Schönlein published few papers, and most of what is known of his achievements in nephrology comes from notes and publications of his students. It seems, however, that he described the combination of rheumatic fever, affection of internal muscular organs, a typical exanthem and oliguria, coining the name purpura rubra to describe this syndrome. Although patients with symptoms of Schönlein's syndrome had been described earlier, Schönlein was the first to describe purpura rheumatica as an entity. Schönlein's greatest contribution was the discovery of the anthropophilic pathogenic fungus Trichophyton schönleinii as the cause of the contagious skin condition favus (honeycomb ringworm). This opened a new field--mycology--and allowed therapy to be aimed specifically at the cause of the disease.