Infant methylenetetrahydrofolate reductase 677TT genotype is a risk factor for congenital heart disease.

OBJECTIVE: Recently, an association between the homozygous C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene in infants with congenital neural tube defects or congenital oral clefts has been shown. However, no data are available so far with respect to the MTHFR 677TT genotype in children with underlying structural congenital heart disease (CHD). METHODS: We investigated the MTHFR genotype in 114 Caucasian CHD patients aged newborn to 16 years (median 0.6 years; 53% male) and in 228 age- and sex-matched healthy controls. RESULTS: In childhood patients with CHD the homozygous MTHFR 677TT genotype was found in 21 out of 114 subjects (18.4%) compared with 21 out of 228 controls (9.2%; odds ratio (OR) 2.2, 95%-confidence interval (CI) 1.2-4.3; P=0.027). In patients with pulmonary valve stenosis, hypoplastic left heart syndrome, coarctation of the aorta, aortic valve stenosis or subaortic stenosis the frequency of the TT genotype varied between 38 and 67% with corresponding ORs from 6.1 (CI, 1.4-27.5; P=0.034) to 20.4 (CI, 1.8-235.0; P=0.025), whereas in other structural CHD the frequency of this genotype was not significantly different from the controls. CONCLUSIONS: With the present study we can show for the first time that the embryonal MTHFR 677TT genotype is significantly associated with the development of structural congenital heart malformations during early pregnancy. It remains to be clarified, whether this genotype is at least a risk marker or a risk factor for structural congenital heart malformations.

Genetic risk factors of thrombophilia in ischaemic childhood stroke of cardiac origin. A prospective ESPED survey.

UNLABELLED: Ischaemic stroke is a rare event in childhood. In approximately one-fourth of cases an underlying cardiac disease can be detected. We investigated the importance of genetic risk factors of venous thromboembolism in childhood or stroke in adulthood as risk factors for ischaemic stroke in children in a multicentre survey focusing on patients with a cardiac disease. 38 of 162 white infants and children (neonate-18 years) with ischaemic stroke were suffering from a cardiac disorder. An age-matched group of 100 children from the same geographic areas as the patients served as controls. Patients and controls were analysed for increased lipoprotein (a) levels > 30 mg/dl, for the presence of the factor V (FV) G1691A mutation, the prothrombin (PT) G20210 A variant, and deficiencies of protein C, protein S, and antithrombin. The following frequencies (patients vs. controls), odds ratios (OR) and confidence intervals (CI) of single risk factors were found: Lp(a) > 30 mg/dl (18.4% vs. 5%; OR/CI: 4.3/1.3-14.4; p = 0.03), FV G1691A (13.2% vs. 4%; OR/CI 3.63/0.92-14.3; p = 0.12) protein C type I deficiency (15.8% vs. 1%; OR/CI: 18.5/2.15-16.0; p = 0.0017), anticardiolipin antibodies (10.5% vs. 0%; p = 0.0051). No protein S or antithrombin deficiency was found. Combinations of haemostatic disorders were found in 10.5% of cases but in none of the controls (Fisher 0.005). CONCLUSION: While FV G1691A and prothrombin G20210 A mutations show no significant data in our study, lipoprotein (a) levels >30 mg/dl protein C deficiency, anticardiolipin antibodies and combined prothrombotic disorders seem to be important risk factors for manifestation of ischaemic strokes in children with underlying cardiac disorders.

Lipoprotein (a): its role in childhood thromboembolism.

PURPOSE: Elevated lipoprotein (a) [LP (a)] concentrations are independent risk factors of coronary heart disease or stroke in young adults. To clarify its role in childhood thromboembolism, Lp (a) was measured in 72 children with thromboembolism. METHODS: In addition to Lp (a), defects of the protein C anticoagulant system, antithrombin, and antiphospholipid antibodies were investigated in children with arterial (n = 36) or venous (n = 36) thrombosis. RESULTS: Enhanced Lp (a) >50 mg/dL was diagnosed in 8 out of 36 children with arterial and 5 out of 36 patients with venous thrombosis. Of the 72 children, 25 showed the factor V Leiden mutation, 10 showed protein C deficiency, 2 showed antithrombin deficiency, and 4 showed primary antiphospholipid syndrome. Three children with increased Lp (a) were heterozygous for the factor V Leiden mutation, and 1 girl showed additional protein C deficiency. CONCLUSIONS: Data of this study indicate that increased concentrations of Lp (a) play an important role in childhood thrombosis.

Multivariate evaluation of prognostic factors in localized neuroblastoma.

PURPOSE: A multitude of risk factors has been described for patients with neuroblastoma. Little is known about the mutual interrelationship of these factors and their impact on patients with localized disease only. PATIENTS AND METHODS: We investigated the possible influence of 37 variables univariately on event-free survival (EFS) in 308 consecutive patients with neuroblastoma stages I-III using Kaplan-Meier estimates. The chi 2 test was applied to detect nonrandom correlations, and the Cox's regression model was used for the multivate evaluation of identified factors. RESULTS: Seventeen factors appeared to influence EFS in stage I-III patients (p < 0.05, log-rank > 3.84), whereas 10 factors were found in the subgroup of stage III patients with midline crossing tumors (= stage III*, n = 128). The majority of univariately identified risk factors showed a nonrandom correlation to several others (p < 0.05). The multivariate analysis according to Cox selected for the patients with stages I-III the factors lactate dehydrogenase (LDH) (p = 0.0011), resectability (p = 0.0167), weight loss (p = 0.0185), tumor extension beyond midline (p = 0.0207), and age (p = 0.0233). For stage III* patients the model identified the factors LDH (p = 0.0089), weight loss (p = 0.0135), resectability (p = 0.0408), and age (p = 0.0700). The identification of these independent risk factors permitted the description of risk groups with EFS ratios after > 6 years between 22% and 96%. CONCLUSIONS: Risk estimation of high discriminating power is possible for patients with localized neuroblastoma using simple, readily available clinical data.