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Twenty one children with cystic fibrosis were advised to decrease their pancreatic enzyme supplement (PES) dose to less than 10,000 units lipase/kg/day. Mean PES dosage was significantly decreased in 15 patients from 18,380 to 8647 units lipase/kg/day. There were no significant changes in energy or fat intake, but there were significant increases in weight SD score, height SD score, and weight/height ratio. [ABSTRACT FROM AUTHOR]

Although newborn screening for cystic fibrosis (CF) is widely advocated, hard evidence in its favor is difficult to obtain, partly because of a dramatically improved life expectancy. Between 1985--1989 infants, born in Wales and the West Midlands were randomized to newborn CF screening by heel-prick immunoreactive trypsin (IRT) measurement or diagnosis by clinical presentation. Eligible children with CF who died in the first 5 years of life were identified from the local pediatricians and from the National UK CF Survey. In all, 230,076 infants were randomized to be screened, while 234,510 were unscreened. One hundred seventy-six CF children were identified, of whom 7 died in the first 5 years of life, 3 having presented with meconium ileus. Median age of diagnosis in the screened group was 8 weeks. On an intention to treat analysis, all 4 nonmeconium ileus-related deaths occurred in the unscreened group (Fisher's exact test, P < 0.05). However, the clinical presentation of 2 of these infants led to them being diagnosed prior to 8 weeks, i.e., earlier than would have been likely by screening. In conclusion, newborn screening has the potential to decrease infant CF deaths, but if it is to be successful, identification and treatment must occur as soon as possible after birth., (Copyright 2001 Wiley-Liss, Inc.)

Background: A previous retrospective study suggested that a policy of regular anti-pseudomonal antibiotic treatment improved pulmonary function and increased survival in patients with cystic fibrosis chronically infected with Pseudomonas species. The results of a prospective multicentre study to compare the effects on pulmonary function and mortality of three monthly elective anti-pseudomonal antibiotic treatment with conventional symptomatic treatment are reported., Methods: Sixty patients with cystic fibrosis, chronically infected with P aeruginosa, were randomised to the two treatment arms (elective or symptomatic) and followed clinically at yearly reviews. The major end points were changes in forced expiratory volume in one second (FEV(1)) and forced vital capacity (FVC). Survival was a secondary end point., Results: Patients in the symptomatic group received a mean of three antibiotic treatments each year and those in the elective group received four antibiotic treatments during each year of the study. No significant differences in FEV(1) and FVC were found between the two groups after three years. There was a statistically non-significant higher rate of deaths in the elective group (n = 4), three of which were associated with B cepacia infection, compared with the symptomatic group (n = 0)., Conclusions: This study did not demonstrate an advantage of a policy of elective antibiotic treatment over symptomatic treatment in patients with cystic fibrosis chronically infected with Pseudomonas species.

From 1987 to 1994, 16 of 162 cystic fibrosis (CF) patients attending CF clinics at three different hospitals in South Wales, U.K. were found to have respiratory secretions colonized with Burkholderia cepacia (B. cepacia). Bacteriological typing by polymerase chain reaction (PCR) ribotyping demonstrated seven strains of B. cepacia among these 16 CF patients. This typing confirmed that cross-infection was the mechanism of colonization in six of the nine patients who were colonized at the paediatric CF clinic at the University Hospital of Wales in Cardiff, and in three of the six patients who were colonized at the adult CF clinic at Llandough Hospital in Cardiff (cross-infection rate nine of 16 patients or 56%). A search was made for a nosocomial source, with screening of wards and clinics. Swabs from fomites produced four positive cultures for B. cepacia. Two isolates had the same PCR ribotype as that of the previous CF room occupant. To establish prevalence of B. cepacia among CF children living throughout Wales, respiratory secretions were cultured from 151 of 186 CF children (age < 16 years). This failed to demonstrate B. cepacia colonization other than in the CF patients already identified.

