Congenital thrombotic thrombocytopenic purpura with novel mutations in three unrelated Turkish children.

Congenital thrombotic thrombocytopenic purpura (TTP) is an inherited disease caused by mutations in the ADAMTS 13 gene and has been reported to have diverse ages of presentation, ranging from the newborn period to adulthood. Herein, we present three cases of congenital TTP who were symptomatic during childhood (neonatal period, 7 and 10 years) and were each initially given different diagnoses. Congenital TTP was later diagnosed by molecular analysis and responsiveness to fresh frozen plasma. Three novel mutations in a homozygous state were identified in these patients: c.1308G>C, c.428T>C (p.Ile143Thr) and c.1709A>G (p.Tyr570Cys).

Defective UNC13D gene-associated familial hemophagocytic lymphohistiocytosis triggered by visceral leishmaniasis: a diagnostic challenge.

BACKGROUND: Visceral leishmaniasis (VL) triggered genetic hemophagocytic lymphohistiocytosis (HLH) is clinically challenging. OBSERVATIONS: One-year-old VL-HLH patient improved after liposomal-amphotericin-B therapy, but subsequently deteriorated, although bone marrow amastigotes disappeared. Symptoms resolved after 8 weeks of HLH-2004 therapy but recurred upon cessation. Homozygous UNC13D gene 627delT mutation was identified however stem cell donor was unavailable. The patient died at age 4 years after central nervous system attacks and HLH recurrences. CONCLUSIONS: VL in HLH patients does not exclude a genetic etiology and requires structured clinical management. VL should be excluded in all HLH patients in endemic regions before immunochemotherapy, which is recommended for VL-HLH patients unresponsive to VL treatment and/or reactivated.

Association of nonimmune hydrops fetalis with familial hemophagocytic lymphohistiocytosis in identical twin neonates with perforin His222Arg (c665A>G) mutation.

BACKGROUND: This is the first study demonstrating that nonimmune hydrops fetalis (NIHF) in identical twin neonates is associated with biallelic gene defect causing familial hemophagocytic lymphohistiocytosis. OBSERVATIONS: Preterm male twins (31(4/7) wk) with NIHF and hepatosplenomegaly gradually developed pancytopenia, hyperferritinemia, hyponatremia, hypoalbuminemia, and elevated alanine aminotransferase, aspartate aminotransferase, bilirubin, and lactate dehydrogenase levels. Suspected sepsis led to antibiotic therapy. Upon detection of hemophagocytosis in bone marrow, multiorgan failure and pulmonary bleeding led to death. Homozygous His222Arg (c665A>G) mutation was identified in Perforin. CONCLUSIONS: Familial hemophagocytic lymphohistiocytosis should be considered in first days of NIHF cases to have chance for HLH-2004 therapy. Missense mutations of Perforin codon His222 may lead to intrauterine presentation.

Recurrent macrophage activation syndrome associated with heterozygous perforin W374X gene mutation in a child with systemic juvenile idiopathic arthritis.

BACKGROUND: Recurrent macrophage activation syndrome (MAS) is rarely reported. AIM: To describe recurrent MAS in a 2.5-year-old girl with systemic juvenile idiopathic arthritis and heterozygous perforin mutation, which may have a role in the patient's first recurrence despite use of the HLH-2004 treatment protocol. OBSERVATIONS: In the presented case, MAS was initially controlled after the addition of etoposide to the treatment regimen. However, recurrence occurred 6.5 months after cessation of the HLH-2004 protocol. Subsequent recurrences may have occurred because of the family's noncompliance with treatment. CONCLUSIONS: The patient's extremely high serum ferritin level (267,054 ng/mL) and the recurrent course of MAS may have been because of the coexistence of juvenile idiopathic arthritis and heterozygous perforin W374X mutation. We suggest to search for mutations in HLH genes in recurrent MAS cases.

A rare metabolic complication of acute lymphoblastic leukemia in childhood: lactic acidosis.

A 13-year-old boy presented with nausea, fatigue, weight loss, and bone pain for two months. Complete blood count and serum renal and liver function tests were all normal. Blood gas analysis revealed severe metabolic acidosis with high anion gap. Lactate level was 61.2 mmol/L. Abdominal ultrasonography yielded bilateral nephromegaly and hepatomegaly with increased echogenicity. Peripheral blood smear revealed 2% blasts. Bone marrow aspiration showed 'Common ALL Antigen'-negative acute lymphoblastic leukemia by flow cytometric analysis. Metabolic acidosis dissolved as soon as chemotherapy was begun. Lactic acidosis at the presentation of acute lymphoblastic leukemia--especially with low tumor burden--is a very rare and almost always fatal complication. Our patient is still alive and in remission, which is a point of interest in this child.

Prenatal diagnosis of hemoglobinopathies in Hacettepe University, Turkey.

Between 1983 and 2008, prenatal diagnostic procedures for identifying hemoglobinopathies were performed in 947 at-risk fetuses. Seventy-six percent of the fetuses were at risk for ß-thalassemia major and 16% for sickle cell anemia; only a small percentage (7%) were at risk for compound heterozygosity of ß-thalassemia and an abnormal hemoglobin of the ß chain. The results of the study showed that ß gene mutations in hemoglobinopathies have a very broad spectrum. Seven hundred and thirty of the 947 fetuses examined using the DNA technique showed 88 different combinations of 27 different mutations. Although the number of fetuses evaluated was far below the desired target, the termination of 261 affected fetuses provided both psychological and economic relief for the parents and was economically beneficial for the country in the long term.

The frequency of A91V in the perforin gene and the effect of tumor necrosis factor-α promoter polymorphism on acquired hemophagocytic lymphohistiocytosis.

OBJECTIVE: Numerous acquired etiological factors, such as infections, malignancies, and collagen tissue disorders, are involved in the development of acquired hemophagocytic lymphohistiocytosis (AHLH). Not everyone with the same etiological factors developments AHLH, which suggests the role of additional genetic or environmental predisposing factors that remain to be identified. METHODS: Perforin gene A91V missense transition (C>T change at position 272 in exon 2 of the perforin gene) and TNF-α gene promoter-1031 T>C nucleotide substitution are 2 candidate genetic predisposing factors due to their potential to alter inflammatory responses. In the present study these changes were investigated in healthy controls and AHLH patients. RESULTS: A91V transition was observed in 7 of the 159 (4.4%) controls. Among the 44 AHLH patients, 5 (11.3%) were heterozygous and the difference in the frequency of A91V transition, although striking (odds ratio: 2.8), was not statistically significant (p=0.09). All A91V-positive patients had infection. TNF-α-1031 T>C polymorphism was examined in 164 healthy controls and 40 AHLH patients, and the CC risk-elevating genotype was noted in 7 (4.3%) of the controls and 1 (2.5%) of the AHLH patients. The frequency of C and T alleles was 22.5% (n=18) and 77.5% (n=62) among the AHLH patients, and 22% (n=72) and 78% (n=259) among the controls, respectively. There wasn't a statistically significant difference between the groups in terms of allele frequencies (p>0.05). CONCLUSION: The present results indicate that compared to controls, A91V mutation was 2.8-fold more prevalent (according to the odds ratio) in the AHLH patients. A91V mutation is not uncommon in the general population and increases the risk of AHLH in patients with an underlying condition, especially those with an underlying infection.

Hemophagocytosis associated with leukemia: a striking association with juvenile myelomonocytic leukemia.

The aim of this study was to describe the characteristics and outcome in a group of pediatric patients with hematological malignancies who developed hemophagocytosis at diagnosis or during the disease course. Eight patients with hematological malignancy and associated hemophagocytosis were included. The initial diagnosis was juvenile myelomonocytic leukemia (JMML) in five, nonlymphoblastic leukemia (ANLL) in two, and T-cell lymphoma associated with myeloproliferative syndrome in one patient. Hemophagocytosis was concomitantly present at the time of diagnosis of the primary disease in four of the five patients with JMML and in the two patients with ANLL. Three had abnormalities related to chromosome 8 [(trisomy 8, monosomy 8, and t (8;13) (p11; p12)], and one had inversion 16. Multiple chromosomal losses were present in one patient, including both chromosomes 8 and 16. Bone marrow karyotyping revealed 46, XX; 47, XXX mosaicism in one patient. Two patients had PTPN11 mutation and one patient k-RAS mutation. The patients with JMML and neurofibromatosis (n = 2), the patient with lymphoma and t (8;13) positive AML, and a fourth patient with PTPN11 mutation did not remit and had unfavorable outcomes.

Measles, mumps, and rubella antibody status and response to immunization in children after therapy for acute lymphoblastic leukemia.

