Nivolumab-induced systemic capillary leak syndrome as an ultra rare life-threatening phenomenon of late toxicity and intravenous immunoglobulin efficacy.

ABSTRACT

Systemic capillary leak syndrome (SCLS) is a life-threatening disease. It is characterized by severe capillary hyperpermeability to proteins resulting in hemoconcentration, hypoalbuminemia and hypovolemic shock. Its treatment remains supportive, and the prognosis is generally poor. We report on a 51-year old male with melanoma treated with nivolumab for 1 year. 1 month following the completion of the treatment, the patient presented with signs of hypovolemic shock, anasarca, hemoconcentration and hypoalbuminemia. After excluding other diseases, a diagnosis of nivolumab-induced systemic capillary leak syndrome was made. A high dose of intravenous steroid therapy was promptly initiated without any significant clinical improvement. Intravenous immunoglobulin therapy was then administered with normalization of blood pressure, hemoconcentration and complete resolution of anasarca. Intravenous immunoglobulin should be considered a first-line treatment option for this rare phenomenon.

Lay abstract Systemic capillary leak syndrome (SCLS) is a life-threatening disease with a high fatality rate. Patients present with low blood pressure, widespread edema and rapid weight gain. Labs show low albumin levels with highly concentrated blood, seen as high hematocrit and hemoglobin levels. Current treatments aim to support the acute crisis. We are presenting on a 51-year old patient with melanoma, treated with nivolumab for 1 year who developed signs of SCLS 1-month following medication discontinuation. He was first treated with high-dose steroids without symptom resolution. He was then administered immune proteins called intravenous immunoglobulins, resolving all his symptoms. Due to the patient's complete response, we suggest intravenous immunoglobulins as the initial treatment in patients taking nivolumab presenting with SCLS.