Endocrine Abstracts

Introduction: Vitamin D insufficiency (D-INSUFF) has been associated with impaired immune response in human inmunodeficiency virus (HIV) patients and a worse prognosis in patients with liver fibrosis. Nevertheless, few studies have explored the influence of D-INSUFF in immunological response and liver parameters in HIV and hepatitis C virus co-infected patients (HIV/HCV) on long term highly active antiretroviral therapy (HAART) with successful immune and virological response. In this cross-sectional study, first we determined the prevalence of D-INSUFF in a cohort of HIV/HCV outpatients with liver fibrosis and second, we assessed whether the existence of D-INSUFF involves the appearance of relevant immunological data and/or particular clinical aspects related to liver disease.

Methods/design: Thirty-six consecutive HIV/HCV co-infected men (mean age: 48±5.1 years) with liver fibrosis on long term HAART were included in this study. D-INSUFF was defined as 25OH-D levels ≤30 ng/ml. Liver fibrosis was defined as the presence of a liver stiffness ≥9 kPa measured by FibroScan. Age, data related to HIV and HCV infection, anthropometric, nutritional and metabolic parameters were recorded. Child-Pugh and Model for End-Stage Liver Disease (MELD) were used for assessing the severity of chronic liver disease.

Results: The mean serum 25(OH)-D concentration was 29.1±11.5 ng/ml, with a prevalence of D-INSUFF of 61.1% (mean level: 21.7±4.3 ng/ml). D-INSUFF patients as compared to patients who had normal levels of 25OH-D significantly had lower CD4 lymphocyte count (462.2±170.5/mm³ vs 745.9±107.3/mm³; P=0.02) and lower serum albumin levels (4.4±0.2 vs 4.8±0.3 g/dl; P=0.05). Serum PTHi, calcium and phosphorus levels, liver stiffness value, Child-Pugh and MELD scores were not significantly different among D-INSUFF patients or those with normal 25OH-D level.

Conclusions: Although the level of CD4 lymphocytes is adequate in both groups, the immunological response to HAART is less effective in HIV/HVC co-infected patients with vitamin D insufficiency. Strategies to supplement vitamin D in these patients may help to improve immune status.