Hematologic Disorders In Children Research Articles

Reduction of haemoglobin is related to metal mixtures exposure in Chinese preschoolers: Joint effect models

Heavy metal exposure is a known risk factor for hematologic disorders in children, yet the impact of co-exposure to multiple metals remains underexplored. This cross-sectional study investigates the relationship between urinary levels of 23 metals and haemoglobin (Hb) in 1460 Chinese preschoolers. The concentrations of the 23 urinary metals were quantified using an inductively coupled plasma mass spectrometer, while Hb levels were assessed through finger prick blood samples. To evaluate the co-exposure effects, we employed three approaches: Generalized linear regression model, joint effect models including Quantile g-Computation and Bayesian Kernel Machine Regression (BKMR). From the generalized linear regression and Quantile g-computation, urinary uranium, thallium, aluminium, iron and tungsten were correlated negatively with Hb, while urinary barium was correlated positively (all P < 0.05). Moreover, significant negative associations between metal mixtures exposure with Hb were identified in both Quantile g-computation [β (95% CI): -0.083 (-0.132, -0.033), P = 0.0012] and BKMR [90th percentile vs. 50th percentile β (95% CI): -0.238 (-0.368, -0.107), P < 0.001] with aluminium emerging as the primary contributor to this joint effect (weight in Quantile g-computation = 0.399, PIPs in BKMR = 0.896). These findings provide a potential explanation for environmental exposure to metals and Hb-related disease in preschoolers.

Short-Term Follow-up of Blinatumomab in Children with B-Cell Precursor Acute Lymphoblastic Leukemia：Study of a Single Center from China

Background: Acute lymphoblastic leukemia (ALL) is the most common hematologic disorders in children. The 5 years overall survival (OS) has reached more than 90%, but still 20% of patients relapsed. Positive of microscopic residual disease (MRD+) is the important factors for pediatric ALL. Blinatumomab is a combination of CD3 and CD19 bispecific antibody. Previous studies have shown that it has a significant advantage in improving the efficacy and survival of refractory /relapsed (R/R) ALL and MRD+ patients. Blinatumomab has been approved in China for R/R ALL indications in adults and children respectively since Aug 2021 and Apr 2022. So far, there is a lack of research data on ALL in Chinese children. This study mainly discusses the short-term efficacy and safety of Blinatumomab for R/R ALL and MRD+ of children with B-ALL in China. Methods: We collected the patients' information of children with R/R or MRD+ B-ALL treated with blinatumomab from Aug 2021 to Jun 2022 in our single institute from China. Retrospectively analyzed were carried out for the short-term efficacy and safety. Results: since Aug 2021, blinatumomab has been introduced to China. 13 cases were enrolled in this study, including R/R ALL 6 cases and MRD + ALL 7 cases, the median onset age of 9.5 (range 5-14) years old, male: Female =8:5, in the R/R-ALL group, there was 1 case of sustained no remission (NR), 1 case of very early recurrence(<18 months) and 1 case of late recurrence(≥36 months), and 3 cases of early recurrence, ALL of which were isolated bone marrow recurrence for the first time. 3 cases were treated with reinduction chemotherapy before blinatumomab. The mean proportion of blast cells in bone marrow (BM) prior therapy was 34.3 (range 0-96) %. The mean flow cytometry MRD was 30.26 (range 0.11-78.3) %. 3 patients were with no dose uphill due to low tumor load. 3 patients were given uphill 5ug/m2 qd d1-7, 15ug/m2 d8-28, of which 1 was treated for 14 days and 2 for 21 days. The investigator evaluated the efficacy of the treatment and stopped the drug. After treatment, bone marrow morphology was complete response (CR) in 3 cases, of which 2 cases had MRD negative (MRD-), the Cytokine release syndrome (CRS) incidence was 83.3%, 2 cases had CRS grade 2, 3 cases CRS grade 1, and the main manifestations were fever and hypotension. The levels of cytokines were significantly increased in patients with CRS, especially in IL-6, IL-8 and IL-10. The median level of IL-6 in CRS was 3081.8 (range 12.6-10405.0). IL-8 214.5 (range 23-408.0) and IL-10 377.7 (range 6.7-1398.0) (normal value ≤ 4.91) were significantly higher than those before blinatumomab and after CRS disappeared. In the MRD+ ALL group, there were 2 cases of chemotherapy drug intolerance, 1 case of inadequate treatment, and 4 cases of continuous MRD+ after standard chemotherapy. In MRD+ALL group, the BM of All cases were CR before treatment, the mean flow MRD value was 0.63 (range 0.01-4.00) %, the blinatumomab was 15ug/m2 (weight < 45kg) or 28ug (weight ≥45kg) for 7-28 days. After treatment, the MRD of 7 cases were all turned negative and the incidence of CRS was 71%. All of which were CRS grade I. When CRS occurs, the median IL-6 level is 76.4 (range 4.4-271.0) (normal value ≤ 5.3), IL-8 18.7 (range 8.0-35.5) (normal value ≤ 20.6), IL-10 447.3 (range 8.9-2570.0) (normal value ≤ 4.91) Conclusion: The CR rate of R/R pediatric B-ALL was 50%, the MRD- rate was 67%. The rate of MRD turned negative was 100% in MRD+ B-ALL group. In this study, the tolerance of blinatumomab in children with B-ALL was good, and the incidence of CRS was about grade 1/2, and no neurological complications occurred. The occurrence of CRS was mainly caused by the increase of cytokines, especially IL-6, IL-8 and IL-10. The IL-6 of CRS in R/R ALL group was significantly higher than that in MRD+ ALL (Fig.12.798, P=0.007).

