[Abdominal manifestations in immunocompromised patients]

Abdominal infections or tumors in the immunocompromised host are both common in AIDS but uncommon in transplant recipients. The role of diagnostic imaging modalities differs in the patients with specific symptoms such as dysphagia, diarrhea, malabsorption and jaundice and in the patients with aspecific clinical findings such as fever, weight loss, superficial lymphadenopathies and abdominal pain. In the former patients, the symptoms suggest a disease of one or more alimentary tracts, in which case radiology is ancillary to clinics and endoscopy plays the leading role to make the diagnosis. However, X-ray barium studies yield valuable information on different types of infections--e.g., Candida, Cytomegalovirus, mycobacterium avium intracellulare and Cryptococcus infections--in Kaposi's sarcoma and in gastrointestinal lymphoma. In these cases CT findings may suggest the diagnosis. In the patients with aspecific findings, US, as an easy immediate examination, and CT, as a panoramic means, can demonstrate deep lymphadenopathies and focal parenchymal lesions which are sometimes suspected to be abscesses or tumors. Moreover, both methods can provide indications and guide to percutaneous needle biopsies. Especially CT findings can distinguish mycobacterial infections from neoplastic lesions on the basis of the involved anatomical sites and of densitometric features. US and CT are useful means to monitor HIV+ subjects, to manage AIDS patients and to follow-up transplant recipients.