Maternal isodisomy for chromosome 2p causing severe congenital hypothyroidism.

Severe congenital hypothyroidism (CH) due to a total iodide organification defect (TIOD) is usually due to mutations in the thyroid peroxidase (TPO) gene located at chromosome 2p25. A homozygous deletion [DeltaT2512 (codon 808)] in exon 14 was identified in a patient with classical TIOD. The transmission pattern of the TPO gene in this family was anomalous; the mother was heterozygous for the deletion; and the mutation was absent in the father. Polymorphic short tandem repeat (STR) markers confirmed paternity and demonstrated on chromosome 2 that the propositus was homozygous for most markers on chromosome 2p and that these were identical to one of the maternal 2p homologs. A normal karyotype was found in the propositus, his parents and sister. We conclude that the homozygosity in the patient is due to partial maternal isodisomy of the short arm of chromosome 2, carrying a defective TPO gene. The patient, born small for gestational age, develops and grows well and appears healthy (while being treated with thyroxine) and has a normal phenotype except for a unilateral preauricular skin tag. This shows that partial maternal isodisomy for chromosome 2p (2pter - 2p12) is compatible with a minimal influence on normal development.

Myopathology in patients with a Noonan phenotype.

Two patients with a Noonan phenotype and progressive hypertrophic obstructive cardiomyopathy are described, in whom abnormal histopathological changes in striated musculature were detected. In both patients an increased density of muscle spindles was found at biopsy. The significance of an increased density of muscle spindles in patients with Noonan phenotype can only be speculated. The question is raised of whether these changes are a distinct feature within the spectrum of patients with Noonan phenotype.

Oculoauriculovertebral spectrum and cerebral anomalies.

We report on three Dutch children with a clinical diagnosis of oculoauriculovertebral spectrum (OAVS) and hydrocephalus. The clinical features are compared to 15 published cases of OAVS and hydrocephalus. Several other cerebral abnormalities were present in the whole group. About half of the cases had cleft lip/palate, anophthalmia/microphthalmia, or a cardiac defect. Mental retardation was found in five of the surviving 11 patients and early death occurred in one-third. We compared the cases with OAVS and hydrocephalus with published reports of OAVS and other cerebral anomalies and found no significant clinical differences. However, the clinical characteristics were clearly more severely expressed than generally found in patients with OAVS. Children with OAVS and more severe clinical features, especially anophthalmia/microphthalmia and cleft lip/palate, seem to be at an increased risk for cerebral malformations and for mental retardation.

Fabrication and characterization of an asymmetric polyurethane membrane for use as a wound dressing.

To prevent wound dehydration and bacterial penetration, a wound dressing should be occlusive, but on the other hand it should also be permeable for wound exudate to prevent bullae formation. To meet these requirements a new type of polyurethane wound dressing which consists of a microporous top layer (pore size less than 0.7 mum) supported by a sublayer with a highly porous sponge-like structure containing micropores (pore size less than 10 mum) as well as macropores (pore size: 50-100 mum) was designed. The pores of both layers are interconnected and form a continuous structure in the membrane. Membranes according to this design were prepared either by means of a two-step or by means of a one-step casting process. Both fabrication methods are based on phase inversion techniques. Asymmetric polyurethane Biomer membranes prepared by the two-step casting process were tested in vivo as full thickness skin substitutes using guinea pigs. Neither wound dehydration nor infections were observed while the drainage capacity of the wound dressing was effective in preventing bullae formation. Furthermore the wound dressing remained firmly adhered to the wound surface during the whole process of wound healing. In contrast to all other commercial wound dressings currently available the polyurethane wound dressing applied on excised clean wounds did not need to be replaced during healing but could be left on the wound until full regeneration of the skin had taken place after which it was spontaneously repelled.

[The TINU syndrome in children (tubular interstitial nephritis with uveitis)]. / Het TINU-syndroom bij kinderen.

