Characterization of CFTR mutations in people with cystic fibrosis and severe liver disease who are not eligible for CFTR modulators.

Cystic-fibrosis-related liver disease (CFLD) is a variable phenotype of CF. The severe CFLD variant with cirrhosis or portal hypertension has a poor prognosis and life expectancy. CFTR modulator therapies are now available for people with CF and eligibility for such treatment is based on their CFTR genotype. We evaluated the genetic eligibility for elexacaftor, tezacaftor, ivacaftor (ETI), and ivacaftor (IVA) monotherapy in a previously reported CF cohort of 1591 people with CF of whom 171 with severe CFLD. Based on their CFTR mutations, 13% (N=184/1420) of subjects without CFLD and 11% (N=19/171) of those with severe CFLD are not eligible for either ETI or IVA therapy. The non-eligible patients without CFLD or with severe CFLD can currently not take advantage of the potential benefits of these new treatments. Although this study cannot provide any data regarding the effect of ETI or IVA on the progression of severe CFLD, the consequences for ineligibility of patients with extreme liver phenotype may be even more significant because of their poorer disease risk profile.

Effects of prolonged proton pump inhibitor treatment on nutritional status and respiratory infection risk in cystic fibrosis: A matched cohort study.

BACKGROUND: Evidence on the effectiveness of proton pump inhibitors (PPI) as adjuvant therapy to improve maldigestion in people with cystic fibrosis (pwCF) is limited and there is increasing concern on possible side effects. METHODS: We conducted a matched cohort study based on paediatric and adult pwCF who received PPI for ≥3 months. Treated patients were matched to a group of patients who never received PPI using a nearest neighbour propensity score matching based on sex, year of birth, CFTR genotype and pancreatic insufficiency. RESULTS: The study included 160 pwCF: 80 treated and 80 untreated patients. Over a median follow-up of 2 years, no significant differences in changes in BMI z-score were detected between groups (adjusted mean difference: 0.06, 95% CI: -0.17-0.30). At baseline 25% (n = 20) of the treated patients and 22.5% (n = 18) of the untreated patients had a positive culture for P. aeruginosa (Pa). At follow-up percentages of Pa positive cultures increased to 47.5% (n = 38) in the treated group and to 26.3% (n = 21) in the untreated group (adjusted mean difference: 23.1%, 95% CI: 10.8-35.3). CONCLUSIONS: Prolonged PPI therapy should be used cautiously in pwCF since it may increase the risk of respiratory infection by Pa. In addition, such treatment does not seem to improve nutritional status.

A successful treatment of a lobar atelectasis in a patient with cystic fibrosis.

Lobar atelectasis may be a complication of pulmonary exacerbations in cystic fibrosis (CF). There are no established guidelines on the management of this condition in patients with CF. Therapeutic bronchoscopy with recombinant human deoxyribonuclease (rhDNase) instillation has been described to be successful in patients not responding to conservative measures. We describe a case of a young man with CF, with previously mild impaired lung function, presenting with cough, desaturation, and worsening dyspnea, persisting for over 6 weeks, despite conservative therapy. Thoracic imaging showed right lower lobe atelectasis, which was successfully treated with bronchoscopy and instillation of rhDNase. Long-term resolution of the atelectasis was confirmed with chest magnetic resonance imaging follow-up.

Ursodeoxycholic acid and liver disease associated with cystic fibrosis: A multicenter cohort study.

