Horst von der Hardt

Detection of more than 50 different CFTR mutations in a large group of German cystic fibrosis patients.

We have conducted a comprehensive study of the molecular basis of cystic fibrosis (CF) in 350 German CF patients. A screening approach based on single-strand conformation analysis and direct sequencing of genomic polymerase chain reaction products has allowed us to detect the molecular defects on 95.4% of the CF chromosomes within the coding region and splice sites of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. The spectrum of sequence changes comprises 54 different mutations, including 17 missense mutations, 14 nonsense mutations, 11 frameshift mutations, 10 splice site variants and two amino acid deletions. Eleven of these mutations have not previously been described. Our results reflect the marked mutational heterogeneity of CF in a large sample of patients from a non-isolated population.

Multicenter, Open-Label Study of Recombinant Human DNase in Cystic Fibrosis Patients With Moderate Lung Disease

Cystic fibrosis is characterized by the accumulation of thick viscous purulent secretions. Recombinant human deoxyribonuclease I (rhDNase) breaks down extracellular DNA, which contributes to the increased viscosity of sputum. A multinational, open‐label study was conducted in 974 cystic fibrosis patients with moderate lung disease [forced vital capacity (FVC) 40–70% of predicted values] to examine the safety and efficacy of aerosolized rhDNase, 2.5 mg, once daily over a period of at least 12 weeks. Patients were assessed under conditions reflecting routine clinical practice.

Idiopathic and Symptomatic Plastic Bronchitis in Childhood

During a one-year period we could observe 3 children with the rare disease of plastic bronchitis. Two of them showed a symptomatic form, one with constrictive pericarditis, the other with bronchial as

Increased Concentrations of Milk Antibodies in Recurrent Pulmonary Aspiration in Infants and Young Children

ABSTRACT. Concentrations of circulating antibodies against bovine serum albumin were significantly increased in six children with recurrent pulmonary aspiration (mean: 5.54 μg BSA‐N/ml, range: 2.05‐12.87 μg BSA‐N/ml; mean value of 76 control infants: 0.38 μg BSA‐N/ml, 95 % confidence interval: 0‐0.98 fig BSA‐N/ml, p<0.001) as determined by radioimmuno‐assay. IgG‐ and IgA‐isotypes against bovine serum albumin, lactalbumin, lactoglobulin, casein and gammaglobulin were determined in four patients by enzyme‐linked‐immuno‐sorbent‐assay. Significant differences between patients and controls were found for IgG‐antibodies against casein and bovine serum albumin and IgA‐antibodies against alpha‐lactalbumin and bovine serum albumin. Under certain conditions, stimulation of bronchus‐associated lymphoid tissue may lead to a higher immune response than oral immunization. Determination of milk antibodies may be helpful in the diagnosis of recurrent pulmonary aspiration.

Cystic fibrosis: the impact of analytical technology for genotype-phenotype studies

The generalized exocrinopathy cystic fibrosis (CF) is the most common severe genetic disease in Caucasian populations. A panel of more than 700 chromosomes from German and Turkish CF patients was screened for disease-causing mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene by chemical cleavage of mismatch, single strand conformation polymorphism, restriction analysis and direct sequencing of genomic DNA amplified by polymerase chain reaction. Besides the major 3-bp deletion, delta F508 that was found on 73% of German CF chromosomes, more than 50 other missense, nonsense, frame-shift, and splice-site mutations have already been identified. In general, a CFTR mutation is linked with a single 10-marker haplotype which indicates that in most cases a particular mutation spread from a common ancestor. The comparison of mutation genotypes with the disease phenotype emphasized the causative role of the type and localization of the CFTR mutation for clinical course and prognosis. Pancreatic status and the risk of colonization of airways with opportunistic pathogens are genetically determined. Most patients who are harbouring mutations in the nucleotide binding folds were suffering from severe CF disease. Mild or even aberrant forms of CF were observed for many missense mutations located in the putative transmembrane domains or for mutations that are expected to result in a truncated protein of half of wild-type CFTR.

Diagnostische Falle exogen allergische Alveolitis Typisch bei Aspergillusinfektion und Septischer Granulomatose

ZusammenfassungDie Septische Granulomatose wird durch die Unfähigkeit von Phagozyten hervorgerufen, aufgenommene Erreger mit Hilfe von mikrobizidem reaktivem Sauerstoff abzutöten. Besonders Formen der Septischen Granulomatose mit Restaktivität neigen dazu, andere Krankheitsbilder manchmal täuschend ähnlich nachzuahmen und den Behandler in eine diagnostische Falle zu locken. Eine klinisch bisher unauffällige 8jährige Patientin zeigte viele Symptome, die sehr gut mit einer exogen allergischen Alveolitis vereinbar waren, wie u.a. eine ausgeprägte restriktive Ventilationsstörung, ein suggestives Röntgenbild des Thorax, in der Mehrzahl CD8-positive Lymphozyten in der bronchoalveolären Lavageflüssigkeit sowie eine suggestive histologische Befundung. Hinweise auf die wahre Grunderkrankung, wie Neutrophilie und hoher Anti-Aspergillustiter konnten leicht übersehen werden. Da auch eine infektiöse Genese nicht auszuschließen war, wurde die Patientin in Unkenntnis der Grunderkrankung mit einer Kombination aus Antibiotika und Prednisolon behandelt. Nach kurzzeitiger deutlicher Besserung kam es zu einer dramatischen respiratorischen Verschlechterung mit massivem nun im Tracheobronchialsekret nachweisbaren Aspergillusbefall. Die Patientin verstarb unter dem Bild eines ARDS in der respiratorischen Insuffizienz trotz erfolgreich zurückgedrängter Aspergillusinfektion. Diskussion: In allen Fällen, bei denen die Septische Granulomatose zur Differentialdiagnose gehört, muß– insbesondere vor einer Steroidtherapie – eine adäquate Diagnostik erfolgen.SummaryChronic granulomatous disease (CGD) is caused by the inability of phagocytes to kill ingested germs by microbicidal reactive oxygen. Especially forms of CGD with retained ability to produce some reactive oxygen sometimes tend to imitate other diseases. An 8-year-old girl with a normal history presented with many symptoms matching those of hypersensitivity pneumonitis like restrictive ventilation disorder, suggestive chest x-ray, a majority of CD8 positive lymphocytes in the broncho-alveolar-lavage fluid (BAL), suggestive histological valuation. Hints for the true underlying disease like neutrophilia and a high anti-Aspergillus-titer could be overlooked easily. The patient was treated with steroids and antibiotics because an infection could not be excluded. The CGD had not been recognised at this time, however. After a significant improvement for a short time the patient experienced a dramatic respiratory deterioration. A lot of Aspergillus could now be found in the BAL. Finally the patient died because of an ARDS and respiratory insufficiency even though signs of the Aspergillus infection improved significantly. Discussion: Whenever CGD must be considered appropriate diagnostics have to be performed– especially before treatment with steroids.

DNA Typing of a Cystic Fibrosis Family with Borderline Sweat Tests

The quantitative pilocarpine iontophoresis sweat test (1) represents the most accurate physiological assay to diagnose cystic fibrosis (CF). However, about 2% of tested individuals consistently display sweat chloride concentrations in the borderline range of 50 to 70 mmol/l (2). In this case the uncertainty of the diagnosis of CF can be overcome by DNA typing. We report on a family with borderline sweat tests in which the status of the siblings was determined by the inheritance pattern of restriction fragment length polymorphisms (RFLPs) which are closely linked to the cystic fibrosis locus (3, 4).