Seventy-seven patients with acute lymphoblastic leukemia (ALL) who were in complete remission and whose therapies had been stopped for at least 6 months before enrollment in this study were retrospectively analyzed regarding their antibody status for measles, mumps, and rubella, with the aim to demonstrate the seropositivity rate after treatment in the authors' group. Each patient's serum samples were analyzed by enzyme-linked immunosorbent assay (ELISA) method to determine the antibody titers before and after immunization. Measles serology was available in 77 children; 45 (58%) were seronegative. Initial ages of measle-seronegative patients were statistically lower than those of seropositive cases (median 3.29 versus 4.91 years, respectively). Mumps serology was available in 76 children; 36 (47%) were seronegative. Mumps-seropositive cases tended to have more frequent previous history of infection than seronegative cases (55.0% versus 28.6%, respectively, P = .05). Rubella serology was available in 76 children, and 20 (26.3%) were seronegative. It was determined that initial ages of rubella-seronegative patients were statistically lower than those of seropositive cases (median 3.03 versus 4.32 years, respectively). The authors concluded based on the results of their study that at a median of 3.31 years after completion of chemotherapy for ALL, the majority of cases had antibody levels lower than protective values for measles (58.4%); however, these values were 47.3% for mumps and 26.3% for rubella. Seroconversion rates after measles (55%) and mumps vaccination (57.1%) were still low. However, in the available cases, relatively adequate response to rubella vaccination (92.3%) was observed.

Fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin (FLAG-IDA) for the treatment of children with poor-prognosis acute leukemia: the Hacettepe experience.

Fludarabine, cytarabine, granulocyte colony-stimulating factor (G-CSF), and idarubicin (FLAG-IDA) regimen has been proven to be a potentially useful chemotherapy regimen for relapsed or poor-prognosis childhood leukemia. The aim of the study was to evaluate complete remission (CR) rate, toxicity, and overall survival of children with poor-prognosis acute leukemia who received the FLAG-IDA regimen. Furthermore, the authors investigated the children who achieved CR following FLAG-IDA treatment regarding their eligibility for allogeneic hematopoietic stem cell transplantation (HSCT). Between January 2002 and April 2007, 25 children with poor-prognosis acute leukemia were treated with FLAG-IDA regimen in our center. Of the 25 children (16 AML, 9 ALL) with poor-prognosis acute leukemia, 7 (28.0%) received 1 cycle, 17 (68.0%) received 2 cycles, and 1 (4%) received 3 cycles of FLAG or FLAG-IDA regimen. After 44 cycles of FLAG-IDA or FLAG regimen, 10/25 (40%) children were nonresponders, 15/25 (60.0%) showed CR. Five (20%) of these patients in CR who underwent allogeneic HSCT are still in remission. The remaining 20 (80.0%) children were lost due to infection or relapse of the primary diseases. The overall survival of patients who are still alive and underwent allogeneic HSCT (mean: 40.6 ± 4.7, median: 40, range: 34-46 months) was longer than that of patients (mean: 5.5 ± 4.3, median: 4, range: 1-15 months) who did not undergo allogeneic HSCT. The CR rate was quite high in the present study using the FLAG-IDA regimen, and the authors believe this regimen is a possible option prior to allogeneic HSCT in children with poor-prognosis acute leukemia.

Infectious mononucleosis in Turkish children.

The aim of this study was to analyze the demographic, clinical and laboratory characteristics and prognoses of children diagnosed with infectious mononucleosis (IM). The demographic features, referral complaints, clinical and laboratory findings, follow-up, and prognoses of 44 patients diagnosed with IM between January 2000 and June 2006 at the Infectious Diseases Department of Hacettepe University Ihsan Dogramaci Children's Hospital were analyzed retrospectively. The children suspected of IM based on clinical findings and whose diagnoses were proven by serological tests were enrolled in the study. In addition, the patients were divided into four groups -namely, age 0-4, age 5-8, age 9-12 and age 13-16, and the differences among groups were investigated in terms of their clinical and laboratory findings. The patients were aged between 3 months and 16 years. The median age was 4, and 56.8% of patients were below age 5. The male/female ratio was 1.6. No statistically significant variation was observed in the seasonal distribution of patients (p = 0.131). The most common referral complaints were swollen cervical lymph nodes or swollen neck (68.1%), followed by fever (43.1%) and sore throat (25%). Lymphadenopathy (79.5%), tonsillopharyngitis (72.7%), splenomegaly (34%), and hepatomegaly (25%) were the most common physical examination findings. Leukocyte count was normal in 68.3% of the cases. Leukocytosis was detected in 29.5% of the patients, and leukopenia in 2.2%. Lymphocytosis was detected in 44.7% of patients. Downey cell was detected in the peripheral blood smear of 23.6% of patients, and thrombocytopenia in 11.3%. Elevated alanine aminotransferase and aspartate aminotransferase levels were detected in 61.9% and 90.4% of patients who were investigated for these parameters, respectively. The clinical, hematological and biochemical findings of patients did not vary significantly among age groups (p > 0.05). Only one complication (hemophagocytic syndrome) was observed in one patient.

