Summary

The authors present a case of a 51-year-old woman with clinical diagnosis of mixed connective tissue disease and overlap systemic lupus erythematosus features, with a 6-month history of progressive painless abdominal distension. On examination, evident signs of ascites were present. Both the abdominal-pelvic ultrasound and CT scan confirmed a large amount of ascites. A diagnostic paracentesis was performed, which revealed typical features of chylous ascites (CA). An extensive diagnostic work-up led by a multidisciplinary team was performed, excluding malignancy, cirrhosis, infectious, as well as cardiac and primary lymphatic causes. The patient was kept under surveillance, with dietary therapy and periodic ascitic drainages. The hypothesis of an autoimmune cause for CA was considered by exclusion. Rituximab therapy was initiated and an excellent response was achieved, with reduction of the rate of accumulation of CA and an increase in quality of life of the patient.