Common Blood Test Indices for Predicting Transient Abnormal Myelopoiesis-Related Mortality in Infants with Down Syndrome

Transient abnormal myelopoiesis (TAM) can cause early death in children with Down syndrome, and liver failure is the most common cause of death. The aim of this single-center retrospective study was to identify a quantitative index for predicting TAM-related mortality at the time of diagnosis. Of the 462 children with Down syndrome admitted to our hospital from 1992 to 2021, we studied 12 infants with TAM-related death and 31 survivors who were diagnosed with TAM. In the death and survival groups, the median gestational ages were 34.9 and 37.1 weeks, respectively (p = 0.12). At diagnosis, the white blood cell (WBC) counts were 99.2 and 36.2 × 109/L (p = 0.011), the hemoglobin concentrations were 131 and 159 g/L (p = 0.009), and the serum albumin concentrations were 23 and 31 g/L (p < 0.001), respectively. The areas under the receiver operating characteristic curve for the abilities of the WBC count, hemoglobin, and serum albumin at diagnosis to predict survival were 0.75, 0.76, and 0.85, respectively. The serum albumin concentration threshold of 28 g/L at diagnosis had sensitivity of 0.79 and specificity of 0.82. Gestational age and serum albumin concentration were entered into a logistic regression model. The serum albumin concentration was an independent indicator of TAM-related death (adjusted odds ratio, 0.78; 95% confidence interval, 0.65-0.93; p = 0.005). In conclusion, a low serum albumin concentration at diagnosis may be a good predictor of TAM-related death.

Myeloid Proliferations Associated with Down Syndrome: Clinicopathologic Characteristics of Forty Cases from Five Large Academic Institutions

INTRODUCTION

The incidence of myelodysplastic syndrome and acute myeloid leukemia is significantly increased in children with Down syndrome (DS). Within the revised 2016 WHO edition, these entities are jointly classified as myeloid leukemia associated with DS (ML-DS). Additionally, infants with DS may develop transient abnormal myelopoiesis (TAM) which is histomorphologically similar to ML-DS. While TAM is self-limiting, it is associated with an increased risk of subsequently developing ML-DS. Differentiating TAM and ML-DS is challenging but clinically critical.

METHODS

We performed a retrospective review of ML-DS and TAM cases collected from five large academic institutions in the USA. We assessed clinical, pathological, immunophenotypical, and molecular features to identify differentiating criteria.

RESULTS

Forty cases were identified: 28 ML-DS and 12 TAM. Several features were diagnostically distinct, including younger age in TAM (p < 0.05), as well as presentation with clinically significant anemia and thrombocytopenia in ML-DS (p < 0.001). Dyserythropoiesis was unique to ML-DS, as well as structural cytogenetic abnormalities aside from the constitutional trisomy 21. Immunophenotypic characteristics of TAM and ML-DS were indistinguishable, including the aberrant expression of CD7 and CD56 by the myeloid blasts.

DISCUSSION

The findings of the study confirm marked biological similarities between TAM and ML-DS. At the same time, several significant clinical, morphological, and genetic differences were observed between TAM and ML-DS. The clinical approach and the differential diagnosis between these entities are discussed in detail.

A rare case of hepatic sinusoidal occlusive syndrome in a premature neonate with trisomy 21

Trisomy 21 (Down Syndrome) may lead to multiple hematological and hepatobiliary manifestations including the development of transient abnormal myelopoiesis. While many cases resolve, transient abnormal myelopoiesis may lead to significant morbidity and mortality in a small percentage of patients. This condition may present a diagnostic challenge for physicians and currently there is only limited data on effective treatments, particularly with low blast percent transient abnormal myelopoiesis. We present a case of a neonate with trisomy 21 and multiple congenital anomalies who consequently developed hepatic failure with evidence of non-cirrhotic portal hypertension likely due to transient abnormal myelopoiesis. This clinical scenario highlights the need for additional evaluation for transient abnormal myelopoiesis associated hepatic disorder and possibly hepatic sinusoidal occlusive syndrome among trisomy 21 neonates particularly with low blast percentage.

