The Pseudo-Pelger HuËt Cell-A New Permanent Radiation Biomarker

Using archival peripheral blood slides obtained from patients in the 1958 Y-12 criticality accident, the authors have recently described the pseudo-Pelger Huët anomaly (PHA) in neutrophils as a new radiation-induced biomarker. The current work provides additional evidence that PHA is also a permanent biomarker, potentially useful in retrospective dosimetry. In the Y-12 cohort, the high dose group (n = 5, 2.98-4.61 Gy-Eq) exhibited 13.0 ± 0.85 % Pelger Huët cells (mean ± SEM) in the neutrophil population compared to 6.8 ± 1.6 % in the low dose group (n = 3, 0.29-0.86 Gy-Eq; p = 0.008). An age and gender-matched control group (n = 8) exhibited 3.6 ± 0.9 % PH cells. Results of a one-way ANOVA show that the high dose group is statistically different from both the low dose group and the control group (p = 0.002). In the Y-12 cohort, PHA appears <12 h post-accident and is permanent for more than 16 y. Similar long-term persistence of the PHA mutation has been obtained from examination of peripheral blood slides from the 1971 Co accident at the Variable Dose Rate Irradiation Facility (VDRIF) in Oak Ridge, TN. In order to investigate the pseudo-PH cell as a biomarker in animal studies under well controlled dosimetry, peripheral blood slides were obtained from animals in a nonhuman primate (NHP) (Macaca mulatta) total-body irradiation (TBI) model (Co γ rays at 0.6 Gy min; dose range 1-8.5 Gy, LD50/60 6.44 Gy). In the NHP studies, the first measurement of PHA is taken at 5 h post-irradiation, then daily for days 1-5 and every 5-10 d thereafter. In the TBI model, the PH cell appears quickly (<5 h) post-irradiation, and the dose-dependent PH percentage is constant from 1 d over the 60-d monitoring period of the experiments. Using the average of data from 1-60 d, a linear dose response (PHA % slope = 0.49 ± 0.07 % Gy, r = 0.92) is obtained over the dose range 0-8.5 Gy. The authors conclude that ionizing radiation induces dose-dependent internuclear bridges in circulating neutrophils, and this morphological change can be used both as an acute phase biomarker and as a tool for retrospective dosimetry.

Appearance of pseudo-Pelger Huet anomaly after accidental exposure to ionizing radiation in vivo

To evaluate the morphology of formed elements of human blood after exposure to ionizing radiation in vivo, archival smears of peripheral blood from eight individuals involved in the 1958 Y-12 criticality accident at Oak Ridge, Tennessee, were examined manually by light microscopy. For each case, increased interlobar bridging was observed in nuclei of the myeloid cells, many of which were bilobed and morphologically similar to Pelger Huet (PH) cells. The high-dose group (n = 5, 2.98-4.61 Gy-Eq) exhibited 13.0 ± 0.85% PH cells (mean ± SEM) in the neutrophil population compared to 6.8 ± 1.6% in the low-dose group (n = 3, 0.29-0.86 Gy-Eq; p = 0.008). An age- and gender-matched control group (n = 8) exhibited 3.6 ± 0.9% PH cells. Results of a one-way ANOVA show that the high-dose group is statistically different from both the low-dose group and the control group (p = 0.002). However, the low-dose group is not statistically different from the control group (p = 0.122). The mean number of nuclear lobes in blood neutrophils was also enumerated as a function of time after exposure and was found to be diminished, consistent with incomplete nuclear segmentation that is characteristic of the Pelger Huet anomaly (PHA). In contrast to these changes in myeloid cells, the morphology of erythrocytes and platelets appeared to be normal. The authors conclude that ionizing radiation induces abnormal morphology of circulating neutrophils, which is similar to the pseudo-PHA that is acquired in disorders such as myelodysplastic syndrome, acute myeloid leukemia, and leukemoid reactions. Potential molecular mechanisms by which radiation induces this morphological change are discussed. From this cohort, the biomarker appears to be present early post-accident (<9 h) and stable at least up to 16 y post-accident. Assessment of circulating pseudo-Pelger Huet cells is being investigated as a potential biodosimetric tool.

