Paroxysmal nocturnal hemoglobinuria

Paroxysmal nocturnal hemoglobinuria

Sangre y sistema linforreticular

Trastornos traumáticos, mecánicos y vasculares

Flashcards

Paroxysmal nocturnal hemoglobinuria

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Preguntas

Preguntas del estilo USMLE® Step 1

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A 33-year-old man comes to the primary care office because of fatigue, shortness of breath, pallor, and increased respiratory infections for the past six months. Temperature is 37.3°C (99.1°F), pulse is 86/min, respirations are 20/min, and blood pressure is 108/68 mmHg. Physical examination shows scleral icterus. Laboratory tests are obtained, and the results are shown below.  
 
 Laboratory value  Result  Reference Range 
 Hematologic   
 Hemoglobin  8.3 g/dL  13.5-17.5 g/dL 
 Mean corpuscular volume (MCV)   84 fL  80-100 fL 
 Platelet count  90,000/mm3   150,000-400,000/mm3  
 Leukocyte count  2,300/mm3  4,500-11,000/mm3  
   
Acidified serum lysis test is positive. Which of the following is a potential complication of this patient’s disease? 

Aspectos destacados

en inglés

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired, life-threatening condition characterized by the 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 functions to inhibit such immune reactions. Common symptoms of PNH are fatigue due to anemia, abdominal pain, and thrombosis, which is the major cause of death. There can also be jaundice from the accumulation of bilirubin, and characteristic dark-colored urine.

The management of PNH involves drugs like eculizumab, a monoclonal antibody that blocks the activity of the complement system, anticoagulation therapy in case of thrombosis, blood transfusion, and supportive management as needed.