Computed tomography in cystic fibrosis lung disease: a focus on radiation exposure

Thoracic computed tomography (CT) is the imaging reference method in the diagnosis, assessment and management of lung disease. In the setting of cystic fibrosis (CF), CT demonstrates increased sensitivity compared with pulmonary function tests and chest radiography, and findings correlate with clinical outcomes. Better understanding of the aetiology of CF lung disease indicates that even asymptomatic infants with CF can have irreversible pulmonary pathology. Surveillance and early diagnosis of lung disease in CF are important to preserve lung parenchyma and to optimise long-term outcomes. CF is associated with increased cumulative radiation exposure due to the requirement for repeated imaging from a young age. Radiation dose optimisation, important for the safe use of CT in children with CF, is best achieved in a team environment where paediatric radiologists work closely with paediatric respiratory physicians, physicists and radiography technicians to achieve the best patient outcomes. Despite the radiation doses incurred, CT remains a vital imaging tool in children with CF. Radiologists with special interests in CT dose optimisation and respiratory disease are key to the appropriate use of CT in paediatric imaging. Paediatric radiologists strive to minimise radiation dose to children whilst providing the best possible assessment of lung disease.

Neonatal screening programme for CF: Results from the Irish Comparative Outcomes Study (ICOS)

The introduction of NBS in Ireland in July 2011, provided a unique opportunity to investigate clinical outcomes using a comparative historical cohort study. Clinical cohort: children clinically diagnosed with CF born 1 July 2008 to 30 June 2011, and NBS cohort: children diagnosed with CF through NBS born 1 July 2011 to 30 June 2016. Clinical data were collected from the CF Registry of Ireland, medical charts, and data on weight/height before diagnosis from public health nurses and family doctors. SPSS was used for analysis. A total of 232 patients were recruited (response 93%) (93 clinically diagnosed, 139 NBS-detected). Following exclusions of meconium ileus (MI) (40), diagnosis outside Ireland (4), and being designated as CFSPID (2), a total of 77 clinically diagnosed patients and 109 NBS detected children were included in analysis. Over half were homozygous for F508del mutation. Being clinically diagnosed was independently associated with hospitalization for infective exacerbation of CF < 36 months (OR, 2.80; 95%CI 1.24-6.29). Diagnosis to first acquisition of Pseudomonas aeruginosa was significantly longer in NBS than clinically detected; from birth there was no significant difference. Weight and length/height were significantly greater in NBS cohort at 6 and 12 months. We provide evidence of improved growth, reduced hospitalization for acute exacerbations, and delayed P. aeruginosa acquisition (from diagnosis) to age 3 for the NBS cohort. Screening practices likely account for the non-significant difference in P. aeruginosa acquisition from birth.

Improvements in Clinical Outcomes in Children with Cystic Fibrosis aged Six and 16 years

Aims Our aim was to assess if outcomes for cystic fibrosis (CF) patients at six & sixteen years of age have improved in the last 17 years looking at FEV1, BMI and death. Methods A retrospective observational study using a prospectively maintained database of CF patients at Cork University Hospital. Results 84 patients were included in the 16-year-old data and 89 patients were included in the six-year-old data. The mean FEV1 and BMI (16 years) for the 2002-2007 group was 72.9±21.0% and 18.9±2.53 respectively, 2008-2013 group was 75.4±27.2% and 19.8±2.7 and for the 2014-2018 group was 95.2±16.0% and 22.9±4.1. The percentage of patients (16 years) with chronic pseudomonas status was 37.9% (11/30) in the 2002-2007 group, 51.6 % (16/31) in the 2008-2013 group and 4.2% (1/24) in the 2014-2018 group. The relationship between FEV1 and FVC with BMI remained significant in multivariate analysis (P <0.001). The mean FEV1 (six years) for the 2002-2007 group was 90.7±16.1%, 2008-2013 group was 99.3±17.9% and for the 2014-2018 group was 100.9±15.8%. Conclusions Improvements in FEV1 and BMI aged six and 16 years are notable as well as a significant decline in the number of patients with chronic pseudomonas.

Juvenile systemic lupus erythematosus presenting as pancarditis

BACKGROUND

Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with marked variation in its clinical presentation. Juvenile SLE (jSLE) accounts for 15-20% of all cases and is diagnosed when SLE manifests before 18 years of age. Pancarditis is a rare complication of SLE, regardless of age of disease onset.

