The defective oral mucosal barrier due to the cytotoxic effect of chemotherapy and head and neck radiotherapy, in addition to the toxic effect of chemotherapy to the bone marrow result in the development of local or systemic infections.

Oral pseudomembranous candidiasis is the most common infection.
During head and neck radiotherapy, 30 to 40% or more of the patients will develop oral candidiasis.

Herpes simplex virus-1 infection complicates oral mucositis in about 20 - 30 % of the cases. In the different studies, HSV-1 infection complicates severe mucositis, grade 3 and 4, in almost 50% of the cases.

Oral mucosal infections prevent healing, cause early initiation of mucositis and increase its severity.

Selected references

1. Νικολάτου-Γαλίτη Ο και συν. Η καντιντίαση του στόματος σε ασθενείς με κακοήθη αιματολογικά νοσήματα. Αρχ Ελλην Ιατρικής 2003;20:58-65.
2. Nicolatou-Galitis O et al. Oral pseudomembranous candidiasis, herpes simplex virus-1 infection, and oral mucositis in head and neck cancer patients receiving radiotherapy and granulocyte-macrophage colony-stimulating factor (GM-CSF) mouthwash. J Oral Pathol Med 2001;30:471-480.
3. Aguirre JM & Nicolatou-Galitis O. Candidosis. 2004. www.eastman.ucl.ac.uk/-eaom.
4. Nicolatou-Galitis O et al. Effect of fluconazole antifungal prophylaxis on oral mucositis in head and neck cancer patients receiving radiotherapy. Support Care Cancer 2006;14:44-51.
5. Nicolatou-Galitis O et al. Herpes simplex virus-1 (HSV-1) infection in radiation-induced oral mucositis. Support Care Cancer 2006;14:753-762.