Easy Pediatrics

Rheumatic fever is an autoimmune inflammatory disease that may develop after an infection with Streptococcus bacteria (such as strep throat or scarlet fever). The disease can affect the heart, joints, skin, and brain.

Acute rheumatic fever commonly appears in children between the ages of 6 and 15.

The illness is so named because of its similarity in presentation to rheumatism.

Rheumatic fever is common worldwide and is responsible for many cases of damaged heart valves.

Jones Criteria

Jones criteria are guidelines decided on by the American Heart Association to help doctors clinically diagnose rheumatic fever. Two major criteria or one major and two minor plus a history of a streptococcal throat infection are required to make the diagnosis of rheumatic fever.

The major criteria for diagnosis include

• arthritis in several joints (polyarthritis),
• heart inflammation (carditis),
• nodules under the skin (subcutaneous nodules or Aschoff bodies),
• rapid, jerky movements (Sydenham’s chorea), and
• skin rash (erythema marginatum).

The minor criteria include

• fever,
• high ESR (erythrocyte sedimentation rate, an laboratory sign of inflammation),
• joint pain (arthralgia),
• EKG changes, and
• other laboratory findings (elevated C-reactive protein, elevated or rising streptococcal antigen test).

Pathophysiology

Acute rheumatic fever is a sequela of a previous group A streptococcal infection, usually of the upper respiratory tract. This is an autoimmune response secondary to molecular mimicry following group A streptococcal pharyngitis.

The disease involves the heart, joints, central nervous system (CNS), skin, and subcutaneous tissues. It is characterized by an exudative and proliferative inflammatory lesion of the connective tissue, especially that of the heart, joints, blood vessels, and subcutaneous tissue. Continue reading »