Treatment of oral candidiasis in HIV infection

HIV Infection and Oral Manifestations: An Update

Human immunodeficiency virus (HIV) causes a complete depletion of the immune system; it has been a major health issue around the world since the 1980s, and due to the reduction of CD4+ T lymphocytes levels, it can trigger various opportunistic infections. Oral lesions are usually accurate indicators of immunosuppression because these oral manifestations may occur as a result of the compromised immune system caused by HIV infection; therefore, oral lesions might be initial and common clinical features in people living with HIV. So, it is necessary to evaluate and understand the mechanism, prevalence, and risk factors of oral lesions to avoid the increase morbidity among those with oral diseases.

Oral Fungal Infections: Diagnosis and Management

Oral and maxillofacial fungal infections can appear in high-risk patients, including those immunocompromised. This article explores common oral manifestations of fungal infections in the oral cavity as primary lesions or as a result of disseminated disease. By far the most common oral fungal infection experienced in dentistry is oral candidiasis, which is reviewed in depth from simple oral infections to invasive candidiasis. The review aids the dental practitioner in understanding the full scope of Candida infections and other fungal infections. In addition to candidiasis, various other fungal infections are reviewed, including mucormycosis, aspergillosis, blastomycosis, histoplasmosis, cryptococcosis, and coccidioidomycosis.

Oral mycoses and other opportunistic infections in HIV: therapy and emerging problems - a workshop report

Oral mycoses and other opportunistic infections are recognized features of HIV infection even after four decades of the epidemic. The therapeutic options, challenges of therapy, and evolving patterns of opportunistic infections were evaluated by the workshop. It was observed that high Candida counts and infection are still more prevalent in HIV-positive individuals even in the era of antiretroviral therapy. Furthermore, one or more non-Candida albicans are present in some HIV-positive individuals. While Candida species are more virulent in HIV infection, similar virulence may be present in other states of immunosuppression. Consequently, the interplay between host factors and virulence ultimately determines the clinical outcomes. Adverse clinical outcomes such as candidemia and other deep fungal infections are on the increase in HIV infection. Disseminated histoplasmosis and penicilliosis have been reported, especially with low CD4 counts. Even with advances in antifungal therapy, mortality and morbidity from deep fungal infections have not changed significantly. In addition, long-term exposure to common antifungal drugs such as fluconazole has led to the development of antifungal resistance in 6% to 36%. Development of new antifungal therapeutic agents and the use of alternative therapies may offer breakthrough. In addition, effective strategies to enhance the host immune status are being explored.

Topical gentian violet compared with nystatin oral suspension for the treatment of oropharyngeal candidiasis in HIV-1-infected participants

OBJECTIVE

Compare the safety and efficacy of topical gentian violet with that of nystatin oral suspension (NYS) for the treatment of oropharyngeal candidiasis in HIV-1-infected adults in resource-limited settings.

DESIGN

Multicenter, open-label, evaluator-blinded, randomized clinical trial at eight international sites, within the AIDS Clinical Trials Group.

STUDY PARTICIPANTS AND INTERVENTION

Adult HIV-infected participants with oropharyngeal candidiasis, stratified by CD4 cell counts and antiretroviral therapy status at study entry, were randomized to receive either gentian violet (0.00165%, BID) or NYS (500 000 units, QID) for 14 days.

MAIN OUTCOME MEASURE(S)

Cure or improvement after 14 days of treatment. Signs and symptoms of oropharyngeal candidiasis were evaluated in an evaluator-blinded manner.

RESULTS

The study was closed early per Data Safety Monitoring Board after enrolling 221 participants (target = 494). Among the 182 participants eligible for efficacy analysis, 63 (68.5%) in the gentian violet arm had cure or improvement of oropharyngeal candidiasis versus 61 (67.8%) in the NYS arm, resulting in a nonsizable difference of 0.007 (95% confidence interval: -0.129, 0.143). There was no sizable difference in cure rates between the two arms (-0.0007; 95% confidence interval: -0.146, 0.131). No gentian violet-related adverse events were noted. No sizable differences were identified in tolerance, adherence, quality of life, or acceptability of study drugs. In gentian violet arm, 61 and 39% of participants reported 'no' and 'mild-to-moderate' staining, respectively. Cost for medication procurement was significantly lower for gentian violet versus NYS (median $2.51 and 19.42, respectively, P = 0.01).

