Laboratory evaluation for the differential diagnosis of chronic myeloproliferative disorders includes all the following except- (AIIMS Nov 2012)
|B||Bone marrow aspiration|
|D||Determination of red blood cell mass|
These are a group of disorders characterized by proliferation of each or all of the precursors for myeloid elements – RBC, WBC and platelets.
Extra Edge: Myeloid erythroid Ratio:
It is the ratio of myeloid to erythroid precursors in bone marrow.
Normally it varies from 2:1 to 4:1.
An increased ratio is found in a. Infections b. CML c. Erythroid hypoplasia
Decreased ratio may mean a depression of leukopoiesis or normoblastic hyperplasia depending on the overall cellularity of the bone marrow.
Table - WHO Classification of Chronic Myeloproliferative Disorders (Ref. Hari- 18th ed., Pg. 898, table 108.1)
Chronic myelogenous leukemia
Chronic neutrophilic leukemia
Chronic eosinophilic leukemia
Chronic idiopathic myelofibrosis
Extra Edge: They may undergo transformation into acute leukemia.
Blood count reflects two processes
1. Proliferating cell line (may involve other myeloid elements also)
2. Marrow infiltration (may cause a decrease in normal cells0
1. Flow cytometry is not used in diagnosis
2. Flow cytometry is used in diagnosis of PNH.
3. MPD are diagnosed by BM examination.