Background Deficiency of adenosine deaminase-2 (DADA2) is a rare form of autoinflammatory disorder with limited reported cases.

Objectives In this study, we have characterized the clinico-immunological, radiological and genetic characteristics of eight childhood-onset DADA2 patients. We aimed to compare these features between surviving and deceased patients.

Methods Demographic features, clinical characteristics, imaging findings, mutations and pharmacological treatments compared between surviving and deceased DADA2 patients.

Results Eight patients from seven families were enrolled. While five of them were still surviving, three of them had died due to various reasons. Median age of the patients at disease onset and diagnosis were 7 years (range 0.5–13 years) and 14 years (range 5–27years), respectively. The main clinical manifestations were cutaneous manifestations (7/8), recurrent low-grade fever (6/8), neurological involvement (6/8) and gastrointestinal involvement (5/8). All patients had increased acute phase reactants at presentation and also during flares. Until the diagnosis of DADA2, five patients have been followed-up with the diagnosis of PAN; two patients both with PAN and FMF, and one patient with CAPS and vasculitis. Demographic, clinical, neurological features and genetic mutations did not differ in surviving and deceased DADA2 patients. Deceased and surviving subjects differed in terms of medication usage after the diagnosis of DADA2. Anti-TNF alpha treatment has been initiated in 5 surviving patients soon after the diagnosis of DADA2. However, unfortunately three patients who have died, were able to use either a few doses of anti-TNF alpha treatment or none; one patient due to reluctance of patient and two patients due to establishment of a definite diagnosis with genetic analysis after the patients had died.

Conclusions Although this study includes limited number of patient, to our knowledge this study for the first time compares the phenotypic, genotypic and medication differences between surviving and deceased DADA2 patients. Anti-TNF alpha treatment seems to be very efficient and lifesaving in DADA2 patients.

References

1. Zhou Q, Yang D, Ombrello AK, et al. Early-onset stroke and vasculopathy associated with mutations in ADA2. N Engl J Med 2014;370(10):911–20.

2. Navon Elkan P, Pierce SB, Segel R, et al. Mutant adenosine deaminase 2 in a polyarteritis nodosa vasculopathy. N Engl J Med 2014;370(10):921–31.

3. Garg N, Kasapcopur O, Foster J, et al. Novel adenosine deaminase 2 mutations in a child with a fatal vasculopathy. Eur J Pediatr 2014;173:827–30.

References

Disclosure of Interest None declared