CONCLUSION

Efficacy of gentian violet was not statistically different than NYS, was well tolerated, and its procurement cost was substantially less than NYS.

HIV infection and microbial diversity in saliva

Limited information is available about the effects of HIV and subsequent antiretroviral treatment on host-microbe interactions. This study aimed to determine the salivary microbial composition for 10 HIV-seropositive subjects, before and 6 months after highly active antiretroviral therapy (HAART), compared with that for 10 HIV-seronegative subjects. A conventional culture and two culture-independent analyses were used and consistently demonstrated differences in microbial composition among the three sets of samples. HIV-positive subjects had higher levels of total cultivable microbes, including oral streptococci, lactobacilli, Streptococcus mutans, and Candida, in saliva than did HIV-negative subjects. The total cultivable microbial levels were significantly correlated with CD4+ T cell counts. Denaturing gradient gel electrophoresis (DGGE), which compared the overall microbial profiles, showed distinct fingerprinting profiles for each group. The human oral microbe identification microarray (HOMIM) assay, which compared the 16S rRNA genes, showed clear separation among the three sample groups. Veillonella, Synergistetes, and Streptococcus were present in all 30 saliva samples. Only minor changes or no changes in the prevalence of Neisseria, Haemophilus, Gemella, Leptotrichia, Solobacterium, Parvimonas, and Rothia were observed. Seven genera, Capnocytophaga, Slackia, Porphyromonas, Kingella, Peptostreptococcaceae, Lactobacillus, and Atopobium, were detected only in HIV-negative samples. The prevalences of Fusobacterium, Campylobacter, Prevotella, Capnocytophaga, Selenomonas, Actinomyces, Granulicatella, and Atopobium were increased after HAART. In contrast, the prevalence of Aggregatibacter was significantly decreased after HAART. The findings of this study suggest that HIV infection and HAART can have significant effects on salivary microbial colonization and composition.

A study of antifungal drug sensitivity of Candida isolated from human immunodeficiency virus infected patients in Chennai, South India

Background:

The purpose of this study was to study the drug sensitivity pattern of Candida seen in HIV seropositive patients in Chennai, South India.

Materials and Methods:

36 oral rinse samples were collected from HIV seropositive individuals with (21 patients) and without (15 patients) clinical candidiasis. The type of Candidiasis, quantitative estimation, differentiation of candida species and antifungal susceptibility testing was done using different tests.

Results:

In the 21 patients with candidiasis, pseudomembranous type predominated with low CD4 counts and high colony forming units. Antifungal Drug sensitivity test revealed resistance to fluconazole which is attributed to long term exposure to the drug.

Conclusion:

The results of the study confirm the hypothesis that candidal species can be isolated in HIV positive patients with clinical candidiasis. In HIV infection there are fluconazole resistant candida species emerging mainly due to long term exposure to the drug.

Candida and candidiasis in HIV-infected patients: where commensalism, opportunistic behavior and frank pathogenicity lose their borders

In this era of efficacious antiretroviral therapy and consequent immune reconstitution, oropharyngeal and esophageal candidiasis (OPC and OEC) still remain two clinically relevant presentations in the global HIV setting. Both diseases are predominantly caused by Candida albicans, a polymorphic fungus which is a commensal microbe in the healthy individual but can become an aggressive pathogen in a debilitated host. Actually, C. albicans commensalism is not the result of a benign behavior of one of the many components of human microbiota, but rather the result of host's potent innate and adaptive immune responses that restrict the growth of a potentially dangerous microrganism on the epithelia. An important asset guarding against the fungus is the Th17 functional subset of T helper cells. The selective loss of these cells with the progression of HIV infection causes the decay of fungal containment on the oral epithelium and allows C. albicans to express its pathogenic potential. An important part of this potential is represented by mechanisms to evade host immunity and enhance inflammation and immunoactivation. In C. albicans, these mechanisms are mostly incorporated into and expressed by characteristic morphogenic transitions such as the yeast-to-hyphal growth and the white-to-opaque switch. In addition, HIV infection generates an 'environment' selecting for overexpression of the virulence potential by the fungus, particularly concerning the secreted aspartyl proteinases (Saps). These enzymes can degrade critical host defense components such as complement and epithelial defensive proteins such as histatin-5 and E-cadherin. It appears that part of this enhanced Candida virulence could be induced by the binding of the fungus to HIV and/or induced by HIV proteins such as GP160 and tat. Both OPC and OEC can be controlled by old and new antimycotics, but in the absence of host collaboration, anticandidal therapy may become ineffective in the long run. For these reasons, new therapeutics targeting virulence factors and specific immune interventions are being addressed. Among these new approaches, vaccination is a promising one. Two subunit vaccines based on antigens dominantly expressed by C. albicans in vivo, that is the Als3 adhesin and Sap2, have recently undergone phase 1 clinical trials. Overall, studies of Candida and candidiasis in the HIV-positive patient while certainly contributing to a more effective control of the microorganism may also provide useful information on HIV-host relationship itself that can assist the fight against the virus.