BACKGROUND: The efficacy and safety of ursodeoxycholic acid (UDCA) for the treatment of liver disease associated with cystic fibrosis (CF) are under discussion, and clinical practice varies among centers. The study aimed at evaluating if the incidence of severe liver disease differs between CF centers routinely prescribing or not prescribing UDCA. METHODS: We carried out a retrospective multicenter cohort study including 1591 CF patients (1192 patients from UDCA-prescribing centers and 399 from non-prescribing centers) born between 1990 and 2007 and followed from birth up to 31 December 2016. We computed the crude cumulative incidence (CCI) of portal hypertension (PH) at the age of 20 years in the two groups and estimated the subdistribution hazard ratio (HR) through a Fine and Gray model. RESULTS: Over the observation period, 114 patients developed PH: 90 (7.6%) patients followed-up in UDCA prescribing centers and 24 (6.0%) in non-prescribing centers. The CCI of PH at 20 years was 10.1% (95% CI: 7.9-12.3) in UDCA-prescribing and 7.7% (95% CI: 4.6-10.7) in non-prescribing centers. The HR among patients followed in prescribing centers indicated no significant difference in the rate of PH either in the unadjusted model (HR: 1.21, 95% CI: 0.69-2.11) or in the model adjusted for pancreatic insufficiency (HR: 1.28, 95% CI: 0.77-2.12). CONCLUSIONS: CF patients followed-up in UDCA prescribing centers did not show a lower incidence of PH as compared to those followed in centers not prescribing UDCA. These results question the utility of UDCA in reducing the occurrence of severe liver disease in CF.

Molecular typing of Burkholderia cepacia complex isolated from patients attending an Italian Cystic Fibrosis Centre.

Bacteria from the Burkholderia cepacia complex (Bcc) are capable of causing severe infections in patients with cystic fibrosis (CF). Bcc infection is often extremely difficult to treat due to its intrinsic resistance to multiple antibiotics. In addition, it seems to speed up the decline of lung function and is considered a contraindication for lung transplantation in CF. This study investigates the species of the Bcc strains recovered from chronically infected CF subjects by means of: isolation, identification methods and complete recA nucleotide sequences of 151 samples. Molecular typing showed that B. cenocepacia III is the dominant strain found in the group of subjects being treated at the Milan CF Centre (Italy) and that the infection is chronically maintained by the same species. Defining species by means of molecular analysis yields important information for the clinician in order to establish the most appropriate therapy and implement correct measures for prevention of transmission among CF subjects.

Long-Term Ursodeoxycholic Acid Therapy Does Not Alter Lithocholic Acid Levels in Patients with Cystic Fibrosis with Associated Liver Disease.

OBJECTIVE: To evaluate the fasting and postprandial serum bile acid composition in patients with cystic fibrosis-associated liver disease (CFLD) after chronic administration of ursodeoxycholic acid (UDCA) (20 mg/kg/day). The aim was to specifically focus on the extent of biotransformation of UDCA to its hepatotoxic metabolite, lithocholic acid, because of recent concerns regarding the safety of long-term, high-dose UDCA treatment for CFLD. STUDY DESIGN: Twenty patients with CFLD (median age 16 years, range: 2.4-35.0) prescribed UDCA therapy for at least 2 years were studied. Total and individual serum bile acids were measured by stable-isotope dilution mass spectrometry, in fasting and 2-hour postprandial samples taken during chronic UDCA (20 mg/kg/day) administration. RESULTS: During chronic UDCA administration (median duration 8 years, IQR: 6-16), UDCA became the predominant serum bile acid in all patients (median, IQR: 3.17, 1.25-5.56 µmol/L) and chenodeoxycholic acid concentrations were greater than cholic acid (1.86, 1.00-4.70 µmol/L vs 0.40, 0.24-2.71 µmol/L). The secondary bile acids, deoxycholate and lithocholate, were present in very low concentrations in fasted serum (<0.05 µmol/L). After UDCA administration, 2-hour postprandial concentrations of both UDCA and chenodeoxycholic acid significantly increased (P < .01), but no significant changes in serum lithocholic acid concentrations were observed. CONCLUSION: These data do not support recent suggestions that enhanced biotransformation of UDCA to the hepatotoxic secondary bile acid lithocholic occurs when patients with CFLD are treated with relatively high doses of UDCA.

Bowel ultrasound imaging in patients with cystic fibrosis: Relationship with clinical symptoms and CFTR genotype.

