Fanconi Anemia and Ataxia Telangiectasia in Siblings who Inherited Unique Combinations of Novel FANCA and ATM Null Mutations.

A unique consanguineous family with 2 genomic instability disorders, Fanconi anemia and ataxia telangiectasia, revealed exceptional combinations of null mutations in the FANCA and ATM genes. Two siblings with Fanconi anemia had novel homozygous consecutive microdeletions (c.1361-1370delCCTCCTTTGG, c.1374delC) adjoined to upstream 65 nucleotide direct tandem repeats and deletion hotspot motifs in the FANCA gene. The sibling with ataxia telangiectasia revealed a homozygous p.Arg2993Stop (c.8977C>T) null mutation in the ATM gene. All patients were also heterozygous for the opposite mutations without any additional clinical or laboratory manifestations. Double heterozygote parents did not present any clinical symptoms suggestive of the 2 disorders.

Bone marrow mesenchymal stem cell donors with a high body mass index display elevated endoplasmic reticulum stress and are functionally impaired.

Bone marrow mesenchymal stem cells (BM-MSCs) are promising candidates for regenerative medicine purposes. The effect of obesity on the function of BM-MSCs is currently unknown. Here, we assessed how obesity affects the function of BM-MSCs and the role of endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) therein. BM-MSCs were obtained from healthy donors with a normal (<25) or high (>30) body mass index (BMI). High-BMI BM-MSCs displayed severely impaired osteogenic and diminished adipogenic differentiation, decreased proliferation rates, increased senescence, and elevated expression of ER stress-related genes ATF4 and CHOP. Suppression of ER stress using tauroursodeoxycholic acid (TUDCA) and 4-phenylbutyrate (4-PBA) resulted in partial recovery of osteogenic differentiation capacity, with a significant increase in the expression of ALPL and improvement in the UPR. These data indicate that BMI is important during the selection of BM-MSC donors for regenerative medicine purposes and that application of high-BMI BM-MSCs with TUDCA or 4-PBA may improve stem cell function. However, whether this improvement can be translated into an in vivo clinical advantage remains to be assessed.

The clinical and laboratory evaluation of familial hemophagocytic lymphohistiocytosis and the importance of hepatic and spinal cord involvement: a single center experience.

Familial hemophagocytic lymphohistiocytosis is an autosomal recessive, life-threatening condition characterized by defective immune response. A retrospective analysis was performed on 57 patients diagnosed with familial hemophagocytic lymphohistiocytosis at Hacettepe University Pediatric Hematology Department, Ankara, Turkey. Mutation analysis was performed on 37 patients, and of these: 11 had UNC13D, 10 had PRF1 and 3 had STX11 gene mutation. Of these patients, 44% were found to have central nervous system involvement on admission and spinal cord involvement was also seen in 5 patients. Remission was achieved in 24 patients with the treatment, in a median time of 76 days (min-max: 15-705 days). Time to remission was prolonged 3.1 times in patients with a ferritin level 1500 mg/dL or more. When patients were grouped according to age [Group 1 (≤ 2 years), Group 2 (>2 years)]; patients in Group 1 had higher ferritin and aspartate aminotransferase levels but lower fibrinogen levels. The 5-year survival rate was also lower in Group 1. When patients in Group 1 were divided into two sub-groups according to hepatic involvement, the 5-year survival rate of patients who had hepatic involvement was significantly lower than those patients without hepatic involvement (0.7%, 27%, respectively) (P=0.002). The 5-year survival rate of patients who underwent hematopoietic stem cell transplantation was significantly higher than the patients who didn't (44%, 16%, respectively) (P=0.02). In conclusion, age two years and under, ferritin level above 1500 mg/dL, spinal cord or hepatic involvement should be considered as poor prognostic factors in familial hemophagocytic lymphohistiocytosis.

Survey of Hfe Gene C282Y Mutation in Turkish Beta-Thalassemia Patients and Healthy Population: A Preliminary Study.

