Skin blood flow in necrobiosis lipoidica diabeticorum.
BACKGROUND
Necrobiosis lipoidica diabeticorum (NLD) is a granulomatous skin reaction found in < 1% of diabetic patients. Our purpose was to determine if NLD represented areas of cutaneous ischemia.


METHODS
Using laser Doppler flowmetry, we measured cutaneous blood flow in nine diabetic patients at NLD lesions and at contiguous uninvolved sites. Flow values were also determined at several reference sites noncontiguous with the NLD lesions and compared to age- and sex-matched controls: 24 diabetic subjects without skin abnormalities, 18 diabetic patients with dermopathy, and 40 nondiabetic subjects.


RESULTS
NLD lesions exhibited significantly higher blood flow (4.8 +/- 0.7 ml/min/100 g) than areas of unaffected skin close to the lesions (1.2 +/- 0.1 ml/min/100 g) (P < 0.01 for both comparisons). There were no significant differences in flow between normal skin sites in NLD patients and normal sites in diabetic patients without skin lesions.


CONCLUSIONS
Our findings refute the hypothesis that NLD is a manifestation of microvascular ischemic disease of the skin. The increased blood flow seen in NLD lesions suggests an ongoing inflammatory process.
Ngo
Binh
B
Division of Dermatology, Department of Medicine, University of Nebraska College of Medicine, 98465 Nebraska Medical Center, Omaha, NE 68132, USA.
Wigington
Greg
G
Hayes
Kristie
K
Huerter
Christopher
C
Hillman
Brandon
B
Adler
Matt
M
Rendell
Marc
M
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D016022:Case-Control Studies; D048909:Diabetes Complications; D005260:Female; D006801:Humans; D007249:Inflammation / Q000503:physiopathology; D017078:Laser-Doppler Flowmetry; D035002:Lower Extremity / Q000098:blood supply*; D008297:Male; D008833:Microcirculation / Q000503:physiopathology; D008875:Middle Aged; D009335:Necrobiosis Lipoidica / Q000209:etiology / Q000503:physiopathology*; D012039:Regional Blood Flow; D012867:Skin / Q000098:blood supply*; D013696:Temperature