Salmonella Typhimurium, initially presenting with non-tuberculous mycobacterium infection and subsequently complicated by salmonellosis due to raw porcine gallbladder ingestion, with dissemination of both pathogens driven by immunosuppression. It highlights the need for suspicion of atypical pathogens and cautious use of immunosuppressive therapy.
SN - 1471-2334
ER -