Exam 17: Hemolytic Anemia: Membrane Defects

A 5-year-old boy is admitted to the pediatric unit with a fractured tibia.Routine blood work is ordered.His PB smear shows moderate spherocytosis.An osmotic fragility is also ordered,and the test result indicates an increased osmotic fragility.Based on these findings,what is the most likely defect?

Which of the following causes horizontal interactions of skeletal protein abnormalities?

Explain how a somatic mutation in the PIGA gene leads to PNH.

Which of the following statements best describes the function of DAF in the body?

The screening sucrose hemolysis (sugar-water)test is useful in identifying PNH cells by what mechanism?

The SAO variant of HE is associated with:

A sample has the following test results: hemoglobin 9 g/dL,autohemolysis increased after 48 hours,and increased hemolysis observed with the Ham test and sucrose hemolysis test.Based on these findings,what is the patient most likely suffering from?

Hereditary pyropoikilocytosis differs in red cell morphology from other erythrocyte membrane defects by what characteristic cell shape?

The laboratory professional notes about 20% spherocytes on a peripheral blood smear of a 4-year-old boy.An osmotic fragility test is performed.The control shows initial hemolysis at 0.50% NaCl and complete hemolysis at 0.35% NaCl.The patient sample has initial hemolysis 60% NaCl and complete hemolysis at 0.45% NaCl.What does this indicate?

PNH is currently detected in the lab by which of the following?

What is the principal confirmation test in the diagnosis of HS?

In PNH,cells are susceptible to complement-induced lysis.This is thought to result from the lack of what two regulating factors?

Explain why patients with HS typically have an MCHC >36%.

Paroxysmal nocturnal hemoglobinuria has four basic disease mechanisms: hyperhemolysis,venous thrombosis,infection,and bone marrow hypoplasia.Which of these mechanisms is the most severe complication?

Which of the following disorders has an abnormal erythrocyte membrane that is abnormally permeable,resulting in the loss of K+ and water and decreased deformability?

Which of the following sets of disorders is characterized by increased osmotic fragility?