Pelger-Huët anomaly: a critical review of the literature

Pelger-Huët anomaly (PHA), an autosomal dominant haematological trait is characterised by neutrophil nuclear hypolobulation and modified chromatin distribution. Mutations in the lamin B receptor gene, a member of the sterol reductase family have been identified as the underlying cause. Due to its asymptomatic nature or lack of observer familiarity, PHA is often overlooked. In this review, we give an overview of the main pathophysiological, clinical, morphological and functional aspects of PHA. Furthermore, we highlight the importance of a comprehensive approach to the assessment of this laminopathy.

Historical perspective and clinical implications of the Pelger-Hüet cell

The unique historical aspects of Pelger and Huet's discovery of the Pelger-Huet cell highlight the diagnostic challenge that this morphologic finding presents to the physician. Making the diagnosis of the benign autosomal dominant anomaly is complicated by the morphologically similar pseudo-Pelger-Huet cell, which can signify underlying myeloid dsyplasia. This article relates the history of the Pelger-Huet anomaly as well as describes the clinical significance and diagnostic workup for the finding of a Pelger-Huet cell on peripheral smear.

Pelger-Huet anomaly: a case report

Impaired lobulation of neutrophils together with exaggerated clumping of chromatin, characteristic of Pelger-Huet anomaly was seen as an incidentalfinding in a 43-year old man who presented with depression. Peripheral blood and bone marrow findings and cytochemistry of the abnormal cells are described and the disease entity discussed.

White blood cell left shift in a neonate: a case of mistaken identity

We present a full-term male infant who presented with tachypnea and an increased band count on his complete blood count (CBC) with an immature to total neutrophil (I:T) ratio of 0.6 raising suspicion of early onset sepsis. A blood culture was drawn and he was started on appropriate antibiotics. The patient's clinical condition rapidly improved; however, the white cell count 'left shift' persisted. When a detailed family history was obtained, it was discovered that the father, paternal uncle and the grandfather had been diagnosed with Pelger-Huet anomaly (PHA). As the urine, blood and CSF cultures were all negative in this now well-appearing infant, the left shift on the CBC was believed to be due to inheritance of the PHA. We present this case to emphasize that even in this age of sophisticated laboratory evaluation, a good clinical history, including family history, and clinical evaluation, are essential for accurate diagnosis.

[Nuclear abnormalities in Pelger-Huet anomaly; progress in blood cell morphology]

Gene abnormalities responsible for familial Pelger-Huet anomaly have been recently discovered. Abnormalities in sequence of Lamin B Receptor(LBR) gene results in a lack of LBR protein that is essential for chromatin-binding to nuclear membrane. In neutrophils lacking LBR protein shows abnormal bilobular or monolobular nuclear forms and hyper-condensed chromatin-aggregation. We re-analyzed distribution of such Pelger-Huet anomaly in other cell lineages; we found that not only neutrophils but erythroblasts, monocytes, lymphocytes, plasma cells, eosinophils and basophils are also carrying chromatin-hypercondensation. One third of megakaryocytes are also binucleated like neutrophils. We compared neutrophil morphology between familial Pelger-Huet anomaly and so called pseudo-Pelger-Huet anomaly observed in patients with myelodysplastic syndromes(MDS) and acute myeloid leukemia(AML). The neutrophils in MDS were much similar to those of the familial anomaly, but neutrophils of AML, such as t (8;21) M2-AML and t (15;17) M3-AML, showed more heterogeneous pattern in lobulation and chromatin-hypercondensation. Especially in M3, differentiation-induction by all-trans retinoic acid induced a marked neutrophilia with pseudo-Pelger-Huet anomaly without chromatin-hypercondensation. Lack of LBR protein in familial Pelger-Huet anomaly results in hypolobulation and chromatin-hypercondensation in neutrophils, but in other cells such as erythroblasts and lymphocytes only chromatin-hypercondensation can be observed. In contrast pseudo-Pelger-Huet anomaly are more heterogeneous in morphology compared to the familial anomaly. The lack of leukemic or MDS transformation in the familial anomaly is a sharp contrast to the neoplastic nature of the pseudo-Pelger-Huet anomaly. In conclusion, our morphological recognition of certain abnormality of cells shows an marked progression when genetic abnormality responsible for some of them are discovered, and often make us recognize a further heterogeneity in them. We, hematologists and technicians, must be well prepared to report our own observation of an un-explained morphological abnormality.