CASE PRESENTATION

We report a case of jSLE in a 15 year old Caucasian female presenting with an acute episode of pancarditis and multiorgan dysfunction who was successfully treated with systemic corticosteroids and cyclophosphamide.

CONCLUSION

Pancarditis can be a presenting feature of jSLE which was previously unreported. A high index of suspicion for severe cardiac involvement is required at all stages of disease.

CORK Study in Cystic Fibrosis: Sustained Improvements in Ultra-Low-Dose Chest CT Scores After CFTR Modulation With Ivacaftor

BACKGROUND

Ivacaftor produces significant clinical benefit in patients with cystic fibrosis (CF) with the G551D mutation. Prevalence of this mutation at the Cork CF Centre is 23%. This study assessed the impact of cystic fibrosis transmembrane conductance regulator modulation on multiple modalities of patient assessment.

METHODS

Thirty-three patients with the G551D mutation were assessed at baseline and prospectively every 3 months for 1 year after initiation of ivacaftor. Change in ultra-low-dose chest CT scans, blood inflammatory mediators, and the sputum microbiome were assessed.

RESULTS

Significant improvements in FEV₁, BMI, and sweat chloride levels were observed post-ivacaftor treatment. Improvement in ultra-low-dose CT imaging scores were observed after treatment, with significant mean reductions in total Bhalla score (P < .01), peribronchial thickening (P = .035), and extent of mucous plugging (P < .001). Reductions in circulating inflammatory markers, including interleukin (IL)-1β, IL-6, and IL-8 were demonstrated. There was a 30% reduction in the relative abundance of Pseudomonas species and an increase in the relative abundance of bacteria associated with more stable community structures. Posttreatment community richness increased significantly (P = .03).

CONCLUSIONS

Early and sustained improvements on ultra-low-dose CT scores suggest it may be a useful method of evaluating treatment response. It paralleled improvement in symptoms, circulating inflammatory markers, and changes in the lung microbiota.

Bile signalling promotes chronic respiratory infections and antibiotic tolerance

Despite aggressive antimicrobial therapy, many respiratory pathogens persist in the lung, underpinning the chronic inflammation and eventual lung decline that are characteristic of respiratory disease. Recently, bile acid aspiration has emerged as a major comorbidity associated with a range of lung diseases, shaping the lung microbiome and promoting colonisation by Pseudomonas aeruginosa in Cystic Fibrosis (CF) patients. In order to uncover the molecular mechanism through which bile modulates the respiratory microbiome, a combination of global transcriptomic and phenotypic analyses of the P. aeruginosa response to bile was undertaken. Bile responsive pathways responsible for virulence, adaptive metabolism, and redox control were identified, with macrolide and polymyxin antibiotic tolerance increased significantly in the presence of bile. Bile acids, and chenodeoxycholic acid (CDCA) in particular, elicited chronic biofilm behaviour in P. aeruginosa, while induction of the pro-inflammatory cytokine Interleukin-6 (IL-6) in lung epithelial cells by CDCA was Farnesoid X Receptor (FXR) dependent. Microbiome analysis of paediatric CF sputum samples demonstrated increased colonisation by P. aeruginosa and other Proteobacterial pathogens in bile aspirating compared to non-aspirating patients. Together, these data suggest that bile acid signalling is a leading trigger for the development of chronic phenotypes underlying the pathophysiology of chronic respiratory disease.

Molecular epidemiology of Mycobacterium abscessus complex isolates in Ireland

BACKGROUND

The Mycobacterium abscessus complex are the rapidly growing mycobacteria (RGM) most commonly causing lung disease, especially in cystic fibrosis (CF) patients. Ireland has the world's highest CF incidence. The molecular epidemiology of M. abscessus complex in Ireland is unreported.

METHODS

We performed rpoB gene sequencing and multi-locus sequence typing (MLST) on M. abscessus complex strains isolated from thirty-six patients in 2006-2012 (eighteen known CF patients).