BACKGROUND: Ultrasound imaging is used to assess bowel abnormalities in gastrointestinal diseases. We aimed to assess the rate of predefined bowel ultrasound signs and their relationship with gastrointestinal symptoms and the cystic fibrosis transmembrane conductance regulator (CFTR) genotype in cystic fibrosis patients in regular follow-up. METHODS: Prospective study of 70 consecutive patients with cystic fibrosis and 45 controls who underwent abdominal ultrasound; pertinent findings were related to gastrointestinal symptoms and, in cystic fibrosis patients, to pancreatic status, malabsorption degree, lipase intake, CFTR genotype (classified as severe or mild against functional class of CFTR mutations). RESULTS: 96% patients showed at least one abnormal bowel ultrasound sign. Most frequent signs were lymph node enlargement (64%), bowel loop dilatation (55%), thick corpuscular intraluminal content (49%), bowel wall hypervascularization (26%), thickened bowel wall (22%) and intussusception (17%). Patients with recurrent abdominal pain showed more bowel wall hypervascularization than patients without recurrent pain (47% vs. 19%, respectively; p = 0.02) and intussusception (58% vs. 17%, respectively; p < 0.01). Genotype was not associated to specific bowel ultrasound signs. Patients with bowel loop intussusception showed greater lipase intake than those without intussusception (8.118 ± 2.083 vs. 5.994 ± 4.187, respectively; p < 0.01). CONCLUSION: Cystic fibrosis patients present a higher rate of bowel ultrasound abnormalities than controls. Bowel ultrasound abnormalities are associated with abdominal symptoms.

Clinical expression of patients with the D1152H CFTR mutation.

BACKGROUND: Discordant results were reported on the clinical expression of subjects bearing the D1152H CFTR mutation, and also for the small number of cases reported so far. METHODS: A retrospective review of clinical, genetic and biochemical data was performed from individuals homozygous or compound heterozygous for the D1152H mutation followed in 12 Italian cystic fibrosis (CF) centers. RESULTS: 89 subjects carrying at least D1152H on one allele were identified. 7 homozygous patients had very mild clinical expression. Over half of the 74 subjects compound heterozygous for D1152H and a I-II-III class mutation had borderline or pathological sweat test and respiratory or gastrointestinal symptoms; one third had pulmonary bacteria colonization and 10/74 cases had complications (i.e. diabetes, allergic bronchopulmonary aspergillosis, and hemoptysis). However, their clinical expression was less severe as compared to a group of CF patients homozygous for the F508del mutation. Finally, 8 subjects compound heterozygous for D1152H and a IV-V class mutation showed very mild disease. CONCLUSIONS: The natural history of subjects bearing the D1152H mutation is widely heterogeneous and is influenced by the mutation in trans.

Recurrent pulmonary exacerbations are associated with low fat free mass and low bone mineral density in young adults with cystic fibrosis.

BACKGROUND: In cystic fibrosis (CF), systemic inflammation and pulmonary infections sustain a catabolic response leading to fat free mass (FFM) depletion. OBJECTIVES: To investigate the association between recurrent pulmonary exacerbations and alteration in body composition in young adults with CF. METHODS: In a retrospective study we collected body composition data, obtained by DXA scan, on 85 young adults with CF (44 males, mean age 23±4years). Whole body and appendicular FFM were divided by height squared to obtain FFM indices (FFMI). Number of pulmonary exacerbations occurred in the year preceding DXA scan were computed and patients were defined as frequent exacerbators if they experienced more than 2 pulmonary exacerbations/year. Body composition data were compared between frequent and infrequent exacerbators. RESULTS: Male patients classified as frequent exacerbators had lower total body bone mineral density (Z-score -1.44±1.22 vs. -0.66±0.92, P=0.033), whole body FFMI (18.0±1.9kg/m(2) vs. 19.3±1.4kg/m(2), P=0.024) and appendicular FFMI (7.8±1.0kg/m(2) vs. 8.8±0.8kg/m(2)P=0.004) compared to infrequent exacerbators. The reduced FFM found in frequent exacerbators was not uniformly distributed and involved mainly appendicular FFM (mean difference: -11% compared to infrequent exacerbators, P=0.016), whereas trunk FFM was not significantly affected by pulmonary exacerbations (mean difference -3% compared to infrequent exacerbators, P=0.34). These differences were not found in female patients. CONCLUSIONS: Recurrent pulmonary exacerbations are associated with reduced appendicular FFM and bone mineral density in young male adults with CF. The gender-dependent relationship between pulmonary exacerbations and body composition alteration needs to be further investigated.