Serum angiotensin converting enzyme elevation in association with artificial stone silicosis.

BACKGROUND: Silicosis is a rapidly emerging major health concern for workers in the artificial stone benchtop industry. The association between serum angiotensin converting enzyme (sACE) levels and artificial stone silicosis is unknown. METHODS: We investigated 179 male workers (median age 40 years, interquartile range (IQR) 33-48 years) from the stone benchtop industry in Victoria, Australia. All had worked in an environment where dry processing of artificial stone had occurred and were registered with the Victorian Silica-associated Disease Registry between June 2019 and August 2020. Workers had undergone protocolised assessments including respiratory function testing, high resolution CT chest and blood tests panel, including sACE. FINDINGS: Sixty workers with artificial stone silicosis were identified and they had a higher median sACE level (64.1 U/L, IQR 51.5, 87.5), compared to 119 without silicosis (35.0 U/L, IQR 25.0, 47.0). Compared to those with a normal assessment, regression modelling noted significantly higher average differences in sACE levels for workers with lymphadenopathy alone (12.1 U/L, 95% confidence interval (CI): 1.3, 22.9), simple silicosis (28.7 U/L, 95% CI: 21.3, 36.0) and complicated silicosis (36.0 U/L, 95% CI 25.2, 46.9). There was a small negative association with gas transfer, but no associations with exposure duration or spirometry. CONCLUSION: sACE levels were noted to be higher in artificial stone workers with silicosis compared to those without disease and was highest in those with complicated silicosis. Longitudinal follow up is required to evaluate sACE as a prognostic biomarker for workers with this rapidly emerging occupational lung disease.

Profile of difficult to treat asthma patients referred for systematic assessment.

AIM: We determined the proportion of asthma patients under specialist care who remain difficult-to-treat and might benefit from systematic assessment. We additionally report the characteristics and indications for referral in 90 patients who received systematic assessment for difficult asthma. METHODS: We conducted a three-month prospective audit of our hospital's general asthma clinic. We then analyzed consecutive patients over 18 months referred on for systematic assessment of difficult asthma. RESULTS: Over 3 months, 22/166 patients (13.3%) in the general asthma clinic were considered likely to benefit from systematic assessment of difficult asthma. These patients had higher inhaled steroid requirements (890 ± 604 mg), lower lung function (FEV1: 65 ± 18%), and more often received GINA step 5 treatment (22.7%). However, 7/22 (32%) of suitable patients were not referred for assessment, mainly due to patient factors. Over 18 months, 90 patients received systematic assessment for difficult asthma, on account of poor symptom control (62%), frequent exacerbations (44%), poor lung function (42%), patient factors (29%), and diagnostic uncertainty (26%). There was a high disease burden with a mean (±SD) asthma control test score and asthma quality of life questionnaire score of 14 ± 5 and 4.26 ± 1.45 respectively. 80% fulfilled criteria for severe asthma. The majority were either atopic (66.7%) or eosinophilic (54.4%); only 15.6% were neither. Patients had a median of three extra-pulmonary comorbidities, of which most were previously unrecognised. CONCLUSION: One-in-eight asthma patients already under specialist care were suitable for systematic assessment of difficult asthma, but a third of these were not referred due to patient factors. Diagnostic uncertainty and patient factors were important indications for systematic assessment. Most patients who underwent systematic assessment exhibited severe asthma phenotypes potentially responsive to targeted treatment, but also had multiple comorbidities. Our results highlight the importance of management strategies to address patient factors, severe asthma biology, and concurrent contributory conditions.

Evolving practice: X-linked agammaglobulinemia and lung transplantation.

X-linked agammaglobulinemia (XLA) is a rare primary humoral immunodeficiency syndrome characterized by agammaglobulinemia, recurrent infections and bronchiectasis. Despite the association with end-stage bronchiectasis, the literature on XLA and lung transplantation is extremely limited. We report a series of 6 XLA patients with bronchiectasis who underwent lung transplantation. Short-term outcomes were excellent however long-term outcomes were disappointing with a high incidence of pulmonary sepsis and chronic lung allograft dysfunction (CLAD).