Definition

Paroxysmal cold hemoglobinuria (PCH) is a rare blood disorder in which the body's immune system produces antibodies that destroy red blood cells. It occurs when the person is exposed to cold temperatures.

Alternative Names

PCH

Causes

PCH only occurs in the cold, and affects mainly the hands and feet. Antibodies attach (bind) to red blood cells. This allows other proteins in the blood (called complement) to also latch on. The antibodies destroy the red blood cells as they move through the body. 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.

Symptoms

Symptoms may include:

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

Exams and Tests

Laboratory tests can help diagnose this condition.

• Bilirubin levels are high in blood and urine.
• Complete blood count (CBC) shows anemia.
• Coombs test is negative.
• Donath-Landsteiner test is positive.
• Lactate dehydrogenase level is high.

Treatment

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.

Outlook (Prognosis)

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

Possible Complications

Complications may include:

• Continued attacks
• Kidney failure
• Severe anemia

When to Contact a Medical Professional

Contact your health care provider if you have symptoms of this disorder. Your provider can check for other causes of the symptoms and decide whether you need treatment.

Prevention

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

References

Michel M. Autoimmune and intravascular hemolytic anemias. In: Goldman L, Cooney KA, eds. Goldman-Cecil Medicine. 27th ed. Philadelphia, PA: Elsevier; 2024:chap 146.

Michel M, Jäger U. Autoimmune hemolytic anemia. In: Hoffman R, Benz EJ, Silberstein LE, et al, eds. Hematology: Basic Principles and Practice. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 47.