Successful Management of Milroy's Disease: A Rare Condition Complicated by Tuberculous Pericardial Effusion.

Milroy's disease is a rare hereditary primary lymphedema, typically presenting at birth or early infancy with chronic lower limb swelling due to mutations in the FLT4 gene encoding VEGFR-3. While congenital lymphedema is the hallmark, its association with tubercular pericardial effusion leading to tamponade is extremely rare. We report an 18-year-old female with longstanding bilateral lower limb lymphedema who presented with progressive dyspnea and fever. Evaluation revealed tubercular pericardial effusion, and genetic testing confirmed an FLT4 mutation. The patient improved with antitubercular therapy and supportive care. This case emphasizes the need to consider rare systemic complications in congenital lymphedema syndromes to optimize early diagnosis and management.