The Quiet Duel (movie, 1949)

Toshirō Mifune plays a young idealistic doctor who works at his father's (Takashi Shimura) clinic in a small and seedy district. During the war, he contracts syphilis from the blood of a patient when he cuts himself during an operation. Treating himself in secret and tormented by his conscience, he rejects his heartbroken fiancée without explanation.