Experimental investigations and clinical use of photodynamic therapy (PDT)in the Rudolfstiftung Hospital

This article addresses experimental investigations and the clinical use of PDT in the Rudolfstiftung Hospital, Vienna. We investigated mesotetrahydrox yphenylchlorine (mTHPC) and the photosensitizer hematoporphyrin derivative alone or in combination to prove photodynamic antibacterial effects on Stap hylococcus aureus (wild type). mTHPC showed antibacterial toxicity in the d ark; hematoporphyrin derivative showed suppressive growth effects only afte r white-light illumination. Photodynamic activity by the combination of bot h dyes was obtained in a roughly additive manner. Furthermore, we observed the development of resistance of erythromycin after the illumination proced ure with hematoporphyrin derivative. Wild-type S. aureus developed no resis tance to the other antibiotics tested. Furthermore, long-term follow-up exa minations proved mTHPC-mediated PDT as a possible adjuvant intraoperative t herapy in cases of relapses of gynecologic carcinomas. PDT is a tissue-sele ctive and simple intervention. It shows few side effects, and, therefore, i t reduces the overall burden of tumor patients. In another clinical investi gation, we used 5-aminolevulinic acid-based PDT to treat intraepithelial ne oplasia and human papillomavirus of the uterine cervix. 33 of 38 (86,8%) pa tients with superficial cervical intraepithelial neoplasia grades I and II were treated successfully with PDT. Eradication of human papillomavirus inf ections was successfully performed in 80% of the cases. Copyright (C) 1999 S. Karger AG, Basel.