Factors associated with long-term CD4 cell recovery in HIV-infected patients on successful antiretroviral therapy.

OBJECTIVES: The aim of the study was to study the factors associated with immunological recovery in HIV-infected patients with suppressed viral load. METHODS: Nadir and current CD4 cell counts were recorded in 821 patients, as well as many demographic, epidemiological, lifestyle, clinical, therapeutic, genetic, laboratory, liver fibrosis and viral hepatitis parameters. RESULTS: The median age of the patients was 44.4 years [interquartile range (IQR) 40.3-48.0 years], the median time since HIV diagnosis was 15.3 years (IQR 10.5-18.9 years), the median time of suppressed viral load was 7.0 years (IQR 4.0-10.0 years) and the median time on the current antiretroviral regimen was 2.8 years (IQR 1.4-4.7 years). The median nadir and current CD4 counts were 193.0 (IQR 84.0-301.0) and 522.0 (IQR 361.0-760) cells/µL, respectively, separated by a median period of 10.2 years (IQR 5.9-12.9 years). The median CD4 count gain during follow-up was 317.0 (IQR 173.0-508.0) cells/µL. Many variables were associated with CD4 cell gains in univariate analyses, including age, gender, epidemiology, prior clinical conditions, fibrosis stage, transient elastometry, aspartate aminotransferase (AST), nadir CD4 count and hepatitis B and C virus infections and genotypes, as well as the durations of follow-up since nadir CD4 count, overall antiretroviral treatment, current antiretroviral regimen, protease inhibitor therapy and suppression of viral load. Multivariate analysis revealed that longer duration of HIV suppression (P < 0.0001), more advanced clinical Centers for Disease Control and Prevention (CDC) stages (P < 0.0001), younger age (P = 0.0003), hepatitis C virus genotypes 1 and 4 (P = 0.003), sexual acquisition of HIV (P = 0.004), and lower transient elastometry values (P = 0.03) were independent predictors of CD4 cell gains. Overall, the model accounted for 14.2% of the variability in CD4 count. CONCLUSIONS: In addition to the duration of HIV suppression, HIV-related diseases, HIV epidemiology, age, hepatitis C virus genotypes, and liver fibrosis were independently associated with long-term immunological recovery.

The effect of gender and genetic polymorphisms on matrix metalloprotease (MMP) and tissue inhibitor (TIMP) plasma levels in different infectious and non-infectious conditions.

Matrix metalloproteases (MMPs) are increased in different infections due to their role in controlling immune responses and are regulated by tissue inhibitors (TIMPs). Different MMP promoter single nucleotide polymorphisms (SNPs) induce changes in MMP genes, mRNA and protein expression. Gender might also modify MMP plasma levels. In order to determine the weight of these variables on MMP secretion we studied MMP-1, -2, -3, -8, -9, -10, -13 and TIMP-1, -2, -4 plasma levels in 90 patients with severe bacterial sepsis, 102 with anti-retroviral (ARV)-treated HIV monoinfection, 111 with ARV-treated HIV-hepatitis C virus (HCV) co-infection and 86 non-infected controls (45 stroke and 41 trauma patients). MMP-1(-1607 1G/2G), MMP-3(-1612 5A/6A), MMP-8(-799C/T), MMP-9(-1562 C/T) and MMP-13(-77A/G) SNPs were genotyped. MMP-3 plasma levels were significantly higher in men than in women in each diagnostic group, and MMP-3 SNP allele 6A carriers also had higher levels than allele 5A carriers, an effect that was magnified by sepsis. Independent predictors of higher MMP-3 levels were male gender (P = 0.0001), MMP-3(-1612 5A/6A) SNP (P = 0.001), higher levels of TIMP-4 (P = 0.004) and MMP-8 (P = 0.006) and lower levels of MMP-1 (P = 0.03) by multivariate analysis. No strong associations with gender or SNPs were observed for other MMPs or TIMPs. In conclusion, male gender and MMP-3(-1612 5A/6A) 6A allele carriage increased MMP-3 plasma levels significantly, especially in patients with severe bacterial sepsis. This confounding gender effect needs to be addressed when evaluating MMP-3 plasma levels in any infectious or non-infectious condition.

