Hello, Thank you for asking at HCM. I understand your concern. If your father had sudden swelling and pain of joints with fever than there are few diagnosis that come to mind: infection which would effect one joint most of the cases, Gout/pseudogout which are very similar with pseudogout being the most likely diagnosis in this case because this one can effect several joints at a time with pain, swelling and fever and very common in elderly. They are both self limiting and are not serious. Treatment with anti-inflammatory drugs is the basis (Ibuprofen) and patient generally gets better within a couple of weeks or so. Hope this is helpful to you and answers to your question