OBJECTIVE: This study was planned in order to determine the effect of C282Y mutation in development of secondary hemochromatosis in beta-thalassemia patients and to determine the prevalence and allele frequency of this mutation in a healthy control group. MATERIALS AND METHODS: Eighty-seven children and young adults (46 males and 41 females; mean age: 15.6±6.1 years, range: 3-30 years) with beta-thalassemia major (BTM) and 13 beta-thalassemia intermedia (BTI) patients (6 males and 7 females; mean age: 19.6±3.5 years, range: 13-26 years) were included in the study. The control group comprised 100 healthy blood donors. RESULTS: Neither heterozygous nor homozygous HFE gene C282Y mutation was detected in patients with BTM or BTI, or in control group. CONCLUSION: The C282Y mutation, which is supposed to be responsible for the majority of hereditary hemochromatosis, was not found to have a role in the development of hemochromatosis in beta-thalassemia patients and was not detected in a healthy Turkish population. However, research on larger cohorts of individuals is required in order to determine the exact prevalence of the HFE gene mutation in Turkish populations from diverse ethnic origins and whether it would have an impact on iron loading in thalassemic populations.

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.

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.

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.

Leptin promoter G-2548A genotypes and associated serum leptin levels in childhood acute leukemia at diagnosis and under high-dose steroid therapy.

Genotype/allele distributions of leptin promoter G-2548A polymorphism, serum leptin and insulin levels and body weight were not significantly different between 72 children (39 male/33 female; age range 1.08-16, median 6 years) with acute leukemia (56 acute lymphoblastic leukemia [ALL]/16 acute non-lymphoblastic leukemia [ANLL]) at diagnosis and 70 age- and sex-matched controls (p > 0.05). The - 2548GG genotype was associated with the highest leptin levels in controls and patients with acute leukemia after 7-day high-dose methylprednisolone (HDMP) therapy (p < 0.05), while no significant association of genotype with leptin levels was detected in patients at diagnosis (p > 0.05). One-week HDMP therapy in patients carrying the - 2548G allele caused a significant increase in leptin levels and body weight (p < 0.001), whereas increases in those carrying the - 2548AA genotype were insignificant (p > 0.05). Decreases in white blood cell counts of patients after therapy were insignificant in - 2548GG (p > 0.05) yet significant in - 2548GA and - 2548AA (p < 0.05) genotypes. These results revealed no association of leptin genotype with the etiology of childhood acute leukemia but a possible association with leptin levels and effects of HDMP therapy.

Spinal cord involvement in a child with familial hemophagocytic lymphohistiocytosis.

The involvement of the central nervous system (CNS) in familial hemophagocytic lymphohistiocytosis (FHL) has known to be limited to the brain, brain stem, and cerebellum. Herein, we report an 11-year-old boy who presented with neurological symptoms and was diagnosed as FHL by molecular diagnosis. The hemophagocytic lesions in the CNS were shown to extend to the thoracal level of spinal cord which completely disappeared after the completion of hemophagocytic lymphohistiocytosis-2004 protocol.

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.

Hemophagocytic syndrome in a child with severe Crohn's disease and familial Mediterranean fever.

Hemophagocytic lymphohistiocytosis (HLH) is a rare, potentially fatal, severe condition of hyperinflammation caused by the uncontrolled proliferation of activated lymphocytes and histiocytes secreting high amounts of inflammatory cytokines. Here we report a fatal hemophagocytic syndrome in a 11-year-old boy with a diagnosis of both Crohn's disease receiving immunosuppressive therapy and familial Mediterranean fever. It is important to evaluate the patients with inflammatory bowel disease receiving immunosuppressive therapy presenting with unexplained fever, cytopenia, progression of organomegaly and biochemical changes for the investigation of HLH for diagnosis and treatment.

Assessment of clinical and laboratory presentations of familial hemophagocytic lymphohistiocytosis patients with homozygous W374X mutation.

Homozygous W374X mutation was identified in unrelated 13 patients (6M/7F) from consanguineous families, 62% of which had history of deceased sibling. Haplotype analysis provided evidence for the probable existence of a founder effect. Age at disease onset ranged from 1 day to 5.5 months (median 2 months). Hepatic dysfunction was observed in 69%, ascite 62%, hypertriglyceridemia 77%, each hyperferritinemia and hypofibrinogenemia 85%, CNS involvement 46% of patients while birth weights were in normal range. Those with very high ferritin (>20,000ng/ml) had extremely low fibrinogen levels. Two-thirds of patients receiving HLH protocol died within 20 days of therapy.

Central nervous system involvement in Turkish children with primary hemophagocytic lymphohistiocytosis.

