Margaret Wilsher

Prevalence of airway and parenchymal abnormalities in newly diagnosed rheumatoid arthritis

BACKGROUND Pulmonary disease is a well recognised and important extra-articular manifestation of rheumatoid arthritis (RA). The objective of this study was to determine the prevalence of airway and parenchymal abnormalities in newly diagnosed patients with RA and to correlate these with clinical measures of RA severity and laboratory tests. METHODS 60 patients with a new (symptom duration <12 months) diagnosis of RA (43 females, 42 European, mean age 54, 33 ever smoker, (17 current) underwent lung function testing and high resolution computed tomography (HRCT) scored by two independent radiologists. RESULTS Eighteen (30%) patients reported respiratory symptoms: dyspnoea (11), cough (11), and wheeze (8). Twelve (20%) patients had physiologic evidence of airflow obstruction and 24 (40%) had reduced gas transfer. The prevalence of HRCT abnormalities (in any lobe) was as follows: decreased attenuation 67%, bronchiectasis 35%, bronchial wall thickening 50%, ground glass opacification 18%, reticular changes 12%. All abnormalities were more common in the lower lobes. With the exception of reduced DLCO, there were no significant differences in the prevalence of HRCT patterns or lung function parameters between smokers and non smokers. Anti-CCP antibodies and rheumatoid factor (RF) correlated strongly with DLCO and variably with other physiologic measures but poorly with radiologic abnormalities. CONCLUSION Patients with newly diagnosed RA have a moderate prevalence of airway and parenchymal abnormalities on HRCT and lower than predicted lung function parameters which cannot entirely be explained by smoking. These data suggest that pulmonary involvement is present early in the disease course in RA.

Does CT scanning predict the likelihood of a positive transbronchial biopsy in sarcoidosis

Background: Transbronchial lung biopsy (TBB) has a variable diagnostic yield in sarcoidosis. It was hypothesised that the extent and pattern of parenchymal disease on CT scanning would predict the likelihood of a positive TBB result. Methods: Patients with sarcoidosis (n = 77) were included if they had undergone a CT scan within 6 weeks of TBB. Ethnicity, symptoms, pulmonary function and site and results of TBB and bronchoalveolar lavage (BAL) were recorded. CT scans were scored quantitatively for patterns of parenchymal disease (nodular, reticular, consolidation and ground glass) on a lobar basis. Results: 39 patients (50.6%) had a positive TBB. Symptoms, ethnicity, treatment, lung volumes and chest radiographic stage were not predictors of a positive biopsy. Female gender, reduced percentage predicted carbon monoxide transfer factor and a higher percentage of lymphocytes in the BAL fluid were associated with a positive biopsy, as were higher total lung score, reticular pattern and ground-glass opacity. The associations were more significant for the total lobar score and the lobar ground-glass score of the lobe biopsied. On multivariate analysis gender, percentage of lymphocytes in the BAL fluid and total lung score were independent predictors of a positive TBB. Conclusion: The total extent of parenchymal disease on the CT scan in addition to the pattern and lobar distribution predicts the likelihood of a positive TBB at bronchoscopy.

Medical thoracoscopy in the diagnosis of unexplained pleural effusion

Abstract Approximately 20% of pleural effusions remain without an established aetiology after evaluation. Thoracoscopy has a very high sensitivity for the diagnosis of both benign and malignant diseases and greatly increases the diagnostic yield for pleural effusion. We sought to evaluate the diagnostic yield and safety of medical thoracoscopy at this institution. The records of all patients undergoing medical thoracoscopy for the evaluation of undiagnosed pleural effusion between 1990 and 1996 were reviewed. The procedure was performed under local anaesthesia with sedation using a Stortz rigid thoracoscope. Fifty‐eight patients had thoracoscopy, most having had two (range: 1–6) non‐diagnostic pleural aspirations and biopsies of the pleura. Nineteen patients were found to have mesothelioma and nine metastatic malignancy. Three patients were considered likely to have tuberculous pleural disease, six had asbestos related benign pleural fibrosis and three post‐cardiotomy syndrome. There was one chylous effusion of uncertain aetiology, one post‐traumatic and two other benign effusions, both of which resolved without clear aetiology. On seven occasions the pleural space could not be adequately accessed, but none of these patients had prior computerized tomography (CT) or ultrasound of the pleural space. There were five false negative diagnoses of malignancy, but no false positives. The diagnostic sensitivity for pleural malignancy was 85% and specificity 100%. There were no major complications, but four patients had late tumour seeding at the thoracoscopy site. Medical thoracoscopy is a safe procedure with a high diagnostic yield. Pre‐operative evaluation of the pleural collection using ultrasound or CT increases the likelihood of successful access to the pleural space and may increase diagnostic yield.