Susceptibilities of Candida albicans mouth isolates to antifungal agents, essentials oils and mouth rinses

Forty Candida albicans strains isolated from patient's mouth with fixed orthodontic appliances were analyzed to their susceptibilities to antifungal agents, mouth rinses and essential oils. Susceptibility to fluconazole, econazole, miconazole and ketoconazole, amphotericin B and nystatin was assessed by the disk diffusion (DD) method based on the Clinical and Laboratory Standards Institute M44-A protocol, and by Etest (fluconazole and amphotericin B). The susceptibilities to mouth rinses and essential oils were also determined by the DD technique. All isolates tested were susceptible (S) to amphotericin B, nystatin and fluconazole. The overall concordance between the DD and the Etest was 100% for amphotericin and fluconazole. One isolate was resistant to econazole (2.5%) and the other to ketoconazole (2.5%). Econazole and ketoconazole had the highest percentages of susceptible dose dependent (SDD), 55 and 95%, respectively. Regarding to the susceptibility isolates profile, seven phenotypes were detected, and the 3 more represented (90% of the isolates) of them were SDD to one, two or three azoles. The study of mouth rinses showed a high variability of efficacy against C. albicans. The results showed that the isolates susceptibility to essential oils differed (P < 0.05). The profile activity was: cinnamon > laurel > mint > eucalyptus > rosemary > lemon > myrrh > tangerine. The main finding was that the susceptibility to cinnamon and laurel varied among the three more representative antifungal phenotypes (P < 0.05). The susceptibility of econazole-SDD isolates to cinnamon and lemon was higher than those of the econazole-S yeasts (P < 0.05). In contrast, econazole-SDD isolates were less affected by laurel than econazole-S counterparts (P < 0.05).

HIV aspartyl protease inhibitors as promising compounds against Candida albicans André Luis Souza dos Santos

Cells of Candida albicans (C. albicans) can invade humans and may lead to mucosal and skin infections or to deep-seated mycoses of almost all inner organs, especially in immunocompromised patients. In this context, both the host immune status and the ability of C. albicans to modulate the expression of its virulence factors are relevant aspects that drive the candidal susceptibility or resistance; in this last case, culminating in the establishment of successful infection known as candidiasis. C. albicans possesses a potent armamentarium consisting of several virulence molecules that help the fungal cells to escape of the host immune responses. There is no doubt that the secretion of aspartyl-type proteases, designated as Saps, are one of the major virulence attributes produced by C. albicans cells, since these hydrolytic enzymes participate in a wide range of fungal physiological processes as well as in different facets of the fungal-host interactions. For these reasons, Saps clearly hold promise as new potential drug targets. Corroborating this hypothesis, the introduction of new anti-human immunodeficiency virus drugs of the aspartyl protease inhibitor-type (HIV PIs) have emerged as new agents for the inhibition of Saps. The introduction of HIV PIs has revolutionized the treatment of HIV disease, reducing opportunistic infections, especially candidiasis. The attenuation of candidal infections in HIV-infected individuals might not solely have resulted from improved immunological status, but also as a result of direct inhibition of C. albicans Saps. In this article, we review updates on the beneficial effects of HIV PIs against the human fungal pathogen C. albicans, focusing on the effects of these compounds on Sap activity, growth behavior, morphological architecture, cellular differentiation, fungal adhesion to animal cells and abiotic materials, modulation of virulence factors, experimental candidiasis infection, and their synergistic actions with classical antifungal agents.

