Lichenoid eruption due to hydrochlorothiazide. Diagnostic aid of macrophage migration inhibition factor (MIF) test.

The case of a lichenoid photosensitive eruption induced by hydrochlorothiazide is described. The macrophage migration inhibition factor test identified hydrochlorothiazide as the offending drug out of the several suspected drugs taken by the patient. It is suggested that an allergic reaction towards hydrochlorothiazide was involved in the development of the photosensitive lichenoid eruption in this case.