Epithelioid Inflammatory Myofibroblastic Sarcoma with Leukemoid Reaction

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare and aggressive inflammatory myofibroblastic tumour (IMT) variant. This report identifies the first case of EIMS with leukemoid reaction. This is also the first case in which pancreatic infiltration occurred from the disease onset. A 14-year male patient presented with an 18×18×10 cm mass at the retroperitoneal space and a white blood cell (WBC) count of 85×109/L. The mass and the invaded tissues were surgically removed with tumour-free margins. Histopathology and bone marrow aspiration confirmed the diagnosis of EIMS with leukemoid reaction. The tumour recurred with hepatic and pulmonary metastasis one month after the surgery. WBC count also increased progressively with the tumour recurrence. There is no consensus on the treatment of EIMS. Since ALK rearrangement presents in all the EIMS cases, surgical resection combined with crizotinib or other targeted drugs may improve the prognosis. Key Words: Sarcoma, Soft tissue neoplasms, Leukemoid reaction, Crizotinib.

"TAM"ing of the shrew-challenges in the diagnosis of Neonatal leukemia with Down's syndrome -A case report with literature review

The latest WHO (2017) classification describes the hematological abnormalities of Down's syndrome as a separate entity under 'Myeloid proliferations associated with Down's syndrome'. It includes Transient Abnormal Myelopoiesis and Myeloid leukemia of Down's syndrome. Here we report a case of a 3 days old neonate with Down's syndrome, presenting with a leukemic blood picture. The baby had icterus, fever and hepatosplenomagaly. Peripheral blood showed megakaryoblasts and giant platelets. A diagnosis of transient abnormal myelopoiesis was made by confirming with karyotyping and immunophenotyping. We attempt to address all the diagnostic challenges faced by a clinician and pathologist same, upon encountering such a case,by following an algorithmic approach. The mandatory need for follow up and cytogenetic studies in identifying high risk cases that will become myeloid leukemia of Down's syndrome are stressed. Our case also throws light upon the significance of identification of GATA1 mutation in diagnosing and prognostication of such cases.

Mechanisms of Progression of Myeloid Preleukemia to Transformed Myeloid Leukemia in Children with Down Syndrome

Myeloid leukemia in Down syndrome (ML-DS) clonally evolves from transient abnormal myelopoiesis (TAM), a preleukemic condition in DS newborns. To define mechanisms of leukemic transformation, we combined exome and targeted resequencing of 111 TAM and 141 ML-DS samples with functional analyses. TAM requires trisomy 21 and truncating mutations in GATA1; additional TAM variants are usually not pathogenic. By contrast, in ML-DS, clonal and subclonal variants are functionally required. We identified a recurrent and oncogenic hotspot gain-of-function mutation in myeloid cytokine receptor CSF2RB. By a multiplex CRISPR/Cas9 screen in an in vivo murine TAM model, we tested loss-of-function of 22 recurrently mutated ML-DS genes. Loss of 18 different genes produced leukemias that phenotypically, genetically, and transcriptionally mirrored ML-DS.

Isolated thrombocytopenia in childhood: what if it is not immune thrombocytopenia?

INTRODUCTION

Childhood immune thrombocytopenia (ITP) remains a diagnosis of exclusion when isolated thrombocytopenia is not part of another disease process. In practice, the diagnosis of ITP can only be confirmed when thrombocytopenia resolves or is excluded after the recognition of a primary cause.

METHODS

The records of 87 consecutive children with isolated thrombocytopenia seen over a nine-year period in a private paediatric haematology practice were reviewed retrospectively. Children in whom a primary cause was eventually found were the subjects of a further descriptive study.

RESULTS

9 (10%) children with isolated thrombocytopenia were not diagnosed with ITP because a primary disease was found. Of these nine cases, four had thrombocytopenia recognised during the neonatal period, consisting of perinatal cytomegalovirus infection (n = 2), meconium aspiration pneumonia (n = 1) and transient abnormal myelopoiesis associated with Down syndrome (n = 1). The remaining five children were each found to have familial thrombocytopenia, portal hypertension, cutaneous mastocytosis, May-Hegglin anomaly and systemic lupus erythematosus. Two of them had a history of failure of response to corticosteroid therapy.

