Diversity of the basic defect of homozygous CFTR mutation genotypes in humans.

BACKGROUND: Knowledge of how CFTR mutations other than F508del translate into the basic defect in cystic fibrosis (CF) is scarce due to the low incidence of homozygous index cases. METHODS: 17 individuals who are homozygous for deletions, missense, stop or splice site mutations in the CFTR gene were investigated for clinical symptoms of CF and assessed in CFTR function by sweat test, nasal potential difference and intestinal current measurement. RESULTS: CFTR activity in sweat gland, upper airways and distal intestine was normal for homozygous carriers of G314E or L997F and in the range of F508del homozygotes for homozygous carriers of E92K, W1098L, R553X, R1162X, CFTRdele2(ins186) or CFTRdele2,3(21 kb). Homozygotes for M1101K, 1898+3 A-G or 3849+10 kb C-T were not consistent CF or non-CF in the three bioassays. 14 individuals exhibited some chloride conductance in the airways and/or in the intestine which was identified by the differential response to cAMP and DIDS as being caused by CFTR or at least two other chloride conductances. DISCUSSION: CFTR mutations may lead to unusual electrophysiological or clinical manifestations. In vivo and ex vivo functional assessment of CFTR function and in-depth clinical examination of the index cases are indicated to classify yet uncharacterised CFTR mutations as either disease-causing lesions, risk factors, modifiers or neutral variants.

Carbohydrate-deficient glycoprotein syndrome type Ib. Phosphomannose isomerase deficiency and mannose therapy.

Phosphomannose isomerase (PMI) deficiency is the cause of a new type of carbohydrate-deficient glycoprotein syndrome (CDGS). The disorder is caused by mutations in the PMI1 gene. The clinical phenotype is characterized by protein-losing enteropathy, while neurological manifestations prevailing in other types of CDGS are absent. Using standard diagnostic procedures, the disorder is indistinguishable from CDGS type Ia (phosphomannomutase deficiency). Daily oral mannose administration is a successful therapy for this new type of CDG syndrome classified as CDGS type Ib.

Dornase alfa in the treatment of cystic fibrosis in Europe: a report from the Epidemiologic Registry of Cystic Fibrosis.

Dornase alfa (Pulmozyme) treatment for patients with cystic fibrosis (CF) has been shown to improve pulmonary function and reduce exacerbations of infection in a number of placebo-controlled double-blind studies. Data in the Epidemiologic Registry of Cystic Fibrosis (ERCF) in November 1998 were used to assess the long-term effectiveness in routine clinical practice of dornase alfa in terms of pulmonary function and frequency of acute pulmonary exacerbations in CF. At that time, the ERCF contained data on 13,684 CF patients, with a mean observation period of 2.3 years. To be included in the analysis, patients had to have 2 years of data in the Registry in appropriate detail. Overall, untreated patients showed a decline in forced expiratory volume in 1 sec over a 2-year period of -2.3% predicted, but treated patients were stable, showing a change of 0.3% predicted, i.e., a treatment benefit of 2.5%. Compared to untreated patients, there were 25 fewer exacerbations per 100 treated patients per year. The analysis suggested that younger patients were likely to benefit more from treatment. The findings of randomized clinical trials were supported by the data collected in routine clinical practice.

Correlation of IgE antibody titer to Aspergillus fumigatus with decreased lung function in cystic fibrosis.

Obstructive pulmonary disease is a typical feature of cystic fibrosis (CF) and is often associated with bronchial hyperreactivity. Positive skin-test reactions to Aspergillus fumigatus antigens are frequently seen even in nonatopic patients with CF. Full-fledged allergic bronchopulmonary aspergillosis (ABPA) has been estimated to occur in 10% of patients with CF. The relationship between lung function and presence of IgE antibodies to Aspergillus antigens in patients without ABPA is not clear. In 148 outpatients with CF (aged 6-34 years) specific immunoglobulin E (IgE) to Aspergillus fumigatus antigens, basic lung-function parameters, and bronchial response to salbutamol were measured. Multiple regression was performed for age, weight as percentile for actual height (indicating general condition), and Aspergillus RAST. Aspergillus IgE was present in 46% of patients; 19% had RAST class 3 or 4. Independent negative correlations of Aspergillus RAST with FEV1, FEF50%, FEF25%, RV, Chrispin Norman score, and sRaw (P less than 0.05) were found. Bronchodilator sensitivity did not correlate significantly with age and weight percentile. However, Aspergillus RAST did correlate significantly with bronchodilator response measured by sRaw (P less than 0.05). High titers of Aspergillus RAST might serve as a selective criterion for patients to be included in future studies evaluating broncholytic or antiphlogistic therapies.

