C-reactive protein (Crp) and interleukin 6 (IL6) in HIV-related conditions.

Background: Crp is an acute phase protein induced by Il6 via hepatic synthesis. Accordingly, it is expected to augment in all settings in which Il6 is increased, e.g. HIV-related opportunistic infections (OI) and malignancies (M), first of all Kaposi's sarcoma (KS). Our aim was to assess the behaviour of Crp vs. IL6 in HIV-related conditions. Methods: Crp, IL6, CD4 cell counts and ferritin were measured (a single assessment) in 2 groups of HIV patients (pts): GROUP A - 12 pts with KS: 6 with progressed disease (PD) undergoing chemotherapy and 6 with stable disease(SD), untreated. GROUP B - 18 pts with end-stage AIDS, 9 with M (KS, 5, HD, 1, NHL, 2, undefined pancreatic malignancy, 1), 9 with OI (CNS toxoplasmosis, 2, disseminated CMV infection, 4, AIDS dementia complex, 2 demyelinating encephalopathy, 1). Results: Mean values are reported in table 1Conclusions: In our study, while IL6 was predictably increased in advanced vs. stable KS and reached higher values in neoplastic vs infectious complications, like ferritin, Crp remained within normal limits in spite of progression of both KS and immune deficiency. It rised to slightly elevated values only in severely ill pts with neoplasm. This surprising lack of correlation (confirmed by further dilution of samples), was not due to hepatic failure and remains unexplained.