Highly-active antiretroviral therapy and oral opportunistic microorganisms in HIV-positive individuals of Thailand

AIM

Oral mucosal lesions and opportunistic microorganisms in HIV-positive Thais treated with highly-active antiretroviral therapy (HAART) for more than 5 years were investigated.

METHODS

A total of 221 HIV-infected patients, comprising 148 HIV patients undergoing HAART for more than 5 years, 20 non-HAART HIV patients, 53 vertically-transmitted (VT) HAART HIV patients, and 30 HIV-negative controls, were examined for CD4+ counts, viral load, saliva secretion rate, and oral mucosal lesions. Samples from the tongue, gingival crevices, and mucosal lesions when present were cultured for the amounts of Candida, staphylococci, enterococci, and aerobic Gram-negative bacilli.

RESULTS

HAART (including HIV-VT) maintained oral microbial homeostasis predominated by alpha-hemolytic streptococci similar to the non-HIV controls and with a low prevalence of mucosal lesions. The HAART group had a reduced saliva secretion rate. The frequency and load of opportunistic microorganisms in the HAART group were similar to the non-HAART group, which was significantly higher than the HIV-negative controls. Candida spp. was found significantly more frequently on the tongue in HIV-infected individuals with CD4+ counts <500 cells/mm(3).

CONCLUSION

Although we did not find lower levels of mucosal lesions among HAART compared to non-HAART individuals, HAART therapy could prolong the time before opportunistic oral pathogens overwhelm the commensal members of oral microbiota.

Influence of highly-active antiretroviral therapy on the subgingival biofilm in HIV-infected patients

AIM

Highly-active antiretroviral therapy (HAART) has been associated with alterations in subgingival biofilm and periodontal disease. The purpose of the present study was to investigate the association between different HAART regimens and the prevalence of periodontal pathogens in HIV-infected patients with chronic periodontitis.

METHODS

Subgingival periodontal pathogens were determined by a DNA chip microarray in a case series in 14 HIV-infected patients receiving HAART with different drug combinations: protease inhibitor (PI)-based HAART versus non-nucleoside reverse transcriptase inhibitor (NNRTI)-based HAART. A statistical analysis was conducted to determine whether specific HAART regimens were associated with 10 periodontal pathogens using odds ratios (OR).

RESULTS

At baseline and after treatment, the patients did not show significant clinical and immunological differences. In general, the highest OR for the prevalence of periodontal pathogens were found in the PI HAART group for Actinomyces viscosus (A. viscosus) (OR: 303), Campylobacter rectus (OR: 90), and Treponema denticola (OR: 25). In the NNRTI HAART group, higher OR were documented for Fusobacterium nucleatum (OR: 56) and Eikenella corrodens (OR: 25). The association between A. viscosus and PI HAART was statistically significant (P = 0.03).

CONCLUSIONS

The results demonstrated statistical associations between subgingival bacteria and antiretroviral drug therapies. Further investigation on the clinical significance and underlying mechanisms are needed to support these findings.

Factors associated with the immune response to hepatitis A vaccination in HIV-infected patients in the era of highly active antiretroviral therapy

INTRODUCTION

HIV seropositivity is considered a risk factor for complications in hepatitis A virus (HAV) infection. HAV vaccination schedules are widely implemented in HIV-infected patients, but the immune response remains impaired.

METHODS

We analysed the response to vaccination (antiHAV titres ≥20IU/l) in 282 HIV-infected patients included in a standard (1440 Elisa Units (EU) at 0, 6 months) or rapidly accelerated schedule (720 EU at 0, 7, 21 days and 6 months) between 1997 and 2009. Factors associated with the response to vaccination were analysed using logistic regression.

RESULTS

The overall response rate was 73.4%. Male sex (OR: 0.16, 95% CI 0.05-0.51) and hepatitis C virus co-infection (OR: 0.30, 95% CI 0.14-0.74) were associated with a lower probability of response. Protective antibody response was associated with a higher CD4/CD8 ratio (OR: 3.69, 95% CI 1.3-10.5) and having received two doses of standard schedule (compared with patients receiving only one dose of the same schedule) (OR: 2.51, 95% CI 1.22-5.15). Three doses of the rapidly accelerated schedule were not more effective than a single dose of 1440 EU (OR: 1.32, 95% CI 0.48-3.63).

CONCLUSION

The low responses observed in patients receiving a single dose suggest the need to emphasize adhesion to vaccination protocols to avoid failure. The CD4/CD8 ratio may be considered as an immune status marker which could help to better choose the moment of vaccination. Our findings underscore the importance of identifying strategies that optimize the timing and effectiveness of hepatitis A vaccination in HIV-infected patients and of the need for further studies on individual factors such as sex and hepatitis C co-infection that may affect the response to vaccination. Likewise, the sub-optimal effectiveness of three doses of 720 EU in the rapidly accelerated schedule, if confirmed in future studies, might lead to a revision of the current schedule recommended for HIV-infected travellers.