Clinical trial NCT04983654: Functional and Mechanistic Characterization of Limb Ulcers in Patients With Sickle Cell Disease
Official title: Functional and Mechanistic Characterization of Limb Ulcers in Patients With Sickle Cell Disease
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Ulcer
Anemia
Sickle Cell Disease
Keywords: limb ulcers
sickle cell disease
microcirculation
cytokine
wound fluid
Lead sponsor: Hospices Civils de Lyon
Sponsor class: OTHER
First posted: 2021-07-30
Enrollment: 70
Sex: ALL
Minimum age (years): 18
Maximum age (years): 130
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: 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.


Eligibility criteria: 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

Primary outcomes:
measure: Alteration of cutaneous microvascular function and peripheral sensorial neurological function in patients with limb ulcers
timeFrame: Day 1
Secondary outcomes:
measure: Modification of hemorheological red blood cells characteristics between patients with and without ulcers
timeFrame: Day 1
measure: Analysis of the composition of the wound fluid
timeFrame: Day 1
measure: Compare pro inflammatory markers in the blood between patients with and without ulcers
timeFrame: At initial visit
measure: Assessment of healing
timeFrame: through study completion, an average of 6 months
measure: Compare microcirculation, pro inflammatory marker in the wound fluid and in the blood and hemorheological characteristics after usual treatment to obtain healing
timeFrame: through study completion, an average of 6 months
Other outcomes:
Locations:
city: Lyon
country: France
facility: Groupement Hospitalier Edouard Herriot
Study officials:
affiliation: Service de Médecine Interne
name: Judith CATELLA, Dr
role: PRINCIPAL_INVESTIGATOR
References: