Acute Rheumatic Fever:

a Reemerging Disease

Abstract

Introduction: Acute rheumatic fever (ARF) is a nonsuppurative complication of Streptococcus pyogenes (SP) infection. In Uruguay, the increased circulation of SP has led to the re-emergence of ARF.
Objective: To describe the clinical case of a pathology that requires a high index of suspicion for diagnosis.
Clinical case: A 2-year-old male presented with swelling and pain in the right knee and elbow of 24 hours’ duration. The patient had a fever of 39.6°C (axillary) the previous day. No history of trauma. Three weeks prior, he had febrile rhinopharyngitis and was treated irregularly with amoxicillin every 8 hours.
Physical Examination: Swelling and warmth in the right knee without redness. Pain upon flexion-extension of the right elbow, without inflammatory signs. Analitic: Hemoglobin 7.7 g/dL (normocytic and normochromic anemia), white blood cells 11,800/mm3, platelets 567,000/mm3. C-reactive protein (CRP) 58.5 mg/L, erythrocyte sedimentation rate (ESR) 75 mm/h. Knee ultrasound: 24 mm sub-quadriceps fluid
collection. Arthrocentesis: cloudy, yellowish fluid with abundant whitish sediment, LDH 267 U/L, glucose 0.71 g/L. The patient was admitted to moderate care and started on intravenous clindamycin. Fluctuations persisted in the knee without elbow involvement. Synovial fluid culture, blood culture, and bacterial culture of the throat was negative. Antistreptolysin O (ASO) antibodies were 10,800 IU/ml. Electrocardiogram,
echocardiogram, and chest X-ray were normal. Following a diagnosis of rheumatic fever, treatment with acetylsalicylic acid (ASA) and intramuscular benzathine penicillin was begun.Complete resolution of arthritis was achieved. The patient was discharged on ASA and monthly prophylaxis with intramuscular benzathine penicillin.
Discussion: The diagnosis of ARF was based on elevated ASO levels combined with one major criterion (polyarthritis) and two minor criteria (fever, elevated CRP/ESR). In the current epidemiological context, it is necessary to suspect ARF, which will facilitate early diagnosis and appropriate treatment.