Challenges in the morphological diagnostics of infectious lung diseases among HIV-infected patients: a case-series study

Abstract

HIV-infection is a long-term infectious disease, characterized by deterioration of the immune system and it is often complicated by the development of opportunistic diseases, mainly of infectious origin. HIV-associated infections become generalized in the late stages of the disease and often may combine, that makes challenges in the diagnosis of these diseases. Differential morphological diagnosis of HIV-associated lung infections is quite complex. Most frequently, there is the need to differentiate between tuberculosis, bacterial or septic pneumonia, cytomegalovirus lung lesions, and deep mycoses. The aim. To demonstrate the expediency and necessity to apply special complex morphological methods in HIV-infected patients with secondary lung lesions using the series of clinical cases as an example. Materials and methods. The case series consisted of 7 cases with discordance between the clinical-radiologic, laboratory data and histological conclusions. Of these, there were 5 cases of life-time and 2 autopsy diagnoses. All the clinical and laboratory data of these cases were retrospectively analyzed, and a number of additional special histological examinations were performed. The Ziehl–Neelsen and fluorescent methods, Gomori–Grocot and alcian blue-PAS staining as well as immunohistochemical examinations were used for the detection of mycobacterial antigens with different antibodies to M. tuberculosis. Results. The case series of initial morphological misdiagnosis or indeterminate histological diagnosis was revealed among hospitalized HIV-infected patients. Clinical data did not provide an accurate diagnosis of pulmonary pathology. According to the traditional histological examination, a tuberculous process was diagnosed in 3 cases, a chronic granulomatous process – in 2 cases, but without specifying the etiology. In two cases of autopsy, pneumocystis pneumonia was suspected in combination with other infections. Additional morphological examination with using 2–6 special methods made it possible to determine the correct diagnosis. In 2 cases of provisional diagnosis of tuberculosis, invasive cryptococcosis and “pneumonia in a drug user” were revealed. Cryptococcosis and pneumocystis pneumonia were detected in 2 cases with an unspecified process. In the autopsy cases, the diagnosis of pneumocystis pneumonia was ruled out, while viral-bacterial pneumonia and tuberculosis associated with cytomegalovirus infection were detected. Conclusions. The presented factual material demonstrates the principal importance of using a comprehensive morphological examination in cases of lung inflammatory processes in HIV-infected patients. Clinical patient data, namely HIV-status at the time of diagnostic procedures as well as radiological and microbiological findings serve as a substantial aid in the diagnosis.