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It is a genetic disorder with an autosomal dominant inheritance pattern. Heterozygotes are clinically normal, although their neutrophils may be mistaken for immature cells which may cause mistreatment in a clinical setting. Homozygotes tend to have neutrophils with rounded nuclei that do have some functional problems.
Congenital Pelger–Huët anomaly
Is a benign dominantly inherited defect of terminal neutrophil differentiation secondary to mutations in the lamin B receptor gene. The characteristic leukocyte appearance was first reported in 1928 by Pelger, a Dutch hematologist, who described leukocytes with dumbbell-shaped bilobed nuclei, a reduced number of nuclear segments, and coarse clumping of the nuclear chromatin. In 1931 Huet, a pediatrician, identified it as an inherited disorder.
It is a genetic disorder with an autosomal dominant inheritance pattern. Heterozygotes are clinically normal, although their neutrophils may be mistaken for immature cells, which may cause mistreatment in a clinical setting. Homozygotes tend to have neutrophils with rounded nuclei that do have some functional problems. Homozygous individuals inconsistently have skeletal anomalies such as post-axial polydactyly, short metacarpals, short upper limbs, short stature, or hyperkyphosis. Identifying Pelger–Huët anomaly is important to differentiate from bandemia with a left-shifted peripheral blood smear and neutrophilic band forms and from an increase in young neutrophilic forms that can be observed in association with infection.
Acquired or pseudo-Pelger–Huët anomaly
Anomalies resembling Pelger–Huët anomaly that are acquired rather than congenital have been described as pseudo Pelger–Huët anomaly. These can develop in the course of acute myelogenous leukemia or chronic myelogenous leukemia and in myelodysplastic syndrome. It has also been described in Filovirus disease.  In patients with these conditions, the pseudo–Pelger–Huët cells tend to appear late in the disease and often appear after considerable chemotherapy has been administered. The morphologic changes have also been described in myxedema associated with panhypopituitarism, vitamin B12 and folate deficiency, multiple myeloma, enteroviral infections, malaria, muscular dystrophy, leukemoid reaction secondary to metastases to the bone marrow, and drug sensitivity, sulfa and valproate toxicities are examples. In some of these conditions, especially the drug-induced cases, identifying the change as Pelger–Huët anomaly is important because it obviates the need for further unnecessary testing for cancer. Peripheral blood smear shows a predominance of neutrophils with bilobed nuclei which are composed of two nuclear masses connected with a thin filament of chromatin. It resembles the pince-nez glasses, so it is often referred to as pince-nez appearance. Usually the congenital form is not associated with thrombocytopenia and leukopenia, so if these features are present more detailed search for myelodysplasia is warranted, as pseudo-Pelger–Huët anomaly can be an early feature of myelodysplasia.
- Hoffmann K, Dreger CK, Olins AL et al. (August 2002). "Mutations in the gene encoding the lamin B receptor produce an altered nuclear morphology in granulocytes (Pelger-Huët anomaly)". Nat. Genet. 31 (4): 410–4. doi:10.1038/ng925. PMID 12118250.
- Cunningham JM, Patnaik MM, Hammerschmidt DE, Vercellotti GM. Historical perspective and clinical implications of the Pelger-Hüet cell. Am J Hematol. Feb 2009;84(2):116-9
- Hoffmann K, Dreger CK, Olins AL, et al. Mutations in the gene encoding the lamin B receptor produce an altered nuclear morphology in granulocytes (Pelger–Huët anomaly). Nat Genet. Aug 2002;31(4):410-4.
- Vale AM, Tomaz KLR, Sousa RS, Soto-Blanco B. Pelger–Huët anomaly in two related mixed-breed dogs. J Vet Diag Invest. Jul 2011;23(4):863-5. |doi=10.1177/1040638711407891
- Gear JS, Cassel GA, Gear AJ, Trappler B, Clausen L, Meyers AM, Kew MC, Bothwell TH, Sher R, Miller GB, Schneider J, Koornhof HJ, Gomperts ED, Isaäcson M, Gear JH. Outbreake of Marburg virus disease in Johannesburg. Br Med J. 1975 Nov 29;4(5995):489-93
- NISHITH K SINGH, AND SANJAI NAGENDRA, the Mayo Clin Proc May 2008;83(5):600
- Vikramjit S Kanwar, MD, MBA, MRCP(UK), FAAP : Pelger–Huët Anomaly http://emedicine.medscape.com/article/957277-overview