I had untreated scarlet fever when i was a child. i have had heart palpitations and i suffer from joint pain all the time. how do i know it's from sf?

Characteristic echo: An echocardiogram can easily diagnose the type of damage Scarlett fever causes, even many decades later. Generally, a single bout doesn't cause heart damage, but multiple bouts can. Regardless, an echo is indicated to evaluate your palpitations, regardless of cause, so that's a good starting place. SF causes joint pain during the infection, but not years later.