The clinical features and impact of SARS-CoV-2/COVID-19 infection in children with Cystic Fibrosis (CF): A Qatari experience.

BACKGROUND: SARS-CoV-2 in children with cystic fibrosis (CF) has been reported to cause mild illness without pre-existing severe lung disease. This review described the clinical presentation and course of COVID-19 infection in children with CF in Qatar. METHODS: The pediatric CF registry of 51 patients in Qatar was reviewed for COVID-19 cases from February 2020 to February 2022. Demographics, vaccination status, symptoms, and course were reviewed. Data were expressed as median, range, frequencies, and percentages. RESULTS: The study included eight patients with CF below 18 years of age infected with COVID-19. The incidence of COVID-19 in children with CF was 15.7%. The median age was 11 (2-18) years. Half of the cohort were males. Seven patients were pancreatic sufficient (I1234V mutation), and one was pancreatic insufficient (3129del4 mutation). The median baseline FEV1 was 91 (78-107%) predicted. None had received CFTR modulators or undergone a lung transplant. Three patients were vaccinated before their infections. Two of them were asymptomatic. Six patients (75%) had a cough and flu-like symptoms. Three patients had a fever. Two patients were hospitalized due to pulmonary exacerbation; both had mild CF-lung disease. None required respiratory support. CONCLUSION: We report a favorable outcome of COVID-19 infection in children with CF, similar to published international studies. Our findings are attributable to the community-dominant milder CFTR mutation, precautionary measures, and causative COVID-19 strain. More longitudinal data are needed to study these factors as potential protective mechanisms.

Vitamin D intake, serum 25-hydroxy vitamin D and pulmonary function in paediatric patients with cystic fibrosis: a longitudinal approach.

Pancreatic-insufficient children with cystic fibrosis (CF) receive age-group-specific vitamin D supplementation according to international CF nutritional guidelines. The potential advantageous immunomodulatory effect of serum 25-hydroxy vitamin D (25(OH)D) on pulmonary function (PF) is yet to be established and is complicated by CF-related vitamin D malabsorption. We aimed to assess whether current recommendations are optimal for preventing deficiencies and whether higher serum 25(OH)D levels have long-term beneficial effects on PF. We examined the longitudinal relationship between vitamin D intake, serum 25(OH)D and PF in 190 CF children during a 4-year follow-up period. We found a significant relationship between total vitamin D intake and serum 25(OH)D (ß = 0·02; 95 % CI 0·01, 0·03; P = 0·000). However, serum 25(OH)D decreased with increasing body weight (ß = -0·79; 95 % CI -1·28, -0·29; P = 0·002). Furthermore, we observed a significant relationship between serum 25(OH)D and forced expiratory volume in 1 s (ß = 0·056; 95 % CI 0·01, 0·102; P = 0·018) and forced vital capacity (ß = 0·045; 95 % CI 0·008, 0·082; P = 0·017). In the present large study sample, vitamin D intake is associated with serum 25(OH)D levels, and adequate serum 25(OH)D levels may contribute to the preservation of PF in children with CF. Furthermore, to maintain adequate levels of serum 25(OH)D, vitamin D supplementation should increase with increasing body weight. Adjustments of the international CF nutritional guidelines, in which vitamin D supplementation increases with increasing weight, should be considered.

The importance of prenatal diagnosis for the surgical strategy of giant cystic meconium peritonitis: A case report.

Background: Giant cystic meconium peritonitis (MP) is a relatively rare entity. Prompt surgical treatment is required to manage the underlying etiology and reestablish the continuity of the intestines. Despite perinatal and postoperative care improvements, the overall mortality rate is still relatively high. We reported a giant cystic MP that was recognized using antenatal sonography (US). It was successfully treated with primary anastomosis. Case presentation: We presented a female newborn with a chief complaint of abdominal mass. The prenatal sonography showed an intraabdominal cyst at the 28th week of gestation. She was born at the gestational age of 38 weeks via vaginal delivery from a primigravid mother without complications, with a birth weight of 3275 g. Elective surgery was performed at the age of eight days, and a calcified 10 cm cyst was revealed along with severe adhesions. The cyst was found to communicate with the ileum located 30 cm proximal from the ileocecal junction. No malrotation and volvulus were found. The cyst and a portion of the ileum were resected, followed by a primary end-to-end anastomosis. Pathologic examination showed necrotic tissue lined with epithelial tissue with microcalcifications containing bilirubin pigments, consistent with cystic MP. The patient has uneventfully discharged on postoperative day 17. The patient has normal growth and development, except for delayed walking, at the last follow-up of two years of age. Conclusion: Giant cystic MP is a rare disorder that can be detected early using the antenatal US. Our case highlights the importance of early diagnosis for giant cystic MP using the antenatal US leads to prompt surgical treatment and a more favorable prognosis.

