X4 Tropic Virus Prediction Is Associated with a Nadir CD4 T-Cell Count below 100 Cells/mm.

OBJECTIVE: The aim of this study was to evaluate tropism prediction performances of three algorithms [geno2pheno false-positive rate 10% (G2P10), position-specific scoring matrix (PSSM) and a combination of the 11/25 and net charge rules] and to investigate the viral and host factors potentially involved in the X4 or R5 prediction in human immunodeficiency virus-1 (HIV-1) patients. METHODS: Viral tropism was determined in 179 HIV-1-infected patients eligible for CCR5 antagonist therapy. HIV-1 RNA or DNA was extracted and amplified for env gp120 sequencing. In parallel, demographic, viral, immunological and clinical determinants were analyzed. RESULTS: According to the G2P10 algorithm, 48 patients harbored X4 or X4R5 virus. The tropism prediction was concordant for 87.7 and 88.2% of samples when comparing G2P10 with PSSM or with a combination of the 11/25 and net charge rules, respectively. X4 prediction was significantly associated with more than 35 amino acids in the V3 domain (p < 0.0001) and loss of an N-linked glycosylation site (p < 0.0001). Of the factors studied, only the nadir CD4 T-cell count was significantly associated with X4 tropism (p = 0.01). CONCLUSION: We determined that the X4 virus detection is closely linked to the nadir CD4 T-cell count below 100 cells/mm(3) that must be taken into account when considering a CCR5 antagonist therapy switch.

Hepatitis E virus in HIV-infected patients.

OBJECTIVES: Many cases of acute autochthonous hepatitic E virus (HEV) hepatitis have been reported in France, mainly from the south. Chronic HEV infection has recently been described in immunosuppressed patients. Although a potential risk of chronicity exists in HIV-infected patients, no survey has been conducted in this population. The aim of this study was to assess the sero-virological prevalence of HEV in French HIV-infected patients. METHODS: Two hundred and forty-five HIV-infected patients followed at two Infectious Diseases Departments (one in the south, one in the north) were included from January to March 2009. Sera were collected from all patients and tested using anti-HEV IgG and IgM kits. HEV RNA was systematically amplified in the ORF2 region with an in-house method. The IgG avidity index of all IgG-positive samples was determined. RESULTS: Three of the 133 southern patients showed both anti-HEV IgG and IgM positivities, along with cytolysis and biological cholestasis; HEV RNA was amplified in two of these cases, whereas a low IgG avidity index was observed in all three samples. Twelve of the 130 remaining southern patients (9%) showed anti-HEV IgG positivity. The serological prevalence in the 112 northern patients was 3%, which was significantly lower than in the southern patients (P=0.04). No case of acute hepatitis was reported in the north, whereas the prevalence of patients with biochemical liver abnormalities was similar in both areas (P=0.22). CONCLUSIONS: In France, HIV-infected patients are at risk of HEV infection with a serological north-to-south gradient. No case of chronic HEV infection was detected in this study.