The presentation and natural history of asbestos-induced diffuse pleural thickening.

BACKGROUND: Three forms of asbestos-related benign pleural disease are recognized: discrete pleural plaques, pleural effusions and diffuse pleural fibrosis. Of these, diffuse pleural fibrosis is the most significant on account of its chronicity and associated morbidity. AIMS: The objectives of this study were to determine the latency of asbestos-induced diffuse pleural fibrosis, its presenting features and its clinical course once established. METHODS: We conducted a retrospective review of 75 patients with asbestos-induced diffuse pleural fibrosis referred for assessment at our institution from 1992 to 2007. Diffuse pleural fibrosis was considered to be present if there was obliteration of the costophrenic angle in continuity with at least 3-mm pleural thickening, in accordance with the International Labour Organization 2000 Classification. RESULTS: The median latency for development of diffuse pleural fibrosis from first asbestos exposure was 34 years. Seventy-three per cent of patients had unilateral disease at presentation and 24% of these were observed to develop contralateral disease after a median of 2 years. Unilateral pleural disease was commonest on the right. Forty per cent of patients presented with pleural effusions preceding the development of diffuse pleural thickening. The median latency for development of pleural effusions from onset of exposures was 38 years. Eighty per cent of the pleural effusions were unilateral. Once established, pleural thickening was reported to have remained stable in 91% on the ipsilateral side. CONCLUSIONS: The findings of this study may help in providing further insight into the natural history of diffuse pleural fibrosis to guide the clinician in the management of this condition.

Are clinical parameters and biomarkers predictive of severity of acute pulmonary emboli on CTPA?

BACKGROUND: Previous studies have shown that findings of computed tomography pulmonary angiography (CTPA) relate to outcome in pulmonary embolus (PE). These include clot burden as quantified using an obstruction index and markers of pressure overload such as right ventricle to left ventricle size ratio (RV/LV ratio). Little data exists correlating these findings with clinical presentation and biomarkers. AIM: To explore the link between clinical presentation and biomarkers with CTPA findings. METHODS: Retrospective case note analysis of consecutive cases presenting to a large teaching hospital. An independent radiologist reviewed CTPAs and clot burden quantified using an obstruction index. RESULTS: One hundred and seventy cases were identified and notes retrieved in 137 cases. (i) CLINICAL PRESENTATION: correlation was seen between clot burden and systolic blood pressure (BP) (r = -0.299, P = 0.0006) and heart rate (r = 0.240, P = 0.0056). Median obstruction index was significantly higher in those with a presenting BP <90 mmHg [41.25% (95% CI 30-50) vs. 15% (95% CI 12.5-25), (P = 0.0004)]. Clot burden was significantly higher in patients with temperature of >37.5 degrees C [30% (95% CI 25.0-42.5) vs. 15% (95% CI 12.5-28.3), P = 0.02)] and (ii)Biomarkers: significant correlation between clot burden and D-dimer was seen (r = 0.36, P = 0.0001). Location of thrombus was associated with significant differences in D-dimer level. A subgroup of patients had cardiac biomarkers measured (n = 24). There was a statistically significant correlation between troponin I and clot burden (r = 0.412, P = 0.048) and RV/LV ratio (r = 0.699, P = 0.0013). DISCUSSION: These findings suggest that clinical parameters and biomarkers have a role in predicting the radiological severity of PE. These data support the need for further studies of risk stratification in patients presenting with acute PE.