Pseudo Pelger-Huët anomaly
Neutrophils with the pseudo Pelger-Huët anomaly share the typical bi-lobed nuclear appearance but tend to occur at lower frequency (<10% of cells) and when these appearances arise in haematological disease the cells will generally have additional features reflecting the underlying cause.
Images of pseudo Pelger-Huët cells
Cells with the typical nuclear shape of true Pelger-Huët cells, but arising in the context of a myeloid neoplasm (most frequently MDS, but also AML or myeloproliferation). Pseudo Pelger-Huët cells shown here are in the company of blast cells (image 1). Dysplastic forms are shown, either with a monolobar nucleus (image 2) or with significant hypogranularity (image 3). The cells do not have to be hypogranular (image 4).
These arise predominantly in myelodysplasia, acute myeloid leukaemias and chronic myeloid leukaemia or other myeloproliferative conditions and are regarded as strong indicators of primary dysplasia. The clinical and morphological context is very important.
Although these morphological forms contribute significantly to diagnosis of haematological neoplasm they are not absolutely exclusive to neoplasia:
- The appearance may occur in the setting of immunosuppressive drugs or occasionally other medication, particularly following organ transplant (including haematopoietic stem cell transplant)
- Distinguish from true Pelger-Huët anomaly by clinical context, and the much higher frequency of Pelger-Huët cells in the inherited disorder