Can we relay on HIV Ab and HCV Ab result , to diagnose HIV and HCV while we know ESRD patients are immune compromised?
This is very excellent point!
For example, the most recent review article from Nature review: http://www.nature.com/nrneph/journal/vaop/ncurrent/pdf/nrneph.2015.5.pdf
demonstrating that:
"In ESRD, Clinics with a high prevalence of HCV infection are estimated to have an 18% false-negative anti-HCV test rate."
It depends on grade of immune deficiency; if you have any doubt better to search HCV -RNA than HCV-Ab. For HIV we have the most recent test with contemporary search of Ag P24 and HIV-Ab, so not useful to screen for HIV-RNA . I have heard that a similiar test (Ag-Ab) for HCV will be available soon.
Good question,
my opinion is that in hemodyalisis patients we could have an underestimation of HCV and HIV patients because of the immunodeficiency: PCR should always be done in the case of suspicion
It works in both sites. It is a minority, but still you should remember about false positive results of anti-HCV. Some studies report even 15% of false positive results in hemodialysis patients. The problem might be important in samples from patients with SLE, RA, portal cirrhosis, when there is high concentration of immunoglobulin components. In a situation with high IgG concentration (f ex. some mentioned auto-antibody mediated diseases) there is a tendency for immunoglobulins to be bound to the micro-well surface by direct adsorption or by indirect capture via the surface molecules, and this gives false positive result. Mentioned diseases as probable causes of CKD might be an issue in HD population. Thus this is another reason to perform a confirmation test, I mean PCR.
Sorry for late answering. May be the below paper can help you for the prevalence of HCV in immunocompromised patients. Wafaa M. El-Emshaty, Douaa Raafat, Doaa M. Elghannam, Niveen Saudy, Ehab E. Eltoraby, Abd Elhameed A. Metwalli. DIAGNOSTIC PERFORMANCE OF AN IMMUNOASSAY FOR SIMULTANEOUS DETECTION OF HCV CORE ANTIGEN AND ANTIBODIES AMONG HAEMODIALYSIS PATIENTS. Brazilian Journal of Microbiology (2011) 42: 303-309
For HIV you must use PCR.
Best regard.
Nouhoum Bouaré
PH PhD, CNAM Bamako