Rapid lymphatic malformation expansion: Imaging, association with asymptomatic Streptococcus infection, multidisciplinary management, and therapeutic approach.

Lymphatic malformations are congenital anomalies of the lymphatic system that can occur anywhere in the body and typically present in early childhood. They are often painless, slow-growing, and asymptomatic, but may lead to a wide range of symptoms depending on their size and location. Rarely, congenital malformations may not be diagnosed until later in childhood or adolescence, despite being present from birth. In some individuals, lymphatic malformations can expand quickly, especially in the setting of an inflammatory process. We present the case of an 8-year-old boy who had a rapidly enlarging, nonpainful mass on his right neck and a positive streptococcus throat swab. After evaluation by multiple specialists and imaging studies, he was diagnosed with a multilocular, multicystic lymphatic malformation. He was treated with fluoroscopy-guided doxycycline sclerotherapy, and has had near total resolution of neck swelling. This case report is significant because it highlights the potential benefits of a multidisciplinary approach to the diagnosis and management of lymphatic malformations. Additionally, it emphasizes the importance of considering congenital malformations in the differential diagnosis of neck masses, even in older children. Finally, it also adds to the growing body of evidence that hypothesizes that strep throat infections may trigger the sudden expansion of previously asymptomatic congenital lymphatic malformations.