Immune Reconstitution Inflammatory Syndrome Secondary to Mycobacterium kansasii Infection in a Kidney Transplant Recipient

Varying clinical presentations of nontuberculous mycobacterial disease : Similar to but different from tuberculosis

The incidence rate of pulmonary nontuberculous mycobacterial disease (PNTMD) in Japan is the highest among major industrialized nations. Although the typical clinical course and radiological manifestations of PNTMD are different from those of pulmonary tuberculosis (TB), confusion about these mycobacterial diseases leads to a diagnostic pitfall. Diagnostic challenges include the coexistence of Mycobacterium tuberculosis (MTB) and nontuberculous mycobacteria (NTM), false positives for NTM in MTB nucleic acid amplification tests, microbial substitution, and abnormal radiological manifestations caused by NTM. Features of extrapulmonary NTM diseases, such as pleurisy, vertebral osteomyelitis, and disseminated disease, are different from the corresponding tuberculous diseases. Moreover, the immunological background of the patient (status of human immunodeficiency virus infection with or without antiviral therapy, continuation or discontinuation of immunosuppressive therapy, use of immune checkpoint inhibitor, pregnancy and delivery, etc.) influences the pathophysiology of mycobacterial diseases. This review describes the varying clinical presentations of NTM disease with emphasis on the differences from TB. J. Med. Invest. 68 : 220-227, August, 2021.

Mycobacterium abscessus Gastric Band Infection Complicated by Immune Reconstitution Inflammatory Syndrome and Cured in the Context of Allogeneic Hematopoietic Stem Cell Transplantation

We present a case of abdominal gastric band-associated Mycobacterium abscessus infection, manifesting after the onset of acute myeloid leukemia, complicated by immune reconstitution inflammatory syndrome (IRIS), and cured while receiving an allogeneic hematopoietic stem cell transplant. IRIS should be considered in less classical situations where there is unexplained clinical deterioration.

Management of Mycobacterium Other than Tuberculosis in Solid Organ Transplantation

Mycobacteria other than tuberculosis are important pathogens to consider in solid organ transplant recipients. Delay in recognition and treatment may incur significant morbidity and mortality. Management of mycobacteria other than tuberculosis requires a knowledge of treatment specific for each species and drug-drug interactions between antimicrobial and immunosuppressive drugs. Therapy in solid organ transplant can be prolonged and may require a reduction in immunosuppression to improve outcomes.

Laryngeal Inflammatory Pseudotumour Secondary to Mycobacterium kansasii

BACKGROUND

Inflammatory pseudotumours (IPT) are rare benign tumours characterised by spindle-shaped histiocyte proliferation often mimicking a soft tissue sarcoma. They can occur in different parts of the body and various aetiological factors have been proposed. To our knowledge this is the first case report of IPT of the larynx caused by mycobacterial disease.

CASE REPORT

We report a case of IPT of the larynx in an immunocompromised 81-year-old lady presenting with stridor and dysphagia with known disseminated Mycobacterium kansasii of the lungs.

CONCLUSION

This case demonstrates both the clinical and histological difficulties in making the diagnosis of IPT. A high index of suspicion is needed, and the importance of a multidisciplinary approach in the work-up, diagnosis, and management is highlighted.

How can we improve the outcome for transplant patients with nontuberculous mycobacterial infections?

Nontuberculous mycobacteria (NTM) are environmental organisms that are rapidly emerging as pathogens in the transplant population. The prevalence of infection in transplant recipients remains unknown. While guidelines exist for treatment of NTM, neither the American Thoracic Society, the Infectious Diseases Society of America, nor the British Thoracic Society guidelines dictate the approach needed for transplant recipients. Here, we summarize risk factors, important diagnostic and treatment facts, and preventive measures to be taken to help improve outcomes of those infected with NTM infections.

Paradoxical Reactions and the Immune Reconstitution Inflammatory Syndrome

In HIV-infected individuals, paradoxical reactions after the initiation of antiretroviral therapy (ART) are associated with a variety of underlying infections and have been called the immune reconstitution inflammatory syndrome (IRIS). In cases of IRIS associated with tuberculosis (TB), two distinct patterns of disease are recognized: (i) the progression of subclinical TB to clinical disease after the initiation of ART, referred to as unmasking, and (ii) the progression or appearance of new clinical and/or radiographic disease in patients with previously recognized TB after the initiation of ART, the classic or "paradoxical" TB-IRIS. IRIS can potentially occur in all granulomatous diseases, not just infectious ones. All granulomatous diseases are thought to result from interplay of inflammatory cells and mediators. One of the inflammatory cells thought to be integral to the development of the granuloma is the CD4 T lymphocyte. Therefore, HIV-infected patients with noninfectious granulomatous diseases such as sarcoidosis may also develop IRIS reactions. Here, we describe IRIS in HIV-infected patients with TB and sarcoidosis and review the basic clinical and immunological aspects of these phenomena.