title: Evaluation of saliva flow rates, Candida colonization and susceptibility of Candida strains after head and neck radiation.
abstract: Hyposalivation is a long-term effect in patients receiving head and neck radiation. Radiotherapy can predispose oral colonization by Candida species of the mucosa. This study aims to evaluate the correlation between hyposalivation, measured by unstimulated saliva flow rates (SFR) and fungal colonization of the oral cavity, and also the resistance of isolated Candida strains to antimicrobial therapy. Fifty-three consecutive patients with radiotherapy were examined for late radiation damage on dental hard tissue and the salivary glands (SFR over a period of 5 min). The SFR were divided into three different values of hyposalivation: grade I (SFR 0.1-0.25 ml/min), grade II (SFR ≤0.1 ml/min), and grade III (SFR = 0.0 ml/min). Candidal colonization was defined using Sabouraud agar and identified using API 20C AUX (biomerieux) in the patients' rinsing water. Susceptibility was tested with Etest (amphotericin B, ketoconacole, voriconacole, and fluconacole). Hyposalivation grade I was detected in 23% (9.1 × 10(1) colony forming units (cfu); range, 200-5,900 cfu), hyposalivation grade II in 26% (4.3 × 10(1) cfu; range, 110-3,300 cfu), and hyposalivation grade III in 51% (2.0 × 10(3) cfu; range, 300-19,475 cfu) of patients. A significant correlation between the SFR and candidal colonization and clinical presentation (European Organization for Research and Treatment of Cancer (EORTC) score) was detected (Mann-Whitney test, p = 0.031). Twenty Candida albicans and 27 non-albicans species were identified. The resistance of C. albicans was higher than that of non-albicans strains against antimicrobial agents. By comparison, amphotericin B showed the greatest and fluconazole the least effect. A higher value of hyposalivation correlates with a higher risk of candidal colonization in patients who have received radiotherapy and also with a higher EORTC score. The spectrum of Candida is wide and susceptibility against antifungal therapy differs. In long-term examinations of patients with xerostomia after radiotherapy, the EORTC score can be used to measure hyposalivation. Reduced susceptibility of C. albicans might introduce complications to therapy. Findings of more non-albicans strains show a change in colonization which should be examined in further studies.
authors: Department for Oral and Maxillofacial Surgery, University Medical Center of the Johannes Gutenberg-University Mainz, Augustusplatz 2, 55131 Mainz, Germany. jkarbach@uni-mainz.de
authors: Julia
authors: J
authors: Karbach
authors: Christian
authors: C
authors: Walter
authors: Bilal
authors: B
authors: Al-Nawas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000666:Amphotericin B / Q000494:pharmacology; D000935:Antifungal Agents / Q000494:pharmacology; D002175:Candida / Q000187:drug effects / Q000254:growth & development / Q000528:radiation effects*; D002176:Candida albicans / Q000187:drug effects / Q000254:growth & development / Q000528:radiation effects; D015169:Colony Count, Microbial; D003731:Dental Caries / Q000209:etiology; D025141:Drug Resistance, Fungal; D005260:Female; D015725:Fluconazole / Q000494:pharmacology; D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D007654:Ketoconazole / Q000494:pharmacology; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D009055:Mouth / Q000382:microbiology / Q000528:radiation effects*; D011743:Pyrimidines / Q000494:pharmacology; D011832:Radiation Injuries / Q000209:etiology; D012463:Saliva / Q000378:metabolism / Q000382:microbiology / Q000528:radiation effects*; D012469:Salivary Glands / Q000528:radiation effects; D012636:Secretory Rate / Q000528:radiation effects; D014230:Triazoles / Q000494:pharmacology; D065819:Voriconazole; D014987:Xerostomia / Q000145:classification / Q000209:etiology
chemical_list: D000935:Antifungal Agents; D011743:Pyrimidines; D014230:Triazoles; D000666:Amphotericin B; D015725:Fluconazole; D065819:Voriconazole; D007654:Ketoconazole