This case underscores that NTM infection should be considered in the differential diagnosis of unexplained chronic gastrointestinal symptoms and highlights the pivotal role of modern molecular techniques in reaching a precise diagnosis.
Abstract
Background
Non-tuberculous mycobacteria (NTM) are important opportunistic pathogens that most commonly infect the lungs. Primary involvement of the gastrointestinal tract-especially the small intestine-is exceedingly rare, and small-bowel infection caused by Mycobacterium kansasii (M. kansasii) has seldom been reported.
CASE PRESENTATION
We describe an extremely rare case of primary small-intestinal M. kansasii infection in an immunocompetent young man who presented with prolonged chronic diarrhea and fever. After an extensive but unrevealing diagnostic work-up, the etiology was finally established by microbial metagenomic sequencing of tissue obtained by double-balloon endoscopy. Building on the initial regimen of ethambutol hydrochloride, rifampicin, and clarithromycin-and with subsequent antibiotic adjustments tailored to the patient's evolving symptoms-clinical symptoms resolved completely, and follow-up endoscopy showed mucosal improvement.
Conclusion
This case underscores that NTM infection should be considered in the differential diagnosis of unexplained chronic gastrointestinal symptoms and highlights the pivotal role of modern molecular techniques in reaching a precise diagnosis. Detailed analysis of the case together with a review of the literature aims to raise clinicians' awareness and improve management of this rare entity.
The case of a 48-year-old patient recently diagnosed with HIV and a CD4 lymphocyte count of less than 50 cells/ uL, who consulted for prolonged fever without apparent focus, highlights the importance of considering nocardiosis in the differential diagnosis of prolonged fever with multiple deep lesions in immunocompromised patients.
María Trinidad Pennini Guelfi, Camilo Martínez, Ana De Lajonquiere et al.· Medicina· 0 citations
This case underlines the importance of considering brucellosis in febrile patients with livestock exposure, even in non-endemic settings, and presents a rare and severe respiratory form of brucellosis in a patient with occupational exposure to livestock.
Ondrej Zahornacký, Š. Porubčin, Alena Rovňáková et al.· The Egyptian Journal of Inte...· 0 citations
The diagnosis and treatment of Mycobacterium abscessus infections present significant challenges, especially in the rare cases of extrapulmonary involvement in pediatric patients. These cases are characterized by diagnostic difficulties, limited therapeutic options, scarce clinical experience, and a lack of evidence-based treatment guidelines. This article reports on a 6-year-old child who experienced fever and abdominal pain. Metagenomic next-generation sequencing (mNGS) facilitated the rapid and accurate identification of Mycobacterium abscessus as the causative pathogen. Under a standardized full-course protocol, an individualized therapy regimen (that includes Imipenem, Azithromycin, and Linezolid) led to favorable clinical outcomes. Through the analysis of this successfully treated case, we aim to derive clinical insights and identify potential limitations, with the goal of exploring effective diagnostic and therapeutic approaches for pediatric patients with non-tuberculous mycobacterial (NTM) infections in the future.
