Molybdenum cofactor deficiency mimics cerebral palsy: differentiating factors for diagnosis

We describe an infant with molybdenum cofactor deficiency, initially diagnosed as cerebral palsy. Clinical features of molybdenum cofactor deficiency, e.g., neonatal seizures, hypertonus/hypotonus, and feeding and respiratory difficulties, resemble those of neonatal hypoxic-ischemic encephalopathy. Our patient, a 2-year-old boy, presented with spastic quadriplegia and mental retardation. He manifested intractable neonatal seizures and diffuse cerebral atrophy. When admitted with bronchitis at age 18 months, his uric acid levels in blood and urine were undetectable. A urinary sulfite test revealed positive results. Further tests revealed elevated urinary levels of xanthine, hypoxanthine, and S-sulfocystein. Sequencing of the MOCS2A gene revealed heterozygosity for c.[265T>C]?+ [266A>G], diagnosed as molybdenum cofactor deficiency type B. Neonatal seizures, progressive cerebral atrophy, and low serum levels of uric acid may provide diagnostic clues in patients with cerebral palsy of undetermined cause.     

Evaluation of pulmonary blood supply by multiplanar cine magnetic resonance imaging in patients with pulmonary atresia and severe pulmonary stenosis

The purpose of this study was to assess the capability of multiplanar cine magnetic resonance imaging (MRI) for evaluating pre- and post-operative pulmonary circulation in patients with pulmonary atresia and severe pulmonary stenosis. Seventy-three multiplanar cine MRIs were performed in 30 patients, aged 1 month to 7 years (mean age, 27 months). The morphology and size of the central pulmonary arteries (PA), source of the major aortopulmonary collateral arteries (MAPCA), patency of Blalock–Taussig (BT) shunt vessels, and the post-operative pulmonary circulation were assessed. The accuracy of cine MRI was compared with that of angiography in all patients. The PA was visualized to the first hilar branch in 21 patients, but not in 8 patients in whom the central PA was absent. On follow-up MRI, PA growth was measured, and the results showed excellent correlation with the results obtained by angiography. In 17 patients who had undergone 23 BT shunt operations, cine MRI correctly demonstrated all patient shunts and 5 of 6 stenotic lesions. Multiplanar cine MRI provided excellent detail of the peripheral PA in all patients, 7 of 8 peripheral pulmonary stenoses, 3 of 4 nonconfluent pulmonary arteries, and 2 of 3 PA obstructions. Although the sources of MAPCA were identified in 7 of 9 patients, the distal connection of the MAPCA was not detected in all patients. Seven patients were reexamined after pulmonary plasty; they exhibited normal pulmonary flow patterns. Multiplanar cine MRI provides high-resolution imaging of PA with dynamic visualization of flow and is an effective noninvasive technique for evaluating pre- and post-operative patients with pulmonary atresia and severe pulmonary stenosis.     

Measurement of layer thickness using spread width of longitudinal image in helical CT

We propose a new method to measure the thickness of very thin single layers in helical computed tomography images. This method involves using the density profile of a longitudinal image to obtain the image width. First, we examined the images of the step density distribution of block phantoms to clarify the step spread function and to decide the spread width (L) of longitudinal images. It was found that the spread width is half of a sum of the X-ray beam collimation and the table feed distance when 180 degrees linear interpolation is used. Next, we derived the density profile of a single layer by taking the density distributions of a single layer to be the composite of step density distributions of different step heights. An important relation is made clear that the image width of the longitudinal image for a single layer of thickness (D) is equal to D+2L whether the shape is symmetrical or not. From this relation the thickness can be measured by detecting the image width with a known value of the spread width of longitudinal images. In conditions of beam collimation of 1.0 mm, table feed distance of 1.0 mm, and reconstruction interval 0.5 mm, measurement accuracy of this method using the density profile of a longitudinal image is estimated to be within 0.05 mm. This method is much more effective than the conventional method using a gray level image for measuring thicknesses less than 0.6 mm. In addition, this method appears to be more consistent than the conventional method, as indicated by a lower standard deviation for figures obtained with this method than for those obtained with the conventional method. We applied this method to the measurement of the thickness of thin cortical bones.     

Identification of a novel TPM1 mutation in a family with left ventricular noncompaction and sudden death

Left ventricular noncompaction (LVNC) is a cardiomyopathy morphologically characterized by 2-layered myocardium, numerous prominent trabeculations, and deep intertrabecular recesses communicating with the left ventricular cavity. The purpose of this study was to investigate patients with LVNC for possible disease causing mutations. We screened 4 genes (TAZ, LDB3, DTNA and TPM1) in 51 patients with LVNC for mutations by polymerase chain reaction and direct DNA sequencing. A novel missense substitution in exon 1 of TPM1 (c.109A>G: p.Lys37Glu) was identified in three affected members of a family with isolated LVNC. The substitution brings about a change in amino acid charge at a highly conserved residue and could result in aberrant mRNA splicing. This variant was not identified in 200 normal control samples. Pathologic analysis of a right ventricular myocardial specimen from the proband's maternal aunt revealed endocardial and subendocardial fibrosis with prominent elastin deposition, as well as the presence of adipose tissue between muscle layers, pathologic changes that are distinct from those seen in patients with HCM or DCM. Screening of the proband and her mother for variants in other sarcomeric protein-encoding candidate genes, MYH7, MYBPC3, TNNT2, TNNI3, ACTC, MYL2, and MYL3, did not identify any other non-synonymous variants or variants in splice donor-acceptor sequences that were potentially disease causing. We conclude TPM1 is a potential candidate disease-causing gene for isolated LVNC, especially in patients experiencing sudden death.     

Effects of hepatitis B virus infection on the interferon response in immunodeficient human hepatocyte chimeric mice

Complementary DNA microarray analysis of human livers cannot exclude the influence of the immunological response. In this study, complementary DNA microarray analysis was performed under immunodeficient conditions with human hepatocyte chimeric mice, and gene expression profiles were analyzed by hepatitis B virus (HBV) infection and/or interferon treatment. The expression levels of 183 of 525 genes upregulated by interferon treatment were significantly suppressed in response to HBV infection. Suppressed genes were statistically significantly associated with the interferon signaling pathway and pattern recognition receptors in the bacteria/virus recognition pathway (P = 1.0 × 10(-8) and P = 1.2 × 10(-8), respectively). HBV infection attenuated virus recognition and interferon response in hepatocytes, which facilitated HBV escape from innate immunity.     

Ultrasound-guided needle aspiration of epidural hematoma in a neonate after vacuum-assisted delivery

Introduction  

Epidural hematoma (EDH) is a rare complication of vacuum-assisted delivery in neonates. Although the standard treatment of EDH is surgical evacuation via craniotomy, it is an invasive procedure in neonates, and less invasive methods may be favored for hematoma evacuation.