Normal bone marrow function over 6 years in a patient with dysplastic hematopoiesis and a complex karyotype

Myelodysplasia associated with a complex karyotype is usually associated with advanced stage myelodysplastic syndrome (MDS) and an enhanced risk to develop secondary leukemia. We report on a 36-year-old female patient who was first presented in 1997 because of 'Pseudo Pelger-Huet' neutrophils. The remaining blood and differential counts were normal. Bone marrow examination revealed dysplasia in the erythroid and granulocytic series, no increase in blasts, and a karyotype with complex aberrations involving chromosomes 7, 13, 20 and 22. Almost all metaphases examined appeared to be affected. During the next few months, the patient was closely monitored and considered as candidate for bone marrow transplantation. However, blood counts remained stable without occurrence of significant cytopenias or an increase in blasts. Re-examinations of the bone marrow in 1998 and 1999 disclosed identical results compared to that obtained in 1997. After a total follow up of 6 years, the patient is still in good health with normal blood counts and persisting 'Pseudo Pelger-Huet' neutrophils. This exceptional case supports the notion that complex chromosomes are not invariably associated with rapid disease evolution in MDS.

Role of nuclear lamins in nuclear segmentation of human neutrophils

Nuclear breakdown leading to the formation of apoptotic bodies has been postulated to involve degradation of nuclear structural proteins, such as lamins A/C and B. Although nuclear segmentation occurs during the maturation of polymorphonuclear leukocytes (neutrophils), its mechanism is not known. We found that human neutrophils have lamin B but lack lamins A/C while mononuclear cells possess all three types of lamin as assessed by immunoblotting. Differentiation of human promyelocytic HL-60 cells into neutrophil-like cells was also accompanied by the down-regulation of lamins A/C but not of lamin B. Moreover, when compared with normal cells, neutrophils with the Pelger-Huët anomaly of nuclear hyposegmentation exhibited significantly lower activity of caspase-6, a lamin A/C-cleaving enzyme. Differentiated HL-60 cells showed higher activity of caspase-6 than that of untreated cells. These observations allow us to speculate that remodeling of nuclear lamins might underlie the mechanism for nuclear segmentation of neutrophils.

Granulocytes with segmented nucleus retain normal chromosomes 17 in Philadelphia chromosome-positive chronic myeloid leukemia with i(17q) and pseudo-Pelger anomaly. A case report studied with fluorescence in situ hybridization

Previous reports suggested a correlation between the deletion of the terminal region of the short arm of a chromosome 17 and the appearance of dysgranulopoiesis in myeloproliferative disorders. Using the dual-color fluorescence in situ hybridization technique we analyzed the bone marrow and peripheral blood cells of a Philadelphia chromosome-positive chronic myeloid leukemia (CML) patient showing at the onset of transformation into blastic crisis both metaphases with the i(17q) as well as granulocytes without nuclear segmentation. This phenomenon is defined as pseudo-Pelger-Huët anomaly. Using two probes, one specific for 17p and one for 17q, we determined the presence or absence of the i(17q) in both metaphase and interphase cells. Moreover, we observed that all cells with a polysegmented nucleus typical of mature granulocytes did not have i(17q) but had two normal chromosomes 17. This observation confirmed the correlation between 17p deletion and the appearance of pseudo-Pelger anomaly. This finding may also be useful from a clinical point of view: the appearance of pseudo-Pelger cells in CML indicates that 17p deletion actually occurred. This event implies a negative prognosis.

