Prevalence of Parasitic Infections and Related Morbidity in Pediatric Patients on Regular Hemodialysis

Abstract

ESRD is an immunosuppressive condition that makes patients more prone to infections, including those caused by opportunistic protozoan parasites. Patients undergoing hemodialysis (HD) suffer from humoral and cell-mediated immune defects and have disturbances in acquired immune response to a variety of antigens. ESRD leads to impaired cell-mediated immunity as a result of lymphopenia and dysfunction of cluster of differentiation 4 (CD4+) T cells. Moreover, uremia-associated pro-inflammatory conditions developed in ESRD patients can lead to irreversible premature aging of T-cell compartment that contributes to the cell-mediated defects and susceptibility to infectious agents. On the other hand, HD induces apoptosis of T cells, decreased phagocytic capacity of neutrophils and monocytes along with abnormal production of pro-inflammatory cytokines by monocytes because of their direct contact with artificial membranes in HD machines. In addition, frequent blood transfusions to patients with ESRD can lead to the development of antibodies against human leukocyte antigens, which can form immune complexes that interfere with cellular immune responses. Opportunistic parasitic infections, including those with Cryptosporidium species, Cystoisospora belli, Cyclospora cayetanensis, Blastocystis hominis, Toxoplasma gondii and microsporidia, have been documented to cause serious complications or even death among immunocompromized patients, including those undergoing HD.