Your husband is an elderly person with longstanding history of Diabetes
He has cardiac and kidney
ailments. He is are on dialysis
He is suffering form orchitis(Inflammation and infection of the testis)
Diabetics are general prone for infection due to hyperglycemia
and decreased immune mechanism.
Control the blood sugar.
Start on insulins.
I.V antibiotic and
good wound care with help to control the infection.
Recurrence is more common due to anatomical reasons.