An R248C mutation of FGFR3 leading to thanatophoric dysplasia type I

Thanatophoric dysplasia (TD) is the most common form of lethal neonatal dwarfism with micromelic shortening of the limbs, macrocephaly, platyspondyly, and reduced thoracic cavity. R248C mutation in the extracellular domain of fibrobast growth factor receptor 3 (FGFR3) was common in TD type I. Two TD type I patients were examined for R248C mutation by use of restriction digestion and direct sequencing. The results showed that both patients carried R248C mutation. Because of the homogeneity of R248C mutation among different ethnic populations, all TD patients should be analysed using this PCR-based method presented in this work.

Mutation analysis of Wilson disease in Taiwan and description of six new mutations

Wilson disease is an autosomal recessive disorder of copper metabolism. Mutation screening in Wilson disease has led to the detection of at least 89 disease-specific mutations. Some mutations appear to be population specific, while others are common to many populations. In this study, 38 Taiwanese patients with Wilson disease were screened using single-strand conformation polymorphism analysis, followed by direct DNA sequencing. We found 12 different mutations, six of which were novel. All our detected mutations were found to be in eight exons. Four mutations in three loci (Arg778Gln, Arg778Leu, Gly943Asp, and Pro992Leu) accounted for about 58% of the mutant alleles we detected. Using an RNA transcriptional assay, we confirmed that both of our detected splice-site mutations resulted in exon skipping.

Multiple pterygium syndrome: report of one case

Multiple pterygium syndrome is a rare autosomal recessive disease which is characterized by multiple pterygium across the major joint and other associated anomalies. In this article, we report a male premature infant who was born with bizarre appearance: mask face with low set ear and micrognathia; pterygium of neck, antecubital, popliteal and intercrural area with four extremities flexion contracture. He was thought to be the first case report in Taiwan. Besides, we review medical literature about this disease.

Spondyloepiphyseal dysplasia congenita: report of one case

Spondyloepiphyseal dysplasia (SED) congenita is a rare disorder with autosomal dominant inheritance which demonstrates short stature since birth and displays progressive involvement of the spine and the epiphyses of long bones. We present a case of SED congenita with short stature since birth, flat midface, short neck, barrel chest with pectus carinatum, lumbar lordosis, myopia without retinal detachment, and flat, avoid-shaped vertebral bodies. Neurological examination is normal. No specific biochemical change or intellectual impairment can be discerned.

Prenatal diagnosis of dyssegmental dysplasia. A case report

BACKGROUND

Since the first use of sonography, most fetal dwarfism has been detectable prenatally. The correct differentiation of the subtype of dwarfism is difficult at times. Dyssegmental dysplasia is probably an exception to these subtypes because the vertebral disorganization and occipital encephalocele at times permits prenatal diagnosis.

CASE

A 34-year-old woman, gravida 3, para 1, elective abortion 1 for dwarfism, was referred at 27 weeks' gestation for cystic hygroma. Further sonographic findings included: cystic hygroma with massive ascites, micromelia, occipital encephalocele, spinal disorganization and hydramnios. The fetus and both parents appeared to have a normal karyotype. Later the pregnancy was terminated with vaginal delivery. The fetus had micromelia, camptomelia, cystic hygroma, a flat face, short neck, short trunk, narrow thorax with protuberant abdomen, scoliosis and clubfeet.

CONCLUSION

Sonography is effective in prenatal diagnosis of dyssegmental dysplasia. With sonography, diagnosis of dyssegmental dysplasia becomes possible as early as the first trimester.

Different race, different face: minor anomalies in Chinese newborn infants

OBJECTIVE

To define the nature and incidence of minor anomalies in Chinese newborn infants and to evaluate the validity of the hypothesis that infants with three or more minor surface anomalies will also have a major malformation.

METHODS

A total of 3,345 Chinese newborn infants were examined based on a list of 67 items of minor anomalies.

