Acute viral myositis: case report

Context: Benign Acute Childhood Myositis (BACM) is a self-limited syndrome of acute myalgia prevalent in calf with impaired walking after Upper Respiratory Tract Infection. This report analyze the clinical condition and investigation of BACM case, by medical record. Case report: C.L.F.A., male, 12 years, in use of clobazam, sodium divalproate, topiramate and lamotrigine, started low back pain. One day after, presented headache, fever and nasal congestion. Reported convulsive febrile episodes. At following morning received Upper Respiratory Tract Infection diagnoses. Next day, maintained symptoms and developed thrombocytopenia. Discharged due to suspicion of dengue. After 24 hours, returned with improved thrombocytopenia, also with leukopenia. At 5th day, started pain in lower limbs and impaired walking. Due to muscle symptoms worsening and increased creatinophosphokinase, hospital admission were indicated. Laboratory tests found increased in creatinekinase (10,180 U/L), CKMB (129,6 U/L), leukopenia (2800/mm3 ) and thrombocytopenia (174,000 / mm3 ). Anti-HIV, anti- leptospirosis, dengue, Chikungunya and anti-HCV tests resulted negative. At the 6th hospitalization day, he was discharged virtue of muscle symptoms, leukocytosis and creatinekinase levels favorable progression. Conclusions: BACM has excellent prognosis and self-limited course, so outpatient care is feasible. The diagnosis is clinical. If neurological deficits, modified urine tests and rash, or symptoms duration longer than one week, differential diagnoses must be researched. Measure creatinekinase is important if pain or walking disability after viral episode. Early intervention avoids complications.