CONCLUSION

Secondary thrombocytopenia is not uncommon in a tertiary paediatric specialty practice with adequate evaluation. Thrombocytopenia occurring during the newborn period and failure of steroid therapy are predictive of secondary cases.

Loss of Full-Length GATA1 Expression in Megakaryocytes Is a Sensitive and Specific Immunohistochemical Marker for the Diagnosis of Myeloid Proliferative Disorder Related to Down Syndrome

OBJECTIVES

Myeloid proliferative disorders associated with Down syndrome (MPD-DS), including transient abnormal myelopoiesis and myeloid leukemia associated with Down syndrome (DS), harbor mutations of GATA1, a transcription factor essential for erythroid and megakaryocytic development. These mutations result in a N-terminally truncated GATA1 (GATA1s) and prohibit the production of the full-length GATA1 (GATA1f). Here, we demonstrate the utility of immunohistochemical GATA1f reactivity in diagnosing MPD-DS.

METHODS

Immunohistochemical studies for GATA1f expression were performed on bone marrow biopsy specimens.

RESULTS

In all cases of MPD-DS, megakaryocytes lacked GATA1f expression. In contrast, GATA1f expression was detected in megakaryocytes in all specimen types from patients without DS (normal bone marrows, pediatric myelodysplastic syndrome, juvenile myelomonocytic leukemia, adult acute megakaryocytic leukemia [pediatric and adult; without trisomy 2]), as well as normal bone marrows from patients with DS.

CONCLUSIONS

The lack of GATA1f expression is a sensitive and specific immunohistochemical marker for MPD-DS.

Down Syndrome with Patent Ductus Venosus and Hepato-Biliary-Pancreatic Abnormalities

The association between Down syndrome and congenital portosystemic shunts, most commonly caused by patent ductus venosus, remains relatively unknown. The authors present a girl with Down syndrome with patent ductus venosus, pancreaticobiliary maljunction and paucity of interlobular bile ducts, presenting with neonatal cholestasis and transient abnormal myeloproliferative disorder. To the best of authors' knowledge, no report of the concurrent presence of the above in Down syndrome has been published.

A neonate with a vesiculopustular rash

Transient myeloproliferative disorder (TMD) is a unique form of acute megakaryocytic leukemia (AMKL) that spontaneously regresses and is found in 3% to 10% of neonates with Down syndrome (DS). We report the case of a neonate with DS who presented with a widespread vesiculopustular eruption as an initial sign of TMD. Complete blood count was normal but peripheral smear revealed circulating megakaryoblasts. The severity of skin lesions correlated with the blast count. By age 2 months the TMD resolved and the patient remains disease-free after 18 months of follow-up. Several important features of TMD are highlighted: skin findings may provide an important clinical clue to TMD diagnosis; manual review of the peripheral smear is necessary when TMD is suspected; and patients with a history of TMD have a very high (∼30%) risk of recurrence with a persistent AMKL within the first 3 years of life.

Transient leukemia in a newborn without Down syndrome: case report and review of the literature

Transient neonatal leukemia occurs almost exclusively in Down syndrome babies. We report here the unusual case of a newborn without Down syndrome who presented neonatal transient leukemia and who achieved spontaneously complete remission. Trisomy 21 and GATA1 mutation were both present in leukemic cells. While close follow-up is advised since true leukemia may develop later, the patient is still in remission for 2.5 years. We performed a literature review of 15 other similar cases.

CONCLUSION

Our case of transient leukemia without Down syndrome and the literature review highlight the important role of trisomy 21 and GATA1 mutation in the development of transient neonatal leukemia.

Leukemoid reaction associated with pediatric nasopharyngeal carcinoma: An unusual presentation

Nasopharyngeal carcinoma is a tumor originating from the surface epithelial cells of nasopharynx. It is rare in children and adolescents. Most common physical finding is a neck mass. Most children with nasopharyngeal carcinoma present with advanced stage disease. The presentation with hematological abnormalities in patients without systemic metastasis is extremely rare. We reported a 14-year-old boy presenting with a mass at the right side of the pharynx and leukemoid reaction. To our knowledge, this is the first report of leukemoid reaction associated with pediatric nasopharyngeal carcinoma in English literature.