International practice patterns by age and severity of lung disease in cystic fibrosis: data from the Epidemiologic Registry of Cystic Fibrosis (ERCF).

The Epidemiologic Registry of Cystic Fibrosis provides clinical profiles for more than 6,800 patients and descriptions of practice patterns across eight European countries. Preliminary cross-sectional analysis has been performed by age and pulmonary function as an assessment of disease severity. In general, pulmonary treatments including inhaled bronchodilators and rhDNase increased as lung disease became more severe. Use of a number of treatments, including mucolytic agents and inhaled corticosteroids, varied markedly from country to country. Several widely used therapies are not yet supported by controlled clinical trials, particularly in patients under 6 years of age. Nutritional intervention was more common in patients with advanced lung disease regardless of age. Patients with nasal polyps had less severe lung disease at each age than patients without polyps. It is clear that studies of early interventions are needed to determine the optimal types of treatments and the ages at which to begin treatment.

Presence of cystic fibrosis-related diabetes mellitus is tightly linked to poor lung function in patients with cystic fibrosis: data from the European Epidemiologic Registry of Cystic Fibrosis.

Data derived from a cross-sectional analysis of 7,566 patients stratified into six age groups were used to compare lung function, body mass index (BMI), and weight for age in patients with and without cystic fibrosis-related diabetes mellitus (CFDM). The presence of CFDM was tightly linked to poor lung function, regardless of age. The mean value of FEV(1) % predicted in the age groups < 10, 10-< 15, 15-< 20, 20-< 25, 25-< 30, and 30 years or older were 87%, 77%, 69%, 58%, 55%, and 53% in the nondiabetic cystic fibrosis (CF) patients as compared to 79%, 66%, 55%, 49%, 46%, and 44% in the diabetic CF patients. BMI and weight for age were also lower in diabetic than nondiabetic CF patients in all age groups, except for BMI in the youngest patients. The difference in lung function and in nutritional parameters between diabetic and nondiabetic CF patients was not linked to presence or absence of any specific pathogen in the lower respiratory tract. These results confirm and extend those of earlier studies in smaller numbers of patients, and they clearly identify CFDM as a powerful determinant of severe lung disease and reduced survival in patients with CF and diabetes mellitus.

Multicenter, open-label study of recombinant human DNase in cystic fibrosis patients with moderate lung disease. DNase International Study Group.

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. During rhDNase therapy, at least one respiratory tract infection (RTI) requiring intravenous antibiotics was experienced by 29.5% of patients. Forced expiratory volume in 1 second (FEV1) and FVC were significantly improved from baseline by a mean of 10.5% and 7.2%, respectively. Voice alteration and pharyngitis were the most frequent rhDNase-related adverse events, but only 2% of all patients discontinued treatment due to adverse events. The results obtained were similar to a subanalysis of data from the first 3 months of a placebo-controlled U.S. study. The patients in the present study had a similar frequency of RTIs and improvement in pulmonary function, and reported fewer rhDNase-related and cystic fibrosis-related adverse events than patients in the U.S. study. We conclude that administration of rhDNase is safe, well tolerated, and effective under conditions reflecting routine clinical practice in patients with cystic fibrosis and moderate lung disease.

Biliary atresia: which factors predict the success of a Kasai operation? An analysis of 36 patients.

