Chronic leg ulcers are frequent and debilitating complications of sickle cell anemia. Inadequate blood supply has been postulated to be an important factor in their occurrence and delayed healing. Little is known about their microcirculatory and histopathological changes. We evaluated the microcirculation of lower extremity ulcers with laser speckle contrast imaging and infrared thermography, and obtained clinical and laboratory characteristics in 18 adults with sickle cell anemia and chronic leg ulcers. Skin biopsies were obtained in four subjects. Subjects had markers of severe disease, anemia, and high degree of hemolysis, inflammation and thrombophilia. Higher blood flow was present in the ulcer bed, lesser in the immediate periwound area, compared to an unaffected control skin area. Microscopic examination showed evidence of venostasis, inflammation, and vasculopathy. Blood vessels were increased in number, had activated endothelium and evidence of thrombosis/recanalization. High blood flow may be due to chronic inflammation, cutaneous vasodilatation, and involvement of arterio-venous anastomosis. These changes in skin microcirculation are similar to chronic venous ulcers in the non-SCD population, thus suggesting that leg ulcers may be another end-organ complication with endothelial dysfunction that appears in patients with SCD at a younger age and with higher frequency than in the general population.

Project Start
Project End
Budget Start
Budget End
Support Year
3
Fiscal Year
2013
Total Cost
$28,335
Indirect Cost
Name
National Institute of Biomedical Imaging and Bioengineering
Department
Type
DUNS #
City
State
Country
Zip Code
Roche, Véronique Pasquale; Mohamad-Djafari, Ali; Innominato, Pasquale Fabio et al. (2014) Thoracic surface temperature rhythms as circadian biomarkers for cancer chronotherapy. Chronobiol Int 31:409-20
Minniti, Caterina P; Gorbach, Alexander M; Xu, Dihua et al. (2014) Topical sodium nitrite for chronic leg ulcers in patients with sickle cell anaemia: a phase 1 dose-finding safety and tolerability trial. Lancet Haematol 1:e95-e103
Minniti, Caterina P; Delaney, Kara-Marie H; Gorbach, Alexander M et al. (2014) Vasculopathy, inflammation, and blood flow in leg ulcers of patients with sickle cell anemia. Am J Hematol 89:1-6
Gorbach, Alexander M; Ackerman, Hans C; Liu, Wei-Min et al. (2012) Infrared imaging of nitric oxide-mediated blood flow in human sickle cell disease. Microvasc Res 84:262-9
Scully, Christopher G; Lee, Jinseok; Meyer, Joseph et al. (2012) Physiological parameter monitoring from optical recordings with a mobile phone. IEEE Trans Biomed Eng 59:303-6
Liu, Wei-Min; Maivelett, Jordan; Kato, Gregory J et al. (2012) Reconstruction of Thermographic Signals to Map Perforator Vessels in Humans. Quant Infrared Thermogr J 9:123-133