[ contribution of the myelogram in the diagnosis of blood diseases: about 291 cases]

The myelogram is considered one of the most valuable diagnostic tools for assessing hematological abnormalities. This work aims to clarify the indications of the myelogram in our context and to review the contribution of this examination to the diagnosis process. We present the results of a retrospective study, covering all myelograms performed in the hematology laboratory of the Avicenna military hospital in Marrakech. The prevalence of hematological diseases was 36% of all the studied myelograms. The indications were dominated by disturbances of the hemogram [66 %]. Of the 291cases reported, bone marrow plasmocytosis accounted for 15 % of pathologies diagnosed as compared to 9% of leukemias, 7% of megaloblastosis and 4% of myelodysplastic syndromes. Twenty two percent of the myelogram were reactive, while 31% of the samples were diluted and uninterpretable. The contribution of the myelogram to the diagnosis is subject to its good interpretation which highly depends on how good it was performed

[Current concept of the coagulation]

Coagulation is the whole of enzymatic reactions leading in transforming plasma into a gel primarily made up of fibrin to consolidate the clot formed during primary hemostasis. Fibrin derived from the enzymatic cleavage of fibrinogen by thrombin, a key enzyme of coagulation. The classic design of coagulation describes two different pathways: intrinsic and extrinsic. In fact these two ways are overlapping since passages exist between them. In this work we are interested in the current concept of coagulation physiology by underlining the place of the cellular reactions in this phenomenon. The phenomena of coagulation take place either in circulation, or on a cellular surface. The effectiveness of the enzymes implied in coagulation is much larger on a cellular surface than in plasma, bringing to conceive coagulation like a cellular phenomenon. Recently, this cellular conception of coagulation resulted in proposing a new sight of coagulation which would proceed in three phases: initiation, amplification, propagation