Nail-fold capillaroscopy changes in patients with digital gangrene without connective tissue diseases or Raynaud’s phenomenon compared to the normal population

Abstract

This cross-sectional study examines the main causes and nail-fold capillaroscopy (NFC) alterations in patients with digital gangrene without underlying connective tissue diseases or Raynaud's phenomenon (RP), compared to a control group. Patients referred for NFC from 2011-2023 were included, excluding those with RP, connective tissue diseases, compression traumatic causes, and positive antinuclear antibodies. Out of the 31 patients and 31 age- and sex-matched healthy individuals, the causes of digital gangrene were identified in 18 patients (58%). Oral contraceptive pills (OCPs) emerged as the most common cause, followed by Buerger's disease, hyperhomocysteinemia, COVID-19, ulcerative colitis, cryoglobulinemia, cold agglutinin disease, frostbite, antiphospholipid syndrome, and renal failure with arteriovenous fistula thrombosis. Capillaroscopy changes were significantly higher in patients compared to controls (P < 0.001), with non-specific changes being more prevalent in patients (64.5%) than controls (6.5%). Microhemorrhages were the most common abnormality, followed by dilated and thrombosed capillaries. The study concludes that causes of digital gangrene in patients without connective tissue disease or RP vary widely, with OCP users accounting for a significant portion; however, a considerable number of cases remain unexplained. Capillaroscopy findings in these patients often reveal non-specific abnormalities, significantly differing from the control population. Further studies involving larger sample sizes would be valuable in providing additional insights into this condition.