Long-term follow-up and liver outcomes in children with cystic fibrosis and nodular liver on ultrasound in a multi-center study.

BACKGROUND: Nodular liver (NOD) in cystic fibrosis (CF) suggests advanced CF liver disease (aCFLD); little is known about progression of liver disease (LD) after detection of sonographic NOD. METHODS: Clinical, laboratory, and ultrasound (US) data from Prediction by Ultrasound of the Risk of Hepatic Cirrhosis in CFLD Study participants with NOD at screening or follow-up were compared with normal (NL). Linear mixed effects models were used for risk factors for LD progression and Kaplan-Meier estimator for time-to-event. RESULTS: 54 children with NOD (22 screening, 32 follow-up) and 112 NL were evaluated. Baseline (BL) and trajectory of forced expiratory volume, forced vital capacity, height/BMI z-scores were similar in NOD vs NL. Platelets were lower in NOD at BL (250 vs 331×103/microL; p < 0.001) and decreased by 8600/year vs 2500 in NL. Mean AST to Platelet Ratio Index (1.1 vs 0.4; p < 0.001), Fibrosis-4 Index (0.4 vs 0.2, p < 0.001), and spleen size z-score (SSZ) [1.5 vs 0.02; p < 0.001] were higher in NOD at BL; SSZ increased by 0.5 unit/year in NOD vs 0.1 unit/year in NL. Median liver stiffness (LSM) by transient elastography was higher in NOD (8.2 kPa, IQR 6-11.8) vs NL (5.3, 4.2-7, p < 0.0001). Over 6.3 years follow-up (1.3-10.3), 6 NOD had esophageal varices (cumulative incidence in 10 years: 20%; 95% CI: 0.0%, 40.0%), 2 had variceal bleeding, and 2 underwent liver transplantation; none had ascites or hepatic encephalopathy. No NL experienced liver-related events. CONCLUSIONS: NOD developed clinically evident portal hypertension faster than NL without worse growth or lung disease.

Clinical efficacy of elexacaftor-tezacaftor-ivacaftor in an adolescent with homozygous G85E cystic fibrosis.

Elexacaftor-tezacaftor-ivacaftor (ELX/TEZ/IVA) is a triple combination drug therapy approved for individuals with cystic fibrosis (CF) who possess at least one copy of the F508del cystic fibrosis transmembrane conductance regulator (CFTR) variant. ELX/TEZ/IVA improves lung function and decreases the frequency of CF exacerbations in clinical studies, which has led to investigation of this therapy on rare CFTR variants. Rare mutations have limited research publications; therefore, reporting outcomes is critical to expanding knowledge and understanding of therapeutic efficacy. This case highlights a CF adolescent homozygous for the G85E CFTR variant who had resolution of chronic respiratory symptoms after initiating ELX/TEZ/IVA.

Bone metabolism and incretin hormones following glucose ingestion in young adults with pancreatic insufficient cystic fibrosis.

Background: Gut-derived incretin hormones, including glucose-dependent insulinotropic peptide (GIP) and glucagon-like peptide 1 (GLP-1), regulate post-prandial glucose metabolism by promoting insulin production. GIP, GLP-1, and insulin contribute to the acute bone anti-resorptive effect of macronutrient ingestion by modifying bone turnover. Cystic fibrosis (CF) is associated with exocrine pancreatic insufficiency (PI), which perturbs the incretin response. Cross-talk between the gut and bone ("gut-bone axis") has not yet been studied in PI-CF. The objectives of this study were to assess changes in biomarkers of bone metabolism during oral glucose tolerance testing (OGTT) and to test associations between incretins and biomarkers of bone metabolism in individuals with PI-CF. Methods: We performed a secondary analysis of previously acquired blood specimens from multi-sample OGTT from individuals with PI-CF ages 14-30 years (n = 23). Changes in insulin, incretins, and biomarkers of bone resorption (C-terminal telopeptide of type 1 collagen [CTX]) and formation (procollagen type I N-terminal propeptide [P1NP]) during OGTT were computed. Results: CTX decreased by 32% by min 120 of OGTT (P < 0.001), but P1NP was unchanged. Increases in GIP from 0 to 30 mins (rho = -0.48, P = 0.03) and decreases in GIP from 30 to 120 mins (rho = 0.62, P = 0.002) correlated with decreases in CTX from mins 0-120. Changes in GLP-1 and insulin were not correlated with changes in CTX, and changes in incretins and insulin were not correlated with changes in P1NP. Conclusions: Intact GIP response was correlated with the bone anti-resorptive effect of glucose ingestion, represented by a decrease in CTX. Since incretin hormones might contribute to development of diabetes and bone disease in CF, the "gut-bone axis" warrants further attention in CF during the years surrounding peak bone mass attainment.