Antifungal effect of mouth rinses on oral Candida counts and salivary flow in treatment-naïve HIV-infected patients

Oral candidiasis is a major problem in developing countries where antiretroviral therapy is available to a small percentage of the infected population. HIV patients are prone to xerostomia and predisposed to Candida infection. Preventing oral candidiasis is better than the frequent use of antifungals that may lead to the development of drug resistance. This study investigated the ability of commercial mouth rinses and sodium bicarbonate to reduce salivary Candida and to improve the saliva flow of HIV-positive patients. One hundred fifty HIV patients without oral candidiasis were examined for oral lesions initially and after 2, 4, and 12 weeks. Unstimulated saliva was collected; the volume was measured and cultured for yeasts. Subjects were provided with mouth rinses containing either benzydamine hydrochloride, benzydamine hydrochloride with chlorhexidine gluconate, triclosan with sodium fluoride, 5% sodium bicarbonate, or placebo and asked to rinse twice daily for 12 weeks. The effect of the mouth rinses and placebo on Candida counts and saliva flow was analyzed using analysis of variance (ANOVA). A total of 108 patients completed the trial, 35 missed appointments, 4 died, 2 developed oral candidiasis, and 1 herpetic lesion. Triclosan/fluoride decreased the Candida count more than the placebo (p = 0.005) while chlorhexidine/benzydamine hydrochloride (p = 0.001) and triclosan/fluoride mouthrinses (p = 0.002) increased the salivary flow during the initial 4 weeks. The most effective mouth rinse triclosan/fluoride decreased oral Candida counts and increased saliva flow. Studies are needed to determine the efficacy of these mouth rinses for the long-term prevention of clinical oral candidiasis in adult HIV-positive patients.

Effect of antifungal treatment on the prevalence of yeasts in HIV-infected subjects

Oral candidiasis, the most common opportunistic infection in patients with HIV infection, is usually associated with Candida albicans. Several factors may influence the carriage of Candida, including immunocompromised conditions and HIV infection, colonization by yeasts from different geographical areas and antimycotic treatment. This study investigated the Candida carrier rate, level and types of yeast in HIV-positive and -negative subjects, and the effect of previous exposure to antifungal drugs on the level of yeasts in HIV-positive patients in Gauteng, South Africa. Unstimulated saliva was collected from 332 HIV-positive patients and 100 HIV-negative subjects and cultured for yeasts. The number and species of yeast were determined. HIV-positive patients who carried yeasts were divided into two groups depending upon their previous antifungal drug exposure, and the level of Candida carriage in each group was compared. The Candida carrier rate in the HIV-positive patients (81.3%) was slightly higher than previously reported and significantly higher (P<0.001) than in the HIV-negative group (63%). The carrier rate in the HIV-negative group was also higher than in earlier studies. Fourteen per cent of the HIV-positive patients carried more than 10,000 c.f.u. ml-1 whereas none of the HIV-negative subjects carried this large a number of yeasts (P<0.001). Seventy per cent of the yeasts were identified as C. albicans and approximately 30% as non-albicans species. In conclusion, the Candida carrier rate is higher in the South African population than elsewhere. HIV-positive patients carry more and a greater variety of yeasts than HIV-negative subjects. Exposure to antifungal drugs has no effect on the level of yeast carriage in HIV-positive patients.

Antifungal activity of DNA-lipid complexes and DNA-lipid films againstCandida species

In this study amphiphilic lipids, DNA-lipid complexes, and DNA-lipid films were prepared, and their antifungal activity against Candida species was examined. The amphiphilic lipids were synthesized from a reaction of glycine or L-alanine with n-alkyl alcohol in the presence of p-toluene sulfonic acid. DNA-lipid complexes, which were prepared by the simple mixing of DNA and amphiphilic lipids, were insoluble in water. Self-standing, water-insoluble DNA-lipid films were prepared by casting the DNA-lipid complexes from a chloroform/ethanol solution. The antifungal activities of the lipids and DNA-lipid complexes against the Candida species were evaluated by minimum inhibitory concentrations (MICs); those of DNA-lipid films were evaluated by the disk diffusion method. The seven kinds of lipids, DNA-lipid complexes, and DNA-lipid films showed antifungal activity, and no differences were seen in the antifungal activities between glycine and L-alanine derivatives. The lipids, DNA-lipid complexes, and DNA-lipid films, which have shorter alkyl chain length in lipids, showed antifungal activity against all Candida species. However, the effect of antifungal activity against Candida species decreased with increased alkyl chain length in lipids. In this study, it was found that lipids, DNA-lipid complexes, and films with a decyl or dodecyl group exhibit more favorable antifungal activity.