Leukemoid reaction, a rare manifestation of autoimmune hemolytic anemia in a case of small duct primary sclerosing cholangitis

A 48 year old lady presented with jaundice and exertional breathlesness. Her laboratory reports showed anaemia, reticulocytosis, leucocytosis, elevated Lactate Dehydrogenase (LDH), alkaline phosphatase levels, hyperbillirubinemia and positive direct Coomb's test. After ruling out all the other causes of autoimmunity and hemolytic anemia, she was diagnosed as leukemoid reaction due to autoimmune hemolytic anemia with primary sclerosing cholangitis. Patient showed immediate improvement after corticosteroids.

Leukemoid reaction in malignant bone tumor patients - a retrospective, single-institution study

BACKGROUND

To the Authors' knowledge, the literature regarding leukemoid reaction in patients with malignant bone tumor is sparse, and most of patients with leukemoid reaction have poor prognosis.

AIM

To study the leukemoid reaction in malignant bone tumor patients.

MATERIALS AND METHODS

A total of 105 consecutive malignant bone tumor patients with a white blood cell count > 50,000/microL were retrospectively identified over a 4-years period (2007-2010). Those patients without a secondary cause of their leukocytosis were defined as having a paraneoplastic leukemoid reaction.

RESULTS

Three etiologies of the leukocytosis were found in those 105 patients: the major one was paraneoplastic leukemoid reaction which accounted for 56%; the second one was hematopoietic growth factors defect accounting for 30%; 14% patients were caused by infection and Tumor bone marrow involvement. The patients diagnosed with a paraneoplastic leukemoid reaction typically had neutrophil predominance (94.8%) and radiographic evidence of metastatic diseases (78%). They were clinically stable, but had a poor prognosis. 95% either died or were discharged to hospice within 12 weeks of their initial extreme leukocyte count. Both of the 2 (2%) patients who survived over 12 weeks received effective antineoplastic therapy.

CONCLUSIONS

Patients with typical paraneoplastic leukemoid reaction were clinically stable despite having large tumor burdens. However, clinical outcomes were poor unless receiving an effective antineoplastic treatment.

Understanding and recognizing the Pelger-Huët anomaly

The Pelger-Huët anomaly (PHA) is a recognized morphologic variant affecting all granulocytes but is most evident in polymorphonuclear neutrophils (PMNs). PHA is caused by a decreased amount of the lamin B receptor (LBR). Recognition of PHA morphologic features serves as a marker for mutations in the LBR gene. This review summarizes the history of PHA and the current knowledge of the functions of the LBR. Guidance is given for distinguishing PHA from other hematologic disorders in which granulocytes may show similar changes. Recognition of PHA in the laboratory should prompt communication to the patient's physician about the possible clinical significance of this finding and the recommended screening for the anomaly in other family members by CBC and review of a peripheral blood smear.

Etiology and outcome of extreme leukocytosis in 758 nonhematologic cancer patients: a retrospective, single-institution study

BACKGROUND

To the authors' knowledge, the literature regarding extreme leukocytosis in solid tumor patients is sparse, consisting of a few case reports and small case series.

METHODS

A total of 3770 consecutive solid tumor patients with a white blood cell count>40,000/microL were retrospectively identified over a 3-year period (2005-2008). Those patients without a secondary cause of their leukocytosis were defined as having a paraneoplastic leukemoid reaction.

RESULTS

A total of 758 (20%) patients with solid tumors and extreme leukocytosis were identified. The etiology of the leukocytosis was hematopoietic growth factors in 522 (69%) patients, infection in 112 (15%) patients, high-dose corticosteroids in 38 (5%) patients, newly diagnosed leukemia in 9 (1%) patients, and paraneoplastic leukemoid reaction in 77 (10%) patients. The patients diagnosed with a paraneoplastic leukemoid reaction typically had neutrophil predominance (96%) and radiographic evidence of metastatic disease (78%), were clinically stable, and had a poor prognosis; 78% either died or were discharged to hospice within 12 weeks of their initial extreme leukocyte count. All of the 8 (10%) patients who survived>1 year received effective antineoplastic therapy.

