Unilateral clubbing‐like digital thickening as a clinical manifestation of low‐flow vascular malformations: a series of 13 cases

Background Digital clubbing is a well-known clinical sign characterized by thickening of the distal phalanges of the fingers and toes. Unilateral clubbing occurs less frequently. A previous report showed for the first time two cases of unilateral clubbing as a clinical manifestation of lower limb venous malformation. The objective of the present study is to describe a series of 13 patients with a low-flow vascular malformation where a clubbing-like unilateral digital thickening is also observed. Methods All patients were retrospectively included after reviewing clinical photographs from a vascular malformations database. Results A total of 13 patients with low-flow vascular malformations were included in this study. The mean age at diagnosis was 11 years (range 5-26 years) with a female predominance (nine patients). The most frequent vascular malformation collected was a blue rubber bleb nevus syndrome in four patients, followed by common venous malformations in three patients. All patients characteristically exhibited a clubbing-like digital thickening. Seven patients had foot involvement and six patients hand involvement. Conclusions Although the number of cases is limited, our study is the first series of cases where a clubbing-like digital thickening is described in patients with a low-flow vascular malformation. The unilateral presence of clubbing or pseudoclubbing should lead to the suspicion of an underlying vascular malformation.