This report mainly presents the clinical and laboratory findings in a group of 15 primary hemophagocytic lymphohistiocytosis patients with central nervous system involvement (group 1) and compares some of the findings with those of 13 hemophagocytic lymphohistiocytosis patients without central nervous system involvement (group 2). Statistical analysis showed that age and sodium level at diagnosis were significantly higher while alanine aminotransferase and bilirubin levels were significantly lower in group 1 than group 2 (P < .05). There were no statistically significant differences between the 2 groups in the other clinical, laboratory, and overall survival parameters. Three patients in group 1 initially had central nervous system involvement in the absence of systemic findings, which led to the initial misdiagnosis of these patients as central nervous system disorders other than hemophagocytic lymphohistiocytosis.

Clinical and molecular aspects of Turkish familial hemophagocytic lymphohistiocytosis patients with perforin mutations.

The aim of this study was to elucidate the pathologic sequence changes and associated clinical phenotypes in 9 new patients showing homozygosity for perforin gene among a total of 37 (24%) Turkish FHL families studied by linkage analysis. These 9 unrelated patients (5M/4F) were coming from consanguineous families and their presentation ages of systemic symptoms were ranged from birth to 15 years. Direct sequencing of coding exons of the perforin gene led to the identification of five different homozygous alterations. The nonsense W374X mutation was identified in three patients while four different missense mutations namely G149S, V50M, A91V and novel A523D were detected in the rest six patients.

Significance of fetal hemoglobin values in detection of heterozygotes in fanconi anemia: reevaluation of fetal hemoglobin values by a sensitive method.

Fanconi anemia (FA) is a genetically very heterogeneous disease making routine detection of carriers quite difficult by molecular analysis. Finding alternative method has vital importance especially in populations where prevalence of the disease is quite high because of consanguineous marriages. The aim of this study was to find a considerably reliable parameter to detect FA carriers by methods other than molecular analysis. The subjects of this study were 66 parents of children with FA and 40 age and sex compatible individuals from the normal healthy population. An index family with a known mutation was also included as an evidence for verification of the results. The mean fetal hemoglobin (HbF) values (0.81%+/-0.72%) of FA heterozygotes studied by high-performance liquid chromatography was significantly higher than that (0.37%+/-0.32%) of the control group (P<0.001). Additionally, there was a positive correlation between the HbF value of the children (mean: 4.50+/-1.59) and the parents (mean: 0.81+/-0.72) (r: 0.698, P=0.01). No significant difference was detected between the hemoglobin, hematocrit, red blood cell count, mean corpuscular volume, red cell distribution width, white blood cell count, absolute neutrophil count, and platelet counts of the study and control groups. The results of this study suggest that the HbF values may be used as a marker to predict carriers in the family members of a child with FA when definitive diagnosis by molecular analysis is not possible.

Plasminogen activator inhibitor-1 4G4G genotype is associated with myocardial infarction but not with stable coronary artery disease.

BACKGROUND: A case control study was conducted to test the hypothesis that plasminogen activator inhibitor type-1 (PAI-1) 4G/5G gene polymorphism confers an increased risk for myocardial infarction (MI) in patients with known coronary atherosclerosis. METHODS: One hundred fifty-six consecutive patients who presented with acute MI and 111 stable coronary artery disease (SCAD) patients with documented critical coronary artery stenoses were prospectively enrolled. PAI-1 4G/5G gene polymorphism and conventional atherosclerotic risk factors were studied in all patients. PAI-1 4G/5G gene polymorphism was studied in another 281 healthy blood bank donors. RESULTS: The frequency 4G4G genotype was significantly higher in the MI group as compared to SCAD group (32.7% vs. 15.3%, P = 0.001) while it was not statistically significant between MI and healthy control groups (32.7% vs. 26.0%, P = 0.136). Comparing with healthy controls SCAD group had significantly lower frequency of 4G4G genotype (P = 0.024). In comparison with SCAD group PAI-1 4G/4G genotype, male sex and smoking habits favored to MI in univariate analysis with a P value of less than 0.2. These variables were included in multivariate regression model to estimate the associated risk for MI. PAI-1 4G/4G genotype was the only independent variable (OR 2.67, 95%CI 1.43-4.96, P = 0.002) associated with MI in this regression model. Comparing with healthy control group 4G4G genotype was not associated with MI (OR 1.38, 95%CI 0.90-2.12). However, presence of 4G4G genotype had a protective effect against development of SCAD (OR 0.52, 96%CI 0.29-0.92). CONCLUSION: Compared to patients with critical coronary stenoses, PAI-1 4G/4G genotype was found to be an independent predictor for development of MI in this population. PAI-1 4G4G genotype have a protective effect against development of high grade stable coronary stenoses.