RESULTS

Twenty-eight strains (78%) were M. abscessus subsp. abscessus, eight M. abscessus subsp. massiliense, none were M. abscessus subsp. bolletii. Sequence type 1 (ST1) and ST26 (M. abscessus subsp. abscessus) were commonest. Seven M. abscessus subsp. abscessus STs (25%) were novel (two with novel alleles). Seven M. abscessus subsp. massiliense STs were previously reported (88%), including two ST23, the globally successful clone. In 2012, of 552 CF patients screened, eleven were infected with M. abscessus complex strains (2%).

CONCLUSIONS

The most prevalent M. abscessus subsp. abscessus and M. abscessus subsp. massiliense strains in Ireland belong to widely-distributed STs, but there is evidence of high M. abscessus subsp. abscessus diversity.

Diagnosis and treatment of sleep related breathing disorders in children: 2007 to 2011

Sleep related breathing disorders (SRBD) have historically been under-recognised and under-treated. Obstructive sleep apnoea (OSA) affects approximately 3% of children. In line with the increased recognition of SRBD there has been an increase in demand for diagnostic services. We determined the awareness of SRBD amongst Irish paediatricians, examined the provision of sleep services to children throughout the country between 2007 and 2011 and audited diagnostic sleep services in a tertiary centre in 2011. Amongst respondents there was an awareness of SRBD but a poor understanding of diagnostic evaluation with 31/46 (67) referring to inappropriate services. There has been a sharp increase in both diagnostic sleep tests (433-1793 [414]) and in the use of non-invasive ventilation (NIV) (31-186 [627]) for treatment of SRBD between 2007 and 2011. Paediatric sleep services are organized in an ad-hoc manner nationally with significant service variation. The use of domiciliary overnight oximetry reduced the requirement for more formal polysomnography by 70%.

Reduced infant lung function, active smoking, and wheeze in 18-year-old individuals

IMPORTANCE This is the first study to link reduced lung function in early life, before the development of symptoms, to wheeze in 18-year-olds. Additionally, the study gives insight into factors other than reduced lung function that are also associated with persistent wheeze in young adults.

OBJECTIVE

To test the hypothesis that reduced lung function in early life is associated with increased risk for persistent wheeze at age 18 years.

DESIGN

Birth cohort study.

SETTING

Perth, Western Australia.

PARTICIPANTS

Individuals followed up from age 1 month to 18 years.

MAIN OUTCOME MEASURES

Maximal flow at functional residual capacity (V'maxFRC) was measured in 1-month-old infants who were followed up at ages 6, 12, and 18 years. Based on reported symptoms, individuals were categorized as having remittent wheeze, later-onset wheeze, persistent wheeze, and no wheeze. Smoking status was noted at age 18 years.

RESULTS

Of the 253 individuals originally recruited, 150 were followed up at age 18 years; 37 of the 150 had recent wheeze. Compared with the no-wheeze group (n = 96), persistent wheeze (n = 13) was independently associated with reduced percentage of predicted V'maxFRC (mean reduction, 43%; 95% CI, 13-74). Compared with the no-wheeze group, persistent wheeze was also associated with atopy in infancy (odds ratio = 7.1; 95% CI, 1.5-34.5), maternal asthma (odds ratio = 6.8; 95% CI, 1.4-32.3), and active smoking (odds ratio = 4.8; 95% CI, 1.0-21.3). When only wheeze at age 18 years was considered, reduced percentage of predicted V'maxFRC was associated with wheeze at age 18 years only among current smokers (P = .04).

CONCLUSIONS AND RELEVANCE

Wheeze persisting from ages 6 to 18 years is associated with multiple factors, including reduced infant lung function, infant-onset atopy, maternal asthma, and active smoking. Wheeze at age 18 years (regardless of previous wheeze status) is associated with active smoking, but only among those with reduced lung function in infancy. These findings give unique insight into the cause of obstructive airways disease in 18-year-olds, and follow-up of this cohort might be expected to further extend our understanding.

Drug induced aseptic meningitis caused by intravenous immunoglobulin therapy

Drug induced aseptic meningitis (DIAM) is an uncommon condition that can mimic infective conditions. DIAM has been recognized with various treatments including non-steroidal anti-inflammatory drugs, monoclonal antibodies and some antibiotics. We report a patient presenting with aseptic meningitis forty-eight hours after commencing a course of intravenous immunoglobulin (IVIG) treatment. It is important that physicians prescribing this medication are aware of this rare complication so the diagnosis can be made quickly and the patient is not exposed to unnecessary treatments.