We have performed an extensive mutation analysis on 184 CF families in Wales. In our previous study, mutations on 329/369 CF chromosomes were identified after screening for delta F508 and sixteen other mutations. To identify the mutations on the remaining 40 uncharacterized CF chromosomes, we have carried out direct DNA sequencing over the complete coding region, intron splice sites, and part of the promoter region of the CFTR gene. During this study we have designed a set of internal sequencing primers which allow clear sequencing through the aforementioned regions. Sequence analysis revealed 15 further mutations (4 of which are novel), and 10 previously described polymorphisms. In total, we have identified 29 mutations, the distribution of which provides further insight into the functional domains of the CFTR protein. We have characterised 99.5% of the CF chromosomes (365/367, one sample degraded). In order to ascertain accurate frequency data for the Welsh population, CF families with at least 3 'Welsh' grandparents were strictly regarded as 'Welsh'. Of these 91 families, delta F508 accounts for 71.6%, 621 + 1G-->T 6.6% and 1898 + 1G-->A 5.5%. The implications for CF population screening in Wales are discussed.

A detailed comparison of the severity of chest disease with mutational status was carried out by cross sectional study of 127 cystic fibrosis patients, aged 1 to 31 years, living in Wales. Lung disease was classified according to severity, depending on pulmonary function tests (carried out on 76 patients) and chest radiograph status; information was obtained also on age at diagnosis in relation to severity of chest disease and colonisation with Pseudomonas species. Genotypes were determined by analysis for the mutations delta F508, delta I507, G551D, R553X, G542X, R117H, R560T, 1717--IG > A, and 621 + 1G > T. CF patients homozygous positive and heterozygous for the delta F508 deletion showed a significant decline of lung function with age. Unlike other studies, we did not find patients homozygous positive for the delta F508 deletion to have poorer lung function compared with heterozygous patients. Patients with the genotype 621 + IG > T/delta F508 tended to have more severe chest disease than the delta F508 homozygous patients in the same age group. There was some evidence that four patients heterozygous for R117H have mild chest disease.

A father and son with profound reduction of exocrine pancreatic activity and little visible pancreatic tissue on ultrasound or computed tomography are described. Both have some degree of liver disease, which is more marked in the son. The disorder, apparently familial, does not correspond to any reported previously.

Neonatal screening for cystic fibrosis (CF) reduces short-term morbidity but its long term effects remain to be demonstrated. The best available method is the assay of immunoreactive trypsin in dried blood spots, and specificity can be improved by adding direct or indirect genetic analysis. Pregnancies known to be at risk of CF can also be screened by molecular methods, and affected pregnancies terminated. The application of genetic testing to whole communities, to detect unknown heterozygotes, raises many questions which require consideration by society and the health professions. The development of effective treatment of the basic abnormality of cell function in CF would enhance the need for neonatal screening, and possibly reduce the requirement for abortion.

Vitamin A status was examined in nine adult cystic fibrosis patients and six adult control subjects, together with an assessment of their ability to absorb 10,000 IU of retinyl palmitate from a test meal, taken with appropriate pancreatic enzyme supplements. Median baseline values for plasma retinol and carotene, as well as median serum retinol binding protein concentrations, were significantly lower in cystic fibrosis patients than in control subjects. One cystic fibrosis patient had a raised fasting plasma retinyl ester concentration suggestive of chronic hypervitaminosis A, but no symptoms of toxicity. Measures of vitamin A absorption were also significantly lower in cystic fibrosis patients, although there was considerable overlap with control values. No correlation was observed between measures of baseline status and vitamin A absorption. Measurement of plasma retinyl esters may be an appropriate investigation in those patients considered to be at risk of chronic hypervitaminosis A.