Liver disease in cystic fibrosis patients in a tertiary care center in Saudi Arabia.

Background: Internationally, Cystic fibrosis-associated liver disease (CFLD) is considered the third leading cause of death, following lung disease and transplantation complications. Aims: To identify the prevalence of CFLD in cystic fibrosis (CF) patients. Methodology: A retrospective chart review for all patients with CF liver disease from a tertiary care center. Result: A total of 341 CF patients were included. The mean age at the diagnosis of liver disease is 13.5 (7.6) years.The first elevated ALT was reported in 190/341 patients (56%), elevated AST in 124 patients (36%), elevated alkaline phosphatase (ALP) in 166 patients (49.1%), elevated GGT in 57 patients (23%), and elevated bilirubin in 24 patients (7%). There was an improvement of the liver enzyme values during the follow-up period, P-value = (<0.05).Ultrasound liver assessments were performed in 258/341 patients (75.7%). One hundred and twelve patients (43%) had abnormal findings. In 14 patients (5.4%), assessment exhibited advanced liver disease (liver cirrhosis and periportal fibrosis). Out of 190 patients, who were given ursodeoxycholic acid for elevated liver enzymes, 180 (94.7%) exhibited improvement. One patient underwent liver transplant at the age of 12. Four patients were submitted for liver biopsy; periportal fibrosis was observed in 4 patients (1.6%), and liver cirrhosis by ultrasound (US) in 10 patients (4%). Conclusion: Patients with CF should be screened early for liver enzymes, and should undergo the US study to detect liver disease at early stages and to prevent its progression.

Bone accrual and structural changes over one year in youth with cystic fibrosis.

Background: Pediatric bone accrual governs peak bone mass and strength. Longitudinal studies of bone health in youth with cystic fibrosis (CF) may provide insight into CF-related bone disease (CFBD), a prevalent co-morbidity in adults with CF. Methods: This one-year longitudinal study of youth with pancreatic insufficient CF, enrolled in a nutrition intervention study [n = 62 (36 M/26F)] 1) examined dual-energy x-ray absorptiometry (DXA)-defined lumbar spine (LS) and total body less head (TBLH) bone accrual and 2) compared their changes in peripheral quantitative computed tomography (pQCT) cortical and trabecular tibial bone density and geometry to those of a healthy reference group [n = 143 (68 M/75F)].Main outcome measures were 1) DXA: lumbar spine areal bone mineral density (LSaBMD) and total body less head bone mineral content (TBLH-BMC), sex- and pubertal status-specific, height velocity (HV)-adjusted or HV and lean body mass velocity (HV-LBMV)-adjusted annualized velocity-Z scores and 2) pQCT: age, sex, pubertal status and, when appropriate, tibial length adjusted Z-scores for bone architecture measures.DXA velocity-Z were compared to expected mean of 0 and correlations with clinical parameters (age, BMI-Z and FEV1%-predicted) tested. Within-subject comparisons of HV-adjusted and LBMV-HV-adjusted DXA velocity-Z were conducted in CF.pQCT Z-scores were compared between the two groups over one year using longitudinal models. Longitudinal relationships between measures of bone health and clinical parameters (age, BMI-Z and FEV1%-predicted) were examined in individuals with CF. Results: DXA velocity-Z were higher than normal in females (p < 0.05) but not males with CF. HV-adjusted and LBMV-HV-adjusted velocity-Z did not differ for LSaBMD or TBLH-BMC.In males with CF, both HV-adjusted and LBMV-HV-adjusted LSaBMD velocity-Z scores correlated negatively with age (HV rho: -0.35; p = 0.045 and LBMV-HV rho: -0.47; p = 0.0046). In males with CF BMI-Z correlated positively with HV-adjusted LSaBMD velocity-Z (rho: 0.37; p = 0.034), but this relationship did not persist for LBMV-HV (rho: 0.14; p = 0.42). In females with CF, no correlations between LSaBMD velocity-Z scores and age or BMI-Z were found (all p > 0.05). No correlations between LSaBMD velocity-Z scores and FEV1%-predicted were seen in either sex (all p > 0.12). TBLH-BMC velocity Z-scores were not correlated with clinical parameters in either sex (all p > 0.1).At baseline, multiple pQCT parameters were lower in CF (p < 0.05). pQCT Z-scores did not differ between baseline and one-year in either CF or reference group. In a longitudinal model comparing pQCT-Z changes in CF and reference, multiple pQCT-Z outcomes remained lower in CF, but the changes in parameters did not differ in CF vs reference (all p > 0.26). Lower pQCT outcomes in CF were largely restricted to males (CF group*female sex interaction beta coefficients > 0). In this combined longitudinal model, of both CF and reference, BMI-Z was positively associated with pQCT-Z parameters(p < 0.001).Multiple pQCT-Z outcomes positively correlated with both BMI-Z and FEV1%-predicted in males with CF, and with FEV1%-predicted in females with CF (p < 0.05). Age was negatively associated with section modulus (p = 0.001) in males and with cortical density-Z in females (p < 0.001). Conclusions: With improved longevity, bone health in CF is of increasing importance. On average, bone accrual was preserved in youth with CF, and while deficits in bone geometry and strength were found, these deficits did not worsen over the one-year study. Lower LS bone accrual with increasing age suggests emerging adulthood is a period of vulnerability in CF while the role of LBM in bone health is underscored by the lack of relationship between LBMV-adjusted accrual and BMI. These findings may be useful in targeting screening practices and interventions.

