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Published on: November 5, 2019
Hemoglobin sickle cell disease complications: a clinical study of 179 cases
François Lionnet1, Nadjib Hammoudi, Katia Stankovic Stojanovic
1Service de Médecine Interne, Hôpital Tenon, AP-HP, Paris. francois.lionnet@tnn.aphp.fr
Insights
Hemoglobin sickle cell disease is not a mild sickle cell anemia variant. It presents unique ophthalmological and otological issues, with lower vasculopathy prevalence. Phlebotomy effectively reduced acute events.
Area of Science:
- Hematology
- Genetics
- Internal Medicine
Background:
- Hemoglobin sickle cell disease (HbSC) is a common hemoglobinopathy.
- Often misclassified as a mild form of sickle cell anemia.
- Limited research exists on HbSC disease progression and complications.
Purpose of the Study:
- To update current knowledge on hemoglobin sickle cell disease.
- To characterize clinical and biological aspects of HbSC.
- To assess pulmonary arterial hypertension and nephropathy prevalence in HbSC.
Main Methods:
- Single-center study of 179 patients with HbSC.
- Collection of clinical and biological data.
- Focused assessment of pulmonary arterial hypertension and nephropathy.
Main Results:
- Diagnosis delay in 29% of adult patients.
- Acute events: vaso-occlusive crisis (36%), acute chest syndrome (20%), priapism (20%).
- Chronic complications: retinopathy (70%), otological disorders (29%).
- Low prevalence of nephropathy (13%), pulmonary hypertension (4%), strokes (1%).
- Phlebotomy in 36% of patients reduced acute events by 71%.
Conclusions:
- HbSC disease is distinct from sickle cell anemia, not a mild variant.
- Emphasize viscosity-associated otological and ophthalmological complications.
- Low prevalence of vasculopathy (strokes, pulmonary hypertension, ulcers, nephropathy).
- Phlebotomy shows promise in reducing acute events and warrants further investigation.
Background:
Hemoglobin sickle cell disease is one of the most frequent hemoglobinopathies. Surprisingly, few studies have been dedicated to this disease, currently considered to be a mild variant of homozygous sickle cell disease. The aim of this study was to update our knowledge about hemoglobin sickle cell disease.
Design And Methods:
The study involved a single center series of 179 patients. Clinical and biological data were collected with special attention to the assessment of pulmonary arterial hypertension and nephropathy.
Results:
Hemoglobin sickle cell diagnosis was delayed and performed in adulthood in 29% of cases. Prevalence of hospitalized painful vasoocclusive crisis, acute chest syndrome and priapism was 36%, 20% and 20%, respectively. The most common chronic organ complications were retinopathy and sensorineural otological disorders in 70% and 29% of cases. Indeed, prevalence of complications reported in homozygous sickle cell disease, such as nephropathy, suspicion of pulmonary hypertension, strokes and leg ulcers was rather low (13%, 4% and 1%, respectively). Phlebotomy performed in 36% of this population (baseline hemoglobin 11.5 g/dL) prevented recurrence of acute events in 71% of cases.
Conclusions:
Our data suggest that hemoglobin sickle cell disease should not be considered as a mild form of sickle cell anemia but as a separate disease with a special emphasis on viscosity-associated otological and ophthalmological disorders, and with a low prevalence of vasculopathy (strokes, pulmonary hypertension, ulcers and nephropathy). Phlebotomy was useful in reducing acute events and a wider use of this procedure should be further investigated.
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