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Human immunodeficiency virus (HIV) infection facilitates the development of other infections and lesions including oral papilloma, which has been associated with human papillomavirus (HPV). In analyzing the presence of HPV 16 and 18 by in situ hybridization in oral papillomas from five HIV+ male dental patients, HPV 16 and 18 were observed in 9 of 16 (52.2%) histopathologic specimens. All positive lesions occurred in heterosexual males admitting to oral sexual contact with a female partner (Pearson's correlation; p = 0.0088). These results suggest that oral sexual behavior may be a contributing factor in the presence of HPV 16 and 18 in oral papilloma.

Objective: Interest in Candida dubliniensis has led to renewed clinical investigations regarding incidence, drug resistance, pathogenesis, and epidemiology of fungal infections in patients with HIV. C dubliniensis phenotypically resembles Candida albicans in many respects, yet it can be identified and differentiated as a unique Candida species by its phenotypic and genetic profiles. The purpose of this study was to prospectively evaluate the prevalence of C dubliniensis in clinical isolates and determine the clinical and demographic characteristics of patients harboring C dubliniensis., Study Design: Over a 6-week period, 24 yeast-positive isolates from HIV-positive dental patients were screened for C dubliniensis through use of phenotypic criteria. HIV viral load, CD4 count, and complete oral health evaluations were performed on each patient at the same visit during which the oral fungal surveillance culture was taken., Results: Six isolates from 24 HIV-seropositive and yeast-positive patients were shown to be consistent phenotypically and by electrophoretic karyotyping with the European reference strain of C dubliniensis. Dose-dependent susceptibility to fluconazole was shown in one of the C dubliniensis isolates. Five of the 6 patients demonstrated moderate to high viral loads. General oral health, as evidenced by the presence of advanced periodontal lesions and a high decayed, missing, and filled teeth index (>20), was poor in 3 of the 6 patients with C dubliniensis and 7 of the 18 patients with C albicans. A history of intravenous drug abuse was present in 50% of the C dubliniensis -positive patients, which is representative of the HIV-positive population at the hospital., Conclusions: In this small sample, C dubliniensis represented 25% of the yeast-positive cultures. The clinical significance of this interesting species in the United States may be related to high viral load, rapid AIDS progression, and/or concomitant oral disease, such as a high caries index or periodontal disease.

This study showed that impoverished Nigerian children at risk for cancrum oris (noma) had significantly reduced plasma concentrations of zinc (< 10.8 micromol/L), retinol (< 1.05 micromol/L), ascorbate (< 11 micromol/L), and the essential amino acids, with prominently increased plasma and saliva levels of free cortisol, compared with their healthy counterparts. The nutrient deficiencies, in concert with previously reported widespread viral infections (measles, herpesviruses) in the children, would impair oral mucosal immunity. We postulate, subject to additional studies, that evolution of the oral mucosal ulcers including acute necrotizing gingivitis to noma is triggered by a consortium of microorganisms of which Fusobacterium necrophorum is a key component. Fusobacterium necrophorum elaborates several dermonecrotic toxic metabolites and is acquired by the impoverished children via fecal contamination resulting from shared residential facilities with animals and very poor environmental sanitation.

Free cortisol concentrations in unstimulated whole saliva samples, collected at 10.00 to 11.00 h, from 23 unmedicated HIV-positive patients and 14 control subjects were measured by radioimmunoassay. Mean cortisol level (nmol/l +/- SD) was significantly higher in the HIV patients than in control subjects (27.4 +/0 9.3 vs. 10.1 +/- 3.5). Two HIV patients with pseudomembranous candidiasis had the highest saliva cortisol concentrations (mean of 48.5 nmol/l). Two other HIV patients (one with Kaposi's sarcoma and the other with periodontitis) had a mean cortisol value of 29.9 nmol/l. The possibility of plasma contamination of whole saliva in the HIV patients with inflammatory oral mucosal lesions notwithstanding, our findings suggest an increased oral burden of cortisol in both the asymptomatic and symptomatic HIV-infected individuals. Glucocorticoids caused immunosuppression, provide selective growth advantage to various microorganisms including the fungi, and enhance replication or reactivation of latent viruses (e.g. EBV, CMV, Kaposi's sarcoma-associated herpes viruses). Our findings suggest a need to evaluate the relevance of endogenous glucocorticoid excess in blood and saliva to the causation of some major AIDS-associated oral lesions such as candidiasis, Kaposi's sarcoma, oral hairy leukoplakia and necrotizing gingivitis.

Tobacco (smoking and smokeless) use and excessive consumption of alcohol are considered the main risk factors for oral cancer (ICD9 140-149). Conspicuous national and international variations in oral cancer incidence and mortality rates, as well as observations in migrant populations, raise the possibility that diet and nutritional status could be an important etiologic factor in oral carcinogenesis. As shown in this report, abuse of alcohol and tobacco has serious nutritional implications for the host, and generates increased production of reactive free radicals as well as eliciting immunosuppression. Maintenance of optimal competence of the immune system is critical for cancer surveillance. Active oxygen species and other reactive free radicals mediate phenotypic and genotypic alterations that lead from mutation to neoplasia. Consequently, the most widely used chemopreventive agents against oral cancer (e.g., vitamins A, E, C, and beta-carotene) are anti-oxidants/free radical scavengers. These anti-oxidants, both natural and synthetic, neutralize metabolic products (including reactive oxygen species), interfere with activation of procarcinogens, prevent binding of carcinogens to DNA, inhibit chromosome aberrations, restrain replication of the transformed cell, suppress actions of cancer promoters, and may even induce regression of precancerous oral lesions such as leukoplakia and erythroplakia. Malnutrition is characterized by marked tissue depletion of anti-oxidant nutrients, including GSH (gamma-glutamyl-cysteinyl-glycine), a key cellular anti-oxidant as well as a modulator of T-cell activation. GSH or its precursor cysteine inhibits activation of the nuclear transcription factor kB(NFkB), and has been shown to be protective against chemically induced oral cancer and leukoplakia. Alcohol-, tobacco-, and/or malnutrition-induced immunosuppression promotes impaired salivary gland function and oral mucosal immunity, a prominent reduction in the number of helper CD4 cells with less marked changes in number of suppressor T-cells, and depressed NK cell activity, among others. These suggest a breakdown in capacity or the malnourished to mount effective tumor surveillance. This review article underscores the compounding but important roles of nutritional/dietary factors in the long-established causal link between abuse of alcohol and tobacco (smoking and smokeless) and oral cancer.