Familial Pelger-Huet anomaly accompanied by tuberculosis and complicated by acute polyarthritis

A patient with familial Pelger-Huet (PH) anomaly, which accompanied tuberculosis, and acute polyarthritis is described. Investigations surrounding this case suggests that the immunological abnormalities may be associated with the PH anomaly and the tuberculosis, and that the complications may be related to the development of the acute polyarthritis.

Hematologic manifestations of long-term valproate therapy

Sixty patients receiving long-term valproate (VPA) monotherapy were studied for hematologic side effects. All were patients in a long-term care facility and ranged in age from 2 to 29 years (mean 14.6 years). Twenty developed at least one prominent hematologic abnormality. Thrombocytopenia and macrocytosis were the most common findings. In patients with macrocytosis, platelet counts were inversely related to VPA levels. Serum B12 levels were increased in 51 of the patients. In 12 patients with macrocytosis who were extensively studied, no etiology for the increased MCV could be identified. An increased number of Pelger-Huet-like cells was noted in these 12 patients. None of the patients demonstrated hepatic dysfunction. Hematologic toxicity was never severe enough to discontinue therapy and always responded to small decrements in VPA therapy. VPA was discontinued in only 1 patient, owing to poor seizure control.

Pelger-Huët anomaly mimicking 'shift to the left'

A case report is presented of an 83-year-old male patient with respiratory distress, body temperature of 38.5 degrees C, bilateral white infiltrates on chest X-ray and ECG showing acute myocardial infarction. Clinical evaluation led to the suspicion of severe infection accompanying lung congestion due to the infarction, mostly because his white blood cell differential count showed a persistent severe 'shift to the left'. Re-examination of his blood smear showed that the 'shift to the left' did not consist of band forms but of a 'Pelger-Huet' anomaly of the granulocytes. Recognition of this anomaly in the light of rapid clinical and radiological improvement precluded the administration of antibiotics for the diagnosis of severe infection with pulmonary involvement, which responded to diuretic therapy alone.

Pelgeroid-like anomalous cells in the diagnosis of neutrophilic dermatosis associated with myelodysplastic syndrome

Neutrophilic dermatoses (ND), with or without accompanying myelodysplastic syndrome (MDS), were examined in terms of nuclear abnormality like pelgeroid anomaly of infiltrating cells into skin lesions. Six ND accompanying MDS showed 1.0 to 13.5% of such anomalous cells among infiltrating cells. In contrast, ND without accompanying myeloproliferative disorders rarely had such anomalous cells. Our findings suggest that pelgeroid-like anomalous cells infiltrating into ND are probably a good marker of underlying MDS.

[Myelodysplastic syndrome in a patient with familial Pelger-Huet anomaly]

This paper reports on a patients with congenital Pelger-Huet anomaly who developed myelodysplastic syndrome (MDS). A 45-year-old female was referred for investigation of pancytopenia of 6 months' duration. Hereditary Pelger-Huet anomaly was diagnosed by family study 7 years prior to admission. On admission, Hb was 6.5 g/dl, Ht 19.9%, Platelets 1.8 x 10(4)/microliters, and WBC 1,200/microliters with 2% myelocytes, 9% metamyelocytes, 14% bands, 2% segmented neutrophils, 58% lymphocytes and 5% monocytes. Most of the granulocytes were Pelger-Huet type with strikingly clumped nuclear chromatin. Bone marrow aspirate demonstrated 3.6% blasts and dysplastic changes including megaloblastoid features in erythroid series and micro-megakaryocytes compatible with refractory anemia, a subtype of MDS. The association of hereditary Pelger-Huet anomaly and MDS is discussed.