Radiologic imaging in cystic fibrosis: cumulative effective dose and changing trends over 2 decades

OBJECTIVE

With the increasing life expectancy for patients with cystic fibrosis (CF), and a known predisposition to certain cancers, cumulative radiation exposure from radiologic imaging is of increasing significance. This study explores the estimated cumulative effective radiation dose over a 17-year period from radiologic procedures and changing trends of imaging modalities over this period.

METHODS

Estimated cumulative effective dose (CED) from all thoracic and extrathoracic imaging modalities and interventional radiology procedures for both adult and pediatric patients with CF, exclusively attending a nationally designated CF center between 1992-2009 for > 1 year, was determined. The study period was divided into three equal tertiles, and estimated CED attributable to all radiologic procedures was estimated for each tertile.

RESULTS

Two hundred thirty patients met inclusion criteria (2,240 person-years of follow-up; 5,596 radiologic procedures). CED was > 75 mSv for one patient (0.43%), 36 patients (15.6%) had a CED between 20 and 75 mSv, 56 patients (24.3%) had a CED between 5 and 20 mSv, and in 138 patients (60%) the CED was estimated to be between 0 and 5 mSv over the study period. The mean annual CED per patient increased consecutively from 0.39 mSv/y to 0.47 mSv/y to 1.67 mSv/y over the tertiles one to three of the study period, respectively (P < .001). Thoracic imaging accounted for 46.9% of the total CED and abdominopelvic imaging accounted for 42.9% of the CED, respectively. There was an associated 5.9-fold increase in the use of all CT scanning per patient (P < .001).

CONCLUSIONS

This study highlights the increasing exposure to ionizing radiation to patients with CF as a result of diagnostic imaging, primarily attributable to CT scanning. Increased awareness of CED and strategies to reduce this exposure are needed.

The outcome of Direct Current Cardioversion (DCC) for the treatment of Atrial Fibrillation (AF) in a district general hospital in Ireland

BACKGROUND

Direct current cardioversion (DCC) is a method to control persistent AF, to facilitate a reduction in stroke risk. Although this is a frequently performed procedure, there are no available published data regarding its outcome in an Irish setting.

AIMS

To determine the short- and long-term outcome of DCC, factors predicting a successful outcome, and its safety.

METHODS

Data relating to each DCC were collected retrospectively from patient notes over a 6.3 year-period, and subsequently entered into a Microsoft Access database before subsequent statistical analysis.

RESULTS

Forty-five consecutive unselected patients were identified, in which 59 DCCs were performed. Sinus rhythm (SR) was achieved immediately after DCC in 54/59 (91%) patients. There was a significant positive correlation between patient body weight and the energy level required to achieve SR (p=0.0001). No thromboembolic complications were noted. After a mean follow-up time of 12 +/- 13.7months, 30/45 (67%) had maintained SR. After univariate analysis, a number of important factors predictive of maintenance of SR at follow-up were identified.

CONCLUSION

DCC was found to be an effective method for short- and long-term control of AF, without thromboembolic complications, and patients with a favourable long-term outcome after DCC could conceivably be predicted on the basis of a methodical history, careful examination, simple investigations and pharmacological variables.

Neonatal transportation: the effects of a national neonatal transportation programme

BACKGROUND

The transport of critically ill newborns by specialised transport teams has been shown to be associated with a significant improvement in their clinical condition on arrival at the receiving hospital.

AIM

To determine if the National Neonatal Transport Programme introduced in 2001 improved clinical condition of newborns at the end of transfer.

METHODS

A retrospective study of all 176 patients transported by the National Neonatal Transport Programme between March 2001 and March 2002.

RESULTS

Before transfer, 17% of patients were hypothermic, 2% hypoglycaemic and 11% acidotic as were 7%, 3% and 5% respectively at the end of transfer. A review of 172 neonatal transports between 1987 and 1989 revealed that 21% of patients were hypothermic, 13% hypoglycaemic and 20% acidotic at the end of transfer.

CONCLUSIONS

The National Neonatal Transport Programme has resulted in improved clinical condition of newborns at the end of transfer when compared to their condition before transfer and compared to outcomes prior to the introduction of the programme.