Swollen Necrotic Lymphadenitis Infected with Mycobacterium Paracondontium in an AIDS Patient: a Case Report and Literature Review

Abstract

Background: Non-tuberculous mycobacteria (NTM) are a group of mycobacteria that are commonly found in the environment and can cause disease in humans. The symptoms of NTM infection can be similar to those of tuberculosis, making diagnosis challenging. The morbidity associated with NTM is increasing, and clinical management can be challenging.

Case description: This report details the case of a 32-year-old male who was found to have multiple enlarged and partially necrotic lymph nodes in the neck, axilla, mediastinum, and retroperitoneum. The causative agent was rapidly identified as Mycobacterium paracondontium through pathogen-targeted sequencing (tNGS). After two weeks of treatment with azithromycin, moxifloxacin, rifabutin, and amikacin, the patient's uncomfortable symptoms had resolved, and he is currently undergoing further review.

Conclusion: It is imperative that clinicians remain vigilant for the presence of NTM, particularly those that are rare, given their pervasiveness in the environment. Prompt diagnosis is of paramount importance, and molecular identification techniques represent a crucial tool in this regard. In vitro drug sensitivity testing should be conducted whenever feasible to guarantee the administration of an efficacious treatment regimen.

Keywords: Mycobacterium paracondontium; case report; lymph nodes; non-tuberculous mycobacteria.

Figure 1

The radiographic examination. (A) uneven enhancement of the upper mediastinal paratracheal area with blue arrows indicating localized necrosis within the lesion, approximately 5.51 cm × 4.33 cm in size;(B) The blue arrow indicates that the necrotic lymph node in the center of the retroperitoneal right pararenal area, approximately 2.45 cm × 1.33 cm in size.

Figure 2

Boundaries are clear, morphology is regular, similar to lymph node echogenicity, and internal echogenic corticomedullary-like demarcation is clear, with larger nodules measuring approximately 2.7 cm × 1.1 cm.

Figure 3

The histopathological examination. (A) Antacid staining magnified 400 times shows antacid bacilli, the red arrows indicate antacid bacilli;(B) HE staining magnified 200 times. Few lymph nodes are organized, lymph node structure is unclear, and histiocytes, lymphocytes, and epithelioid cells are seen constituting a non-caseous necrotic granulomatous nodule.