Vitamin E status was assessed in 22 patients with cystic fibrosis and 9 controls by measuring concentrations of the vitamin, vitamin E:lipid ratios and peroxide-induced haemolysis in plasma and erythrocytes. For a given concentration of plasma or erythrocyte alpha-tocopherol, erythrocytes of patients with cystic fibrosis were more susceptible to peroxide-induced haemolysis than controls. This susceptibility should be countered by supplementation with vitamin E to maintain higher than normal concentrations of circulating alpha-tocopherol-greater than 4.8 mmol alpha-tocopherol/mol cholesterol.

A total of 219 families of patients with cystic fibrosis living in Wales were studied for the occurrence of other diseases and for cause of death, and the findings in relation to leukaemia are reported. There were eight deaths due to leukaemia, five of the myeloid type, in first and second degree relatives; this is significantly more than the expected on the basis of national age specific mortality rates. In comparison, mortality among siblings, parents, aunts and uncles, and grandparents from all causes was within the expected. Screening the five patients with myeloid leukaemia for the delta F508 mutation showed that four were carriers of this mutation. It is concluded that carriers of the delta F508 mutation may have an increased risk of developing acute myeloid leukaemia. This could happen through the direct effect of the cystic fibrosis gene itself, or through its influence on another gene, such as the met oncogene, or gene(s) involved in granulocyte function on the long arm of chromosome 7.

Screening of the newborn for cystic fibrosis by measurement of immunoreactive trypsin has been undertaken on alternate weeks in Wales and the West Midlands for five years since 1985 to evaluate the possible clinical benefits of early diagnosis. Patients detected by screening and those diagnosed by clinical symptoms alone were assessed annually for differences in clinical, anthropometric, and biochemical variables. Fifty eight infants not considered to be at risk of cystic fibrosis (they did not present with meconium ileus and do not have a sibling with cystic fibrosis) have been detected by screening and they have been compared with 44 children who were diagnosed clinically. This latter group includes nine children whose screening was negative but who were recognised subsequently to have cystic fibrosis. The mean age at diagnosis of the screened group was significantly lower than that of the group diagnosed clinically. Excluding admissions for diagnostic tests for cystic fibrosis, the screened group spent a significantly shorter time in hospital during the first year of life. The results of all other comparisons made between the screened group and those diagnosed clinically were similar up to the age of 4 years.

Information on parents' attitudes towards neonatal screening for cystic fibrosis (CF) and antenatal diagnosis by chorion villus biopsy (CVS) has been derived from a detailed questionnaire administered to parents of CF babies diagnosed early following newborn screening (18 babies), and later on account of clinical criteria (11 babies). Screening was by measurement of immunoreactive trypsin (IRT) on Guthrie card blood spots, which was the basis of the Wales/West Midlands IRT Screening Survey, 1985-1989. Families questioned were from Wales. Most parents supported screening: parents of 15/18 (83%) screened babies and 10/11 (91%) unscreened babies. Following antenatal diagnosis, 15/29 (52%) of families would abort a CF foetus. Neither standard of education nor social class correlated with attitudes to screening or antenatal diagnosis, although these factors were related to the parents' knowledge of CF in general. Several families emphasised the importance of minimal delay between the initial mention of the possibility of CF on IRT testing and confirmation (or otherwise) of the diagnosis. Four mothers acknowledge temporary rejection of their babies during the period of uncertainty or following the procedures of diagnosis, emphasising that neonatal screening for CF can have a psychological impact on the parent-child bonding. Although most families supported neonatal screening for CF, this study underlines some of the difficulties which may be encountered during the procedure of screening for CF by IRT.