RESULTS

About 44.9% of the newborn infants had at least one minor anomaly that was unrelated to gender, maternal age, or gestational age, but significantly associated with fetal presentation. Breech-presented newborn infants had double the risk of minor anomalies. Simian crease, upward slant and frontal bossing could be considered normal variants for Chinese newborn infants, because the incidence of each was higher than 4%.

CONCLUSIONS

Although some studies have shown that approximately 90% of infants having three or more minor anomalies are associated with a major malformation, we found only a 10.1% predictive value based on this study. Nevertheless, we suggest that infants with three or more minor anomalies be carefully evaluated for the possibility of major malformation in order to provide early management.

Molecular diagnosis of Apert syndrome in Chinese patients

Apert syndrome is a clinically distinct condition characterized by craniosynostosis and severe syndactyly of the hands and the feet. Apert syndrome results from either of two specific nucleotide substitutions, both C-to-G transversions, in the fibroblast growth factor receptor 2 (FGFR2) gene. To determine if Chinese Apert syndrome patients carry the same mutations, fifteen unrelated Apert syndrome patients and a fetus from a mother with Apert syndrome were studied by the use of restriction analysis and direct sequencing. The results demonstrated that 13 had the Ser252Trp mutation and 2 had the Pro253Arg mutation. Prenatal diagnosis of the fetus was successfully made.

Molecular diagnosis of patients with beta-thalassemia major in central Taiwan by amplified created restriction site analysis

beta-Thalassemia, a hematologic disorder characterized by the deficiency or the absence of beta-globin production, is the most widespread inherited disorder in the world; it is also common in Taiwan. We studied 38 patients in central Taiwan with beta-thalassemia major, using amplified created restriction site analysis for detection. On analysis, six different point mutations were found among 76 chromosomes, of which 32 chromosomes (42.1%) had a C to T substitution at nucleotide 654, 30 (40%) had frameshift codons 41/42 with four nucleotides (TCTT) deletion, 7 (9.2%) had an A to T substitution at codon 17, 3 (3.9%) had frameshift codons 71/72 (insertion of A), 2 (2.6%) had an A to G substitution at position -28, and 2 (2.6%) had frame-shift codons 27/28 (insertion of C). The first two mutations accounted for 62 of the 76 beta-thalassemia mutations in this study. As to mutations in each individual with beta-thalassemia major, the incidence of compound heterozygotes of two different mutations was higher than that of homozygotes of a single mutation (60% vs 40%). Compound heterozygotes of C to T substitution at nucleotide 654 of IVS-2 and frameshift codons 41/42 with four-nucleotide deletion was the most common pattern of beta-thalassemia mutations in each individual (23.7%). Our results were unique compared with those from similar studies performed in southern China. Frequencies of beta-thalassemia mutations found in the current study were assessed and compared with frequencies found in previous studies conducted in northern and southern Taiwan.

Harlequin ichthyosis: report of one case

Harlequin ichthyosis, or harlequin fetus, is a relatively rare, severe form of congenital ichthyosis. Although the clinical features have been well described, very little is known about the pathogenesis, clinical course, appropriate treatment and prognosis of harlequin ichthyosis because most of these babies with harlequin ichthyosis die within a few weeks of life. We herein report a case of harlequin ichthyosis, which we believe is the first such case in Taiwan.

Sister chromatid exchange in Chinese newborn infants treated with phototherapy for more than five days

The frequency of sister chromatid exchange (SCE) was determined in newborn infants given phototherapy for more than five days, then determined again one year later. There were 8 healthy newborn infants and 15 icterus infants; 8 of these were treated with phototherapy for more than 5 days and the other 7 were not. In the follow-up study, 6 treated infants were evaluated. The results revealed that there was an increase in mean SCE frequency of peripheral lymphocytes after phototherapy, which reversed itself one year after treatment discontinuation. Prolonged continuous phototherapy may be responsible for the increase observed in SCEs in Chinese newborn.