Effects of G-CSF, GM-CSF, and IL-5 on nuclear segmentation of neutrophils and eosinophils in congenital or acquired Pelger-Huët anomaly

We studied the in vitro effects of granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin 5 (IL-5) on nuclear segmentation of neutrophils and eosinophils from three patients with congenital or acquired Pelger-Huët anomaly. After a 24-h incubation with G-CSF, the majority of neutrophils showed nuclear development characterized by a bilobed appearance. In contrast to neutrophils, the nuclear segmentation of eosinophils was not induced after incubation with G-CSF, GM-CSF, or IL-5. These results suggest that G-CSF plays some role in the nuclear development of neutrophils, whereas IL-5 may not have such an effect on eosinophil maturation in the individual cases studied.

[The Pelger-Huët anomaly. A clinical and ultrastructural study of a family from northeastern Mexico]

The Pelger-Huet anomaly is a benign disorder which affects the morphology of the granulocytes and is namely inherited as an autosomic dominant trait. The frequency of this anomaly varies from country to country and in México this constitutes the sixth family reported. This is a case of a 21-month-old boy whose anomaly was detected during the study of his ferropenic anemia with which he arrived at the hospital. During the study of his nine family members, the anomaly was found to have also been present in his father. An electron microscopy study of the subject, his father's and a normal control's neutrophils was conducted. The patient's and his father's leucocyte granules were found to be normal but decreased in number. This work includes some discussion on inherited traits, their presentation, morphology, differential diagnosis and emphasizes the importance in recognizing this anomaly and the promotion of genetic counselling.

Leukocyte function in Pelger-Huët anomaly of dogs

Leukocyte function was evaluated in five dogs with Pelger-Huët (P-H) anomaly and in five control dogs. No significant differences were found between groups in neutrophil adherence, random movement, chemotaxis, phagocytosis, or bacterial killing of Staphylococcus intermedius. Neutrophils migrated rapidly into inflammatory sites where progressive nuclear lobulation was noted over time. Antibody titers to exogenous antigens were similar in the P-H and control groups indicating B- and T-lymphocyte cooperation in humoral immunity. Lymphocyte blastogenesis to phytohemagglutinin also was similar in both groups suggesting the presence of a responsive T-lymphocyte population. These findings indicate that no apparent predisposition to infection or immunodeficiency exists in dogs with P-H anomaly.

Congenital Pelger-Huet anomaly in triplets

Congenital Pelger-Huet anomaly is an autosomal dominant disorder characterized by incomplete nuclear segmentation of granulocytes. The morphology of these mature but hyposegmented granulocytes may be confused with that of immature granulocytes (bands), thereby suggesting bacterial infection. We report the first known case of triplets with this condition, and emphasize the need to identify accurately this normal variant.

Acquired Pelger-Huet anomaly in a case of non-Hodgkin's lymphoma

Acquired Pelger-Huet anomaly has been found in association with both hematologic and nonhematologic diseases. While its association with myeloid hematologic disorders is well known, this granulocytic anomaly has also been found in chronic lymphocytic leukemia, multiple myeloma and Hodgkin's disease. This report describes a case of acquired Pelger-Huet anomaly in non-Hodgkin's lymphoma and reviews the association of this anomaly with both lymphoid and myeloid hematologic disorders.

