Functional and Mechanistic Characterization of Limb Ulcers in Patients With Sickle Cell Disease (DrepanO2)

Civil Hospices of Lyon

Status: Completed

Conditions: Anemia; Ulcer; Sickle Cell Disease

Treatments: Diagnostic Test: patients with limb ulcers; Diagnostic Test: For patients without limb ulcers

Study type: Interventional

Funder types: Other

Identifiers

NCT04983654

69HCL21_0305

2021-A01605-36 (Other Identifier)

Details and patient eligibility

About

Sickle Cell Disease is the most frequent genetic disease in the world (representing one birth over 1900, in France). The polymerization of the abnormal hemoglobin (i.e., HbS) when deoxygenated is at the origin of a mechanical distortion of red blood cells (RBC) into a crescent-like shape. Sickled RBCs are very fragile and rigid, which lead patients to have severe anemia and to develop frequent and repeated painful vaso-occlusive crises. Furthermore, the repetition of sickling-unsickling cycles causes irreversible damages to the RBCs, which shorten their half-life. Accumulation of free hemoglobin and heme in the plasma is involved in blood vessels lesions in both the macro- and micro- circulation.

The resulting vascular dysfunction could explain why limb ulcers are 10 fold more frequent in patients with sickle cell disease compared to the general population and may happen at a younger age. Limb ulcers induce significant morbidity (delay of healing between 9 and 26 weeks in the french cohort), and are associated to significant pain (needing opioid pain-killer) and increase the risk of infection. Cost of care is also increased. Moreover, ulcers induce missed school and work days.

Data on cutaneous microcirculation and ulcers physiopathology in patients with sickle cell disease are scarce. We want to realise a microcirculatory and neurological functional study of patients with with and without ulcers and a characterization of biomarkers present in the blood or in the wound fluid which can participate to ulcers physiopathology.

To ensure healing, adapted therapeutics are essential. Several strategies are proposed such as: lifestyle measures (venous compression, lower limb elevation, rest), dressings, hyperbaric oxygenotherapy (also used in diabetic ulcers). The project is devoted to study the mechanisms involved in leg ulcers and the effects of therapeutical/behavioral strategies.

Enrollment: 70 patients

Sex: All

Ages: 18 to 130 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Sickle Cell Disease (homozygous SS or Sb0)
• Age ≥ 18 years old
• Consent patients
• Social regimen

Exclusion criteria

• tutela or curatella
• Vaso occlusive crisis < 1 month

Trial design

Primary purpose: Basic Science

Allocation: Non-Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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70 participants in 2 patient groups

Patients with limb ulcer

Experimental group

Description:

Patients with sickle cell disease and suffering from limb ulcer

Treatment:

Diagnostic Test: patients with limb ulcers

Patients without limb ulcer

Experimental group

Description:

Patients with sickle cell disease without any limb ulcer

Treatment:

Diagnostic Test: For patients without limb ulcers