Efficacy of chlorhexidine gluconate rinse for treatment and prevention of oral candidiasis in HIV-infected children: a pilot study

PURPOSE

We evaluated the effect of chlorhexidine (CHX) 0.12% rinses on the clinical and microbiologic manifestations of oral candidiasis in HIV-infected children.

STUDY DESIGN

This was a cross-sectional, clinical intervention study of 38 HIV-positive children. Inclusion in the study was based on oral examination and positive oral culture for Candida. At baseline, subjects with no clinical lesions but who were culture-positive for Candida (N = 9) were placed on preventive therapy of CHX q.d. for 90 days. Subjects with clinical oral candidiasis (N = 9) were placed on therapeutic CHX b.i.d. All 38 subjects received oral exams at monthly intervals. At 90 days oral mucosal samples were again taken for Candida. Colony-forming units (CFU) were determined before and after CHX treatment.

RESULTS

Of 18 culture-positive subjects, 12 were included in the CFU analyses. After 3 months of CHX oral rinse therapy, Candida was undetectable in 3 children; another 8 showed an average 2-fold reduction in CFU. In 1 child the number of CFU increased modestly. Overall, the average pre- and posttreatment mean CFU was 6.18 +/- 2.19 and 2.73 +/- 3.15, respectively (P = .009). Five patients with clinical oral candidiasis at baseline, including all 3 who had pseudomembranous candidiasis, were free of signs of disease at the end of the study.

CONCLUSIONS

This study suggests that the topical disinfectant CHX may be a promising agent for treating and preventing oral candidiasis in HIV-infected children.

Human salivary histatin 5 fungicidal action does not induce programmed cell death pathways in Candida albicans

Salivary histatins (Hsts) are potent candidacidal proteins that induce a nonlytic form of cell death in Candida albicans accompanied by loss of mean cell volume, cell cycle arrest, and elevation of intracellular levels of reactive oxygen species (ROS). Since these phenotypes are often markers of programmed cell death and apoptosis, we investigated whether other classical markers of apoptosis, including generation of intracellular ROS and protein carbonyl groups, chromosomal fragmentation (laddering), and cytochrome c release, are found in Hst 5-mediated cell death. Increased intracellular levels of ROS in C. albicans were detected in cells both following exogenous application of Hst 5 and following intracellular expression of Hst 5. However, Western blot analysis failed to detect specifically increased protein carbonylation in Hst 5-treated cells. There was no evidence of chromosomal laddering and no cytochrome c release was observed following treatment of C. albicans mitochondria with Hst 5. Superoxide dismutase enzymes of C. albicans and Saccharomyces cerevisiae provide essential protection against oxidative stress; therefore, we tested whether SOD mutants have increased susceptibility to Hst 5, as expected if ROS mediate fungicidal effects. Cell survival of S. cerevisiae SOD1/SOD2 mutants and C. albicans SOD1 mutants following Hst 5 treatment (31 micro M) was indistinguishable from the survival of wild-type cells treated with Hst 5. We conclude that ROS may not play a direct role in fungicidal activity and that Hst 5 does not initiate apoptosis or programmed cell death pathways.

A systematic review of the effectiveness of antifungal drugs for the prevention and treatment of oropharyngeal candidiasis in HIV-positive patients

OBJECTIVE

A systematic review of randomized clinical trials published between 1966 and April 2000 was undertaken to determine the strength of evidence for the effectiveness of antifungal drugs (nystatin, clotrimazole, amphotericin B, fluconazole, ketoconazole, and itraconazole) to prevent and treat oral candidiasis in human immunodeficiency virus-positive patients.

STUDY DESIGN

An automated database search identified 366 articles. Six met inclusion and exclusion criteria with respect to prophylaxis; 12 met criteria for treatment of oral candidiasis.

RESULTS

The evidence for the prophylactic efficacy of fluconazole is good, although insufficient to draw conclusions about the other antifungals. Evidence for treatment effectiveness is insufficient for amphotericin B but good for nystatin, clotrimazole, fluconazole, ketoconazole, and itraconazole.

