In vitro studies on the antifungal effect of PUVA.

The effect of PUVA therapy upon 12 dermatophyte strains, 3 of Candida albicans, and 4 of mould fungi was evaluated by the agar dilution method on Sabouraud agar. 8-MOP, 30 microgram/ml medium plus UVA, 4 Joule/cm2 proved to be fungicidal dose to all the strains studied, with the exception of three of the mould fungi. For dematophytes and Candida albicans the MIC was between 1 and 3 microgram, 8-MOP plus UVA, 4 J; and 3 microgram when the UVA dose was reduced to 1--2 J. For mould fungi it was higher. The MFC varied within the range 2 to 30 microgram, when the UVA dose was fixed at 4 J. It reached 16 J when the dose of 8-MOP was kept at 4 microgram. The wide range in the MFC of the dermatophytes could be due to resistant colonies. 8-MOP alone had a distinctly inhibitory effect upon dermatophytes, but not upon Candida albicans or mould fungi.