What is one of the major Jones criteria for diagnosing rheumatic heart disease?

The major Jones criteria is a set of clinical findings that are used to diagnose rheumatic fever, which can subsequently lead to rheumatic heart disease. Joint involvement, specifically polyarthritis, is one of the key manifestations included in these criteria. In the context of rheumatic fever, polyarthritis typically presents as pain, swelling, and tenderness in multiple joints, often starting in the larger joints such as the knees and ankles, before possibly affecting smaller joints.

The presence of polyarthritis in a patient who has had a recent strep throat infection (usually Group A Streptococcus) significantly raises the suspicion for rheumatic fever and, consequently, rheumatic heart disease. This joint involvement is not only a classic symptom but also indicates systemic inflammation caused by the autoimmune response to the streptococcal infection.

Other conditions listed, such as asthma, hypertension, and diabetes mellitus, are not part of the Jones criteria and do not directly relate to the diagnosis of rheumatic heart disease. Asthma is a respiratory condition, hypertension is a cardiovascular risk factor, and diabetes mellitus is a metabolic disorder, none of which are indicative of the acute inflammatory response seen in rheumatic fever. Thus, joint involvement serves as a poignant marker of the inflammatory process associated with this disease.