PC1182: Systemic Capillary Leak Syndrome: An Important Cause for Edema and Hypotension

Introduction: Systemic capillary leak syndrome (SCLS) is a rare, life-threatening disorder described as recurring episodes of acute hypotension and edema, often requiring emergent care and hospitalization. Since it was first described in 1960, SCLS has been reported less than 500 times and primarily effects middle aged adults with an underlying monoclonal gamopathy. To date, roughly 25 cases have been reported in children.

Case Description: Our patient is a 12 year-old, medically complex female with hypoxemic ischemic encephalopathy with resulting cerebral palsy and refractory epilepsy as well as oropharyngeal dysphagia with G-tube dependence who was admitted with diffuse edema, hypotension, hypoalbuminemia and an increased hematocrit. Over the past nine months she had had several hospitalizations at another institution for similar presentations, each time preceded by mild viral infections. With every hospitalization she was also found to have severe hypoalbuminemia, and was diagnosed with a presumed protein losing enteropathy before being treated with albumin and diuretics to achieve euvolemia. In review of all outside records, however, there was no testing which confirmed either enteric or nephrogenic protein loss as all testing was found to be negative in these regards. After verifying these results through both stool and urine studies as well as ruling out other conditions including C-1 esterase deficiency, she was diagnosed with idiopathic systemic capillary leak syndrome and was started on monthly intravenous immunoglobulin (IVIG) infusions which is the preferred treatment for this condition. She has since had a profound improvement in both the frequency and the severity of these flares and remains on maintenance therapy.

Discussion: Systemic Capillary Leak Syndrome is a rare but life threatening condition which primarily effects middle aged adults and is therefore likely to be under diagnosed in the pediatric population. Though the pathophysiology remains elusive, the prevailing belief is that an unregulated inflammatory response leading to increased endothelial permeability and leakage of plasma proteins into the interstitial space is the primary driver for the severity of symptoms. A diagnosis of SCLS can be made based on the presence of hypotension, elevated hematocrit and hypoalbuminemia in the absence of other possible causes such as enteric or nephrogenic protein loss, infection or C-1 esterase deficiency among others. In the pediatric population, flares frequently follow mild viral syndromes but can lead to life threatening hypotension, rhabdomyolysis, respiratory failure and renal failure, and mortality rates for untreated patients has been estimated as high as 80% at five years. Treatment is largely preventative with monthly IVIG or theophylline plus verapamil, both of which have been shown to be effective and safe.

Conclusion: Systemic Capillary Leak Syndrome is a rare but important cause for edema and hypotension in the pediatric population with effective therapies aimed at decreasing mortality.