Immunogens from Aspergillus fumigatus were fractionated on the basis of molecular weight. Nine fractions ranging from 900 to 10 kDa were used in ELISA and in a radioallergosorbent test (RAST) with sera from cases of allergic bronchopulmonary aspergillosis (ABPA) and from cystic fibrosis (CF) patients with ABPA or other Aspergillus involvement and compared with control subjects. The profile of IgG reactivity to the nine fractions did not vary substantially for all Aspergillus-involved groups producing peaks at greater than 900 kD and 170 kD whereas the profile for control subjects had a peak at greater than 900 kD only. The IgE profile for CF patients with ABPA did not differ from the profile of the RAST-positive CF patients without ABPA and provided only one peak of activity at 24 kD. Recovery from an episode of ABPA in CF patients was accompanied by a fall in both IgG and IgE antibody levels to all nine fractions, whereas increases in IgG and IgE to all fractions were seen during an episode of ABPA. Although there was an exaggerated IgG increase to antigens in the 43-170 kD range during ABPA, a meaningful increase was also observed to unfractionated A. fumigatus antigen preparations. With IgE in one detailed study the 24-kD fraction provided a better indication of Aspergillus involvement than the unfractionated A. fumigatus antigens. Sequential studies of IgG and IgE levels were not able to predict an episode of ABPA but were useful in conjunction with clinical assessment in following the course of the illness.

Supplements of evening primrose oil (Oenothera biennis), which contains at least 72% linoleic (18:2n-6) and 7% gamma-linolenic (18:3 n-6) acids (expressed as % fatty acid methyl esters) were given to sixteen cystic fibrosis patients for a period of 12 months. Clinical observations showed no significant changes in patients' weights or respiratory function throughout. Linoleic acid levels in plasma and erythrocyte membranes increased significantly during the first 6 months but this increase was not sustained at its initial level. After supplementation was discontinued reversion to baseline (low) levels occurred within 4 months. Levels of plasma prostaglandins (PG) and urinary PG metabolites varied among individuals over a wide range, and urinary PGF2 alpha metabolites fell during the supplementation. There was a significant fall in sweat sodium concentrations after 6 weeks of supplementation, but sweat chloride was unchanged. It is not known whether the effect of essential fatty acids on sweat Na+ reflects changes in cell membrane conformation or if there is a direct effect on Na+ pump activity.

Phosphorylation of calmodulin-dependent regulator proteins has been studied in control and CF submandibular glands. Results showed that a 61,000 molecular weight calmodulin-binding protein was less phosphorylated in CF glands than control (p less than 0.001 for difference). The altered calmodulin-binding protein cross-reacted with an antiserum against a known calmodulin-dependent protein phosphatase, calcineurin. An alteration in a protein with calcineurin-like activity in CF epithelial cells would provide a link between defective beta-adrenergic responses and altered Ca2(+)-mediated events in CF and thus might be directly related to the genetic defect.

A novel collecting device was used to obtain pure submandibular saliva from control and Cystic Fibrosis (CF) individuals. Vitamin C stimulation induced a 2-fold increase in flow rate relative to resting; CF rates were lower under both conditions. Control and CF saliva differed in that stimulation did not result in increased Na+ and Cl- levels in CF saliva and that elevated levels of Ca2+ and PO4(2-) were observed in CF. The results imply altered electrolyte secretion in CF in response to a stimulus in vivo.

Adrenergic secretory responses of submandibular glands from control subjects and cystic fibrosis patients have been studied in vitro. In control tissues, isoproterenol (10 mumol/l) and noradrenaline (10 mumol/l) increased release of mucins and amylase to a similar extent (approximately 3-fold) and their actions were mediated by stimulation of beta-adrenergic receptors. In cystic fibrosis tissues, isoproterenol did not significantly increase release of mucins or amylase above the basal rate during 40 min incubation, whereas secretion in response to noradrenaline was not significantly different from that in control tissues. In the presence of a phosphodiesterase inhibitor, secretion of mucins and amylase in response to isoproterenol (10 mumol/l) in cystic fibrosis tissues was increased to the same level as that of noradrenaline (10 mumol/l); giving the same pattern of adrenergic responses in cystic fibrosis tissues as in control. The results suggest that overactivity of phosphodiesterase in cystic fibrosis cells might be the cause of the observed decreased secretion in response to a beta-adrenergic agonist.