Linlin Zhang, Dixi Huang, Jie Song et al.· Frontiers in Pediatrics· 0 citations
ABSTRACT
Pulmonary nocardiosis is an uncommon but potentially serious infection caused by aerobic actinomycetes of the genus Nocardia. It predominantly affects individuals with impaired immunity or underlying structural lung disease, but can also occur in apparently immunocompetent hosts. The clinical and radiological features often overlap with tuberculosis and fungal infections, particularly in endemic regions, leading to frequent misdiagnosis and delay in appropriate therapy. We present a series of three patients with microbiologically confirmed pulmonary nocardiosis, each representing different clinical backgrounds. The first case involved a middle-aged male with poorly controlled diabetes mellitus presenting with chronic cough and bilateral pulmonary infiltrates. Imaging revealed patchy peribronchial opacities, and bronchoalveolar lavage (BAL) demonstrated filamentous, weakly acid-fast organisms on modified acid-fast staining. The second case was an elderly female with underlying bronchiectasis who presented with increased cough and expectoration; imaging showed bronchiectatic changes with superimposed infiltrates, and BAL confirmed Nocardia infection. The third case involved an elderly male with recent immunosuppressive therapy who presented with acute respiratory symptoms and radiological evidence of multifocal consolidation; microbiological evaluation confirmed nocardiosis. All patients were treated with appropriate antimicrobial therapy, including trimethoprim-sulfamethoxazole as the backbone, with additional agents such as imipenem or linezolid in selected cases. Clinical improvement was observed in patients who adhered to therapy, with symptomatic relief and partial radiological resolution on follow-up. This case series underscores the varied clinical presentation and imaging spectrum of pulmonary nocardiosis. Diabetes mellitus, structural lung disease, and immunosuppressive therapy emerged as key predisposing factors. The condition often mimics tuberculosis or bacterial pneumonia, making microbiological confirmation using modified acid-fast staining crucial. Early diagnosis and prompt initiation of appropriate therapy significantly influence patient outcomes. Pulmonary nocardiosis should be considered in patients with nonresolving pulmonary infiltrates, especially in the presence of risk factors such as diabetes, bronchiectasis, or immunosuppression. A high index of suspicion, combined with timely microbiological diagnosis and appropriate antimicrobial therapy, is essential to improve prognosis and reduce morbidity.
N. Raja, V. Jereen, A. Arthi et al.· Annals of African medicine· 0 citations
Histoplasmosis is an endemic mycosis in certain regions of Brazil and represents a rare opportunistic infection in solid organ transplant recipients. This report describes the case of a 68-year-old female liver transplant recipient (due to Caroli disease) who presented with abdominal pain, nausea, vomiting, and a distended, tender abdomen. Abdominal computed tomography revealed parietal thickening of the bowel wall, and colonoscopy identified polymorphic ulcers and ileocecal stenosis. Given the suspicion of tuberculosis, chest computed tomography was performed, which demonstrated pulmonary opacities. Although testing for acid-fast bacilli was negative, fungal staining was positive for Histoplasma capsulatum. Antifungal therapy with amphotericin B was initiated; however, due to clinical refractoriness, surgical intervention was required, including ileocecal resection with ileo-ascending anastomosis. A reoperation was performed due to postoperative complications, resulting in the creation of a terminal ileostomy. Following this intervention, the patient showed clinical improvement and tolerated an oral diet. This case highlights an atypical presentation of disseminated histoplasmosis with pulmonary and intestinal involvement, culminating in intestinal subocclusion in a late-stage liver transplant recipient. It underscores the importance of considering histoplasmosis in the differential diagnosis of immunosuppressed patients and the need for early investigation and treatment.
Fernando Camargo Fernandes, Pedro Cunha de Freitas Meirelles Meira, Amanda Pinter Carvalheiro da Silva Boteon et al.· Einstein· 0 citations
Non-tuberculous mycobacterium is a prevalent pathogen that-despite myriad systemic presentations, particularly among immunocompromised hosts-rarely presents in the periocular and adnexal region. The authors present here the first reported case of pyomyositis caused by Mycobacterium avium complex in an immunocompetent patient presenting with progressive, insidious proptosis, found to have a "cold abscess" in the inferior rectus warranting surgical drainage and prolonged medical treatment. In addition to its novelty, this case reviews pyomyositis of the extraocular muscles and NTM infections in the periocular and adnexal region. This case underscores that non-tuberculous mycobacterium infections can affect immunocompetent individuals, despite their typical association with immunocompromised states. Moreover, pyomyositis-although rarely caused by non-tuberculous mycobacterium-can also occur in immunocompetent patients. Ultimately, these patients require surveillance by both ophthalmologists and infectious disease specialists to ensure complete eradication of this fastidious organism.
Leo Hall, H. J. Kim, Robert C. Kersten· Ophthalmic Plastic and Recon...· 0 citations