Cystic fibrosis-related diabetes: Prevalence, screening, and diagnosis.

Cystic fibrosis-related diabetes (CFRD) is the most common comorbidity in patients with cystic fibrosis (CF). Prevalence of CFRD increases with age and is greater with severe mutations. Other risk factors associated with CFRD are female sex, pancreatic insufficiency, liver disease, need for gastrostomy tube feedings, history of bronchopulmonary aspergillosis, and poor pulmonary function. CFRD is related to worse clinical outcomes and increased mortality. Early diagnosis and treatment have been shown to improve clinical outcomes. Screening for CFRD is recommended with an annual oral glucose tolerance test (OGTT) starting at age 10 years. Diagnosis of CFRD is made by standard American Diabetes Association (ADA) criteria during baseline health. CFRD can also be diagnosed in individuals with CF during acute illness, while on enteral feeds, and after transplant. In this review we will discuss the epidemiology of CFRD and provide an overview of the advantages and pitfalls of current screening and diagnostic tests for CFRD.

Use of estrogen supplementation is associated with higher quality of life scores in women with cystic fibrosis.

The association of estrogen supplementation use and quality of life in women with cystic fibrosis (CF) is not well characterized. In this cross-sectional study, women with CF completed quality of life questionnaires during a routine CF clinic visit. The use of estrogen supplementation was associated with higher quality of life scores in all domains of the CF questionnaire-revised (CFQ-R) and was significant in the role limitations and respiratory domains. Most participants who were not currently using estrogen supplementation had previously used estrogen supplementation. Most participants had used estrogen to regulate menses, prevent pregnancy and control symptoms around menses. Use of estrogen supplementation was not associated with differences in life-space mobility or screening for sexual dysfunction. This is the largest study to date investigating the association of estrogen supplementation and quality of life in women with CF. Prospective randomized studies are needed to clarify the association of estrogen supplementation and quality of life in women with CF.

Case of recurrent Achromobacter xylosoxidans bacteraemia and PICC (peripherally-inserted central catheter) line infection in an immunocompromised patient.