Nuclear segmentation, ultrastructure, and cytochemistry of blood cells from dogs with Pelger-Huët anomaly

Nuclear segmentation, ultrastructural features and cytochemical staining reactions of blood cells from 7 dogs with the heterozygous form of Pelger-Huët (P-H) anomaly were investigated. Significant nuclear hyposegmentation of granulocytes, monocytes and megakaryocytes was found, indicating a common stem cell defect in the nuclear segmentation or lobulation process. Neutrophils and eosinophils from female P-H dogs lacked sex chromatin drumsticks. Other than the suggestion of nuclear hyposegmentation and the presence of coarse heterochromatin, no ultrastructural abnormalities were discerned. Cytochemical staining by a-naphthyl acetate esterase, alkaline phosphatase, naphthol ASD chloroacetate esterase, periodic acid-Schiff, peroxidase and Sudan black B techniques gave similar results for P-H and control dog leukocytes and platelets.

Acquired Pelger-Huet anomaly associated with Mycoplasma pneumoniae pneumonia

A case report of a healthy 33-year-old man with Mycoplasma pneumoniae pneumonia who concomitantly had the acquired Pelger-Huet anomaly develop is presented. Up to 31% of his total white blood cell count was comprised of Pelger-Huet cells at the height of his clinical illness. The Pelger-Huet cell count returned to 0% after doxycycline therapy and resolution of the pneumonia. No other explanation for the Pelger-Huet anomaly could be determined. A review of the pertinent hematologic literature is included.

Pelger-Huët anomaly in cats

Pelger-Huët anomaly was diagnosed in a young male cat on the basis of persistent nuclear hyposegmentation of blood granulocytes, absence of clinical disease or feline leukemia virus infection, and demonstration of genetic transmission of the anomaly. Neutrophils, eosinophils, basophils, and monocytes had significantly less nuclear segmentation when compared to similar leukocyte types from a control cat. On smears of bone marrow, megakaryocytes also appeared hyposegmented. A test mating with an unaffected queen produced a litter of five kittens (three males, two females). One male and one female kitten had the Pelger-Huët trait on examination of blood smears. Autosomal dominant transmission of this anomaly is suspected based on these findings.

Pelger-Huet anomaly of granulocytes in a patient with tuberculosis

The association of abnormal granulocyte nuclear formation and tuberculosis was first reported by Pelger in 1928. Huet, however, concluded this defect was hereditary, and the association of Pelger-Huet anomaly (PHA) of granulocytes and tuberculosis was obscured for many years. We report the second patient in the English literature with severe tuberculous infection and PHA, further substantiating the diagnostic and prognostic importance of PHA and tuberculosis.

Cytogenetic and functional studies of leukocytes with Pelger-Huët anomaly

A cytogenetic study was undertaken in 15 cases of Pelger-Huët (P-H) anomaly in 3 families. An enlarged short arm of chromosome 22 (22p+) was found in 14 cases, but in these families 4 cases without P-H anomaly did not show 22p+ in the karyotype. In P-H anomaly, delayed skin hypersensitivity reactions, levels of serum IgG, IgM and IgA, lymphocyte subpopulations, and natural killer and antibody-dependent, cell-mediated cytotoxicity activities were within normal range. The level of serum IgE, mitogen responses in peripheral blood lymphocyte and plaque-forming cell counts were also within normal range with the exception of a case with atopic eczema. Enzymatic activities, nitroblue tetrazolium reduction and phagocytic capacities of neutrophils appeared normal. Abnormalities of neutrophils in cases of P-H anomaly, as compared with normal subjects, were also negative in examinations for chemotaxis and spontaneous migration under agarose and in a membrane filter.

Neutrophilic movement of a Basenji with Pelger-Huët anomaly

Random and chemotactic neutrophilic movements in a Basenji with Pelger-Huët (P-H) anomaly was compared with such movement in 5 healthy control dogs. Duplicate samples of neutrophils were quantitated after 5, 10, 15, 30, and 45 minutes of incubation. On the basis of population mean responses, no significant difference (P greater than 0.05) was found between P-H and control neutrophils for any type of movement at any time interval examined. These findings indicate that the movement of neutrophils with P-H anomaly may be unaffected by the nuclear abnormality.