Prenatal Exposure to Air Pollution and Immune Thrombocytopenia: A Nationwide Population-Based Cohort Study.

IntroductionImmune thrombocytopenia (ITP) is one of the most common hematologic disorders in children. However, its etiology is still unclear. Epidemiological studies have shown that air pollution is a plausible risk factor in stimulation of oxidative stress, induction of inflammation, and onset of autoimmune diseases. The objective of this article is to examine the effects of prenatal exposure to air pollution on the occurrence of immune thrombocytopenia (ITP) in children.Materials and MethodsThis is a nationwide, population-based, matched case-control study. Using data from Taiwan’s Maternal and Child Health Database (MCHD), we identified 427 children with ITP less than 6 years of age and age-matched controls without ITP between 2004 and 2016. Levels of prenatal exposure to air pollutants were obtained from 71 Environmental Protection Administration monitoring stations across Taiwan according to the maternal residence during pregnancy. Patients who had outpatient visits or admission with diagnosis of ITP and subsequently received first-line treatment of intravenous immunoglobulin or oral glucocorticoids were defined as incidence cases.ResultsPrenatal exposure to particulate matter <10 μm (PM10) in diameter and the pollutant standard index (PSI) increased the risk of childhood ITP. Conversely, carbon monoxide (CO) exposure during pregnancy was negatively associated with the development of ITP.ConclusionCertain prenatal air pollutant exposure may increase the incidence of ITP in children.

