Hans-Gerd Lenard

Hearing loss in facioscapulohumeral dystrophy

Bilateral sloping high frequency hearing loss of 20–90 dB was found in six out of ten patients with infantile or adolescent onset FSHD. In all cases the basic defect could be traced to the cochlea. The outer hair cells of the basal turn are predominantly affected. In 20 patients with various other forms of muscular dystrophy or neuromuscular disorders with an FSH distribution, no sensorineural hearing loss was found. Myopathology of FSHD patients extended from mild to severe, often showing inflammatory infiltrates and type I fibre atrophy, without unequivocal differences between the two groups with and without hearing loss. It is concluded that cochlear dysfunction is a specific and frequenct phenomenon of early onset FSHD.

Long-term culture and characterization of human neurofibroma-derived Schwann cells.

Neurofibromas are benign tumors arising from the peripheral nerve sheath and are a typical finding in neurofibromatosis type 1 (NF1). Schwann cells are the predominant cell type in neurofibromas and thus are supposed to play a major role in the pathogenesis of these tumors. It is not known, however, if NF1 mutations in Schwann cells result in an altered phenotype that subsequently leads to tumor formation. To characterize the biological properties of neurofibroma‐derived Schwann cells we developed cell culture techniques that enabled us to isolate Schwann cells from neurofibromas and grow them in vitro for several weeks without significant fibroblast contamination. Neurofibroma‐derived Schwann cells were characterized by altered morphology, heterogeneous growth behavior, and increased expression of the P0 antigen while several other features of normal human Schwann cells were retained. We conclude that neurofibroma‐derived Schwann cells exhibit a distinct phenotype in vitro but that the observed abnormalities by themselves are insufficient to explain neurofibroma formation. Application of our improved culture conditions makes neurofibroma‐derived Schwann cells readily available for further studies to define their role in tumorigenesis in neurofibromatosis type 1. J. Neurosci. Res. 61:524–532, 2000.

Tourniquet syndrome—accident or abuse?

The tourniquet syndrome describes severe strangulations of appendages by hair, cotton or similar material mainly observed in young infants. The painful swellings of digits or external genitals are surgical emergencies because the strangulation can cause ischaemia and tissue necrosis. More than 100 cases of the tourniquet syndrome have been reported in most of which the aetiology was unclear. We have treated five patients with a tourniquet syndrome. Four of them presented with strangulations of one or more toes by hair or threads and one girl was diagnosed with a clitoral tourniquet syndrome. In each case the strangulating material could be removed in time avoiding permanent damage. The lack of any reasonable explanation and the meticulous wrapping made a non-accidental course very likely. Due to the lack of convincing explanations in our cases as well as in most of those described in the literature, we suggest that the tourniquet syndrome is often the result of child abuse, an aetiology overlooked for decades. Conclusion:the tourniquet syndrome in childhood should be included in the list of possible forms of child abuse and should be considered as a differential diagnosis until another aetiology can be convincingly proven.

Pallister-Killian syndrome in older children and adolescents

The Pallister-Killian syndrome is caused by a mosaic tetrasomy of the short arm of chromosome 12. Although analysis of peripheral blood lymphocytes usually reveals a normal karyotype, an isochromosome 12p mosaicism is detectable in fibroblast cultures; therefore, in this rare chromosomal aberration, clinical recognition is crucial for appropriate cytogenetic investigations. The phenotype of younger children has already been well documented. During childhood and adolescence, however, the phenotype changes markedly. The disorder in older children and young adults is characterized by a coarse and flat facies, macroglossia prognathia, everted lower lip, and severe psychomotor retardation with muscular hypertonia and contractures. Two severely mentally retarded patients are reported whose diagnoses were confirmed by fibroblast cultures at ages 16 and 21 years.

Mypopathy in Williams-Beuren syndrome

Williams-Beuren syndrome (WBS) is a disorder of unknown aetiology. The classical features of the syndrome include a typical (‘elfin’) facies, mental retardation and heart defects. Myopathy has not so far been part of the spectrum of WBS. We studied six patients with WBS aged 3–25 years, five of whom showed clinical and morphological evidence of myopathy. The clinical manifestations of myopathy included hypotonia in infancy, walking delay, joint contractures, scoliosis, and increased exhaustion on exertion. These symptoms were present in variable expression but part of a typical postural pattern. Examination of muscle biopsies showed lipid storage in four patients and increased variability of fibre size in three. In one patient a muscle biopsy gave normal results. Biochemical investigation in four patients with morphological evidence of lipid storage in muscle revealed muscle carnitine deficiency in three. In addition, enzyme activities of fatty acid β-oxidation were low in one of two specimens tested. It is concluded that a clinically relevant myopathy is part of the multi-system manifestation of WBS and a clinical trial of carnitine supplementation is justified.