Pseudo-Pelger-Huët anomaly in chronic lymphocytic leukemia

Anomalous cells of the Pelger-Huët type appear mainly in diseases affecting granulopoiesis such as myeloproliferative disorders, aplastic anemia and agranulocytosis [1]. The association of this anomaly with disorders of the lymphatic system is rare and had been described only in 1 patient with chronic lymphocytic leukemia [2]. Recently we have encountered another patient with chronic lymphocytic leukemia and acquired Pelger-Huët anomaly.

Homozygous form of the Pelger-Huët leukocyte anomaly in man

A report on a new case of Pelger-Huët (PH) leukocyte anomaly in the homozygous form in an 18-month-old girl is presented. Clinically, the proband shows no special symptoms dependent on the leukocyte anomaly, but polydactyly affects both hands (six fingers on one hand) and feet (six toes on both feet). Her pedigree reveals the existence of three couples in which both husband and wife are heterozygous carriers of the PH anomaly. Study of the family lineage suggests that transmission of the leukocyte anomaly is prevailingly dominant in nature with complete penetration and variable expression.

[The Pelger-Huët leukocyte nuclear anomaly: a morphologic, cytochemical, cytogenetic and ultrastructural study of 39 cases (authors' transl)]

Thirtynine of nuclear leukocyte Pelger-Huët anomaly occurring in two Italian families are presented and discussed. The study of the genealogical trees has confirmed that the anomaly is a familial and congenital form, with autosomal dominant inheritance. The incidence of the anomaly in our popolation is 1 to 4,500. In the heterozygous form the anomaly is characterized by decreased segmentation of the nucleus, distinctive nuclear forms and pyknosis of the nuclear chromatin out of proportion of the nuclear area. The results of morphologic, cytochemical, ultrastructural and cytogenetic studies are reported.

Congenital disorders of the function of polymorphonuclear neutrophils

This review has concentrated on clinical syndromes for which a congenital basis of polymorphonuclear neutrophil dysfunction has been identified. The first clinical syndrome found to be associated with dysfunctional polymorphs was chronic granulomatous disease of childhood. Identification of a cellular defect in oxidative metabolism and microbicidal activity of polymorphonuclear neutrophils from patients with CGD stimulated intense investigation of the function of phagocytes in several clinical entities characterized by increased susceptibility to infection. Other diseases with a probable congenital basis for polymorph dysfunction include Chediak-Higashi syndrome, myeloperoxidase deficiency, severe glucose-6-phosphate dehydrogenase deficiency, and Down's syndrome. Functional defects have also been identified in neutrophils with morphologic abnormalities, such as the Pelger-Huet anomaly and the May-Hegglin anomaly, and in neutrophils without alkaline phosphatase or with a disorder of the glutathione system. The evidence for a relation between these cellular disorders and susceptibility to infection is tentative. Patients with congenital disorders of polymorphonuclear neutrophil microbicidal function frequently suffer prolonged infections in spite of appropriate antimicrobial therapy, and severe lesions recur with discouraging frequency. These lesions are usually soft tissue or bone abscesses, and the etiologic agents are typically staphylococci, gram-negative enteric species, or fungi. The infectious disease problems of patients with phagocytic cell disorders are usually quite distinct from the problems of patients without immunoglobulins or with complement deficiency. Patients with agammaglobulinemia, for example, suffer recurrent septicemia or meningitis due to Streptococcus pneumonia or H. influenzae. Septicemia, especially with the pyogenic bacterial species, is unusual in patients with polymorphoinuclear dysfunction. A major contribution of the currently intense investigation of cells from patients with congenital disorders of phagocyte function has been the greatly increased understanding of the molecular events necessary for the normal function of these cells. The role of the oxidative metabolic burst during phagocytosis has been clearly identified as essential to the microbicidal function of polymorphs and monocytes, and the glutathione system has been identified as essential to the regulation of these oxidative reactions. It is anticipated that these studies may lead to practical methods for "stimulating the phagocytes" in patients with increased susceptibility to infection.

