To be immunocompromised is defined as state of impaired or dysfunctional immune system, precisely a system that is unable to defend the organism against external pathogens. Immunodeficiency in a patient can develop in various ways, and depending on the etiology, it has a different clinical presentation. The most concrete example of immunodeficiency in the world is the one caused by the human immunodeficiency virus (HIV), which has become a global problem and brings with itself a wide variety of conditions and opportunistic infections. An immunocompromised patient has an increased tendency to develop an infection caused by a pathogen compared to a patient with a functional immune system. Various opportunistic agents from the group of fungi, parasites, bacteria and viruses attack immunosuppressive hosts. Because of the absence of a defense system, pathogens multiply faster and can more easily develop inflammatory and other conditions, with involvement of the neurological, respiratory and other organ systems. During the Covid-19 virus pandemic, immunocompromised patients represented a significant medico-sociological problem due to their vulnerability. The use of appropriate radiological methods plays an important role in the early detection and diagnosis of various infectious and other diseases that are characteristic for immunocompromised patients.