Randomized Controlled Trial of Humidified High-Flow Nasal Oxygen for Acute Respiratory Distress in the Emergency Department: The HOT-ER Study

BACKGROUND: Humidified high-flow nasal cannula (HFNC) is a novel method of oxygen delivery with increasing use in emergency departments and intensive care settings despite little evidence showing benefit over standard oxygen delivery methods (standard O2). The aim of this study was to determine whether HFNC compared with standard O2 given to subjects in acute respiratory distress would reduce the need for noninvasive ventilation or invasive ventilation. METHODS: This was a pragmatic open randomized controlled trial in adult subjects with hypoxia and tachypnea presenting to a tertiary academic hospital emergency department. The primary outcome was the need for mechanical ventilation in the emergency department. RESULTS: We screened 1,287 patients, 322 met entry criteria and 19 were excluded from analysis. Of these, 165 randomized to HFNC and 138 to standard O2 were analyzed. Baseline characteristics were similar. In the HFNC group, 3.6% (95% CI 1.5–7.9%) versus 7.2% (95% CI 3.8–13%) in the standard O2 group required mechanical ventilation in the emergency department (P = .16), and 5.5% (95% CI 2.8–10.2%) in HFNC versus 11.6% (95% CI 7.2–18.1%) in the standard O2 group required mechanical ventilation within 24 h of admission (P = .053). There was no difference in mortality or stay. Adverse effects were infrequent; however, fewer subjects in the HFNC group had a fall in Glasgow coma score due to CO2 retention, 0% (95% CI 0–3%) versus 2.2% (95% CI 0.4–6%). One in 12 subjects did not tolerate HFNC. CONCLUSIONS: HFNC was not shown to reduce the need for mechanical ventilation in the emergency department for subjects with acute respiratory distress compared with standard O2, although it was safe and may reduce the need for escalation of oxygen therapy within the first 24 h of admission.

Use of Extracorporeal Membrane Oxygenation during Resection of Tracheal Papillomatosis

WE present two cases of the use of veno-venous extracorporeal membrane oxygenation (VV-ECMO) during resection of obstructing tracheal papillomata. Conventional anesthesia techniques may be unsafe with near obstructing papillomatous disease of the trachea. The advantage of ECMO in this circumstance is that gas exchange can be totally supported for the duration of the procedure while at the same time providing an apneic unobstructed surgical field. There are reports of the use of ECMO during surgery for tracheal obstruction and resection in neonates and children, but to our knowledge this is the first account of its use in adults.

Exhaled nitric oxide in sarcoidosis.

Background: Increased production of nitric oxide (NO) by the lower respiratory tract is viewed as a marker of airway inflammation in asthma and bronchiectasis. NO is a potentially important immune modulator, inhibiting the release of several key pro-inflammatory cytokines. As sarcoidosis is characterised by granulomatous airway inflammation, we hypothesised that exhaled NO levels might be raised in sarcoidosis and correlate with the morphological extent and functional severity of disease. Methods: Fifty two patients with sarcoidosis (29 men) of mean age 42 years underwent thin section computed tomography (CT), pulmonary function tests, and measurement of exhaled NO. Results: Exhaled NO levels (median 6.8 ppb, range 2.4–21.8) did not differ significantly from values in 44 control subjects, and were not related to the extent of individual CT abnormalities or the level of pulmonary function impairment. Conclusion: Exhaled NO levels are not increased in pulmonary sarcoidosis.

The six-minute walk test using forehead oximetry is reliable in the assessment of scleroderma lung disease.

Background and objective:  The six‐minute walk test (6MWT) is a validated field test in the assessment of interstitial lung disease but may not be so useful in scleroderma (SSc) lung disease. The aim of this study was to determine the reliability of the 6MWT in patients with SSc and correlate results with morphological and functional measures of disease severity.