UNLABELLED: Biliary atresia (BA) is one of the most frequent causes of neonatal cholestasis. Portoenterostomy is one therapeutic option in these patients with a success rate of 30-40%. To answer the question of therapy liver transplantation or Kasai operation - we analyzed 36 consecutive patients being followed in our center during the past 7 years. Two groups were formed: group I : patients developing cirrhosis within the first 2 years of life with the need for liver transplantation (n = 21). Group II: patients without need for transplantation within the first 2 years of life (n = 15). The two groups were compared regarding birth weight, age at diagnosis, age at Kasai-procedure, liver histology. The following biochemical parameters were analyzed at the time of diagnosis, 1 week and 5 weeks after Kasai: AST, ALT, gammaGT, and bilirubin. - RESULTS: Clinical characteristics were similar in both groups. However BA was diagnosed in group I 8.2 weeks after birth compared to 5.6 wk in group II. gammaGT, ALT, AST, and bilirubin were similar in both groups at the time of diagnosis and 1 wk after Kasai. However 5 wk after Kasai gammaGT was 276 U/l in group I compared to 72 U/l in group II (p <0.001), bilirubin was 6.3mg/dl in group I compared to 2. 3mg/dl in group II (p <0.001). - CONCLUSION: Kasai operation before the 7th wk of life increases the success rate of this technique significantly. Children with cirrhosis at the time of diagnosis should be evaluated for primary liver transplantation. gammaGT and bilirubin 5 weeks after Kasai operation may be useful markers for the success of this procedure. Patients with a gammaGT > 100 U/l and a bilirubin level >5mg/dl should be followed closely and should be evaluated for liver transplantation early.

Renal function and renotropic effects of secretin in cystic fibrosis.

In ten cystic fibrosis patients and nine age-matched controls, renal function was determined before and after infusion of secretin. Under baseline conditions creatinine excretion and clearance were significantly elevated, exclusively due to those patients who were homozygous for the DF508 mutation (153 vs 132 ml/min*1.73m2), whereas the glomerular filtration rate, measured by inulin clearance showed no difference. Renal plasma flow and the fractional reabsorption rates of electrolytes were similar in patients and controls. During secretin infusion renal plasma flow increased and the fractional reabsorption rates of electrolytes decreased in both groups. The patients had a increased metabolic clearance (2900 vs 1660 ml/min*m2) and endogenous production rate (9,9 vs 2,5 pmol/min*m2) of of secretin. In conclusion global renal function and electrolyte handling, in particular chloride permeability, are unchanged in cystic fibrosis. Individuals expressing the DF508 genotype showed a selective elevation of creatinine excretion and clearance. The secretion and metabolic clearance of secretin are increased in cystic fibrosis.

[Ulcerative colitis in childhood and its differential diagnosis]. / Die Colitis ulcerosa im Kindesalter und ihre Differentialdiagnose.

Ulcerative colitis occurs before the age of 15 years in 20% and before 20 years in 40% of all patients involved. The frequency of this disease in patients at the University Children's Hospital of Munich has clearly risen over the past years. In many patients we found characteristic differences in history, clinical picture and laboratory results as compared with Crohn's disease. The most important diagnostic procedure is endoscopy of the entire colon. The histological examination of the biopsies taken during colonoscopy differentiated less clearly between these two entities than the macroscopic judgement by the endoscopist. The development of carcinoma must be considered even in children when the disease has lasted for seven years or longer. Ulcerative colitis must be differentiated from infectious diseases of the bowel by direct search for the relevant microorganisms and by serological testing.

[Significance of endoscopy in inflammatory bowel diseases in childhood]. / Die Bedeutung der Endoskopie bei entzündlichen Darmkrankheiten im Kindesalter.

Endoscopy makes an essential contribution as diagnostic tool in the clarification of unspecific inflammatory bowel disease in childhood. Important advantages of this method are detection of early lesions, classification of the type of inflammation, sight-guided biopsies and no exposure to X-rays. In 36 patients the diagnosis of Crohn's disease was proven by endoscopy alone in 66.6% of cases, by histology as sole criterion in 69.4%, and by X-ray examination alone in only 8.3% of cases. All 3 patients in whom the diagnosis of Crohn's disease was made exclusively by radiological means showed manifest involvement limited to the small bowel. However, even upper gastrointestinal endoscopy led to the detection of lesions characteristic of Crohn's disease in some cases. 36 colonoscopies were performed in 28 patients with ulcerative colitis. Typical lesions were detected endoscopically in 91.7%; corresponding histological changes were found in only 63.6%.

