A Case Report of RASA1-Associated Inherited Lymphoedema with Recurrent Life-Threatening Lymphangitis

Background Most cases of lymphoedema are secondary to other causes, while cases of primary lymphoedema, in particular that of congenital origin, are uncommon. Limited genetic disorders are so far known to be associated with lymphatic malformation including mutations in RASA1. This clinical case highlights the possible complications of RASA1-associated lymphatic malformation in a female suffering from recurrent life-threatening septic lymphangitis. Case summary A 23-year-old female patient presented with congenital lymphoedema of the lower right extremity. At the age of eight she first suffered from an episode of lymphangitis. Thereafter, she developed recurrent episodes of lymphangitis predominately occurring during menstruation and culminating into severe and life-threatening septicaemias. Due to the menstrual association, endometriosis was suspected but could not be confirmed. Furthermore, angiography could not detect any sign of arteriovenous fistula. Single-Photon-Emission-Computed-Tomography confirmed absent major lymphatics of the right leg with severely impaired and prolonged dermal lymphatic backflow. Genetic testing identified a disease-causing variant in the RASA1 gene. Discussion To our knowledge, this is the first case of recurrent septic lymphangitis with close relation to menstruation in a female with RASA1-associated lymphatic malformation. Due to the possible de novo or somatic origin of a pathogenic variant, a genetic disease should be considered in spite of an unremarkable family history or a localised lymphoedema. Although there is no curative therapy available yet, the knowledge of the underlying genetic defect is important for interdisciplinary patient care and might be crucial for individual molecular therapies in the future.