Comparative Characteristics of Granulomatous Lesions in the Lungs in Tuberculosis, Talcosis, and Cryptococcosis in Patients with HIV Infection/AIDS

Abstract

Objrctive — to refine the process of differential diagnosis of morphological and immunohistochemical manifestations of granulomatous inflammation in the lungs of patients with tuberculosis, cryptococcosis and talcosis in conjunction with infection caused by the human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). Additionally, to compare the morphological features of inflam­matory cell reactions. Materials and methods. A retrospective cohort analysis of 400 medical records of hospitalized patients was conducted from 2010 to 2022. Based on inclusion criteria, 75 patients with laboratory-confirmed HIV infection, aged 25 to 75 years, were selected. Protocols of pathological studies were analysed, histological specimens were reviewed, and additional investigations were conducted. Depending on clinical data and autopsy results, patients were divided into three groups: 30 with tuberculosis in conjunction with HIV infection/AIDS, 25 with talc granulomatosis and HIV infection/AIDS and 20 with cryptococcosis in conjunction with HIV infection/AIDS. General morphological, histochemical and immunohistochemical features of lung lesions, as well as the nature and manifestations of the inflammatory cell reaction, were determined using standard histological staining (hematoxylin and eosin), polarization microscopy, histochemical methods (van Gieson staining, PAS reaction) and immunohistochemical analysis (deter­mination of CD4, CD8, CD68, CD20 marker expressions). Results and discussion. The pathomorphological characteristics of lung lesions in groups 1 and 3 are polymorphic and represented by multiple foci of necrosis, focal fibrosis, a weak inflammatory cell reaction, as well as the accumulation of an alteration agent, in group 2 — in the form of an inflammatory cell reaction with the formation of a granulomas. Weak small-focal diffuse expression of CD4 and CD8 markers was determined in all studied samples, different large-focal expression of CD20 and CD68 markers was observed, localized mainly around the inclusion talc in group 2. Conclusions. The application of a comprehensive approach (histological, histochemical, immuno­histochemical investigation and polarization microscopy) in diagnosing granulomatous lung lesions in patients with HIV infection/AIDS enhances the verification of the etiological factor and expands diagnos­tic capabilities. The spectrum of morphological changes in patients with granulomatous lung lesions is polymorphic and depends on various factors. Significant differences are observed in the manifestations of alterative-necrotic, fibrotic changes and immune reactions both within and between groups, justifying the need for an individualized approach in the diagnostic and therapeutic process.