A paediatric Crohn's disease activity index (PCDAI). Is it useful? Study Group on Crohn's Disease in Children and Adolescents.

Since 1976, various activity indices for Crohn's disease have been developed but none has been suitable for use in the paediatric age group. Therefore, the German-Swiss Study Group on Crohn's Disease in Children and Adolescents decided to develop their own paediatric Crohn's disease activity index (PCDAI) by multiple regression analysis of prospectively collected data. The result was a simple index consisting of two clinical (appetite, number of stools/week) and four laboratory variables (erythrocyte sedimentation rate, serum iron and alpha 2-globulin concentrations and bands as percentage of white blood cells). Applying the index to patients who were followed-up, it could be demonstrated that the changes in PCDAI inversely reflected the changes in weight and that the surgical removal of the inflamed parts of the gut reduced the disease activity index to levels comparable to those obtained in patients after successful, exclusively conservative, treatment. Low disease activity was maintained for at least three years.

[Cow's milk protein sensitive enteropathy]. / Die kuhmilcheiweissabhängige Darmkrankheit des jungen Säuglings, eine Form der Kuhmilchproteinintoleranz.

Cow's milk protein sensitive enteropathy (CMPSE) is characterized by the following items: 1. The great majority of affected infants have not been breast fed or only for a few days. Additional risks are immaturity, preceding enteritis, trisomy 21, and abdominal operation in the newborn. 2. Half of the patients become ill during the first two weeks after starting cow's milk formula. The main symptoms are watery, mucus containing diarrhea, vomiting, abdominal distension, pallor and rapid weight loss. 3. In CMPSE the small intestinal mucosa shows varying degrees of inflammation and villous atrophy. Bloody stools refer to large bowel affection. 4. CMPSE is always transitory and usually persists for less than one year. Inadequate treatment leads to "severe protracted diarrhea" or "intractable diarrhea" syndrome. Soya-based formula should not be the diet of first choice, since secondary intolerance to soya proteins will frequently develop. Exclusive breast feeding during the first months of life is the best prophylaxis of CMPSE.

[Severe protracted diarrhea in infancy ("intractable diarrhea")]. / Die schwere protrahierte Säuglingsdiarrhoe ("intractable diarrhoea").

In most cases, protracted diarrhea in infants is due to lack of human breast milk, and iatrogenic malnutrition. Damage to the mucosa of the small intestine maintained by cow's milk proteins and malnutrition constitute main parts of a vicious circle interrupted by completely parenteral nutrition for some time, and slow reintroduction of human breast milk. This kind of therapy reduced mortality significantly. The best prophylaxis is the full support of breast feeding. As differential diagnosis the familial lethal diarrhea of the breast fed infant has to be considered. Furthermore, in case of diarrhea lasting for longer than two weeks, other less frequent causes have to be thought of, as pointed out briefly.

[Cystic fibrosis and celiac disease. Report of two cases]. / Zystische Fibrose und Zöliakie. Zwei Fallbeschreibungen.

Two patients with cystic fibrosis who subsequently developed celiac disease are described. Difficulties in the diagnosis of coexistence of both diseases are discussed.

Calcium metabolism and cystic fibrosis: mitochondrial abnormalities suggest a modification of the mitochondrial membrane.

A disorder of calcium (Ca2+) metabolism may be central to the pathogenesis of cystic fibrosis (CF). Average cellular Ca2+ levels in fibroblasts derived from patients with CF (ages, 14-25 yr; n = 25) were 36-77% higher than in matched controls depending on age of cell culture (9.0-10.6 versus 5.1-7.8 nmol/mg cellular protein). Cellular Ca2+ was significantly elevated in CF, but was not a reliable criterion for identifying CF cells because of the high variability of results. Studies of Ca2+ fluxes in cell organelles showed that mitochondria isolated from CF fibroblasts accumulate 2-3 times more Ca2+ than controls [79.5 +/- 8.2 versus 33.7 +/- 4.7 nmols X mg mitochondrial protein-1 X 10 min-1 (+/- SD)], Ca2+ accumulation in mitochondrial reliably distinguished between CF and control or heterozygote cells (P less than 0.0005, n = 11). In vitro experiments showed that Ca2+ influx and efflux are increased in isolated CF mitochondria, resulting in net Ca2+ accumulation. Ca2+ uptake in mitochondria is energy-dependent; some inhibitors of mitochondrial energy metabolism (atractyloside, oligomycin) influenced Ca2+ intake significantly more in CF than in control mitochondria. Furthermore, the average activities of NADH oxidase, NADH- and succinate-cytochrome c reductase were 77, 58, and 48% higher in CF mitochondria, respectively. This indicates that many functions associated with energy metabolism and the mitochondrial membrane (electron transport, ATP transport, and ATP hydrolysis) are not operating properly in CF, thus possibly causing the derangement of Ca2+ metabolism found in CF mitochondria and cells.