Bone Marrow Aspiration Findings in Hematological Disorders in Children

Background: Primary objective was to study bone marrow aspiration(BMA) findings in hematological disorders in children with secondary objective to find correlation between peripheral blood film (PBF) findings with BMA.Material &amp; Methods:It was observational and cross-sectional study conducted on 65 children in age group of 1-18 yrs admitted to Pediatrics Department of Government Medical College, Patiala over period of 1 yr. Inclusion criteria was based on clinical and laboratory parameters. Children were of anaemia, leucopenia and pancytopenia. Complete hemogram, reticulocyte count, PBF smear and bone marrow aspiration were done. The data was analyzed using IBM Statistical Packages for Social Sciences SPSS software version 22.Results:The mean age of study population was 10.39±6.29yrs. 93.8% children presented with pallor followed by fever in 84.6% and lethargy in 66.2%. 62 children were severely anaemic, 33 had bicytopenia, 23 children had pancytopenia. Bone marrow was hypercellular in 59 (90.8%) children. 40 (61.5%) children had megaloblastic anaemia on BMA followed by dimorphic anaemia in 8, Idiopathic thrombocytopenic purpura in 6 children. 4 children each had Megaloblastic anaemia with gelatinous transformation and micronormoblastic anaemia. 2 children had acute lymphatic leukemia and one had aplastic anaemia. The predominant PBF was dimorphic in 30 children, out of whom 22 had megaloblastic anaemia and 8 had dimorphic anaemia on BMA. Conclusions:Bone marrow was megaloblastic in majority (61.5%) of children. There was no significant association found between PBF findings and bone marrow diagnosis.

Radiation-sparing reduced-intensity unrelated umbilical cord blood transplantation for rare hematological disorders in children.

Graft failure is a major pitfall of unrelated umbilical cord blood transplantation (CBT) in children with rare hematological disorders other than acute leukemia, such as acquired and inherited bone marrow failure, myelodysplastic syndrome, juvenile myelomonocytic leukemia, and chronic myeloid leukemia. We developed a less-toxic conditioning regimen for CBT that achieves a higher rate of complete donor chimerism, and retrospectively compared it against two other conditioning regimens for CBT performed at our single institution. The engraftment rate with complete donor chimerism was 100% and 5-year event-free survival (5y-EFS) was 90.9% in patients using our latest regimen (n = 11) of reduced-intensity conditioning (RIC) containing fludarabine (Flu) 180mg/m2, melphalan (MEL) 210mg/m2, and low-dose rabbit anti-thymocyte globulin (LD-rATG) 2.5mg/kg without irradiation (regimen C). Outcomes were better than in patients (n = 10) treated with previous regimens involving irradiation (5y-EFS 30.0%, p = 0.004): regimen A, consisting of myeloablative conditioning containing cyclophosphamide (CY) and total body irradiation (TBI) with 8-12Gy, or regimen B, consisting of RIC with Flu, CY, horse ATG, and thoracoabdominal irradiation (TAI) with 6Gy. In conclusion, Flu/MEL/LD-rATG (regimen C) without TBI/TAI may be preferable as RIC for unrelated CBT in children with rare hematological disorders.

Partial splenectomy in children: Long-term reoperative outcomes☆

PurposePartial, or subtotal, splenectomy (PS) has become an accepted alternative to total splenectomy (TS) for management of hematologic disorders in children, but little is known about its long-term outcomes. Here, we present our institutional experience with partial splenectomy, to determine rate of subsequent TS or cholecystectomy and identify if any factors affected this need. MethodsAll patients who underwent partial splenectomy at a single tertiary children's hospital were retrospectively reviewed from 2002 through 2019 after IRB approval. Primary outcome of interest was rate of reoperation to completion splenectomy (CS) and rate of cholecystectomy. Secondary outcome were positive predictor(s) for these subsequent procedures. ResultsTwenty-four patients underwent PS, at median age 6.0 years, with preoperative spleen size of 12.7 cm by ultrasound. At median follow up time of 8.0 years, 29% of all patients and 24% of hereditary spherocytosis (HS) patients underwent completion splenectomy at median 34 months and 45 months, respectively. Amongst HS patients who did not have a cholecystectomy with or prior to PS, 39% underwent a delayed cholecystectomy following PS. There were no significant differences in age at index procedure, preoperative splenic volume, weight of splenic specimen removed, transfusion requirements, preoperative or postoperative hematologic parameters (including hemoglobin, hematocrit, total bilirubin, and reticulocyte count) amongst patients of all diagnoses and HS only who underwent PS alone compared to those who went on to CS. There were no cases of OPSS or deaths. ConclusionPartial splenectomy is a safe alternative to total splenectomy in children with hematologic disease with theoretical decreased susceptibility to OPSS. However, families should be counseled of a 29% chance of reoperation to completion splenectomy, and, in HS patients, a 39% chance of delayed cholecystectomy if not performed prior to or with PS. Further studies are needed to understand predictors of these outcomes.