An unusual presentation of pediatric acute lymphoblastic leukemia with parotid gland involvement and dactylitis.

Mumps infection during the course of childhood acute lymphoblastic leukemia (ALL) treatment has been reported to have a mild course and this was related to the intrinsic low cytopathological effect of the virus, contrasting with the severe course of measles and Varicella zoster virus infections in immunocompromised patients. Herein, we present a three-year-old girl, who was previously vaccinated against mumps infection, admitted with bilateral parotid swelling, dactylitis and serum immunoglobulin M positivity for mumps infection and diagnosed to have ALL with bilateral persistent parotid involvement, inconsistent with mumps infection. Acute leukemia should be suspected during the atypical course of any disease during childhood. Besides, mumps infection at presentation of ALL, as similar to infection emerging during the period of the leukemia treatment, has a mild course.

Parvovirus B19-induced persistent pure red cell aplasia in a child with T-cell immunodeficiency.

Persistent pure red cell aplasia can be a manifestation of parvovirus B19 infection in immunocompromised hosts. Failure of the humoral immune response to clear parvovirus B19 in such patients results in persistent pure red cell aplasia. The authors describe a child who had T-cell immunodeficiency and persistent pure red cell aplasia due to parvovirus B19 infection. Interestingly, they detected human parvovirus B19 genome by polymerase chain reaction (PCR) not in the peripheral blood, but in the bone marrow specimen of the patient. In their patient, T-cell immunodeficiency may have caused impaired B-cell activation and failure of effective humoral immune response to neutralize the virus. Additionally, before the diagnosis of pure red cell aplasia, IVIG treatment given at a dosage of 400 mg/kg/day with 3-week intervals may result in sufficient neutralization of peripheral blood parvovirus B19, whereas it may not be sufficient for the neutralization of parvovirus B19 genome in bone marrow. Thus, peripheral blood parvovirus B19 serology (IgM and IgG) and PCR were negative, whereas bone marrow aspiration sample was positive for parvovirus B19 PCR in this patient. Reticulocytopenia and severe anemia may warn the physicians of parvovirus B19 infection, especially in immunocompromised children. Diagnosis may require demonstration of absence of late erythroid precursors in the bone marrow as well as serologic testing and detection of parvovirus B19 genome by PCR in the serum and/or bone marrow samples of the patient.

Hydrops fetalis associated with chorioangioma and thrombosis of umbilical vein.

Placental chorioangioma and thrombosis of an umbilical vein varix are rare etiologic factors of non-immune hydrops fetalis. Herein, we report a patient who had hydrops fetalis associated with placental chorioangioma and thrombosis of an umbilical vein varix. This is the first report of coexistence of non-immune hydrops fetalis with placental chorioangioma and thrombosis of an umbilical vein varix.

Purpura fulminans as the presenting manifestation in a patient with juvenile SLE.

We present a 12-year-old girl with systemic lupus erythematosus and associated antiphospholipid syndrome who developed an unusual manifestation of purpura fulminans in an accelerated fashion. The patient improved after prompt treatment with anticoagulants, aggressive immunosuppressive drugs and plasmapheresis. This is the first pediatric case of purpura fulminans due to secondary antiphospholipid syndrome of systemic lupus erythematosus. We suggest that SLE patients with lupus anticoagulant should be followed closely for similar complications.

Mild clinical phenotype and subtle radiographic findings in an infant with cartilage-hair hypoplasia.

Cartilage-hair hypoplasia (CHH) is one of the well-known immuno-osseous dysplasias (IOD), which are a combination of skeletal dysplasia and immunodeficiency. It is characterized by disproportionate short stature, fine sparse hair, ligamentous laxity, hematological abnormalities with anemia, a predisposition to malignant tumors, and recurrent infections usually due to cellular and/or humoral immunodeficiency. However, there is a significant overlap of clinical findings among the other IODS such as Schimke's IOD. Here, we present a case of CHH with mild skeletal changes and immunological findings associated with recurrent otitis media, neutropenia, and lymphopenia. With this report, we once more emphasize the difficulty in assessing young individuals with CHH presenting with mild ectodermal findings and subtle radiographic changes.

Malignancy-associated hemophagocytic lymphohistiocytosis in pediatric cases: a multicenter study from Turkey.