Didanosine (ddI) associates with increased liver fibrosis in adult HIV-HCV coinfected patients.

The role of exposure to antiretrovirals (ARV) and serum matrix metalloproteases (MMPs) on liver fibrosis (LF) progression in human immunodeficiency virus (HIV) mono or HIV- hepatitis C virus (HCV) coinfection is unclear. Thus, 213 Caucasian adult HIV-infected patients were studied, 111 of whom had HCV-coinfection and 68 were HCV-monoinfected. Patients with ethanol consumption >50 g/day, hepatitis B coinfection, non-infective liver diseases or HAART adherence <75% were excluded. LF was assessed by transient elastometry (TE, Fibroscan). Serum levels of MMPs (MMP -1,-2,-3,-8,-9,-10 and -13) and their tissue inhibitors (TIMP-1,-2 and -4) were measured by ELISA microarrays. Associations with LF were statistically analysed. Protease inhibitors, usually administered to patients with advanced LF were excluded from the analysis. Increased LF was significantly associated with d4T (P = 0.006) and didanosine (ddI) use (P = 0.007), months on d4T (P = 0.001) and on ARV (P = 0.025), duration of HIV (P < 0.0001) and HCV infections (P < 0.0001), higher HIV (P = 0.03) and HCV loads (P < 0.0001), presence of lipodystrophy (P = 0.02), male gender (P = 0.02), older age (P = 0.04), low nadir (P = 0.02) and current CD4(+) T-cells (P < 0.0001), low gain of CD4(+) T-cells after HAART (P = 0.01) and higher MMP-2 (P = 0.02) and TIMP-2 serum levels (P = 0.02). By logistic regression the only variables significantly associated with increased LF were: use of ddI (OR 8.77, 95% CI: 2.36-32.26; P = 0.005), male gender (OR 7.75, 95% CI: 2.33-25.64, P = 0.0008), HCV viral load (in log) (OR 3.53, 95% CI: 2.16-5.77; P < 0.0001) and age (in years) (OR 1.21, 95% CI: 1.09-1.34, P = 0.0003). We conclude that only higher HCV viral load, older age, male gender, and use of ddI associated independently with increased LF in our study.

Meropenem monotherapy is as effective as and safer than imipenem to treat brain abscesses.

The efficacy of carbapenems versus cefotaxime (8g/day)+metronidazole (1.5-2g/day) [combined standard chemotherapy (CSC)] for the treatment of brain abscess was compared. Fifty-nine adult patients with brain abscesses received either imipenem or meropenem (3-4g/day) or CSC for a mean of 5 weeks, in addition to neurosurgery in most cases. Cure was obtained in 84.7% of cases; 42/47 (89.4%) on carbapenems [18/22 (81.8%) on imipenem versus 24/25 (96.0%) on meropenem] and 8/12 (66.7%) on CSC (P=0.06). Seven patients with multiple abscesses were treated with imipenem (1 died; cure rate 85.7%), five with meropenem (all survived; cure rate 100%) and five with CSC (2 died; cure rate 60%) (P<0.4). Neurosurgery was performed in 43/59 cases (72.9%); 17 (77.3%) in the imipenem group, 21 (84.0%) in the meropenem group and 5 (41.7%) in the CSC group (P=0.02). There was no significant difference in the rate of relapse requiring re-intervention. Treatment with meropenem was associated with a lower mortality than CSC (P=0.026). Seizures were observed only with carbapenems [8/22 (36.4%) for imipenem versus 2/25 (8.0%) for meropenem; P=0.03]. Carbapenems were more effective than CSC for treatment of brain abscesses. Because meropenem induced significantly fewer seizures than imipenem with at least the same clinical efficacy, the former appears to be a better choice to treat this infection.