Paroxysmal cold hemoglobinuria (PCH)

Alternative names

PCH

Definition

PCH is a rare blood disorder caused by antibody formation that destroys the red blood cell after a person is exposed to the cold.

Causes, incidence, and risk factors

Paroxysmal cold hemoglobinuria is a condition where antibodies are formed against a specific blood group. These antibodies bind the red blood cells and a cell-lysing blood protein called complement only in the cold, and usually in the extremities (hands and feet).

When the blood cells are rewarmed in the body, they are lysed (broken down). Hemoglobin is released in the blood and passed in the urine as blood cells are broken down.

The disease has been associated with secondary syphilis, Tertiary syphilis, and other infections (caused by viruses or bacteria). Sometimes the cause is unknown.

Recovery from the attacks occurs very quickly, and people with this disease do not experience symptoms between episodes. Usually, the attacks end as soon as the sensitized cells are gone from the circulation. The risk factors are viral infection and syphilis. The disorder is rare.

Symptoms

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

Signs and tests

• Positive Donath-Landsteiner test
  
• Serum hemoglobin increased during attacks
  
• Urine hemoglobin increased
  
• CBC shows anemia
  
• Coombs test is negative
  
• Bilirubin is elevated
  
• LDH is elevated
  

Treatment
No specific treatment exists for cases when the cause is unknown. Cases caused by Syphilis respond well to treatment for the underlying disorder.

Expectations (prognosis)

Many cases will resolve without treatment. In some people, the attacks may occur repeatedly for many years.