CONCLUSIONS

Infection was an uncommon cause of extreme leukocytosis in patients with solid tumors. Patients with paraneoplastic leukemoid reactions typically were clinically stable despite having large tumor burdens. However, clinical outcomes were poor unless effective antineoplastic treatment was received.

Differential diagnosis issues in a case of gastric carcinoma associated with leukemoid reaction

Gastric tumors share many characteristics, making a definitive diagnosis challenging. Gastric adenocarcinomas represent 90% of malignant stomach tumors, meanwhile the frequency of gastric lymphoma range between 1-5% of all gastric cancers. Gastric carcinoma bears resemblance with particular forms of non-Hodgkin's lymphoma of the stomach, not only in morphological presentation, but also in clinical configuration and laboratory tests. We report a case of gastric carcinoma with abnormal hematological picture dominated by leukemoid reaction and peculiar histopathological aspect. Pleomorphism of neoplastic cells and distinct arrangement of these give rise to the need of differentiation between a carcinoma and a non-Hodgkin's lymphoma of the stomach. On immnohistochemical grounds, we succeeded in our action of segregation between the two lesional entities and we establish as definitive diagnosis that of poorly differentiated gastric adenocarcinoma. Additionally, leukemoid reaction proved to be a manifestation of a bone marrow metastasis from gastric cancer.

Hepatocellular carcinoma presenting as neutrophilic leukaemoid reaction--a rare entity

Leukaemoid reaction is a rare, growth factor-driven, paraneoplastic manifestation of hepatocellular carcinoma. It may masquerade as the neutrophilic chronic myeloid leukaemia or as chronic neutrophilic leukaemia. A 52-year-old male presented with hepatosplenomegaly and severe leucocytosis. He had progressive leucocytosis, neutrophil alkaline phosphatase score elevated, liver function tests altered. FNAC from the mass in the liver revealed features of moderately differentiated hepatocellular carcinoma. The patient deteriorated within two weeks and died thereafter.

In vitro cell growth stimulated by recombinant human cytokines can help to diagnose transient leukemia in neonates

BACKGROUND/PURPOSE

In a previous study, we demonstrated that in vitro cell growth stimulated by human placental conditioned medium distinguished between transient leukemia (TL) and congenital acute myeloid leukemia (AML) in neonates. We then sought to determine whether the application can be expanded if in vitro cell growths are stimulated by recombinant human cytokines including granulocyte-macrophage colony-stimulating factor (rhGM-CSF), interleukin-3 (rhIL-3), stem cell factor (rhSCF) and thrombopoietin (rhTPO).

METHODS

Eight neonates with features indistinguishable from AML were studied. Seven patients had Down syndrome and the eighth a normal phenotype. Bone marrow or peripheral blood mononuclear cells (MNC) were cultured in the presence of rhGM-CSF+rhIL-3+rhSCF or of rhTPO alone. After incubation, granulocyte-macrophage colony-forming units (CFU-GM)-derived colonies and clusters were scored on an inverted microscope. Colony-forming units-megakaryocyte (CFU-MK)-derived colonies were counted with an in situ CD61 immunostained dish. Liquid suspension cultures of MNC were stimulated by rhGM-CSF and/or rhTPO.

RESULTS

CFU-GM-derived colonies and clusters from bone marrow and peripheral blood MNC revealed normal patterns in seven patients. RhTPO-stimulated megakaryocyte colony formation was normal in one patient. Cytospin smears of liquid suspension cultures all showed good myeloid or megakaryocytic maturation consistent with TL rather than AML. One neonate died on the 2nd day of life, but in the seven remaining patients, blasts disappeared from the peripheral blood within 10 months. Among four patients followed long-term, one developed myelodysplastic syndrome at 21 months. This child was given tailored chemotherapy and had a disease-free survival>20 months.