The Floating-Harbor syndrome

We describe the seventh patient with the Floating-Harbor syndrome. Similar to previous cases in the literature this girl presented with proportionate intrauterine and postnatal growth retardation, normocephaly, triangular face with bulbous nose, long eyelashes, short upper lip, small vermilion border of upper lip, dorsally rotated ears, deep nuchal hair line, hirsutism, and clinodactyly of little fingers. She exhibited mental retardation and retarded speech development. Clinical symptoms and differential diagnosis of this rare syndrome are briefly discussed.

Report of a deletion 11 (qter→q23.3) and short review of the literature

A male child is described with short stature, mental retardation and unusual facial appearance. Cytogenetic analysis revealed a partial deletion of the long arm of chromosome 11: 46,XY,del (11)(qter→q23.3:). A short review of previously reported cases of del 11q is presented. A comparison of the main clinical characteristics and the extent of the 11q deletion is given.

Haemolytic anaemia in association with Escherichia coli O157 infection in two sisters.

Two sisters, 2 and 5 years of age, suffered from acute haemolytic anaemia occurring after gastroenteritis withEscherichia coli 0157. One patient developed clinical signs of severe and acute intravascular haemolytis and sepsis. She received transfusion and antibiotic therapy. The second patient presented with mild to moderate haemolytic symptoms only. None of them developed renal impairment. In serum of both children, elevated titres of short-lived agglutinins were demonstrated in the indirect haemagglutination assay consisting of sheep erythrocytes coated with lipopolysaccharide fromE. coli 0157. By immunoblot analysis IgM antibodies against the 0157 lipopolysaccharide were demonstrated in the acute phase sera but not in follow up sera taken 2 months after disease. On erythrocyte membranes, adsorption of microbial antigens was detected by use of a pool-immunoglobulin fluorescence test. The immunological status of both patients was normal. Complete recovery from haemolytic disease was observed without further therapy. Microbial antigens attached to the cell surface were assumed to be the pathophysiological cause ofE. coli 0157 associated haemolytic anaemia in two siblings.

Erkrankungen im Kindesalter

Bei Entbindungen ohne pra- oder perinatale Risikofaktoren sind in der Regel fur das Neugeborene keine Probleme zu erwarten. Trotzdem muss der verantwortliche Arzt einer geburtshilflichen Abteilung dafur Sorge tragen, dass bei jeder Geburt eine Person sofort erreichbar sein kann, die mit den Grundregeln der Reanimation von Neugeborenen vertraut ist. Ein neonatologisch versierter Padiater sollte bei Risikoentbindungen zugegen sein. Notwendige Ausrustungen (Reanimationsplatz mit Warmestrahler, Absaugvorrichtung, Sauerstoff, Beatmungsbeutel, Laryngoskop, Tuben etc.) mussen vorhanden sein und ihre Funktion regelmasig uberpruft werden. Hochrisikoentbindungen sollten in einem Perinatalzentrum erfolgen.

Neun ausgewählte Fälle einer Therapieverweigerung

Schon kurz nach der Geburt bemerkten die Eltern, das bei dem Madchen der rechte Fus nicht aktiv bewegt wird. Im Alter von 4 Monaten wurde durch facharztliche Untersuchung eine Nervenlahmung in dem rechten Bein diagnostiziert, bei sonst altersentsprechender Entwicklung. Im 5. Lebensmonat stillt die Mutter ab und bemerkt Probleme bei der Stuhlentleerung der Tochter. Kurze Zeit spater treten Entleerungsstorungen seitens der Blase hinzu, so das die Mutter durch Druck auf den Bauch bzw. Microclistire die Entleerung von Blase und Darm unterstutzen mus. Wegen der fortschreitenden Symptome wird im Alter von 14 Monaten ein Kernspintomogramm des Bauchraumes durchgefuhrt, bei der sich ein Tumor im Bauchraum zeigt, der in den Wirbelsaulenkanal hineingewachsen ist und auf das Ruckenmark druckt. Dieser Tumor mus als verantwortlich angesehen werden fur die Lahmungserscheinungen im Bereich der unteren Korperhalfte: Inzwischen ist eine schlaffe, aber inkomplette Lahmung an beiden Beinen feststellbar. Der Beckenboden ist vollstandig gelahmt.