BACKGROUND: This report describes recurrent A. xylosoxidans bloodstream and PICC (peripherally-inserted central catheter) line infection in an immunocompromised patient. PRESENTATION OF CASE: A 64-year-old female with acute promyelocytic leukaemia presented during a non-neutropenic febrile episode, and A. xylosoxidans was isolated from multiple PICC and peripheral blood cultures, and from the tip of the line on removal. The patient was treated with meropenem and a new PICC line was inserted after sterile blood cultures. Six weeks later, she represented with A. xylosoxidans from multiple cultures from the line. She was treated with piperacillin-tazobactam and the line was removed. There was no evidence of deep-seated infection. Further discussion revealed that the patient was using a sponge to clean, and a sleeve to cover her PICC-line while bathing. A. xylosoxidans was cultured from both the sponge and the swab. Whole Genome Sequencing performed on two blood culture isolated and both environmental isolates confirmed all four isolates were indistinguishable. The patient was advised not to use the sponge/sleeve in future and we have incorporated specific advice in this regard into our patient information. DISCUSSION: Achromobacter xylosoxidans is an aerobic, non-lactose fermenting gram-negative bacillus usually considered an opportunistic pathogen. It is associated with infection in immunocompromised patients, and is an emerging pathogen in catheter-related infections, sometimes associated with contaminated water. CONCLUSION: This case of recurrent A. xylosoxidans line infection highlights diagnostic and management challenges associated with catheter-related infections. Treatment is challenging because of intrinsic and acquired resistance mechanisms. Empiric treatment with anti-pseudomonal penicillins or carbapenems with line removal is typically required.

An update on methods for assessing bone quality and health in Cystic fibrosis.

With increasing life expectancy in people with Cystic fibrosis (CF), the focus of clinical care has shifted to management and prevention of non-pulmonary comorbidities. CF related bone disease, defined by low bone mineral density (BMD), is prevalent across all age groups and acknowledges the increased fractures rates that negatively impact lung function and quality of life. Dual energy X-ray absorptiometry (DXA) measurement of bone mineral content (BMC) and "areal" BMD (aBMD) is recommended for identifying and monitoring bone health in children and adults due to its low cost, low radiation exposure, and widespread availability. Recent studies in children and adolescents with chronic illness focus on adjustment of BMC and aBMD measurements for height due to the effects of short stature and delayed maturation on bone size. Expanded reference databases for alternate imaging sites such as the ultradistal radius and hip present opportunities for research and long-term monitoring. As the two-dimensional nature of DXA imposes limitations, we highlight other imaging modalities including peripheral quantitative computed tomography QCT (pQCT), magnetic resonance imaging, and quantitative ultrasound (QUS). These tools, while primarily used in a research setting, can impart information on true volumetric bone density and bone microarchitecture as well as contribute to fracture assessment and prediction. Due to the high morbidity and mortality associated with vertebral and hip fracture, we will present on vertebral fracture assessment (VFA) in both children and adults as well as applied analyses including hip structural analysis (HSA), trabecular bone score (TBS), and fracture risk assessment (FRAX) for high risk groups. Questions remain on the future clinical applicability and accessibility of these assessment and prediction tools, longitudinal monitoring through adolescence and adulthood, and how outcome measures may guide bone modifying therapies.

Obesity in cystic fibrosis.

The prevalence of obesity in patients with cystic fibrosis (CF) is increasing and around one-third of adults with CF are now overweight or obese. The causes of excess weight gain in CF are likely multifactorial, including: adherence to the high-fat legacy diet, reduced exercise tolerance, therapeutic advances, and general population trends. Increased weight has generally been considered favorable in CF, correlating with improved pulmonary function and survival. While the optimal BMI for overall health in CF is unknown, most studies demonstrate minimal improvement in pulmonary function when BMI exceeds 30 kg/m2. Dyslipidemia and cardiovascular disease are important co-morbidities of obesity in the general population, but are uncommon in CF. In people with CF, obesity is associated with hypertension and higher cholesterol levels. With longer life expectancy and rising obesity rates, there may be an increase in cardiovascular disease among people with CF in coming years. Overweight CF patients are more likely to be insulin resistant, taking on features of type 2 diabetes. Treating obesity in people with CF requires carefully weighing the metabolic risks of overnutrition with the impact of low or falling BMI on lung function. This article describes current knowledge on the epidemiology, causes, consequence, and treatment of obesity in people with CF.

Congenital unilateral absence of the vas deferens with ipsilateral renal agenesis encountered during laparoscopic totally extraperitoneal inguinal hernia repair in an adult patient: A case report.