Genetic determination of diabetes mellitus in patients with cystic fibrosis. Multicenter Cystic Fibrosis Study Group.

Data from 1348 patients with cystic fibrosis in mid-Europe show that the prevalence of diabetes mellitus in these patients is 4.9%, that diabetes develops in more female than male patients with cystic fibrosis during childhood and adolescence and at a younger age, and that diabetes mellitus is more likely to affect delta F508 homozygous patients.

The fluorescent immunosorbent test for IgG gliadin antibodies and the leucocyte migration inhibition test in coeliac disease; comparison of diagnostic value.

The diagnostic value of the fluorescent immunosorbent test for IgG gliadin antibodies (FIST) has been investigated in comparison with the LIF test--the competence of the gluten subfractions B2 and B3 in releasing lymphokines from peripheral lymphocytes in vitro--in 96 patients with coeliac disease (CD) under various dietary conditions. In untreated children with CD during their first 2 years of life, the FIST showed 100% sensitivity with 95% specificity, whilst the LIF test showed only 70% sensitivity and 73% specificity. Therefore it can be concluded that the FIST as a screening test is superior to the LIF. In older children with a proved recurrence of the mucosal abnormality after reintroduction of a normal diet, only 44% showed increased IgG gliadin antibody titres whereas 70% proved to be positive in the LIF test. Under a controlled gluten challenge all six patients reacted with a distinct increase in gliadin antibody titres whereas the LIF test changed from positive to negative and vice versa without following any clear principle. These results emphasize the inadequacy of the LIF test as a diagnostic method, both in untreated CD and under controlled gluten challenge.

[The usefulness of the Chrispin-Norman score in the evaluation of pulmonary status in patients with cystic fibrosis]. / Die Wertigkeit des Chrispin-Norman-Score in der Beurteilung der pulmonalen Situation von Patienten mit Cystischer Fibrose.

Its objectivity and reproducibility having been checked by for independent researchers, the Chrispin-Norman score has proved to be a useful yardstick for evaluating pulmonary changes in cystic fibrosis. The correlation to arterial pO2 was r = 0.68, and to the Schwachman-Kulczycki score, r = 0.75. Scores still consistent with a good general clinical condition were 10.5 in patients under 8 years of age; 13.4 in patients aged between 8 and 13; and 15.5 in the 13-20 age group. An average increase of more than 2 points a year indicates a particularly high danger level.

Vitamin B12 absorption and exocrine pancreatic insufficiency in childhood.

The absorption of vitamin B12, labelled with radioactive 58Co, was measured in 19 patients with cystic fibrosis and one child with the Shwachman-Diamond syndrome using the whole body counting technique. We found vitamin B12 absorption reduced to 7.97 on average, compared to 59.2% for the control group. The low vitamin B12 absorption correlated well with the reduced fat retention coefficients. After adding 0.212 pancreatin to the radioactive vitamin B12 test dose, the absorption quotas improved in all cases, the average being 61%. A meal poor in vitamin B12 tended to increase the absorption of the radioactive test dose to 23% on average. As yet there is no satisfactory explanation for the effect of the diet on the absorption of vitamin B12 in exocrine pancreatic insufficiency. This could be the reason why the malabsorption of vitamin B12 in patients with EPI can go unnoticed for many years and could possibly explain why vitamin B12 malabsorption in exocrine pancreatic insufficiency does not cause symptoms and signs of vitamin B12 deficiency for many years.