Paroxysmal cold hemoglobinuria (PCH) is a rare blood disorder in which the body's immune system produced antibodies that destroy red blood cells when they go from cold to warm temperatures.

Paroxysmal cold hemoglobinuria only occurs in the cold, and affects mainly the hands and feet. Antibodies attach (bind) to red blood cells and to proteins in the blood (called complements). These antibodies destroy the red blood cells as they they move through the body and get rewarmed. As the cells are destroyed, hemoglobin, the part of red blood cells that carries oxygen, is released into the blood and passed in the urine.

PCH has been linked to secondary syphilis, tertiary syphilis, and other viral or bacterial infections. Sometimes the cause is unknown.

The disorder is rare.

• Chills
• Fever
• Back pain
• Leg pain
• Abdominal pain
• Headache
• General discomfort, uneasiness, or ill feeling (malaise)
• Blood in the urine (red urine)

Laboratory tests can help diagnose this condition.

• Bilirubin and "bad" cholesterol (LDL) levels are high.
• Complete blood count (CBC) shows anemia.
• Coombs test is negative.
• Donath-Landsteiner test is positive.
• Level of hemoglobin in the blood is increased during attacks.

Treating the underlying condition can help. For example, if PCH is caused by syphilis, symptoms may get better when the syphilis is treated.

In some cases, medicines that suppress the immune system are used.

Persons with this disease often get better quickly and do not have symptoms between episodes. Usually, the attacks end as soon as the damaged cells stop moving through the body.

• Continued attacks
• Kidney failure
• Severe anemia

Call your health care provider if you have symptoms of this disorder. The doctor can rule out other causes of the symptoms and decide whether you need treatment.

Persons who have been diagnosed with this disease can prevent future attacks by staying out of the cold.

Schwartz RS. Autoimmune and intravascular hemolytic anemias. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 164.