CONCLUSION

In vitro cell growth stimulated by recombinant human cytokines can help to diagnose TL in neonates.

Chemiluminescent determination of leukocyte alkaline phosphatase: an advantageous alternative to the cytochemical assay

The determination of leukocyte alkaline phosphatase (LAP) is used as an aid to diagnose many diseases in the laboratory. For example, it can be used to distinguish chronic myeloid leukemia (CML) from other myeloproliferative disorders (particularly myelofibrosis and polycythemia) and leukemoid reactions (LR). Traditionally, this test is performed with the use of subjective cytochemical assays that assign a score to the level of LAP. Here we present a nonsubjective, quantitative, sensitive, and inexpensive chemiluminescent technique that determines LAP based on the commercial reagent Immulite (AMPPD). To validate this methodology, intact leukocytes obtained from 32 healthy subjects, nine CML patients, and nine LR patients were submitted to the optimized protocol. By measuring the light emission elicited by four concentrations of neutrophils, we were able to estimate the activity of LAP per cell (the slope of the curve obtained by linear regression). A high linear correlation was found between the chemiluminescent result (slope) and the cytochemical score. The slope for healthy individuals ranged between 0.61 and 8.49 (10(-5) mV.s/cell), with a median of 2.04 (10(-5) mV.s/cell). These results were statistically different from those of CML patients (range=0.07-1.75, median=0.79) and LR patients (range= 3.84-47.24, median=9.58; P<0.05).

Primary renal inflammatory malignant fibrous histiocytoma: A diagnostic challenge

Renal inflammatory malignant fibrous histiocytoma (MFH) is an extremely rare lesion and is a great masquerader of common benign renal inflammatory lesions, especially xanthogranulomatous pyelonephritis (XGPN). The clinical presentation of mass with fever and peripheral leucocytosis (marked at times), and marked inflammatory, predominantly neutrophilic, infiltrate obscuring the malignant cells on histopathology, can lead to delay in the diagnosis of this poor prognostic malignant tumor. We present the case of a patient who underwent radical nephrectomy with a clinical diagnosis of renal malignancy, but histopathology showing XGPN. The patient showed an initial clinical response, only to recur two times, ultimately leading to a histological and immunohistochemical diagnosis of inflammatory MFH. The diagnosis, histology, therapeutic options and prognosis of this rare lesion are discussed.

Leukemoid reaction: a diagnostic clue in metastatic carcinoma mimicking classic Hodgkin lymphoma

We report on 2 patients who were initially suspected to have classic Hodgkin lymphoma because of lymphadenopathy and the presence of Reed-Sternberg-like cells. Both patients had an associated leukemoid reaction (using a threshold leukocyte count of 50 000/microL) and were eventually diagnosed with metastatic carcinoma. Disseminated carcinoma can mimic Hodgkin lymphoma clinically, radiologically, and histologically. Reed-Sternberg-like cells may be found in carcinomas, and they represent a particularly challenging diagnostic pitfall for the unwary. When these cells lead to a suspicion of Hodgkin lymphoma, the presence of a leukemoid reaction should prompt the pathologist to question the diagnosis. Misdiagnosis can be avoided by the use of cytokeratin whenever a leukemoid reaction is present in a suspected case of Hodgkin lymphoma.

Evidence of clonality in chronic neutrophilic leukaemia

BACKGROUND

Chronic neutrophilic leukaemia (CNL) is a rare myeloproliferative disorder of elderly patients characterised by sustained neutrophilia and splenomegaly. The diagnosis of CNL requires the exclusion of BCR/ABL positive chronic myelogenous leukaemia (CML) and of leukaemoid reactions (LRs). The differentiation between CNL and LR is problematic because both conditions share similar morphological features; it is also important because patients with CNL generally have a poor prognosis.

AIMS

To determine whether CNL and LR could be distinguished on the basis of different clonality patterns.

METHODS

Blood samples from 52 women were studied using the human androgen receptor gene assay (HUMARA).