Significance of factor V, prothrombin, MTHFR, and PAI-1 genotypes in childhood cerebral thrombosis.

The aim of this study was to evaluate the significance of factor V (FV) G1691A, prothrombin G20210A, methylenetetrahydrofolate reductase (MTHFR) C677T, and plasminogen activator inhibitor-1 (PAI-1) 4G/5G genotypes in development of childhood cerebral thrombosis (CT). A total of 113 Turkish children with CT were studied and compared with the control group. The carrier frequency of the factor V G1691A mutation was found to be significantly higher in the patient group (17.7%) than controls (7.4%). The presence of this genotype was associated with a 2.7-fold increased risk of developing CT (95% confidence interval [CI], 1.0-7.0). The prevalence of prothrombin G20210A mutation in 110 patients (4.5%) was insignificantly higher than controls (2.3%) (odds ratio, 2.0; 95% CI, 0.4-10.7). A statistically significant increase in the frequency of homozygous MTHFR C677T genotype was observed in 62 patients (11.3%) compared to controls (4.3%), and this genotype was associated with 2.8-fold increased CT risk (95% CI, 1.0-8.0). The incidence of PAI-1 4G/4G genotype in 65 patients (21.5%) was slightly lower than that of controls (26.0%), but the differences did not reach statistical significance (odds ratio, 0.8; 95% CI, 0.4-1.5). The results of this study suggested that factor V G1691A and MTHFR C677T genotypes may be associated with an increased risk of developing CT in Turkish children.

Analysis of some clinical and laboratory aspects of adolescent patients with thrombosis.

A total of 360 pediatric patients aged 1 month to 18 years were diagnosed as having thrombosis between January 1998 and April 2003. Of these patients, those aged 11-18 years (n=131) were regarded as adolescents and the rest as children. The proportion of adolescents in the whole group excluding the neonates was 36%. The peak age of diagnosis in adolescents was 11-14 years, comprising 58% of all thrombotic events in adolescents. In 73% of the adolescents, there was at least one risk factor. The four most common underlying disorders were infection, malignancy, connective tissue and cardiac disorders, in decreasing order of frequency. In children, on the other hand, infection was followed by congenital heart disease, malignancy and liver disease. Three common types of thrombosis in adolescents were deep venous thrombosis, cerebro-vascular events and portal venous thrombosis, while cerebro-vascular events were the most common in children. The frequency of factor V G1691A mutation in the adolescents (22.1%) was significantly higher than that found in a group of healthy controls (7.4%) and this mutation was associated with a 3.6-fold increase in the risk of developing thrombosis (95% confidence interval, 1.4-9.0). The carrier frequency of prothrombin G20210A mutation (3.1%) in adolescents did not differ significantly from that of the healthy population (2.3%) and no association was observed between this mutation and a risk of developing thrombosis in this group (odds ratio, 1.3; 95% confidence interval, 0.2-7.5). The rate of recurrent thrombosis was 6%.

Clinical and laboratory evaluation of Turkish children with thrombosis for homozygous factor V G1691A mutation.

Factor V (FV) G1691A mutation, in a heterozygous state, is one of the most common inherited risk factors for development of thrombosis. However, the clinical manifestations of homozygosity for the FV G1691A mutation in children is largely unknown because of the limited number of studies reported. The purpose of this study was to evaluate the clinical manifestations and laboratory findings of children with thrombosis who were homozygous for this mutation. Ten patients (four male/six female; mean age, 4.5 years; age range, 1-13 years) who were found to be homozygous for the FV G1691A mutation among 360 consecutive children with thrombosis (2.8%) were the subjects of this study. Six of the 10 patients had venous thrombosis, two had purpura fulminans, one had diffuse skin ecchymosis and one had arterial thrombosis. No history of thrombosis was present in their family members. Seven of the 10 children were under the age of 5 years. One or more additional risk factors (infection, protein S and protein C deficiencies, elevated factor VIII, etc.) were also present in nine of these patients. None of these patients had prothrombin G20210A mutation but one patient had risk-associated plasminogen activator inhibitor-1 gene 4G/4G genotype. These findings suggest that, in the presence of other underlying risk factors, homozygosity for FV G1691A mutation may lead to development of thrombosis at a very young age.