Lightning-Storm Periungual Capillaries in a Patient with Complex Regional Pain Syndrome Type I

Complex regional pain syndrome (CRPS) is characterized by chronic pain out of proportion to injury following trauma. CRPS most commonly results after crush-type injury to the hand and may be associated with various cutaneous symptoms believed to be driven by vasomotor instability. Existing reports in the literature have employed a range of methodologies to describe and evaluate cutaneous and vascular changes in CRPS, though there exists no current gold standard for diagnosis.

Here, we report a 71-year-old male with a 10-year history of CRPS who presented with abnormal capillaries on onychoscopy, demonstrating a "lightning-storm" pattern.

Previous studies have shown increased blood flow to the cutis in the early stage of CRPS, yet diminished cutaneous flow during the later stages. However, one study showed increased nail capillary diameter in patients with later stage CRPS. Due to a variety of reported clinical characteristics and a nonspecific clinic presentation, both the recognition and diagnosis of CRPS is difficult. Nail fold capillaroscopy may be a useful and accessible tool for evaluating patients with CRPS.