24 year old female
History of severe headache and seizers.
No history of hemorrhage or thrombosis.
No organomegaly.
CBC:
- WBC: 7.6 x103 /uL (Neutrophils: 4.6x103 /uL - Lymphocytes: 2.2x103 /uL - Monocytes: 0.5x103 /uL - Eosinophils: 0.25x103 /uL - Basophils: 0.05x103 /uL).
- HGB: 14 g/dL - MCV 81: fL -MCH 27: pG - MCHC:33%
- Platelet: 891x103 /uL
LDH: 218u/L (R.R.: 98-192)
Thrombocytosis (E.T. Vs secondary)
B.M. aspirate ; Giemsa
B.M. aspirate : Emperipolesis
B.M. biopsy ; H.&E.
Bone marrow aspirate:
Normocellular B.M. for age. Increased megakaryocytes mostly of mature forms with increased nuclear lobulation and nuclear segmentations. Emperipolesis* is occasionally seen. (See below)
Sheets of platelet aggregates are frequently seen.
JAK2 mutation , CALR, MPL & BCR-ABL workup are recommended.
Bone marrow biopsy:
Normocellular B.M. for age. The megakaryocytes are increased with atypical hyperlobulated forms. Cytogenetic workup is recommended.
The case is positive for JAK2 V617F mutation (Done in higher center).
The case is confirmed as Essential Thrmobocythaemia
*Emperipolesis is derived from the Greek (em – inside; peri – around; polemai – wander about) and was defined as “The active penetration of one cell by another which remains intact.” It differs from phagocytosis in that an engulfed cell exists temporarily within another cell and with an intact normal structure while in phagocytosis, the engulfed cell is destroyed by the protective action of lysosomal enzymes. The cells involved in Emperipolesis are mainly histiocytes and megakaryocytes but can also be seen in association with tumour cells and Reed Sternberg cells. In addition plasma cells, myeloid cells, erythroblasts and neutrophils can also be engulfed in histiocytes or megakaryocytes cell cytoplasm.
Rastogi V., et al. Emperipolesis - A Review. Journal of clinical diagnosis research. 8(12): ZM01-ZM02. Dec., 2014.