Nailfold videocapillaroscopy in patients with deficiency of adenosine deaminase 2 (DADA2): a case-control study.

Abstract

Background: Deficiency of adenosine deaminase 2 (DADA2) is a rare monogenic autoinflammatory disease mainly characterized by the presence of systemic inflammation and vascular manifestations such as vasculitis and early-onset stroke. Raynaud's phenomenon (RP) can occur in up to 22% of DADA2 patients. The aim of this work was to investigate the microvascular status of DADA2 patients by the mean of nailfold videocapillaroscopy (NVC) comparing them with adequate healthy controls (HC) and primary RP patients.

Findings: NVC data of 9 DADA2 patients (mean age 18 ± 6 y) followed at the Children Gaslini Institute were retrospectively retrieved and compared to age and sex cross matched 11 HCs and 7 with primary RP patients. The NVC parameters were classified according to the EULAR SG Fast Track Algorithm and distinguished between scleroderma-pattern (giant capillaries and/or loss of capillaries combined with abnormally shaped capillaries) and non-scleroderma patterns (non-specific NVC alterations). In all DADA2 patients, NVC showed the presence of non-specific alterations (capillaries with dilations in 100% of cases, abnormal shapes in 23% and microhaemorrhages in 11% of patients). The capillary density was normal and no scleroderma pattern was found. Between DADA2, RP patients and HC, no significant differences in the rate of each microvascular finding were detected (p values NS).

Conclusions: This is the first report on NVC in DADA2 patients. Only non-specific abnormalities were found, characterized mainly by capillaries' dilations, but in the absence of giant capillaries. However, larger studies are needed to definitively disclose the microvascular status in DADA2 disease.