INTRODUCTION AND IMPORTANCE: Congenital unilateral absence of the vas deferens and ipsilateral renal agenesis is a rare condition in which the vas deferens is absent unilateral due to a congenital anomaly. This report illustrates the clinical relevance of absence of the vasa deferentia. This occurs either unilateral, which is associated with renal anomalies, or bilateral which leads to azoospermia and often has a genetic link to cystic fibrosis. CASE PRESENTATION: We report the first incidental finding of congenital unilateral absence of the vas deferens and ipsilateral renal agenesis during bilateral laparoscopic totally extraperitoneal inguinal hernia repair in a 70 year old patient. CONCLUSION: Surgeons who encounter unilateral absence of the vas deferens should assess bilateral absence of the vasa deferentia by palpation in adult patients or by laparoscopic exploration of the contralateral inguinal canal in pediatric patients. Renal ultrasonography should be performed in all patients to assess renal anomalies. Genetic counselling is advised when absence of the vasa deferentia is present bilaterally of unilaterally with associated infertility.

Outcome of lung transplantation in cystic fibrosis patients with severe asymmetric chest cavities.

Objective: A small but relevant proportion of patients with cystic fibrosis develop severely asymmetric chest cavities during the course of their disease. For these patients, the best surgical approach for lung transplantation (LTx) and optimal size matching strategies are controversial. Methods: All cystic fibrosis patients with asymmetric chest cavities who underwent LTx at the Medical University of Vienna between 2003 and 2017 were identified (n = 13). Patients were grouped according to different surgical strategies: unilateral full-size and contralateral lobar transplantation (n = 4), standard double LTx after mobilization/repositioning of the mediastinum (n = 3), oversized single LTx followed by pneumonectomy on the smaller contralateral side (n = 4), and single LTx after a remote contralateral pneumonectomy (n = 2). Results: Compared with cystic fibrosis patients with symmetric chests (n = 276, control group), the perioperative management of patients with asymmetric chests was often more complicated. Consequently, 90-day mortality was heightened (23.1% vs 6.5%). Despite this, long-term survival was good with a 5-year survival rate of 69% compared with 78%. Of note, outcome seemed superior for patients who surgery was undertaken with a bilateral compared with a unilateral approach. Conclusions: Severely asymmetric chest cavities present challenges in regard to the surgical strategy, size matching, and postoperative management. However, in carefully selected patients, LTx provides an adequate long-term outcome.

Delayed hepatic necrosis in a cystic fibrosis patient taking Elexacaftor/Tezacaftor/Ivacaftor (Kaftrio).

The introduction of Cystic Fibrosis Trans Regulatory modulator (CFTRm) drugs has seen a transformation in Cystic Fibrosis (CF) treatment. This has led to a significant improvement in lung function and quality of life with the potential for a real impact on life expectancy. Transient mild to moderate hepatic transaminitis is a well-known side effect of CFTRm drugs, which often improves on cessation and may not recur following the re-institution of the drug. We describe a case of transaminitis developing nine months after the initiation of Kaftrio, which progressed to liver necrosis despite stopping Kaftrio and took many months to resolve. The patient had experienced significant improvement in lung function and overall health while on Kaftrio and deteriorated when it was stopped. He was keen to restart; however, Kaftrio was not reinstated due to the potential risk of acute liver failure.

A Clinician's guide to vitamin D supplementation for patients with cystic fibrosis.

Vitamin D deficiency is common in the general population, and even more so in patients with cystic fibrosis. Deficiency is exacerbated in cystic fibrosis patients because of a myriad of causes including malabsorption, decreased fat mass, reduced 25-hydroxylation of vitamin D, reduced exposure to sunlight, decreased vitamin D binding protein, and exposure to drugs that increase catabolism. In turn, vitamin D deficiency can contribute to poor bone health. Additionally, it may contribute to pulmonary decline in the form of worsening pulmonary function, increased colonization with pathogens, and increased pulmonary exacerbation. Because vitamin D deficiency is correlated with negative clinical effects in multiple organ systems of patients with cystic fibrosis, it is important to screen for and treat deficiency in these patients. The Cystic Fibrosis Foundation has issued guidelines for the treatment of vitamin D deficiency, targeting serum levels of 25-hydroxyvitamin D of at least 30 ng/ml. The guidelines offer age-specific escalating dose regimens depending on serum vitamin D levels, with monitoring at 12- week intervals after changing therapy. They address the literature on alternative vitamin D sources, such as UV lamps, ideal formulations (cholecalciferol in preference to ergocalciferol), and optimal vehicles of administration. Despite these detailed recommendations, most centers are still unable to achieve in-target serum vitamin D levels for many of their patients. Future research examining ideal treatment regimens to achieve serum targets and maximize clinical effects are needed. Moreover, it is unknown whether vitamin D sufficiency will be easier to achieve on new triple therapy cystic fibrosis drug combinations, and how these drugs will contribute to vitamin D-related clinical outcomes.