A Spectrum of Hematological Disorders in Children with Pancytopenia Based on Bone Marrow Examination in a Tertiary Care Hospital.

IntroductionPancytopenia is a common presentation in the pediatric population. It is a manifestation of various diseases, and its etiology can be explained on the basis of bone marrow examination. The study aims to determine the etiological factors leading to pancytopenia via bone marrow examination in pediatric patients presenting in our hospital.Materials and methodsThis retrospective cross-sectional study was conducted in the Department of Pathology at a public sector tertiary care hospital. Data were recorded by convenience sampling from the patients’ database from January 2015 to April 2018. Patients aged 2 months to 15 years who had pancytopenia on peripheral blood smear and were admitted for bone marrow examination were included in the study. Patients who were beyond these age limits, diagnosed cases of aplastic anemia and leukemia, and those with a recent history of blood transfusion were excluded from the study. The analysis was done via the Statistical Package for Social Sciences (SPSS) v.23.0 (IBM SPSS Statistics, Armonk, NY, USA), and descriptive statistics were applied.ResultsOf 115 cases, 58 (50.4%) were males and 57 (49.6%) were females. Megaloblastic anemia was present in 32 (27.8%) patients, and it was the most common cause of pancytopenia. Non-malignant disorders were seen in 95 cases (82.6%) and malignant disorders were seen in 20 (17.4%) cases.ConclusionMegaloblastic anemia is the most common cause, and acute lymphoblastic leukemia is the most common malignant cause of pancytopenia in children. There was no significant gender predilection among causes of pancytopenia.

Hematologic Disorders in Children with Continuous Renal Replacement Therapies.

The objective of this study was to analyze hematologic disorders, coagulation disorders, and transfusion requirements in children with continuous renal replacement therapies (CRRT). This is a retrospective analysis of a prospectively collected database of children receiving CRRT between 2010 and 2015. Patient characteristics, CRRT parameters, hematologic and coagulation parameters, and need for transfusions were recorded and analyzed. We compared patients after heart surgery and noncardiac patients, those requiring extracorporeal membrane oxygenation (ECMO) and those without ECMO, and patients with different anticoagulation therapies: heparin and citrate. Eighty-seven patients were included (69% after heart surgery). Thirty-four percentage of patients required ECMO. Hematologic alterations throughout the therapy included a descent in hematocrit from 33.6% to 30.3% (p = 0.002) and in platelet count from 159.291 to 101.163 (p < 0.001). Coagulation parameters improved as international normalized ratio decreased from 1.5 to 1.2 (p < 0.001), fibrinogen increased from 328 to 437 mg/dl (p = 0.04), and activated partial thromboplastin time (APTT) was normalized. There were no significant differences in hematologic parameters or need for blood products between patients after heart surgery and the rest of patients, or between patients receiving heparin or citrate for anticoagulation. Ninety percentage of patients received blood products, but patients on ECMO and those who deceased required more transfusions than the rest of the patients (p < 0.01). We conclude that children undergoing CRRT show a descent in hematocrit and platelet count and require large amounts of blood products, especially those ECMO and patients who died.

Cutaneous Hematolymphoid and Histiocytic Proliferations in Children.

