Hello Thank You for contacting HCM. There are multiple causes which include: Chronic Diseases like diabetes mellitus, chronic liver disease, peripheral arterial disease, Lymphatic obstruction Microorganisms (group A streptococci) Hospital acquired condition Hence multiple factors can cause this. As your husband was initially admitted for this treatment so his immune system was weak and disease reoccurred. Hope this answers your question. If you have additional questions or follow up questions then please do not hesitate in writing to us. Wishing him good health.