Detection of single and mixed colonization of Candida species in patients with denture stomatitis

Aim: To evaluate the profile of the colonization by Candida spp. using presumptive identification to classify the patients with denture stomatitis as having single or mixed colonization, correlating with oral and systemic status. Methods: The CHROMagar Candida™ Medium (CC) for yeast culture and exfoliative cytology was used to identify colonization by Candida spp. and distinguish the different species of the Candida genus from patients with denture stomatitis (DS) and denture wearers without DS (control group). In addition, colonization was correlated with specific habits, such as tobacco and alcohol use, as well as with the use of systemic drugs. Results: Direct swabbing of whole unstimulated saliva (WUS) and palatal mucosa revealed colonization in 97.3% of the patients with DS. In the control group, 55.0% patients presented colonization. The presumptive identification found C. albicans as the most prevalent between both groups, respectively in 89.4% of the DS group and 40.0% from the control group. Regarding the nonalbicans species in the DS group, the most frequent were C. krusei (31.5%), C. glabrata (21.0%) C. tropicalis (15.7%) and Candida spp (2.6%). Smokers presented 90% of mixed isolates, and no C.albicans single colonization in the DS group, with statistically significant difference between smokers and non-smokers (p=0.0051). In the control group, the non-albicans species were C.glabrata (23.0%) and C.tropicalis (23.0%). The results of cytology from the DS group showed positive results in 22.2% of the cases. Conclusions: The use of CC was effective as a complementary method for the diagnosis of colonization by Candida spp. and DS, with the additional advantage of enabling a rapid presumptive identification of the specie. Smoking seemed to play a role in the colonization of oral mucosa by mixed albicans and non-albicans species. Mixed colonization seems to be more prevalent between patients with DS.

Low-intensity red laser on the prevention and treatment of induced-oral mucositis in hamsters.

OBJECTIVE: The purpose of this study was to investigate the effects of laser phototherapy as preventive and therapeutic regime on induced-oral mucositis in hamsters. DESIGN: The animals were divided into four groups: preventive cryotherapy, preventive laser, therapeutic laser and therapeutic control group. Mucositis was induced in hamsters by intraperitoneal injection of 5-fluorouracil (5-FU) and superficial scratching. All preventive treatment was performed on the right cheek pouch mucosa. The left pouch mucosa was used for a spontaneous development of mucositis and did not receive any preventive therapy. Laser parameters were: lambda=660nm, P= 30mW, D=1.2J/cm(2), Deltat=40s, spot size 3mm(2), I=1W/cm(2). Cryotherapy was done positioning ice packs in the hamster mucosa 5min before 5-FU infusion and 10min afterward. To study the healing of mucositis, the left pouch mucosa of each of the hamsters in the TLG received laser irradiation on the injured area. Irradiation parameters were kept the same as abovementioned. The control hamsters in the TCG did not receive any treatment. The mucositis degree and the animal's body mass were evaluated. An assessment of blood vessels was made based on immunohistochemical staining. RESULTS: The CG animals lost 15.16% of theirs initial body mass while the LG animals lost 8.97% during the first 5 days. The laser treated animals had a better clinical outcome with a faster healing, and more granulation tissue. The quantity of blood vessels at both LG and CG were higher than in healthy mucosa. Regarding the therapeutic analysis, the severity of the mucositis in the TLG was always lower than TCG. TLG presented higher organization of the granulation tissue, parallel collagen fibrils, and increased angiogenesis. CONCLUSION: The results suggest that laser phototherapy had a positive effect in reducing mucositis severity, and a more pronounced effect in treating established mucositis.

Biotypes of Candida albicans isolates from the oral mucosa of HIV seropositive and control subjects / Biótipos de amostras de Candida albicans isoladas da mucosa oral de sujeitos HIV soropositivos e controles

Purpose: This study evaluated the Candida albicans biotypes from oral mucosa according to some host variables, such as HIV infection; medication use - protease inhibitors (PI), non protease inhibitors (NPI) or no medication (NM); dental prosthesis wearing (PW) or not (NPW); and yeast variables (activity levels of protease and phospholipase). Methods: Samples from the oral mucosa of 193 HIV+ subjects and 205 HIV- subjects were collected by means of sterile swabs and seeded onto Sabouraud dextrose agar. The isolates were identified by microculture on slide, germ tube formation, auxanogram, and zimogram. Ninety-two isolates were obtained from HIV+ individuals: 49 from patients under PI, 31 from patients under NPI and 12 from patients with no medication. The control group comprised 63 isolates from HIV- patients. Results: From the 95 possible C. albicans biotypes, 46 were identified in the sample, and the most prevalent were: 10122 (46.4%); 11122 (38.01%); 01031 (42.4%); 00022 (40%); (P<0.01 - Spearman correlation test). No difference was detected among PI, NPI, and NM groups. The control group exhibited intermediate enzymatic activity level from dentate isolates, and high protease activity level amongst isolates from prosthesis wearers.Conclusion: It was not possible to detect any inhibitory action of PI drugs on the enzymatic activity of C. albicans.

Objetivo: Este estudo avaliou biótipos de isolados de Candida albicans da mucosa oral utilizando-se variáveis do hospedeiro: infecção pelo HIV; medicação - uso de inibidores de protease (IP), não inibidores (NIP), ausência de medicação (SM); e uso ou não de prótese. Da levedura foram utilizadas as variáveis relativas à produção de protease e fosfolipase (nível de atividade). Metodologia: O material da mucosa bucal de 193 sujeitos HIV+ e 205 sujeitos HIV- foi coletado com swab estéril e semeado em Agar Sabouraud dextrose. A identificação dos isolados foi obtida pelos testes de micro cultivo em lâmina, tubos germinativos, auxanograma e zimograma. Utilizaram-se 92 amostras isoladas de indivíduos HIV+, sendo 49 de pacientes IP, 31 de pacientes NIP e 12 de pacientes sem uso de medicação (SM). O controle constou de 63 amostras isoladas de indivíduos HIV-. Resultados: Dos 95 diferentes biótipos possíveis, obteve-se 46, sendo os mais prevalentes: 10122 (46,4%); 11122 (38,01%); 01031 (42,4%); 00022 (40%); (P<0,01 - teste de correlação de Spearman). Não houve nenhuma diferença entre os subgrupos IP, NIP e SM. As amostras isoladas dos controles exibiram atividade intermediária de protease (dentados) e alta atividade de protease (portadores de próteses). Conclusão: Não foi possível constatar interferência dos IP na atividade enzimática de C. albicans.