It is a disease of children/ adults, and is characterized by fever and painful swelling of the joints, mostly of the limbs, especially of the ankles and knees. The notable feature of the painful swelling of the joints is that it is fleeting in nature i.e. the swelling of the joints travels from one joint to another. Simultaneously / soon, in acute stage, the heart may also be involved.

Hence, early diagnosis, or suspicion of the disease is necessary for proper treatment, especially to save the heart from damage. Hence, the warning signal of RF is that whenever fleeting pain/ swelling occurs in the joints, the physician must be consulted for a precise diagnosis. This signal should be recognized by parents/teachers especially, and adults should know about such diseases as a matter of routine.

A number of joints may be involved at one stage, and the other joints may also' be involved before swelling/pain in the earlier involved joints disappears. The swelling in the affected joints starts regressing' in about a week, and the joints may become normal in 3-4 weeks time.

The most important point is that the disease may be self-limited i.e. it may subside without any treatment. If such attacks continue to occur, although the joints heal completely during each attack, the most vital organ of the body i.e. the heart, may be damaged permanently.

What is the cause of RF?

The disease occurs as a result of sore throat by a specific organism called group A streptococcus. There is no direct extension of infection from the throat or from upper respiratory tract, either to the joints or to the heart. Both the joints and the heart are involved as a result of allergic response due to streptococcal infection in the throat, after a latent period of 7-10 days, during which antibodies to streptococci develop/ appear in the blood. It is thus an immunological disease, and of course, occurs in susceptible individuals.

The infection in the throat may be caused by a specific organism, i.e. group A streptococcus. Hence, all cases of sore throat may not result in this type of serious problem or disease.

What are the other parts of the body where the above allergic response occurs?

Besides the joints and the heart, the central nervous system may also be involved. The patient/child may get irregular, sudden, jerky type of movements at variable time/extent/ place. This manifestation of RF is called rheumatic chorea, and in this case there is an allergic inflammatory response of the basal ganglia lying in the brain. This may even occur independently, or with other manifestations of RF.

Further, the skin may also be involved as a result of an allergic response, called rheumatic subcutaneous nodules. These nodules which are quite hard lie just below the skin, causing no pain to the patient, and are about 0.1 to 2.0 cm in size. They appear mostly on bony areas of the body like the back of the hands and on the feet, patella etc., and may appear in numbers at a time. They may appear or disappear in no time and may recur in new areas as well. They mostly occur with other features of RF, especially with heart involvement.

Another manifestation of RF, though rarely seen in the tropics, is an allergic skin rash called erythem.a marginatum, which may appear in various circles. These circles may join giving various shapes to the lesion. The rash may also be fleeting at times, i.e. it may travel from one part of the skin to another, leaving no sign of involvement in the affected part. Like subcutaneous nodules, it is also mostly accompanied by cardiac lesion of RF. Both the subcutaneous nodules and rash may occur in the same patient. The rashes disappear completely as soon as the acute stage of RF is over. It occurs usually on the back of the patient and upper parts of both the upper and lower limbs.

Hence, from the above, it is clear that the various manifestations of RF, i.e. joint, heart, central nervous system, skin etc. involvement may occur independently, or in various combinations, and hence both the patient and the physician have to be quite vigilant in suspecting/early diagnosing the condition.

As regards a sore throat, it may not help in the diagnosis, as the manifestations of the disease occur after 7-10 days (latent period) of a sore throat, and even a history of sore throat may not be in the notice of the patient.