Linkage between the locus for cystic fibrosis and other genetic markers was explored in 40 families from Birmingham and 20 from Manchester. No strong evidence was found for linkage with any of the markers examined. There was evidence against close linkage with ABO, HLA, and Rh.

A study programme was set up in Wales and the West Midlands to evaluate serum immunoreactive trypsin screening for cystic fibrosis in neonates using blood spots collected for metabolic screening. By screening half the blood spots from each area, it was hoped to generate two comparable groups of fibrocystic children; those detected by screening and those not screened who would be diagnosed clinically. Over almost three years, more than 120,000 specimens were screened and 37 infants detected with cystic fibrosis. Four additional fibrocystic patients were missed on screening: two had negative immunoreactive trypsin values, of which one had meconium ileus, and two, although giving initial positive tests, were negative on follow up. Excluding infants known to be at risk, comparison of the numbers of children detected in the screened and unscreened groups showed more than a two-fold difference in favour of the screened group. There may be a large number of undiagnosed fibrocystic patients in the general population.

Phosphoinositide phospholipase C activity has been measured in erythrocyte membranes from age-matched control and CF subjects. Inositol phospholipids were labelled with [3H]myo-inositol and control experiments demonstrated that the [3H]-labelled products released by incubation of membranes with Ca2+ were derived specifically from erythrocytes (a) by purification of erythrocytes on cellulose columns, (b) by demonstration that the phospholipase C activity was inhibited by 10 mmol/l neomycin but not by 1 mmol/l p-methylsulphonylfluoride. The [3H]-labelled products were shown to be inositol phosphates by their elution from anion-exchange columns. Membranes from CF patients showed increased phospholipase C activity compared to controls which did not correlate with the degree of [3H]inositol labelling of the membranes, with pancreatic function as assessed by serum immunoreactive trypsin or with medications taken by the patients.

Calmodulin-binding proteins in fractions purified from human submandibular glands by calmodulin-Sepharose were phosphorylated with [gamma-32P]ATP, in the absence of exogenous protein kinase. The major proteins phosphorylated had molecular masses of 45, 51 and 61 kDa. Phosphorylation was increased by activators of protein kinase C and inhibited by H-7. Phosphorylation of the 61 kDa band was markedly decreased in cystic-fibrosis submandibular glands.

Boiled extracts of buccal epithelial cells from control subjects and cystic fibrosis patients were shown to possess calmodulin like activity, as assessed by their ability to activate calmodulin-deficient cyclic AMP phosphodiesterase. Estimation of calmodulin content, using pure calmodulin as standard revealed that control extracts contained 3.08 +/- 0.71 SEM (n = 7) micrograms calmodulin/mg protein and cystic fibrosis extracts 0.88 +/- 0.30 SEM (n = 12) micrograms calmodulin/mg protein (p less than 0.02 for difference from control). The results indicate that the biological activity of calmodulin is altered in buccal epithelial cells from cystic fibrosis individuals.

Liver scans were performed on 16 cystic fibrosis patients. Most scans were considered abnormal. In most patients, the results of serological liver function tests were normal. Liver scanning in cystic fibrosis is unlikely to make a significant contribution to an assessment of prognosis.

The in-vitro investigation of secretory responses of submandibular tissues from three cystic fibrosis (CF) patients and four control subjects showed that responses to a beta-adrenergic stimulus (isoproterenol) were much poorer in CF cells than in control cells. The beta-adrenergic secretory responses of the CF cells (as measured by amylase and mucin secretion) were increased in the presence of 3-isobutyl-l-methyl xanthine, a cyclic nucleotide phosphodiesterase inhibitor. Perhaps an alteration in a regulator of cyclic adenosine monophosphate and Ca2+ metabolism in CF cells is responsible for the decrease in beta-adrenergic function. This proposal would account for the defective regulation of protein secretion, Cl- transport, and Ca2+ homoeostasis in CF exocrine cells and thus might be directly related to the genetic defect.