Acquired hyposegmentation of granulocytes (pseudo-Pelger-Huët anomaly) in a dog

Hyposegmentation of granulocyte nuclei was diagnosed in an adult dog after unsuccessful attempt at finding an occult chronic infection. Intermittent signs of prostatitis were temporarily observed, but the immature nature of circulating granulocytes persisted nine months. Electron microscopic examination and neutrophil function studies revealed no abnormalities. Since previous blood smear evaluation had been normal, it is proposed that the granulocyte anomaly was acquired and may have resulted from an idiosyncratic reaction to one of several chemotherapeutic agents administered.

Studies of the Pelger-Huët anomaly in foxhounds

An inbred family of foxhounds with four members expressing the Pelger-Huët (P-H) anomaly is described. The disease-free status of all P-H affected dogs suggests a benign disorder, although review of breeding records indicated a lower percentage of pups weaned (63%) by P-H females compared with the percentage of pups weaned (81%) by outcrossed females throughout the foxhound colony. Light-microscopic examination of blood films from affected dogs revealed 50--67% neutrophils with round, oval, or bean-shaped nuclei and rarely (0.5%) segmented nuclei. Neutrophils examined by electron microscopy showed the nuclei to have a fine nuclear cleft and condensed chromatin and the cytoplasm to have mature heterochromatic granulation. Local P-H neutrophil mobilization through a standard skin abrasion into a chamber containing autologous serum was impaired at all time periods evaluated (1, 4, 8, and 24 hours) compared with the neutrophil mobilization by normal dogs. Antibody response to sheep erythrocyte immunization was also impaired. In vitro reactivity of normal and P-H lymphocytes stimulated by pokeweed mitogen was depressed when lymphocytes were cultured in plasma from a P-H dog but not when cultured in plasma from a normal dog. Vigorous blastogenic responses to phytohemagglutinin by normal and P-H lymphocytes cultured in P-H or normal plasma suggest the presence of a factor(s) in the P-H plasma which interferes with B-lymphocyte reactivity.

Eosinophilic acquired Pelger-Huët anomaly in acute myeloblastic leukemia. A cytochemical study

Decreased nuclear segmentation and coarse chromatin only in mature eosinophils was seen in a patient with acute myeloblastic leukemia. These eosinophils were considered to have acquired Pelger-Huët anomaly. On cytochemical study they displayed a strong PAS-positive reaction.

[Case of Pelger-Huet anomaly in its exceptional homozygotic variant]

After briefly recalling the cytomorphological aspects of Pelger-Huet anomaly, its statistical occurrence, the modalities of hereditary transmission and its differentiation from pseudo-Pelger, a case of the homozygotic variant is reported. The practical and theoretical importance of the anomaly is commented on briefly.

Ultrastructural features of the blood cells in a patient with Pelger-Huët anomaly

A case of congenital Pelger-Hüet anomaly of the peripheral blood cells is described. Electronmicroscopic examination of the blood cells revealed nuclear bridges and appendices in the polymorphonuclear leukocytes. The number of cytoplasmic granules was diminished, but the size of the secondary granules was markedly increased. The eosinophils showed pronounced polymorphism of the granules, and the platelets showed a decrease in the alpha-granulomere number.

[Constitutional familial leucocytopenia with partial Pelger anomaly and delayed development of bone (author's transl)]

The clinical and hematological findings in 4 boys of a family with a chronic constitutional leukocytopenia are described. Possible X-chromosomal sex-linked genetic transmission, the benign clinical course as well as the association with clinical and cytological hints of the involvement of the lymphatic cellular immunological system suggest a disease of its own. It was classified as a mild form of myelolymphatic insufficiency similar to reticular dysgenesis. The significance of Pelger-Huët anomalies of neutrophils demonstrated in the blood of the mother and of Pelger-like forms in the blood of children are discussed.