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Pseudo-Pelger-Huet Anomaly or Pelgeroid change ( PPHA) is characterized by hyposegmentation of the neutrophil nucleus and chromatin clumping. 

Morphologic mimics of Pelger-Huet anomaly ( Psuedo-Pelger-Huet Anomaly)  are more common than the true disorder.The changes of hypolobation can be seen primarily in three circumstances associated with- 

1. Reactive conditions associated with severe infections,
2. Medications or drugs such as mycophenolate or valproate, 
3. Myelodysplastic syndromes or other myeloid stem cell disorders. 

Distinguishing true Pelger-Huet anomaly from mimics, though straightforward, is usually important as it may lead to unnecessary investigations like bone marrow examination.  

In the case of myelodysplastic syndrome (MDS) or other myeloid neoplasms, the hypolobation is often accompanied by hypogranulation of neutrophils, as well as other dysplastic changes seen in erythroid elements, platelets, and megakaryocytes. In particular, isolated isochromosome 17q is a cytogenetic abnormality specifically associated with these changes. 

In both reactive conditions and dysplastic-type changes, only a subset of neutrophils is usually affected, in contrast to the entire population in Pelger-Huet anomaly. Toxic changes of granulocytes may also be seen in cases associated with infection. 

Identification of drug-related cases requires knowledge of the clinical history and a high index of suspicion.

In Our case, 72 years old male patient presented with pancytopenia (Haemoglobin : 10.8 g/dl, leukocyte count : 3 × 10^9/L with and platelet counts : 29 × 10^9/L). 

Peripheral smear examination revealed 7-8% of the neutrophils having bi-lobed nuclei with condensed chromatin and hypogranulation of cytoplasm.

This morphology on peripheral smear examination in association with pancytopenia with no history of medication and infection was highly suggestive of Myelodysplastic syndrome.