A 4-year old boy presents with a history of left ankle joint swelling and pain for four days. It was preceded by an upper respiratory infection. On examination, the left ankle is swollen and tender. There is a petechial rash over the lower limbs. He is admitted two days later with bleeding per rectum. The most likely clinical diagnosis is:
Acute rheumatic fever Juvenile rheumatoid ahritis Pyogenic ahritis Henoch-Schonlein purpura