CONCLUSION

Suggestions for strengthening the evidence base include the following: use of larger, more well-defined groups; control for immunologic status, viral load, history of oral candidiasis, past exposure to antifungals, baseline oral Candida carriage, drug interactions, and antiretroviral therapy; and consistent use of compliance monitors, fungal speciation, and susceptibility testing.

Pathology and clinical correlates in oral candidiasis and its variants: a review

Although Candida albicans is well recognised as the major agent of oral candidiasis, it is not clear why several variants such as pseudomembranous (PC), erythematous (EC) and hyperplastic candidiasis (HC) manifest in different individuals, sometimes singly and on other occasions, in combination. The present review focuses on recent histopathologic and immunocytochemical studies as well as the pathogenic attributes of the yeast, in an attempt to address the following queries. (1) Do histopathologic studies of the different variants of candidiasis in immunocompetent and immunocompromised individuals help explain these varying manifestations? (2) Under what circumstances does oral candidiasis manifest as a pseudomembranous rather than an erythematous lesion or vice versa? (3) Are there differences in immunoreactivity in closely adjacent mucosae so that the variable presentation of such lesions reflect differences in the local mucosal immune system? Recent studies of PC, EC and HC offer some insights into the pathogenic mechanisms involved. Histopathologic and immunohistochemical finding in cases of PC and EC in HIV-infected patients and controls appear to be comparable, with a marked reduction or even an absence of CD4+ cells. The latter phenomenon is marked in PC compared with the EC, and explicable in terms of a breakdown of the local immune response in the former, and a hypersensitivity reaction against Candida antigens in the latter. Hyperplastic candidiasis on the other hand could be considered a superficial cellular reaction against the pathogen, which cannot entirely be eradicated by the systemic or local host immune response. The virulent attributes of the fungus, such as the production of extracellular proteinases, do significantly differ within and between species and thereby play a contributory role in the genesis of the clinical variants. Although the available data do give a tantalising glimpse of the contributory mechanisms for the aetiopathology of PC, EC and HC, further research is warranted to elucidate response of the host to this ubiquitous fungal pathogen.

Clinical management of selected oral fungal and viral infections during HIV-disease

The purpose of this review is to describe current possibilities of management of selected fungal and viral oral opportunistic infections including oral candidiasis, herpes simplex type 1 and 2-related lesions (HSV1,2), oral hairy leukoplakia (OHL) and oral lesions associated with human papilloma viruses (HPV). Less common diseases such as cytomegalovirus infection or human herpes virus type 8 associated with Kaposi's sarcoma and others are not considered. In a number of instances lifelong therapy or prophylaxis has to be instituted. Antiretroviral combination therapy, also called highly active antiretroviral therapy (HAART), has considerably changed the frequency of oral lesions caused by opportunistic agents. A short description of the antiretroviral agents available including respective side-effects is presented.

In vitro activities of antimicrobial agents against Candida species

OBJECTIVE

Antimicrobial mouthrinses may represent a valid alternative to topical antifungal agents. However, the action of antimicrobials could be affected by the different ingredients incorporated into mouthrinse products. The purpose of the present study was to investigate the in vitro antifungal and fungicidal activities of antimicrobials alone.

STUDY DESIGN

A broth macrodilution method was used to determine the minimum inhibitory concentration of 4 antimicrobial agents against Candida species. Minimum fungicidal concentration was also determined.

RESULTS

All antimicrobials showed antifungal activity against all tested organisms, but cetylpyridinium chloride received significantly lower minimum inhibitory concentrations (P < .005). Cetylpyridinium chloride also showed a greater fungicidal activity than chlorhexidine digluconate and hexetidine (P< .005), whereas sanguinarine chloride appeared to be less fungicidal against most of the isolates tested.

CONCLUSIONS

These findings suggest that cetylpyridinium chloride may be used as a topical antifungal agent. Clinical trials are now required to assess its value in the management of oral candidosis.

Triazole therapy for mucocutaneous candidiasis in HIV-infected patients

Mucocutaneous candidiasis, such as oropharyngeal candidiasis, esophageal candidiasis, and vulvovaginal candidiasis, are common problems in patients with HIV infection. These conditions adversely affect patient quality of life and morbidity status. New oral triazole agents provide improved treatment options for patients with these and other opportunistic fungal infections; however, the development of resistance in some Candida species poses new challenges. This article provides an overview of the diagnosis of mucocutaneous candidiasis, current treatment modalities, concomitant drug interactions, common adverse drug reactions, and the emergence of fungal resistance, and it suggests nursing interventions to maximize patient benefits from antifungal therapy.

