[Histological differential diagnosis of granulomatous lung diseases (Part II)]

[Features of granulomatous inflammation in helminthiasis, mycoses and human protozoal diseases in forensic medical practice]

THE AIM OF THE STUDY

Is to draw the attention of forensic experts and histologists to the problem of infectious diseases occurring with the formation of granulomas. Was reviewed the general patterns of granulomatous diseases, as well as the peculiarities of pathomorphosis in helminthiasis (schistosomiasis, paragonimiasis, onchocerciasis, dirofilariasis, ascariasis, cysticercosis), mycoses (cryptococcosis, chromomycosis, coccidioidosis) and protozoal diseases, toxosomes. The article includes photomicrographs from the authors' personal archive, including those collected during their work in African countries Text is based on scientific data from articles, monographs, educational literature, personal experience and cases of forensic medical practice.

[Pathological anatomy of tuberculosis in the presence of human immunodeficiency virus infection]

Tuberculosis occupies a leading position among secondary infections in the structure of mortality in HIV-positive patients. Moreover, the concurrence of these diseases frequently makes a morphological diagnosis most difficult due to the atypical course of tuberculosis (TB) in the presence of immunosuppression.

AIM

to assess the clinical and morphological characteristics of concurrent TB/HIV infection.

MATERIAL AND METHODS

An autopsy material obtained from the S.P. Botkin Clinical Infectious Diseases Hospital (CIDH) in 2018 was analyzed. Eight samples stained with hematoxylin and eosin, Ziehl-Neelsen carbol-fuchsin, auramine-rhodamine were thoroughly examined, followed by fluorescent microscopy; an immunohistochemical (IHC) study was performed.

RESULTS AND DISCUSSION

736 autopsies made at the S.P. Botkin CIDH in 2018 revealed 357 deaths from HIV infection; 86 (24%) cases of which were caused by concurrent HIV/TB infection. All the cases showed an extremely diverse and heterogeneous pattern that considerably differed from that of classical granulomatous inflammation in tuberculosis. Ziehl-Neelsen staining could demonstrate single clusters of acid-resistant bacteria with a total of not more than 1000 in the specimen of predominantly rod-shaped bacteria. Auramine-rhodamine staining revealed focal clusters of mycobacteria with a total of 1000 to 2000 in the specimen of predominantly rod-shaped and coccoid bacteria. An IHC study identified clusters of mycobacteria with a total of more than 2000 in the sample, which were characterized by a moderate variety of shapes: rods, cocci, granules, clavate, and branched ones. Mycobacteria were present extracellularly in all the studied cases.

CONCLUSION

Tuberculosis holds the most important place in the pattern of causes of death in HIV infection, accounting for 24%. The lifetime diagnosis of tuberculosis remains not entirely satisfactory. The alterative component of inflammation more often predominates, although without completely losing the ability to form granulomas. The concurrence of different morphological forms of tuberculosis makes it highly desirable to clarify and/or supplement the existing classifications. None of the methods used to detect Mycobacterium tuberculosis in the tissues could reveal the intracellular localization of the pathogen. Most mycobacteria had a typical rod-shaped morphology.