Sickle-cell disease

Sickle-cell disease is a genetic disorder in which red blood cells may change shape under certain circumstances. This causes the cells to become stuck in capillaries which deprives the downstream tissues of oxygen and causes ischemia and infarction. The disease usually occurs in periodic painful attacks, eventually leading to damage of internal organs, stroke, or anemia, and usually resulting in decreased lifespan. It is common in people from countries with a high incidence of malaria, and especially in West Africa, or in descendents from those people.

Treatment

Febrile illness

Children with fever are screened for bacteremia - complete blood count, reticulocyte count and blood culture. Younger children (varies from center to center) are admitted for intravenous antibiotics while older children with reassuring white cell counts are managed at home with oral antibiotics. Children with previous bacteremic episodes should be admitted.

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Painful (vaso-occlusive) crises

Most patients with sickle cell disease have intensely painful episodes called vaso-occlusive crises. The frequency, severity , and duration of these crises vary tremendously, however. Painful crises are treated symptomatically with analgesics; pain management requires opioid administration at regular intervals until the crisis has settled. For milder crises a subgroup of patients manage on NSAIDs (such as diclofenac or naproxen). For more severe crises most patients require inpatient management for intravenous opioids; patient-controlled analgesia (PCA) devices are commonly used in this setting. Diphenhydramine is effective for the itching associated with the opioid use.

Related Topics:
Analgesic - Opioid - NSAID - Diclofenac - Naproxen - Patient-controlled analgesia - Diphenhydramine

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Acute chest crisis

Management is similar to vaso-occlusive crises with the addition of antibiotics (usually a third generation cephalosporin), oxygen supplementation for hypoxia, and close observation. Should the pulmonary infiltrate worsens or the oxygen requirements increase, simple blood transfusion or exchange transfusion is indicated. The latter involve the exchange of a significant portion of the patients red cell mass for normal red cells, which decreases the percent hemoglobin S in the patient's blood.

Related Topics:
Cephalosporin - Hypoxia

~ ~ ~ ~ ~ ~ ~ ~ ~ ~

Hydroxyurea

The first approved drug for the causative treatment of sickle cell anaemia, hydroxyurea, was shown to decrease the number and severity of attacks in a study in 1995 (Charache et al) and shown to increase survival time in a study in 2003. This is achieved by reactivating fetal hemoglobin production in place of the hemoglobin S that causes sickle cell anaemia. Hydroxyurea had previously been used as a chemotherapy agent, and there is some concern that long-term use may be harmful, but it is likely that the benefits outweigh the risks.

Related Topics:
Hydroxyurea - 1995 - 2003 - Fetal hemoglobin - Hemoglobin S - Chemotherapy

~ ~ ~ ~ ~ ~ ~ ~ ~ ~