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Autor*: S. Valníček, Bára Jordanová
Description:
Girl, 16 y., familial occurence of May-Hegglin anomaly (MHA) in mother. MHA is a constant, hereditary (asutosomal dominant) occurence of Doehle inclusinos in neutrophilic granulocytes together with giant platelets (macrothrombocytes) , often with thrombopcytopenia, occasionally with subsequent haemorrhagic diathesis. Doehle inclusions are light blue-gray inclusions in neutrophilic granulocytes with 1-4 microns in diameter. As a secondary phenomenon without platelet defect they occur in neutrophilic leucocytosis in some cases of bacterial infection, often with coarse, toxic granulation of neutrophilic granulocytes, for instance in pneumonia, scarlatina and so on. First description of these inclusions springs by Doehle (1898) was in a case of measles. Firstly they were considered to be rests of immature cytoplasm, but electron microscopy revealed that the inclusions in MHS consist of aggregates of very fine, filamentous structures sometimes in a paracristalline arrangements. They are seen in
3-100 % of platelets in MH anomaly. MHA is believed to be associated with the MYH9 gene. Pathogenesis of the disorder had been unknown until mutations in the gene encoding for non-muscle myosin haevy chain IIA (MYH9) were identified (Saito et al., 2008). Cytoplasmic inclusion bodies in neutrophilic granulocytes in MHS are aggregates of non-mucle myosin heavy chain II A. They are not present in platelets, nor in giant platelets. MYH9 is found to be responsible for several related disorders with macrothrombocytopenia and leukocvyte inclusions, such as Sebastian, Fechtner and Epstein syndromes ( with features of deafness, nephritis and/or cataract.) All these three MHY9-related diseases are allelic and share a common haoplotype around the MYH9 gene on chromosome 22. Nowadeys the granulocyte inclusions in MHA are supposed to be morphologicaly similar to inclusions described by Doehle, but of different nature.
Zařazení*:
White blood cell disorder
Přílohy*:
Description: In the middle of a neutrophilic granulocyte you can see a paranuclear blue inclusion body among the neutrophilic granules, morphologicaly corresponding to Doehle body, typical for MHA granulocytes.
Description: Centrally in a neutrophilic granulocyte you can see a paragranular localised unclear light-blue inclusion body and in the lower part of the picture there is a giant platelet (macrophtopmbocyte). Both of these phenomenons are typical for MHA. 
Description: In both granulocytes on the picture you can see light-blue inclusion-bodies, typical for MHA neutrophilic granulocytes In the left cell it is localised in the center, in the right cell in its upper part.