Microvascular abnormalities in skin capillaries of individuals with amyotrophic lateral sclerosis

This is the first study aimed to detect morphological abnormalities in vivo in the skin capillaries of amyotrophic lateral sclerosis patients (ALS). Videocapillaroscopy assessed subungueal capillaries in 28 ALS patients (cases) and 35 controls (p = 0.42). The mean age was 61.46 and 61.23 years, respectively (p > 0.99). No statistically significant differences were observed between the groups regarding dominant hand, arterial hypertension, dyslipidemia, diabetes mellitus, active smoker, and former smoker variables. 78.57% of cases had spinal onset and 21.43% bulbar. The median disease duration (time between the onset of symptoms and the date of videocapillarscopy) was 29.71 months. Dilated capillaries were detected in 17.8% of cases and 11.43% of controls (p = 0.49). The median of capillary diameter in cases was 10.15 µm and 8.72 µm in controls (p = 0.011). 35.71% of cases and 2.86% of controls had severe capillary tortuosities (p < 0.001). Ramified capillaries were observed in 46.43% of cases and 11.43% of controls (p < 0.002). Micro-hemorrhages were only observed in 10.71% of cases. No significant correlations were observed between disease duration and dilated capillaries, tortuosity, ramified capillaries, and micro-hemorrhages. The present in vivo study shows abnormalities in the skin capillaries of ALS patients that do not depend on disease duration.