Pulmonary embolism: predicting disease severity

Pulmonary embolism (PE) is the most common cause of acute pulmonary hypertension, yet it is commonly undiagnosed, with risk of death if not recognized promptly and managed accordingly. Patients typically present with hypoxemia and hypocapnia, although the presentation varies greatly, being confounded by co-mordidities such as pre-existing cardio-respiratory disease. Previous studies have demonstrated variable patient outcomes in spite of similar extent and distribution of pulmonary vascular occlusion, but the pathophysiological determinants of outcome remain unclear. Computational models enable exact control over many of the compounding factors leading to functional outcomes and therefore provide a useful tool to understand and assess these mechanisms. We review the current state of pulmonary blood flow models. We present a pilot study within 10 patients presenting with acute PE, where patient-derived vascular occlusions are imposed onto an existing model of the pulmonary circulation enabling predictions of resultant haemodynamics after embolus occlusion. Results show that mechanical obstruction alone is not sufficient to cause pulmonary arterial hypertension, even when up to 65 per cent of lung tissue is occluded. Blood flow is found to preferentially redistribute to the gravitationally non-dependent regions. The presence of an additional downstream occlusion is found to significantly increase pressures.

Prevalence and prognosis of unclassifiable interstitial lung disease

To the Editor: We read with interest the recent article by Ryerson et al. [1], describing the prevalence and characteristics of patients with unclassifiable interstitial lung disease (ILD) presenting to a specialist centre. This study is the first to target specifically this newly defined disease category, in parallel with publication of the updated American Thoracic Society/European Respiratory Society classification of the idiopathic interstitial pneumonias (IIPs) [2]. The authors identified 10% of their ILD patient population as having unclassifiable ILD following multidisciplinary discussion (MDD). The major reasons for diagnostic uncertainty related to either inability or unwillingness of the patient to undergo surgical lung biopsy, or inadequacy of the tissue specimen sampled. Only a minority of cases remained ambiguous after a reasonable tissue sample had been obtained. The study detailed the clinical characteristics of this hybrid group, with many of the mean baseline demographics and disease behaviours falling between the two reference groups of patients with confirmed idiopathic pulmonary fibrosis (IPF) and non-IPF diagnoses. Multivariate analysis revealed low diffusing capacity of …

Randomised controlled trial of vitamin D supplementation in sarcoidosis

Objectives The role vitamin D intake/production plays in sarcoidosis-associated hypercalcaemia is uncertain. However, authoritative reviews have recommended avoiding sunlight exposure and vitamin D supplements, which might lead to adverse skeletal outcomes from vitamin D insufficiency. We investigated the effects of vitamin D supplementation on surrogate measures of skeletal health in patients with sarcoidosis and vitamin D insufficiency. Design Randomised, placebo-controlled trial. Setting Clinical research centre. Participants 27 normocalcaemic patients with sarcoidosis and 25-hydroxyvitamin D (25OHD) <50 nmol/L. Intervention 50 000 IU weekly cholecalciferol for 4 weeks, then 50 000 IU monthly for 11 months or placebo. Primary and secondary outcome measures The primary endpoint was the change in serum calcium over 12 months, and secondary endpoints included measurements of calcitropic hormones, bone turnover markers and bone mineral density (BMD). Results The mean age of participants was 57 years and 70% were women. The mean (SD) screening 25OHD was 35 (12) and 38 (9) nmol/L in the treatment and control groups, respectively. Vitamin D supplementation increased 25OHD to 94 nmol/L after 4 weeks, 84 nmol/L at 6 months and 78 nmol/L at 12 months, while levels remained stable in the control group. 1,25-Dihydroxy vitamin D levels were significantly different between the groups at 4 weeks, but not at 6 or 12 months. There were no between-groups differences in albumin-adjusted serum calcium, 24 h urine calcium, markers of bone turnover, parathyroid hormone or BMD over the trial. One participant developed significant hypercalcaemia after 6 weeks (total cholecalciferol dose 250 000 IU). Conclusions In patients with sarcoidosis and 25OHD <50 nmol/L, vitamin D supplements did not alter average serum calcium or urine calcium, but had no benefit on surrogate markers of skeletal health and caused one case of significant hypercalcaemia. Trial registration This trial is registered at the Australian New Zealand Clinical Trials Registry (http://www.anzctr.org.au). The registration number is ACTRN12607000364471, date of registration 5/7/2007.