Hepatic nontuberculous mycobacterial granulomas in patients with cancer mimicking metastases: an analysis of three cases

Abstract

Hepatic granulomas caused by nontuberculous mycobacteria (NTM) are an uncommon, insidious, and indolent disease. Making an accurate diagnosis of a hepatic nontuberculous granuloma is challenging because of nonspecific clinical presentations and radiological appearances, especially in patients with a history of malignant tumors, as these lesions may mimic metastases and make a dilemma for decisionmaking in treatment. Herein, we report three cases of hepatic nontuberculous granulomas following operations for malignant tumors, including colon cancer, ovarian adenocarcinoma, and both rectal and renal carcinoma, respectively. Two patients presented with multiple hepatic lesions and the third had a solitary nodule in the liver. Computed tomography (CT) showed low attenuating nodules without early enhancement in the arterial phase but a slight peripheral enhancement in the portal venous phase after the intravenous administration of contrast agent. Magnetic resonance imaging (MRI) showed high signal intensity on T2weighted image, rim enhancement in the venous phase and no contrast agent of Gd-EOB-DTPA uptake in the hepatobiliary phase. The biopsy was performed, and histopathological examinations revealed the chronic granulomas composed of epithelioid histiocytes, inflammatory cells, and Langhans giant cells. The results of nested polymerase chain reaction (PCR) were positive for NTM.

Non‐Tuberculosis Mycobacterium Periprosthetic Joint Infections Following Total Hip and Knee Arthroplasty: Case Series and Review of the Literature

“…NTM is the cause of numerous ailments, the most prevalent of which is lung infection. Additionally, NTM can induce cutaneous and soft tissue infection, musculoskeletal infection, lymphangitis, and disseminated infection 14,15,64 . In a retrospective study of patients with musculoskeletal infections caused by NTM, the most common microorganisms found to cause infections were MAC, M. fortuitum , and M. abscessus 55 .…”

“…Additionally, NTM can induce cutaneous and soft tissue infection, musculoskeletal infection, lymphangitis, and disseminated infection. 14,15,64 In a retrospective study of patients with musculoskeletal infections caused by NTM, the most common microorganisms found to cause infections were MAC, M. fortuitum, and M. abscessus. 55 Our study found that various NTM species were also causative pathogens of PJI.…”

A Rare Case of Disseminated Mycobacterium avium-intracellulare Presenting as Proctitis

“…Nontuberculous Mycobacteria (NTM) are environmental organisms that are opportunistic in nature and under favorable conditions, cause a wide range of diseases ranging from pulmonary to disseminated infections, with the former being the most common [8]. Immune suppression is the typical predisposing factor and includes patients with HIV/AIDS, using immunosuppressive therapy and undergoing solid organ or haematologic transplant [9].…”

Drug Resistance in Nontuberculous Mycobacteria: Mechanisms and Models

“…Structurally, it mainly comprises macrophages, epithelioid cells and multinucleated giant cells, surrounded by a layer of T-lymphocytes [ 75 , 76 ]. Although NTM infections are more commonly associated with alveolar granulomas, disseminated NTM diseases sometimes result in granulomas in other parts of the body like the liver, especially in people with a history of tumors [ 77 ]. These structures present a major challenge to NTM drug therapy in two ways: they limit the penetration of the drugs into the bacteria inside the immune cells, and the anoxic conditions in the granuloma center promote physiological and morphological states that make them more tolerant [ 41 ].…”