Hungry megakaryocytes on the hunt? An unusual case of extensive megakaryocyte emperipolesis

Keywords:
Megakaryocyte; Emperipolesis; Immune thrombocytopenic purpura

An 11-year-old female presented with fever and thrombocytopenia (Platelet count - 25 × 10⁹/L). Bone marrow smears revealed hyperplasia and emperipolesis in all megakaryocytes containing intact lymphocytes and neutrophils. (Figs. 1 and 2) No etiology was found. The patient was given intravenous immunoglobulin and steroids on presumption of Immune thrombocytopenia, to which she responded well (Platelet count after 4 months-108 × 10⁹/L).

Some emperipolesis may be seen in various disorders, including Immune thrombocytopenia.¹,² Aslan D postulated that, in ITP, emperipolesis contributes to megakaryocyte dysfunction and poor response to therapy.³ This is an unusual case where all megakaryocytes show extreme degree of emperipolesis, yet the patient responded well.

Figure 1
Bone marrow aspirate showing megakaryocytic hyperplasia with extensive emperipolesis; Geimsa stain, 400×.

Figure 2
Bone marrow aspirate showing a megakaryocyte with engulfed neutrophils and lymphocytes; Geimsa stain, 1000×.

REFERENCES

• ¹
  Cashell AW, Buss DH. Frequency and significance of megakaryocytic emperipolesis in myeloproliferative and reactive states. Ann Hematol. 1992;64:273-6.
• ²
  Rai S, Sharma M, Muhary M, Naik R, Sinha R. Increased emperipolesis in megakaryocytes in a case of idiopathic thrombocytopenic purpura. Indian J Pathol Microbiol. 2015;52:4523.
• ³
  Aslan D. Emperipolesis in immune thrombocytopenic purpura. Indian J Pathol Microbiol. 2009;52:289-90.

Publication Dates

• Publication in this collection
  29 Nov 2021
• Date of issue
  2021

History

• Received
  27 Aug 2020
• Accepted
  03 Dec 2020
• Published
  21 Dec 2020