This article focuses on cutaneous hematopoietic neoplasms that are more likely to be encountered in the pediatric age-group and includes both lymphoproliferative and histiocytic disorders. The cutaneous hematologic disorders in children have a different epidemiologic profile to what is seen during adulthood. Although mycosis fungoides is the most frequent form of cutaneous lymphoma in adults, it is very rare in children. Because lymphoblastic leukemias and lymphomas are more frequent in the pediatric setting, cutaneous leukemic infiltrates are relatively common in this age-group. Similarly, histiocytic disorders are more common in children, particularly Langerhans cell histiocytosis and juvenile xanthogranuloma. Notably, the histiocytic disorders have undergone significant modifications on their nomenclature in the basis of the molecular characteristics that are present in them. A summary of the most frequent cutaneous hematopoietic disorders in children will be discussed further in this review.

Application of GATA-3 gene marker in the detection of hematologic disorders in children.

The aim of the present study was to investigate the use of GATA-3 markers in the detection of hematologic disorders in children. In total, 35 pediatric patients diagnosed with blood disease and treated in Henan Red Cross Blood Center from January 2014 to June 2015 were selected for the observation group. Another 32 healthy children were selected for the control group. The differences in the GATA-3 mRNA expression levels between the control and observation groups were detected via reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The differences in the GATA-3 protein expression levels were detected via enzyme-linked immunosorbent assay (ELISA) and western blot analysis. Compared with those in the healthy children, the mRNA expression levels of GATA-3 in patients with hematologic malignancies, acute lymphoblastic leukemia, myeloproliferative disorder, acute non-lymphocytic leukemia or thrombocytopenic purpura were significantly higher, and there were statistically significant differences between the groups (P<0.05). The results of ELISA showed that the GATA-3 protein expression levels in patients with hematologic malignancies (241.3±42.6 µg/l), acute lymphoblastic leukemia (196.3±21.6 µg/l), myeloproliferative disorder (284.2±45.1 µg/l), acute non-lymphocytic leukemia (269.3±31.4 µg/l) or thrombocytopenic purpura (272.1±39.1 µg/l) were significantly higher than those in healthy subjects (69.3±15.2 µg/l). The results of western blot analysis were consistent with those of ELISA. Based on our results, the expression levels of GATA-3 in healthy children and pediatric patients with blood diseases exhibit significant differences, and can be used as important markers for the clinical diagnosis of blood diseases in children.

Chimerism in pediatric hematopoietic stem cell transplantation and its correlation with the clinical outcome

Hematopoietic stem cell transplantation (HSCT) is the only hope to cure many inherited and acquired hematological disorders in children. Monitoring of chimerism helps to predict the post-transplantation events, with the intention to enhance the long-term disease free survival (DFS). The study aimed to investigate the importance of early chimerism detection to predict the clinical outcome following HSCT. The study included nine recipients (six β-thalassemia and three severe aplastic anemia patients) and their 10/10 HLA identical sibling donors. Chimerism detection was performed by analysis of short tandem repeat (STR) polymerase chain reaction (PCR) for detection and quantification of the relative amounts of donor and recipient cells present on day +28. Peripheral blood (PB) was the main stem cell source for HSC transplantation. Disease free survival (DFS) was 71.4% while overall survival was 85.7% for PBSC transplants at the median follow up period of 4years. The early detection of chimerism by PCR-STR analysis for children with β-thalassemia and aplastic anemia correlated with the outcome of HSCT in 8 (88.8%) patients. Complete chimerism was associated with disease-free survival while mixed chimerism and autologous patterns were associated with poor prognosis. In conclusion, early chimerism testing is clinically important in prediction of outcome after allogeneic HSC transplantation.

