Intravenous Immunoglobulins Tapering and Withdrawal in Systemic Capillary Leak Syndrome (Clarkson Disease)

Background The systemic capillary leak syndrome (SCLS), also known as Clarkson disease, is a very rare condition characterized by recurrent life-threatening episodes of vascular hyperpermeability in the presence of a monoclonal gammopathy. Extended intravenous immunoglobulin (IVIG) treatment is associated with fewer recurrences and improved survival, but the optimal treatment dosage and duration remain unknown. Objective We aim to evaluate the safety of IVIG tapering and withdrawal in patients with SCLS. Methods We conducted a retrospective multicenter study including all adult patients with monoclonal gammopathy–associated SCLS from the EurêClark registry who received at least 1 course of IVIG. The primary end point was overall survival according to IVIG withdrawal. Results Fifty-nine patients of mean ± SD age 51 ± 13 years were included. Overall cumulative probabilities of 2-, 5-, 10- and 15-year survival were 100%, 85%, 72%, 44%, respectively. The IVIG was withdrawn at least once in 18 patients (31%; W+ group) and never in 41 patients (69%; W– group). Cumulative probabilities of 10-year survival in W+ versus W– groups were 50% and 83% (log rank test, P = .02), respectively. Relapse rate and the median number of relapses in the W+ versus the W– groups were 72% versus 58% (P = 0.3) and 2.5 (0.3–4) versus 1 (0–2) (P = .03), respectively. The IVIG tapering was not statistically associated with increased person-year incidence of attacks using a mixed linear model. Conclusions The IVIG withdrawal was associated with increased mortality and higher rate of recurrence in SCLS patients. The IVIG tapering might be cautiously considered in stable SCLS patients.