Paroxysmal nocturnal hemoglobinuria (PNH) is a chronic intravascular hemolysis caused by acquired defects in the red blood cell membrane, often worsening during sleep and may be accompanied by episodic hemoglobinuria and pancytopenia. Although rare, the incidence of this disease has shown an increasing trend in recent years. It is more common in northern China than in the south, with over half of cases occurring in young adults aged 20-40, and occasionally in those under 10 or over 70 years old. Males are more affected than females. The clinical manifestations of Chinese patients differ from those in Europe and America, with a more insidious and gradual onset, where anemia and bleeding are more common initial symptoms, while hemoglobinuria is less frequent at onset. In some cases, the disease presents acutely with infections, thrombosis, or aplastic anemia.

bubble_chart Diagnosis

(1) Medical history and symptoms

⑴ History inquiry: Note: ① History of jaundice, sudden onset of back pain, and severe abdominal pain. ② History of persistent headache, intermittent soy sauce-colored or meat wash-like urine.

⑵ Clinical symptoms: Dizziness, headache, lack of strength, shortness of breath, palpitation; shiver, fever, lumbago, chest tightness; hematuria or soy sauce-colored urine.

(2) Physical examination findings

Anemic appearance, jaundice of skin and sclera, grade I splenomegaly or normal.

(3) Auxiliary examinations

1. Blood test: Decreased hemoglobin, presenting as normocytic or microcytic hypochromic anemia; decreased or normal white blood cells and platelets; increased reticulocytes; increased spherocytes, easily observed red blood cell fragments, and presence of nucleated red blood cells.

3. Increased indirect bilirubin in blood, decreased or absent serum haptoglobin, increased plasma free hemoglobin. Positive urine hemosiderin.

4. Direct and indirect antiglobulin tests are both negative.

5. Positive acid hemolysis test, sugar water test, and snake venom factor hemolysis test.

(4) Differential diagnosis

1. Hereditary spherocytosis: Refer to autoimmune hemolytic anemia for key points of differentiation.

2. Glucose-6-phosphate dehydrogenase deficiency: Refer to autoimmune hemolytic anemia for key points of differentiation.

3. Autoimmune hemolytic anemia: Positive direct or indirect antiglobulin test.

4. Paroxysmal frigidity hemoglobinuria: Cyanosis of hands and feet after exposure to cold, improves with warmth; positive cold hemolysis test.

bubble_chart Treatment Measures

Iron: Ferrous sulfate 0.3, 2-3 times/day, or Fumafer 1 tablet once/day, orally. Folic acid 5-10mg, 3 times/day, orally.

Androgens: Stanozolol 2mg, 3 times/day, orally. Or testosterone propionate 100mg once/day, or nandrolone phenylpropionate 50mg twice/week, intramuscular injection.

Glucocorticoids: Hydrocortisone 100-200mg/day, intravenous drip, switch to prednisone 20-40mg/day orally after 3 days, treatment course 3-6 months.

6% Dextran: 500-1000ml/day, intravenous infusion. Used for acute hemolysis or abdominal pain crisis.

Blood transfusion: For severe anemia, washed red blood cells should be transfused.

For patients under 40 years old, allogeneic bone marrow transplantation should be performed if conditions permit.