Internet and smartphone-based ecological momentary assessment and personalized advice (PROfeel) in adolescents with chronic conditions: A feasibility study.

OBJECTIVE: Growing up with a chronic disease comes with challenges, such as coping with fatigue. Many adolescents are severely fatigued, though its associated factors exhibit considerable interpersonal and longitudinal variation. We assessed whether PROfeel, a combination of a smartphone-based ecological momentary assessment (EMA) method using the internet, followed by a face-to-face dialogue and personalized advice for improvement of symptoms or tailor treatment based on a dynamic network analysis report, was feasible and useful. STUDY DESIGN: Feasibility study in fatigued outpatient adolescents 12-18 years of age with cystic fibrosis, autoimmune disease, post-cancer treatment, or with medically unexplained fatigue. Participants were assessed at baseline to personalize EMA questions. EMA was conducted via smartphone notifications five times per day for approximately six weeks. Hereby, data was collected via the internet. The EMA results were translated into a personalized report, discussed with the participant, and subsequently translated into a personalized advice. Afterwards, semi-structured interviews on feasibility and usefulness were held. RESULTS: Fifty-seven adolescents were assessed (mean age 16.2 y ± 1.6, 16% male). Adolescents deemed the smartphone-based EMA feasible, with the app being used for an average of 49 days. Forty-two percent of the notifications were answered and 85% of the participants would recommend the app to other adolescents. The personalized report was deemed useful and comprehensible and 95% recognized themselves in the personalized report, with 64% rating improved insight in their symptoms and subsequent steps towards an approach to reduce one's fatigue as good or very good. CONCLUSIONS: PROfeel was found to be highly feasible and useful for fatigued adolescents with a chronic condition. This innovative method has clinical relevance through bringing a patient's daily life into the clinical conversation.

Impaired glucose tolerance and indeterminate glycemia in cystic fibrosis.

Oral glucose tolerance testing (OGTT) is the primary method to screen for and diagnose cystic fibrosis-related diabetes (CFRD). Diagnostic thresholds as currently defined are based on microvascular complications seen in type 2 diabetes. Abnormal glucose tolerance (AGT) refers to OGTT glucose elevations outside the normal range and encompasses both impaired and indeterminate glucose tolerance. Current guidelines define impaired glucose tolerance (IGT) as a 2-hour glucose of 140-199 mg/dL (7.8-11 mmol/L) and indeterminate glucose tolerance (INDET) as any mid-OGTT glucose ≥ 200 mg/dL (11.1 mmol/L) with a normal fasting and 2 h glucose. There is growing evidence that AGT also has associations with CF-centered outcomes including pulmonary decline, hospitalizations, and weight loss. Here we aim to review the historical emergence of glucose tolerance testing, review relevance to risk stratification for CFRD, discuss alternate cutoffs for identifying AGT earlier, and highlight the need for larger, future studies to inform our understanding of the implications of IGT and INDET on CF health.

Body composition in individuals with cystic fibrosis.

Because nutritional status is intimately linked with pulmonary function and survival, nutrition has been at the mainstay of cystic fibrosis (CF) care. Body Mass Index (BMI) is traditionally used to define nutritional status because of the ease with which it can be calculated, but it has a number of limitations including its inability to differentiate fat mass (FM) from lean body mass (LBM), the latter thought to confer health advantage. A number of tools are available to quantify body composition including dual-energy x-ray absorptiometry (DXA), bioelectrical impedance, MRI, CT, air displacement plethysmography, and stable isotopes, and these have been used to varying degrees in studies of CF. In CF, LBM tends to be lower for a given BMI, particularly at lower BMI. In adults, lower fat-free mass (FFM) correlates with greater CF disease severity, lower pulmonary function and higher inflammatory markers. FFM is also positively associated with greater bone mineral density, while greater FM is associated with greater loss of lumbar spine bone mineral density over 2 years. In youth, LBM is positively associated with pulmonary function. The predictive value of body composition for functional and clinical outcomes and the role of improving LBM on these outcomes remain undefined. With improvements in BMI accompanying highly-effective modulator therapy, closer evaluations of body composition may inform risk for more traditional, non-CF adult outcomes in CF.