Candidacidal activity of salivary histatins. Identification of a histatin 5-binding protein on Candida albicans

Candida albicans is the predominant species of yeast isolated from patients with oral candidiasis, which is frequently a symptom of human immunodeficiency virus infection and is a criterion for staging and progression of AIDS. Salivary histatins (Hsts) are potent in vitro antifungal agents and have great promise as therapeutic agents in humans with oral candidiasis. The molecular mechanisms by which Hsts kill yeast cells are not known. We report here, that unlike other antimicrobial proteins, Hsts do not display lytic activities to lipid membranes, measured by release and dequenching of the fluorescent dye calcein. Analysis of the magnitude and time course of Hst-induced calcein release from C. albicans cells further showed that loss of cell integrity was a secondary effect following cell death, rather than the result of primary disruption of the yeast cell membrane. 125I-Hst 5 binding studies indicated that C. albicans expressed a class of saturable binding sites (KD = 1 microM), numbering 8.6 x 10(5) sites/cell. Both Hst 3 and Hst 4 competed for these binding sites with similar affinities, which is consistent with the micromolar concentration of Hsts required for candidacidal activity. Specific 125I-Hst 5 binding was not detected to C. albicans spheroplasts, which were 14-fold less susceptible to Hst 5 killing, compared with intact cells in candidacidal assays. In overlay experiments, 125I-Hst 5 bound to a 67-kDa protein detected in C. albicans whole cell lysates and crude membrane fractions, but not in the yeast cell wall fraction. Consistent with the overlay data, cross-linking of 125I-Hst 5 to C. albicans resulted in the appearance of a specific 73-kDa 125I-Hst 5-containing complex that was not detected in the cell wall. 125I-Hst 5-binding protein of similar size was also observed in susceptible S. cerevisiae strain TI#20. This is the first description of Hst 5 binding sites on C. albicans which mediate cell killing and identification of a 67-kDa yeast Hst 5-binding protein. The binding characteristics of Hst 5 are in agreement with the observed potency of its biological effect and provide crucial information to the use of Hst 5 as a therapeutic agent. The presence of a specific C. albicans Hst 5-binding protein provides further insight into the potential mechanism of yeast killing and suggests a basis for differential activity between yeast killing and the nontoxic nature of Hsts to humans.

Fluconazole-resistant Candida species in the oral flora of fluconazole-exposed HIV-positive patients

The purpose of this study was to examine the effect of preceding fluconazole treatment on the oral mycologic flora and on the sensitivity of oral Candida albicans isolates to fluconazole. Saline oral rinses were collected from 89 HIV-positive patients, of whom 48 had been exposed to fluconazole and 41 were fluconazole-naive. The rinses were cultured on Sabouraud's and Pagano Levin agars, and yeasts were identified by standard methods. Fluconazole sensitivity of C. albicans isolates was measured by disk diffusion assay. C. albicans was isolated from 69% of patients who had received fluconazole and from 93% of the patients who were fluconazole-naive (p < 0.05). Nine other species of yeasts were also isolated, most commonly C. glabrata. Five patients previously exposed to fluconazole harbored fluconazole-resistant C. albicans, whereas no resistance was detected among the patients who were fluconazole-naive (p < 0.01). Sixteen of the patients who were fluconazole-exposed carried yeasts other than C. albicans, compared with only five patients in the fluconazole-naive group (p < 0.01). All of the fluconazole-resistant strains were isolated from patients with low CD4 counts (less than 100 cells/ml) and after lengthy fluconazole exposures. Nevertheless, patients in Charlotte, N.C., who had a greater mean fluconazole exposure time (10.25 +/- 1.41 months) than patients in Glasgow, UK, (0.65 +/- 0.18 months; p < 0.005), did not develop significantly more in vitro resistance or species diversity. This study indicates that long-term fluconazole treatment can have significant effects on the yeast flora of the mouth, particularly in a patient with a CD4 count of less than 100 cells/ml.