Prevalence of Hematological Disorders among Children with Brucellosis

Background: Brucellosis is a zoonotic systemic infection due to infection by Brucella organisms with a various clinical manifestations and complications. Hematological disorders is the most common and serious complications among children. Objectives: Our study aimed to evaluate frequency of hematological complications among brucellosis infected children. Patients and Methods: All 75 patients enrolled in the study with fever more than 5 days, arthralgia , myalgia, low back pain , hematological disorders and positive serology test ( positive results when the tires &gt; 1:80 ) were referred to the infectious diseases unit in King Khalid hospital ,Al-kharj city ,K.S.A. during  April 2013 to August 2015, and C.B.C., blood culture and bone marrow study were made for all patients .Results: out of 75children with brucellosis with age 5-18 y, 63 (84%) gave a history of raw animal milk ingestion and 33 patients 44% had a positive family history of brucellosis. The commonly presenting symptoms and signs included; excessive sweating 43 patients (57.3%) bone aches 65 patients (62%) chills 40 patients (53.3%), arthritis 27 patients (36%). Hepatomegaly 10 patients (13.3%) and splenomegaly    11 patients (14.6%). The most commonly detected hematological manifestations included; anemia in 34 patients (45%). leukopenia in 30 patients (40%) and leukocytosis in 18 patients (24%). Meanwhile, pancytopenia was detected in 24 patients (32%). Positive blood culture for brucella was seen in 30 patients (40%). B. melitensis from 26 patients (34.6%) was cultured in vitro. Out of 15 BM aspiration cultures, 5 were positive for B. melitensis while 10 cultures were negative. Out of 24 patients (32%) with pancytopenia, 17 patients 71% presented with bone aches and weakness, 12 patients 50% presented with sweating and chills,12 patients 50%  had petechiae and purpura , 12 patients50% had splenomegaly and also 9 patients 37.5% had hepatomegaly.Conclusions: Our study showed that the clinical manifestations and hematological disorders in children with brucellosis are 45% of patients were anemic, 40% were leukopenia, pancytopenia were in 32% while leukocytosis were in 24% similar to that in the adults; specially in endemic areas like K.S.A.Â

Alternative donor transplant of benign primary hematologic disorders.

Hematopoietic SCT is currently the only curative therapy for a range of benign inherited and acquired primary hematologic disorders in children, including BM failure syndromes and hemoglobinopathies. The preferred HLA-matched sibling donor is available for only about 25% of such children. However, there has been substantial progress over the last four decades in the use of alternative donors for those without a matched sibling-including HLA-matched unrelated donors, HLA-haploidentical related donors and unrelated-donor umbilical cord blood-so that it is now possible to find a donor for almost every child requiring an allograft. Below, we summarize the relative merits and limitations of the different alternative donors for benign hematologic conditions, first generally, and then in relation to specific disorders, and suggest recommendations for selecting such an alternative donor.

Diagnostic outcome of bone marrow aspiration in a pediatric center in Kolkata, India

Objectives: To study the spectrum of hematological disorders in children at a tertiary care centre in Kolkata, India. Settings: This study was conducted at the department of Paediarics and the department of Pathology of Dr. B. C. Roy PGIPS, Kolkata. The study period was from January 2012 to December, 2014. Methods: A retrospective analysis of charts of those patients who underwent bone marrow examination (aspiration) was made. Charts were analyzed in detail regarding history, examination and investigations. All findings were entered on a standard proforma. Results: BMA from 200 patients were analyzed. Nutritional anemia contributed highest number of cases among the nonneoplastic group. Acute lymphoblastic leukemia was the commonest malignant hematological disorder in the present study. Conclusion: Common haematologic disorders in our setting are nutritional anaemias and leukaemias. There is need to expand the scope of laboratory investigations beyond morphology.

Erratum to: Common Hematological Disorders in Children

Erratum to: Common Hematological Disorders in Children

Common Hematological Disorders in Children

It is common for primary care physicians to be faced with children with hematological disorders in everyday practice. The article seeks to provide realistic information for the first-contact physician in handling common hematological diseases in children. Practical step-wise approach to understanding and investigating anemia and bleeding disorders is illustrated. Requirement of iron in normal children and management of iron deficiency anemia (IDA) and thalassemia is explained. The gold standard for IDA continues to be ferrous sulphate which has good bioavailability and is inexpensive. There is emerging concept of delayed clamping of umbilical cord at birth, particularly in regions with widespread IDA, to augment iron stores in infancy. Typical case scenarios of children with immune thrombocytopenia (ITP) and hemophilia are provided to facilitate the understanding of management in day to day practice. The vital role of the medical practitioner in shared care of patients with acute lymphoblastic leukemia and febrile neutropenia is emphasized. A risk based treatment algorithm for febrile neutropenia is provided.

