T locus shows no evidence for linkage disequilibrium or mutation in American Caucasian neural tube defect families.

We investigated the T locus as a candidate gene in a series of patients and families with lumbosacral myelomeningocele. Single-strand conformation polymorphism (SSCP) analysis was used to identify sequence variation in all 8 exons and in intron 7 of this locus. We found evidence of substantial polymorphism within this locus, as previously reported [Papapetrou et al., 1999, J Med Genet 36:208-213], and moderately significant evidence of linkage disequilibrium with the CacI polymorphism of exon 8. However, when the locus was considered as a whole, with all single nucleotide polymorphisms (SNPs) integrated into a haplotype, there was no evidence for linkage disequilibrium. In addition, we did not identify any new sequence variants. Thus, we conclude that the T locus is not a major locus for human NTDs in this sample.

Cardiac arrhythmias following anesthesia induction in infantile-onset Pompe disease: a case series.

BACKGROUND: Patients with infantile-onset Pompe disease suffer from marked hypertrophic cardiomyopathy and an increased risk of arrhythmia. A noncompliant left ventricle predisposes these infants to diastolic heart failure with elevated left ventricular enddiastolic pressure (LVEDP); these patients also commonly develop systolic heart failure. Given this baseline cardiac physiology, coronary perfusion pressure becomes highly sensitive to abrupt changes in diastolic blood pressure (DBP). METHODS: We retrospectively reviewed the experiences of 139 patients enrolled in clinical trials investigating the treatment of infantile-onset Pompe disease with recombinant human acid alpha-glucosidase (rhGAA). Adverse events were screened for those involving anesthesia. RESULTS: Nine patients (6%) with infantile-onset Pompe disease experienced an arrhythmia or cardiopulmonary arrest soon after the induction of general anesthesia. Of these events, propofol was involved in four arrhythmias; sevoflurane without propofol was associated with an additional two. Deaths resulting from arrhythmia appeared to correlate with left ventricular mass indices >350 g x m(-2). CONCLUSIONS: With the advent of enzyme replacement therapy (ERT) using rhGAA, and increased survivability, more infantile Pompe patients will likely present for surgical procedures. Additional care in maximizing coronary perfusion pressure and minimizing arrhythmia risk must be given. For these reasons, it is recommended that anesthesia for infantile Pompe patients specifically avoid propofol or high concentrations of sevoflurane and, instead, use an agent such as ketamine as the cornerstone for induction in order to better support coronary perfusion pressure and to avoid decreasing DBP with vasodilatory agents.