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Paroxysmal nocturnal hemoglobinuria

Summary of Paroxysmal nocturnal hemoglobinuria
Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired, life-threatening disease of the blood characterized by destruction of red blood cells by the complement portion of the immune system. This destructive process is a result of a defect in the formation of surface proteins on the red blood cell, which normally function to inhibit such immune reactions. Since the complement cascade attacks the red blood cells throughout the circulatory system, the hemolysis is considered an intravascular hemolytic anemia. The major cause of death PNH is thrombosis.




Hematological system

Heme synthesis disorders
Coagulation disorders
Platelet disorders
Mixed platelet and coagulation disorders
Thrombosis syndromes (hypercoagulability)
Leukemoid reaction
Dysplastic and proliferative disorders
Plasma cell dyscrasias
Hematological system pathology review

Paroxysmal nocturnal hemoglobinuria


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High Yield Notes
13 pages

Paroxysmal nocturnal hemoglobinuria

15 flashcards

USMLE® Step 1 style questions USMLE

2 questions

USMLE® Step 2 style questions USMLE

1 questions

A 37-year-old man comes to the emergency department due to a history of dark tea-colored urine in the mornings which clears as the day progresses. He also reports severe abdominal pain, headaches, back pain and fatigue. Physical exam is unremarkable except for pallor. Blood is sent for analysis, the results of which are below:

Hemoglobin: 6.5 g/dL
White blood cell count: 4,000/mm3
Platelet count 95,000/mm3
Serum lactate dehydrogenase (LDH): 2240 U (normal <250 U)
Serum creatinine: 1.5 mg/dL.

The patient also has an increased reticulocyte count.

Which of the following is the most likely diagnosis?

External References