Reduced red blood cell velocity in nail-fold capillaries as a sensitive and specific indicator of microcirculation injury in systemic sclerosis.
OBJECTIVE
To assess red blood cell velocity in finger nail-fold capillaries using video capillaroscopy in patients with SSc and other collagen diseases.


METHODS
This study included 127 patients with SSc as well as patients with SLE (n = 33), DM/PM (n = 21), RA (n = 13) and APS (n = 12), and 20 healthy subjects. Red blood cell velocity was evaluated using frame-to-frame determination of the position of capillary plasma gaps.


RESULTS
The mean red blood cell velocity was significantly decreased in patients with SSc compared to healthy controls (63.0% reduction) and patients with other conditions. Mean blood velocity was similar between patients with dcSSc and lcSSc. Importantly, even SSc patients with normal or non-specific nail-fold video capillaroscopic (NVC) patterns or a scleroderma early NVC pattern exhibited a significantly lower red blood cell velocity compared to healthy controls (51.7 and 61.4% reduction, respectively) or patients with other conditions, despite normal or mild capillary changes. Patients with the scleroderma active and late NVC pattern showed a more decreased blood velocity (65.5 and 66.2% reduction, respectively). This reduced blood velocity was significantly associated with NVC findings, including capillary ramification and capillary loss. Although remarkably reduced velocity was observed in SSc patients with intractable digital ulcers (72.1% reduction), it was significantly improved by lipo-prostaglandin E(1) (lipo-PGE(1)) infusion.


CONCLUSIONS
Our results suggest that reduced blood velocity is a hallmark of SSc. Furthermore, measurement of red blood cell velocity may be useful in evaluating therapeutic effects on microcirculation.
Mugii
Naoki
N
Department of Rehabilitation, Kanazawa University Hospital, Kanazawa, Japan.
Hasegawa
Minoru
M
Hamaguchi
Yasuhito
Y
Tanaka
Chihiro
C
Kaji
Kenzo
K
Komura
Kazuhiro
K
Ueda-Hayakawa
Ikuko
I
Horie
Sho
S
Ikuta
Munehiro
M
Tachino
Katsuhiko
K
Ogawa
Fumihide
F
Sato
Shinichi
S
Fujimoto
Manabu
M
Takehara
Kazuhiko
K
D000368:Aged; D001783:Blood Flow Velocity; D002196:Capillaries / Q000473:pathology*; D004912:Erythrocytes / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008833:Microcirculation; D020678:Microscopic Angioscopy / Q000379:methods; D008875:Middle Aged; D009262:Nails / Q000098:blood supply*; D012595:Scleroderma, Systemic / Q000473:pathology* / Q000503:physiopathology; D012680:Sensitivity and Specificity