Shift from persistent oral pseudomembranous to erythematous candidosis in a human immunodeficiency virus (HIV)-infected patient upon combination treatment with an HIV protease inhibitor

A 45-year-old human immunodeficiency virus (HIV)-infected patient has suffered for a period of 4 years from recurrent and, later on, persistent oral pseudomembranous candidosis. The Candida isolates proved to be resistant to azole derivates in vitro and in vivo. Treatment with amphotericin B parenterally was successful in February 1996, but had to be stopped when chemotherapy for lymphoma was started. In August 1996, the patient showed a shift from the pseudomembranous to the erythematous type of oral candidosis; antiretroviral combination therapy including the HIV protease inhibitor saquinavir had been started 4 months previously. In July 1997, the patient was still suffering from a persistent oral candidosis of the erythematous type.

Role of dentinal carious lesions in the pathogenesis of oral candidiasis in HIV infection

The authors describe a clinicopathologic study that evaluated whether dentinal carious lesions are colonized by candidal organisms--and if so, whether there is a relationship between dentinal carious lesion colonization and clinical oral candidiasis, or OC, in HIV infection. Using light microscopy, the authors examined 30 extracted teeth with dentinal carious lesions from people in each of two groups: 30 consecutively treated HIV-positive patients and 30 consecutively treated HIV-negative patients. OC was diagnosed only in HIV-positive patients (40 percent). The dentinal carious lesion pattern in both groups was similar in occlusal, root and proximal caries. Candidal colonization of carious dentinal tubules was more frequent in HIV-positive subjects than it was in HIV-negative subjects. This research shows that it may be important to restore dentinal caries in HIV-infected patients to remove a protected niche for candidal organisms.

Oral manifestations of HIV disease: an update

More than 40 different oral diseases and conditions have been described in patients infected with human immunodeficiency virus (HIV). The recognition of the oral manifestations of HIV disease is of great significance because they may represent the first signs of the disease and have been shown to be highly predictive markers of severe immune deterioration and disease progression. Although some oral diseases and conditions have a weak association with HIV disease, others are strongly linked with the disorder, and a few are acquired immune deficiency syndrome (AIDS)-defining in nature. The spectrum of oral manifestations of HIV disease is reviewed with emphasis on clinical recognition, diagnosis, and treatment.

Periodontal implications: medically compromised patients

The presence of systemic disease in patients requiring periodontal therapy creates challenges for management. Alteration of treatment plans, with emphasis on physician consultation and preventive periodontal care, is frequently needed to minimize the impact of periodontal disease on the systemic condition. Conversely, detection and treatment of systemic disorders may impact upon the status of the periodontium and the success of periodontal therapy. The goal of holistic patient management is facilitated by a free flow of information between the patients and their medical and dental health care providers.

Clinical characteristics and management responses in 85 HIV-infected patients with oral candidiasis

Eighty-five consecutively seen HIV-positive persons with oral candidiasis were evaluated for clinical characteristics, staging of HIV disease, quantitation of candidal colony formation, and response to systemic antifungal treatment with Nizoral (ketoconazole). Fifty-five had CD4 counts less than 200. There was an inconsistent association between clinical signs, patient symptoms, CD4 counts, and candidal colony-forming units. However, there was a trend toward higher colony-forming unit counts (> 500) in patients with lower CD4 cells (< 200). Sixty-five patients had a complete clinical response to the ketoconazole treatment (200 mg daily for 7 days), even though 81% of posttreatment cultures remained positive. Nonsmokers were more likely to respond to antifungal treatment when compared with smokers, and there was a slight tendency for complete responses when colony-forming unit counts were low. The most common lesion presentation was a combination of the white (pseudomembranous) and red (erythematous) forms. Forty-nine percent had complaints of pain. The variable responses indicated the importance of flexible dose-time and drug considerations in antifungal management. Candida albicans was the predominant species.

HIV-related oral disease

Few people with HIV infection fall to experience oral lesions during the course of their disease. Oral mucosal and salivary gland manifestations include several that were not seen before the AIDS epidemic, while others are more severe in this population. Oral lesions reflect HIV status and the stage of immunosuppression, are important elements in HIV staging and classification schemes, raise pertinent questions about mucosal aspect of immunosuppression, and provide therapeutic challenges. Their pervasive nature and biological significance emphasise the importance of a careful oral examination as part of the general clinical evaluation.