Prenatal diagnosis of Apert syndrome

Apert syndrome (AS) is clinically characterized by typical facial features and symmetrical syndactyly of the digits. AS is inherited as an autosomal dominant trait. Recently, a fibroblast growth factor receptors 2 (FGFR2) mutation, either C934G or C937G, was identified in exon IIIa. Our report documents an affected mother and son in whom one of the two mutations in AS had occurred sporadically in the mother. The diagnosed of AS was based on associated abnormal physical features and on molecular genetic analysis. A C-to-G transversion at position 937 of the cDNA resulting in a proline-to-arginine substitution at codon 259 was found in the mother. In her second pregnancy, prenatal diagnosis by both restriction analysis and direct sequencing was undertaken and this showed that the female fetus had not inherited the mutation.

Myelination arrest demonstrated using magnetic resonance imaging in a child with type I GM1 gangliosidosis

An 18-month-old girl was diagnosed as having GM1 gangliosidosis, on the basis of the clinical symptoms of muscle stiffness, developmental retardation, hepatosplenomegaly, and kyphoscoliosis and a laboratory study that revealed a deficiency in the lysosomal degradative enzyme beta-galactosidase. Magnetic resonance T1-weighted images showed persistent hyperintensity in the bilateral thalami, brainstem, and deep cerebellum at 14 and 18 months of age, indicating arrest of the myelination process in these areas, and that the arrest had occurred at the newborn stage. There was no myelination in the basal ganglia and diffuse leukomalacia developed in the cerebral hemispheres. Only supportive treatment was given; the patient died at 2 years of age. Myelination arrest at the newborn stage associated with progressive leukomalacia is a possible characteristic of GM1 gangliosidosis.

Fetal alcohol syndrome with Arnold-Chiari malformation: report of one case

We report a rare case of fetal alcohol syndrome (FAS) with Arnold-Chiari malformation. The new-born had the typical facial abnormalities associated with FAS and the mother had a history of heavy drinking. CNS malformation, which is rarely seen in FAS, was also presented. The relationship between the developmental defects and maternal alcohol drinking are discussed together with a review of the literature.

Catabolic effect in premature infants with early dexamethasone treatment

To evaluate the catabolic effects of dexamethasone therapy on protein metabolism, amino acid concentrations and urinary 3-methylhistidine (3MH) were measured in 28 premature infants who were included in a double-blind controlled study using early dexamethasone therapy in the prevention of bronchopulmonary dysplasia. Fifteen infants received dexamethasone (0.5 mg/kg/day i.v.) and 13 infants received normal saline as control. Heparinized venous blood samples for amino acid analysis were obtained before the study and again at day 5 after starting the study. Urinary 3MH was measured on days 1, 3, 5, 7, 14, 21, and 28 of treatment. A substantial increase in amino acid concentrations was observed in infants receiving dexamethasone. Alanine, glutamine, citrulline, ornithine and cystine concentrations increased twofold or more. The 3MH:creatinine ratio was increased in the treated group. These metabolic effects were most likely due to an increase in protein catabolism.

Detection of congenital cytomegalovirus infection in Chinese newborn infants using polymerase chain reaction

Polymerase chain reaction (PCR) amplification was used to detect cytomegalovirus (CMV) in 1000 urine specimens from Chinese newborns for defining the incidence of congenital CMV infection in the Chinese population. The major immediate-early and the late antigen genes of CMV were amplified and detected by gel electrophoresis. There were 18 congenitally infected infants found when tests were performed with one or both primer pairs. Comparing with tissue culture, PCR of both primer sets provided a sensitivity of 94%, a specificity of 100% and a predictive value of positive result of 100%.

Sex determination in infants with ambiguous genitalia using the polymerase chain reaction of an X-Y homologous region

A polymerase chain reaction (PCR) technique applicable for sex identification is described. The technique amplifies a part of the X-Y homologous amelogenin gene in which the Y counterpart has a 189 bp deletion within one of the introns. To evaluate the value of PCR of a X-Y homologous region in sex determination, individuals with ambiguous genitalia were selected for study. By identification of the X and Y sequences based on the difference in their sizes, sex determination could be successfully made.