This study evaluates the clinical and laboratory data of children with secondary hemophagocytic lymphohistiocytosis (sHLH) related to malignancy. Charts of patients who met the diagnostic criteria for sHLH associated with malignancy between January 2000-2006 at six different hospitals in Turkey were reviewed retrospectively. The diagnosis of HLH had been established by bone marrow aspiration in 27 patients, cerebrospinal fluid and bone marrow aspiration in one patient and lung-liver biopsy in another. Twenty-nine children were diagnosed as having sHLH related to malignancy. Twenty cases (18 ALL and 2 AML) with acute leukemia (10 girls/10 boys, median age: 8 years [3-14 years]) were found to have sHLH. Five patients with acute leukemia had HLH at the time of diagnosis (Group 1a), and 15 patients with acute leukemia were diagnosed as having sHLH during therapy (Group 1b), namely reactive sHLH associated with the chemotherapy. Nine patients, including two cases each of rhabdomyosarcoma, neuroblastoma, Hodgkin disease, and non-Hodgkin lymphoma (NHL) and one case with Langerhans cell histiocytosis, were diagnosed as having concomitant hemophagocytosis at the initial evaluation of the tumor (Group 2). Fever, anemia, and hypertriglyceridemia were present in all sHLH cases of all three groups. Hepatomegaly was detected in 60.0%, 73.3%, and 88.8% of the three groups, respectively. Splenomegaly was more frequent in patients of Groups 1a (60.0%) and 2 (88.8%) than in those of Group 1b, the reactive ones (13.3%). Hypofibrinogenemia was detected in all patients of Group 1a and Group 2. Low level of fibrinogen was present in 91.6% of patients in Group 1b. All patients in Group 1b (100%) had neutropenia and thrombocytopenia. Neutropenia was found at rates of 60.0% and 55.5% in Group 1a and Group 2, respectively. Thrombocytopenia was detected in 80.0% of patients in Group 1a and 77.7% in Group 2. The overall mortality rate was 34.4% (10 cases) in our series of 29 children with sHLH; 50% of deaths were directly attributable to HLH. Pediatric malignancy-associated HLH patients have been commonly described as case presentations or in a review of the literature. We believe that our cohort, compiling 29 children regarding the association between malignancy and HLH, will be useful for pediatricians who are interested in this still mysterious topic.

Serum Erythropoietin Levels in Pediatric Hematologic Disorders and Impact of Recombinant Human Erythropoietin Use.

OBJECTIVE: In anemic patients, the correlation between serum erythropoietin (sEpo) level and the severity of anemia has been reported previously. However, in different anemia groups, different sEpo levels are measured in patients with similar hemoglobin levels and the etiology of this situation could not be explained. METHODS: We evaluated hemoglobin and sEpo levels in 31 iron deficiency anemia, 26 Fanconi anemia (FA), 21 thallasemia intermedia (TI), 15 acute lymphoblastic leukemia (ALL) patients at presentation and 12 healthy controls. RESULTS: In all disease groups, an inverse linear correlation was shown between hemoglobin and logarhytmic sEpo level. The covariance analyses according to corrected hemoglobin levels exhibited the highest sEpo level in FA, followed by ALL, TI and iron deficiency anemia, sequentialy. CONCLUSION: There was no statisticaly significant difference of sEpo levels in FA patients in terms of androgen treatment and this finding supports that androgen affects erythropoisis directly, and has no effect on erythropoietin. The results indicate that there is no erythropoietin deficiency in the anemia of these patients and the admnistration of exogenous erythropoietin offers no clinical benefit.

Transient depletion of innate immunity in varicella infections in otherwise healthy children.

OBJECTIVE: Varicella is a common childhood infection and has a number of complications in the unvaccinated population. Perforin, found in natural killer cells, is important for the killing of virally infected cells. For this reason, the aim of this study was to determine natural killer cell count and activity, perforin expression, and Fas and soluble Fas ligand (sFas-L) levels in immunocompetent children with varicella infection and define any possible relations between the levels and varicella complications. METHODS: Forty children were analyzed at diagnosis and on the 15th day of varicella infection. There was a significant difference in hemoglobin levels and leukocyte and platelet counts between days 0 and 15. RESULTS: Thirteen (32%) patients were found to be lymphopenic. Natural killer cell count and activity were significantly higher on day 15 when compared to values at diagnosis. The Fas-mediated apoptotic pathway was found to be active in acute varicella infection because Fas and sFas-L levels at diagnosis were higher than values on day 15. CONCLUSION: These findings suggest that the Fas and Fas-L apoptotic pathway is active during the acute phase of the viral infection and that it becomes inactive by day 15, paralleling the hematologic recovery.