People with sickle cell disease can have problems that need care by a doctor right away, such as:

• Acute chest syndrome: This is caused by inflammation, infection, an blocked small blood vessels of the lung. Signs include chest pain, coughing, trouble breathing, and fever.
• Aplastic crisis: This is when the body temporarily does not make enough red blood cells, which can cause severe anemia. Signs include paleness, extreme tiredness, and a fast heartbeat.
• Hand-foot syndrome: This painful swelling of the fingers and toes (also called dactylitis ) is the first sign of sickle cell anemia in some infants.
• Infection: Kids with sickle cell disease are at risk for some bacterial infections. It's important to watch for fevers of 101°F (38°C) or higher, which can be signs of an infection. Get medical care right away if a fever happens.
• Priapism: Males with sickle cell disease can have painful, long-lasting erections. If it's not treated quickly, damage can cause problems with getting erections later in life.
• Splenic sequestration crises: The spleen traps the abnormal red blood cells and gets very large. This can lead to a serious, quick drop in the number of red blood cells in the bloodstream. Signs include paleness, weakness or extreme tiredness, an enlarged spleen, and belly pain.
• Stroke: Sickle-shaped cells can block small blood vessels in the brain, causing a stroke. Signs include headache, seizures, weakness in the arms and legs, speech problems, a facial droop, or loss of consciousness.

People with sickle cell disease are also at risk for problems such as leg ulcers, bone or joint damage, gallstones, kidney damage, and eye damage. Kids can have delayed growth and delayed puberty.

The frequency and severity of symptoms and problems varies a lot between different people with sickle cell disease.