Typhlitis in acute childhood leukemia

Typhlitis is a necrotizing inflammation of the cecum usually found in acute leukemia patients on chemotherapy in the setting of agranulocytosis. We describe five cases of typhlitis, characterized by fever, abdominal pain, abdominal tenderness and watery diarrhea, occurring during periods of neutropenia. In 4 cases, sonography showed thickening of the cecum wall. Ultrasound appears to offer an easy noninvasive method of diagnosing this potential lethal disease. Four patients were treated successfully with broad-spectrum antibiotics and bowel rest. There was 1 death resulting from septic complication.

X-linked recessive myotubular myopathy proven by muscle biopsy

We report a baby boy, the third child of a nonconsanguineous couple, with congenital myotubular myopathy. At birth, he had generalized hypotonia and respiratory distress. On physical examination, an elongated apathetic face, high-arched palate, bilateral ptosis, funnel chest, frog-leg posture, little spontaneous movement of the limbs and areflexia were observed. A chest x-ray revealed thin ribs and clavicles. The infant died 54 days after birth despite intensive management. The mother, a healthy 32-year-old female, displayed myotubes on muscle biopsy which suggested an X-linked recessive inheritance pattern for myotubular myopathy. This report illustrates the importance of taking a detailed family history as well as a muscle biopsy in the diagnosis of X-linked recessive myotubular myopathy.

Molecular diagnosis of Gaucher disease type II

Gaucher disease is a rare autosomal recessive lysosomal storage disorder in Chinese. A mutation at nucleotide 1448C (T-to-C) of the glucocerebrosidase gene is described in type 2 Gaucher disease. This mutation creates a Bcn I site in a polymerase chain reaction (PCR) amplified fragment. This technique was applied to a Chinese infant with type 2 Gaucher disease, and homozygosity for 1448C mutation was proved. This new finding can make prenatal diagnosis and carrier detection possible in Chinese population with type 2 Gaucher disease.

Sex determination in infants with ambiguous genitalia using the polymerase chain reaction of SRY gene

It has long been known that testes arise only in the presence of a Y chromosome. The existence of a hypothetical gene, the testis-determining factor (TDF) on the Y chromosome, has therefore been postulated. SRY is the gene located in the sex-determining region of the human Y chromosome and has many of the properties expected for TDF. To evaluate the value of SRY PCR in sex determination, individuals with ambiguous genitalia were selected for study. By identification of the DNA sequence of SRY, a 609-bp fragment of PCR product, sex determination could be successfully made.

Chylous ascites: report of one case

Chylous ascites is rare if found in the pediatric age group, and is usually of unknown etiology or comes from congenital anomalies of the lymphatic system. A 3.2 kg male newborn was born at 36-week gestation by Cesarean section prompted by fetal distress. Distended abdomen was noted after birth and abdominal ultrasound revealed significant ascites. Repeated paracenteses were done to relieve the respiratory distress, and a milky ascitic fluid with specific gravity of 1.031, WBC 1.32 x 10(4)/mm3 (lymphocytes predominant), and triglycerides 812 mg/dl was noted at the third tapping after feeding with normal infant formula. The lipoprotein electrophoresis of the ascites showed great increase in proportion of chylomicron to 19.05%. Pregestimil was given, and the ascites gradually subsided. The patient was discharged on the 13th day after birth. His growth was normal at one-month follow up without recurrence of ascites.

Beemer-Langer type short rib-polydactyly syndrome: report of two cases

Two sibs who died shortly after birth had multiple congenital anomalies that included hydrops, narrow thorax, short limbs, and absence of polydactyly; therefore short rib (polydactyly) syndrome Beemer-Langer type was suggested. We report these cases and discuss the differentiation with Majewski type.