Concato’s Polyserositis as a Manifestation of Tuberculosis in a Child: A Case Report

Description of Clinical Presentation: A 7-year-old female presented with sore throat, abdominal pain, fever, and vomiting persisting for a month. Initial laboratory tests showed leukocytosis, while autoimmune and infectious serologies were negative. Given persistent symptoms and signs of systemic inflammation, imaging was performed to further investigate the etiology.

Diagnostic Techniques and Their Most Important Findings: Chest CT revealed bilateral small pleural effusions, significant pericardial effusion, and minimal ascites. Transthoracic echocardiogram showed moderate-to-large pericardial effusion without hemodynamic compromise. Cardiac Magnetic Resonance Imaging (CMR) demonstrated pericardial thickening, enhancement of the pericardial leaflets, and mild-to-moderate exudative pericardial effusion suggestive of pericarditis. Due to high suspicion of tuberculous etiology, pericardiocentesis followed by surgical pericardiotomy was performed. Although pericardial fluid analysis was nonspecific and negative for acid-fast bacilli, pericardial biopsy confirmed granulomas with caseous necrosis. Anti-tuberculosis therapy was started with subsequent clinical improvement.

Learning Points from this Case: Concato’s polyserositis is a rare but severe manifestation of extrapulmonary tuberculosis, particularly in children. Diagnosis requires a high index of suspicion, especially in endemic areas, and imaging plays a central role. In this case, CMR findings were instrumental in guiding invasive diagnostic procedures. While pericardial fluid analysis may be inconclusive, histopathological examination remains essential for definitive diagnosis. Early recognition and appropriate treatment of tuberculous pericarditis can prevent complications such as constrictive pericarditis and improve outcomes.

Pericardial effusion
Pericardial thickening
Pericardial enhancement