RESULTS

Monoclonality was found in the neutrophils in all 17 patients with different myeloproliferative syndromes (MPSs), including those with CNL. In four of the patients with CNL, autologous T cells were also monoclonal, suggesting that they belonged to the neoplastic clone. This finding was in contrast to other MPSs in which T cells were almost always polyclonal. Of nine patients with clinically suspected LR, the neutrophils of five were polyclonal, whereas three patients had monoclonal neutrophils, suggesting that they might be in the process of developing an MPS. Among 26 healthy blood donors, 20 had polyclonal neutrophils and five showed skewed clonality patterns. One case of LR and one normal blood donor were scored "not informative" at the HUMARA locus.

CONCLUSIONS

Clonality studies of blood neutrophils using HUMARA aid in distinguishing female patients with monoclonal CNL from those with LR. For the diagnosis of CNL, monoclonality of the neutrophils should be demonstrated whenever possible.

Relationship between neonatal leukemoid reaction and bronchopulmonary dysplasia in low-birth-weight infants: a cross-sectional study

Leukemoid reaction in low-birth-weight (LBW) infants is a rare, recently documented phenomenon, implicated in the sequence of multiorgan inflammatory diseases of preterm infants. The aim of the present paper is to establish whether a neonatal leukemoid reaction is related to bronchopulmonary dysplasia (BPD) development in LBW infants. The design was a case-controlled, retrospective study of all premature infants (born </=31 weeks' gestation) admitted to the neonatal intensive care unit (NICU) over a period of 3 years, from January 1998 to December 2000. The infants who developed BPD formed the study group, while the remainder without pulmonary sequelae, matched for gestational age formed the control group. Leukemoid reaction was considered a white blood cell (WBC) count >40,000/mm 3. The relation between BPD occurrence and WBC counts was studied by Bayesian analysis, dividing WBC counts in 5 progressive bands of 10,000 WBC/mm 3, starting from <10,000 to >40,000/mm 3. Five of 50 BPD infants studied demonstrated WBC counts >40,000/mm 3, with an incidence of 10%, while no control preterm infants presented neonatal leukemoid reaction; the estimated number difference is statistically significant ( p <0.001). There was no other significant association demonstrated between maternal or neonatal variables and leukemoid reaction, including chorioamnionitis, sepsis, and the use of antenatal steroids. Our findings provide further data for the identification of prematures exposed to pro-inflammatory cytokines in utero; the injury responsible for BPD in a subset of prematures may begin with a transient leukemoid reaction.

Disseminated hepatosplenic mycobacterial infection masking myeloproliferative diseases as leukemoid reaction: a diagnostic pitfall

The distinction of myeloproliferative disease (MPD) from leukemoid reactions due to reactive causes can be difficult. In the presence of simultaneous occurrence of MPD and an established infection, only the demonstration of a clonal marker or prolonged observation can substantiate the diagnosis. We present three cases of MPD presenting as leukemoid reaction due to disseminated hepatosplenic mycobacterial sepsis. There appeared to be an association between MPD and reduced resistance to mycobacterial infection. Clinicians and hematologist should be aware of such a predisposition and possible dual pathology for proper diagnosis, therapy and monitoring of both the infection and the myeloproliferation.

[Chemically-induced paraneoplastic hyperleukocytic lung]

Dyspnea is the principal clinical feature of pulmonary leukostasis, a syndrome called "poumon hyperleucocytaire" in French. It is a common complication of chronic myeloid leukemia. In the course of pulmonary carcinoma, leukocytosis is frequently noted. One of the etiologies is a paraneoplastic syndrome with production of colony stimulating factor. We report a case of pulmonary hyperleukostasis following antineoplastic chemotherapy for pulmonary carcinoma.

Suspected betamethasone-induced leukemoid reaction in a premature infant

The use of antenatal corticosteroids in threatened pregnancies of less than 34 weeks' duration is a valuable tool for assisting fetal lung maturation. Although this practice has existed for over 20 years, little is known about a rare extreme elevation of the newborn's white blood cell count, called a leukemoid reaction. A case of leukemoid reaction is discussed to assist the clinician with the current thought processes and diagnostic differential behind this benign condition.