The Shaykh (Al-Mufid), may Allah سبحانه وتعالى support him, narrated to me from Abu Al-Qasim Ja'far ibn Muhammad, from his father, from Sa'd ibn Abdullah, from Ahmad ibn Muhammad, from Al-Husayn, from Fadalah ibn Ayyub and Safwan ibn Yahya, from Al-Ala ibn Razin, from Muhammad ibn Muslim, from one of the two (Imams) عليه السلام. He said: I asked Imam عليه السلام about a man who has sores that constantly bleed - how should he pray? Imam عليه السلام said: "He should pray, even if blood continues to flow."