Urinary Leukotriene E4 as a Biomarker in NSAID-Exacerbated Respiratory Disease (N-ERD): a Systematic Review and Meta-analysis.

PURPOSE OF REVIEW: Non-steroidal exacerbated respiratory disease (N-ERD) currently requires aspirin challenge testing for diagnosis. Urinary leukotriene E4 (uLTE4) has been extensively investigated as potential biomarker in N-ERD. We aimed to assess the usefulness of uLTE4 as a biomarker in the diagnosis of N-ERD. RECENT FINDINGS: N-ERD, formerly known as aspirin-intolerant asthma (AIA), is characterised by increased leukotriene production. uLTE4 indicates cysteinyl leukotriene production, and a potential biomarker in N-ERD. Although several studies and have examined the relationship between uLTE4 and N-ERD, the usefulness of uLTE4 as a biomarker in a clinical setting remains unclear. FINDINGS: Our literature search identified 38 unique eligible studies, 35 were included in the meta-analysis. Meta-analysis was performed (i.e. pooled standardised mean difference (SMD) with 95% confidence intervals (95% CI)) and risk of bias assessed (implementing Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy (Cochrane DTA)). Data from 3376 subjects was analysed (1354 N-ERD, 1420 ATA, and 602 HC). uLTE4 was higher in N-ERD vs ATA (n = 35, SMD 0.80; 95% CI 0.72-0.89). uLTE4 increased following aspirin challenge in N-ERD (n = 12, SMD 0.56; 95% CI 0.26-0.85) but not ATA (n = 8, SMD 0.12; CI - 0.08-0.33). This systematic review and meta-analysis showed that uLTE4 is higher in N-ERD than ATA or HC. Likewise, people with N-ERD have greater increases in uLTE4 following aspirin challenge. However, due to the varied uLTE4 measurement and result reporting practice, clinical utility of these findings is limited. Future studies should be standardised to increase clinical significance and interpretability of the results.

A systematic review of the characteristics of interventions that promote physical activity in adults with asthma.

Physical activity is promoted in the asthma population through pulmonary rehabilitation, but limited funding and facilities are available. This review aimed to examine the effectiveness of interventions that promote physical activity and identify the behaviour change techniques (BCTs) and other intervention components used. Five databases were searched, and 25 studies met the inclusion criteria. Interventions had a significant positive effect on physical activity, sedentary behaviour, quality of life and asthma symptoms. BCTs used across intervention and control groups were similar in studies that showed effects and those that did not. Future interventions should employ techniques that help to maintain behaviour change.

Food for Thought: Dietary Intervention in a Rare Cause of Severe Ventilatory Failure.

Plastic bronchitis is a rare condition characterised by endobronchial cast formation. We report the case of a 53-year-old women who deteriorated following an elective bronchoscopy procedure. She developed refractory ventilatory failure and required repeated bronchoscopy, which identified thick tenacious casts as the cause of her airway compromise. She did not respond to conventional therapies including endoscopic clearance, mucolytic therapy and nebulised tissue plasminogen activator (TPA). Total parenteral nutrition and a fat-free enteral diet were instituted while the patient was on extracorporeal membrane oxygenation (ECMO), which led to substantial improvement in her condition and demonstrated the importance of dietary strategies in this case. LEARNING POINTS: Plastic bronchitis can rarely present in adults with acute ventilatory failure and life-threatening airway obstruction.Although there are no established guidelines on management, dietary intervention (e.g., a fat-free diet) should be strongly considered as a therapeutic option.Extracorporeal membrane oxygenation (ECMO) is feasible and should be considered in plastic bronchitis with airway compromise.

Bone health and disease in cystic fibrosis.

Low bone mineral density is common in children and adults with CF. It has a multifactorial aetiology that includes direct effects of CFTR dysfunction on bone cell activity, as well as the secondary effects of CFTR dysfunction including pancreatic insufficiency (leading to malnutrition/malabsorption of fat soluble vitamins) and pulmonary infection (leading to systemic inflammation and increased bone resorption). Strategies to improve bone health in CF include optimising general CF nutritional and pulmonary care and the judicious use of bisphosphonates in selected patients. CFTR correctors/potentiators may have positive impact on bone metabolism in people with CF.

Cardiac device-associated lead infection: a diagnosis not to be missed.

A 66-year-old gentleman was admitted to hospital with a history of general malaise for 5 months. His symptoms worsened 2 weeks prior to presentation. He experienced swinging pyrexia, night sweats and shortness of breath on exertion. Initial evaluation did not reveal any source of infection. Subsequent investigation revealed infection with vegetation affecting the intra-cardiac leads of cardiac resynchronization therapy device (CRT-D). The patient was treated with prolonged intravenous antibiotics and removal of the device and indwelling leads. The patient made a full recovery and a new device was implanted.

Normoammonemic encephalopathy: solely valproate induced or multiple mechanisms?

A 77-year-old woman presented with subacute onset progressive confusion, aggression, auditory hallucinations and delusions. In the preceding months, the patient had a number of admissions with transient unilateral hemiparesis with facial droop, and had been started on valproate for presumed hemiplegic migraine. Valproate was withdrawn soon after admission and her cognitive abilities have gradually improved over 3 months of follow-up. Valproate levels taken prior to withdrawal were subtherapeutic and the patient was normoammonaemic. EEG undertaken during inpatient stay showed changes consistent with encephalopathy, and low titre N-methyl-D-aspartate (NMDA) receptor antibodies were present in this patient. The possible aetiologies of valproate-induced encephalopathy and NMDA receptor-associated encephalitis present a diagnostic dilemma. We present a putative combinatorial hypothesis to explain this patient's symptoms.