Acute tubulo interstitial nephritis accompanied by uveitis is identified as TINU syndrome. The TINU syndrome is isolated from other forms of tubulo interstitial nephritis by the particular symptomatology and course: the nephropathy is almost always reversible, the uveitis tends towards relapses. The histopathologic findings are compatible with disturbance of cellular immunity, but the exact etiology is still unknown. In general, the outcome is favourable, but follow up, at least as long as there are signs of nephropathy, is necessary.

[The yield of autopsies in a pediatric practice]. / Het rendement van obducties in een pediatrische praktijk.

The yield of autopsies in a paediatric population. A retrospective analysis is presented of 91 autopsies on children, who died during the period January 1975 and December 1984 in St. Joseph Ziekenhuis, Eindhoven. In 21% of the cases (newborns 23% and older children 13%) the autopsy provided the definitive explanation for the cause of death. In 43% of the cases unexpected findings were obtained during autopsy. In 12% of the cases autopsy could not substantiate a suspected diagnosis and in 12% of the cases the findings at the autopsy influenced genetic counseling. This high rate of return stresses the importance of autopsy as a mean to improve the quality of medical care in a paediatric population.

Rubinstein-Taybi syndrome in a mother and son.

The Rubinstein-Taybi syndrome is a condition characterized by mental retardation, typical facial changes and broad thumbs and big toes. The cause is unknown; almost all cases are sporadic. We describe a mother and son with Rubinstein-Taybi syndrome. Literature search documented at least 413 cases with 558 sibs. An affected offspring has occurred at least twice, possibly six times. In 45 yet undescribed Dutch cases no recurrence was found in 94 sibs. A submicroscopic chromosome deletion seems the most probable explanation, but other alternatives may be possible.

[Hereditary onycho-osteodysplasia (HOOD)]. / De hereditaire onycho-osteo-dysplasie (HOOD).

Hereditary onycho-osteodysplasia (HOOD) is an autosomal dominant condition, characterized by dysplasia of the nails and joints and extra bone formation at the os ilium. Nephropathy occurs in some families with HOOD. We discuss a patient's history and the results of the study of her family. The incidence of all important features of this syndrome is given. Finally, some methods of treatment and genetic counseling are discussed.

[The importance of pressure registration in mask-balloon ventilation]. / Het belang van drukregistratie bij masker-ballon beademing.

In positive pressure hand ventilation appropriate ventilatory pressures are essential for effectiveness and safety of treatment. Workers in a Neonatal Intensive Care Unit were asked to ventilate an imaginary patient. A diaphragm-manometer was used for measurements. This manometer was only visible to the investigator. Peak inspiratory pressure (PIP) and peak end expiratory pressure (PEEP) were recorded. Rather great differences in administered PIP were observed. Unintentionally, PEEP was given in many cases. It is concluded, that in positive pressure hand ventilation pressures should be monitored by measurement.

[An intrapartal silent oscillation type in fetal Wolff-Parkinson-White syndrome]. / Ein intrapartaler silenter Oszillationstyp bei fetalem Wolff-Parkinson-White-Syndrom.

A discrepancy between auscultatory findings and the cardiotachogram was caused by technical limits of the cardiotocograph. The neonatal ECG showed a Wolff-Parkinson-White pattern with severe tachycardia. Some aspects of perinatal care in serious fetal and neonatal tachycardia are discussed.

Connatal Pelizaeus-Merzbacher disease with congenital stridor in two maternal cousins.

Two maternal cousins are described with the connatal form of Pelizaeus-Merzbacher Disease (PMD) and congenital stridor. Study of brain biopsy material confirms the diagnosis of PMD. The neuropathological findings are suggestive for the transitional form of this disease. Quantitative morphology gives support to the hypothesis that PMD is a disturbance in maturation of neurons and in myelin formation rather than an active degenerative process. The hereditary transmission is most consistent with a sex-linked recessive pattern. Different X-linked signs seem combined in the presented cases.

A case of focal dermal hypoplasia (Goltz syndrome) with some new aspects.

A case of Focal Dermal Hypoplasia (Goltz syndrome), diagnosed at birth, is reported. Some findings not formerly described (hemimelia, schizis of the palatum molle and the absence of one umbilical artery) are reported. Normal findings in chromosome studies with banding techniques are discussed.