15 Granulocyte function in affected individuals appears to be normal. However, nuclei of neutrophils in patients with PHA are not segmented due to a complete or partial lack of functional LBR. 14 LBR is an inner nuclear membrane protein that anchors the lamina and the heterochromatin to the inner nuclear membrane and has been shown to be significant for the normal morphologic maturation of granulocytes. 13 The lamin B receptor is an evolutionary conserved, multifunctional protein. 3 It has been reported that the lamin B receptor (LBR) mutations are the cause of PHA in humans. The nucleus is bounded by a membrane system called the nuclear envelope (NE), which consists of outer nuclear membrane (ONM) and the inner nuclear membrane (INM). Its distinct nuclear shape facilitates rapid diapedesis through vessel walls and chemotaxis through interstitial spaces, respectively. The human neutrophil has a lobulated nucleus containing condensed chromatin. 11 Presumed homozygous individuals have ovoid neutrophil nuclei, as well as varying degrees of developmental delay, epilepsy and skeletal abnormalities. An incidence of one in 6000 is reported by Ayan et al. 9 In humans, it is found rather rarely in a heterozygous state, according to Shetty et al. The PHA is also present in other mammals such as mice, 5 dogs, 6 cats, 7 horses 8 and rabbits. 5 The distribution of the anomaly is worldwide. In humans the PHA prevalence is between 0.01% and 0.1%, the anomaly affects the white people, black and Asian in all ages and in equal ratio between males and females. The Pelger-Huët anomaly is considered to be a familial anomaly and it is not connected with any pathologic state. Huët realize that the aberrant neutrophil morphology was a benign autosomal dominant inherited and surely not acquired change associated with a poor prognosis for tuberculosis. 3 Moreover, while examining smears of peripheral blood showed the Pelger anomaly in several of the child’s relatives. 4 In fact, Huët was pediatrician and he recognized the “Pelger anomaly” in a 7-year-old girl with tuberculosis who recovered from her illness. 3 Only three years later, Huët, who was also a Dutch, pronounced it as an inherited disorder. Pelger believed that the anomaly was associated with a poor prognosis in patients with tuberculosis because both patients died. Observed neutrophils had bilobed nuclei, but also a coarse clumping of the nuclear chromatin. 2 The neutrophil with characteristic appearance was first reported in two patients diagnosed with disseminated tuberculosis in 1928 by a Dutch hematologist-Karl Pelger. The nuclear shape of affected granulocytes resembles bands, metamyelocytes or myelocytes however, the chromatin pattern appears aggregated and mature. 1 The PHA has distinctive nuclear hyposegmentation of not only neutrophils, but also other granulocytes and monocytes, as well. However, neutrophils hyposegmentation also occurs with Pelger-Huët anomaly (PHA). Nevertheless, finding a total leukocyte number within reference interval, presence of immature hyposegmented neutrophils in increased numbers (a left shift) suggests an inflammatory leukogram. Morphologic evaluation of leukocytes by microscopic examination of a blood film is an essential part of the complete blood count (CBC).
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