Emerging menu options for gonadal reincarnation

Emerging menu options for gonadal reincarnation

Ethanol lock therapy in pediatric hematology and oncology

Central venous catheters are essential for treatment of cancer and hematologic disorders in children. Central line-associated bloodstream infection (CLABSI) is the most common important complication and can lead to serious sequelae. Conventional antibiotic treatment is often unsuccessful. Ethanol lock therapy (ELT) has been shown to prevent CLABSI in various patient groups and might also be beneficial as adjunctive treatment for active infection. Efficacy and safety have not been adequately studied in the pediatric hematology/oncology population. Catheter occlusion and intraluminal clots have been reported. Routine use of ELT should not be recommended in this population until more data are available.

Describing and Quantifying Asthma Comorbidty: A Population Study

BackgroundAsthma comorbidity has been correlated with poor asthma control, increased health services use, and decreased quality of life. Managing it improves these outcomes. Little is known about the amount of different types of comorbidity associated with asthma and how they vary by age.Methodology/Principal FindingsThe authors conducted a population study using health administrative data on all individuals living in Ontario, Canada (population 12 million). Types of asthma comorbidity were quantified by comparing physician health care claims between individuals with and without asthma in each of 14 major disease categories; results were adjusted for demographic factors and other comorbidity and stratified by age. Compared to those without asthma, individuals with asthma had higher rates of comorbidity in most major disease categories. Most notably, they had about fifty percent or more physician health care claims for respiratory disease (other than asthma) in all age groups; psychiatric disorders in individuals age four and under and age 18 to 44; perinatal disorders in individuals 17 years and under, and metabolic and immunity, and hematologic disorders in children four years and under.Conclusion/SignificanceAsthma appears to be associated with significant rates of various types of comorbidity that vary according to age. These results can be used to develop strategies to recognize and address asthma comorbidity to improve the overall health of individuals with asthma.

Cutaneous hematologic disorders in children

To determine and list the clinical and pathological features of cutaneous hematologic diseases in childhood. We retrospectively analyzed the data for 51 patients up to 15 years of age, who presented with primary cutaneous hematologic disorders according to the WHO-EORTC classification, at Necker-Enfants Malades Hospital, Paris, France, over a 17-year period. The cases were classified into the following diagnostic categories: CD30+ T-cell lymphoproliferative disorders (24) all consisting of lymphomatoid papulosis (LyP, 24), lymphoblastic lymphoma (LL, 7), acute leukemias (AL, 7), mycosis fungoides (MF, 5), Epstein-Barr virus-related lymphoproliferative disorders (EBV-related LPD, 5), T/NK-cell lymphoma, nasal type (1), γ/δ T-cell lymphoma (1), and panniculitis-like T-cell lymphoma (1). We encountered a majority of LyP. No secondary lymphoma was found in LyP patients with a median follow-up of 8 years. 29% and 80% of LyP and MF patients, respectively, presented with pityriasis lichenoides chronica (PLC) before onset of disease. Owing to a frequently misleading clinicopathological presentation, MF patients were first underdiagnosed. Clinicopathological features of LL and AL were highly stereotypical, leading to the diagnosis being suspected and confirmed more promptly. In the latter patients and in EBV-related LPD patients, skin lesions usually led to the discovery of systemic disease. Distribution of cutaneous hematologic diseases seems to be different in adults and in children aged <15-year old. PLC was strongly correlated with MF and LyP. Physicians must be made aware of the stereotypical clinical presentations of LL and AL to allow prompt diagnosis and treatment.