CC Jan 2017 Paroxysmal Nocturnal Hemoglobinuria (PNH)

echoecho's version from 2017-05-08 03:25


Question Answer
PNH is an uncommon cause of _____ anemia, but missing the correct dx may put a patient in significant jeopardy?Hemolytic
*** PNH is an acquired hemolytic anemia, that is Coombs _____; the peripheral smear does NOT have _____ or ______ red cells?Negative; spherocytes; fragmented
*** PNH is a condition that is associated with _____, mostly venous, in unusual sites such as the _____ cavity and ____ veins?Thrombosis; abdominal; cerebral
In addition to thrombosis, its manifestations may include _____ and smooth muscle ____?Pantocytopenia; dystopia
The average age at dx is in the mid _____, with men and women affected equally?30's
This rare illness is caused by a somatic mutation in a gene on the ____ chromosome?X
PNH has been reported worldwide with no ____ or geographical factors that can be related to the development of this illness?Ethnic
There is intravascular _____ of RBCs in PNH?Lysis
The intravascular lysis of RBCs leads to what?1) Hemoglobinuria 2) loss of iron through the urine. 3) reduction in nitrous oxide (NO) that binds free hemoglobin. 4) a thrombotic state. 5) significant anemia
Episodes of hemolysis are triggered by?Infection; surgery; strenuous exercise, alcohol use
Hemolysis occurs more commonly at what part of the day?Night
List the symptoms of PNH?Severe fatigue, dyspnea, muscle cramps, chest pain, abdominal pain (reduction of nitrous oxide increases excessive smooth muscle contraction)
Other problems include thrombosis in ____% and renal damage in ___% of patients?20; 15
What is the most common cause of death in PNH, accounting for 40% of terminal events?Thrombosis
What lab test results are seen in PNH?1) retic count is elevated significantly. 2) LDH is 5-10 times normal. 3) unconjugated bilirubin is markedly increased. 4) haptoglobin is absent
DIagnosis is confirmed by what test?flow cytometry
All PNH cases are the result of a somatic mutation in the _____ gene, which is required as the first step in the cell membrane production of _____ and subsequent anchor protein biosynthesis?1) PIGA (phosphatidyl inositol glucan class A) 2) GPI (glycosylphosphatidylinositol)
Complement inhibitory proteins CD55 and CD 59 are low or absent on the cell surface of patients with clinical PNH, why?because they can't bind to the disabled GPI anchor membrane protein.
What does the severity of PNH depend on?on the % of RBC and WBC that have the acquired PIGA genetic mutation
Patients with more than ____% PNH white blood cells and /or > ___% PNH red cells will usually have active hemolysis requiring therapeutic intervention?50; 10
What is the treatment for patients with asymptomatic small clone (<10% PNH red cells)? can be observed and followed every 6-12 months for re-evaluation for clonal proliferation and increased hemolysis