Management and prevention of spontaneous pneumothorax using pleurodesis in Hong Kong.

BACKGROUND: The practice of pleurodesis for the management and prevention of spontaneous pneumothorax (SP) is uncertain. DESIGN: A retrospective multicentre analysis of patients admitted to 12 hospitals in Hong Kong with SP in 2004 and who subsequently underwent pleurodesis for the same episode. RESULTS: Pleurodesis was performed in 394 episodes. Initial medical chemical pleurodesis was performed for 258 (65.5%) patients ('initial medical group'), while 136 (34.5%) underwent initial surgical pleurodesis ('initial surgical group'). Secondary spontaneous pneumothorax (SSP; 237 episodes, 60.2%) was the most common indication for pleurodesis; it was also performed after a first episode of primary spontaneous pneumothorax (PSP) in 22 episodes (5.6%). Tetracycline derivatives (172 episodes, 66.7%) were the most popular sclerosing agents in the initial medical group. Those in the initial medical group were older and were more likely to be males, have SSP, chronic obstructive pulmonary disease and a history of past pleurodesis (P < 0.05) compared to the initial surgical group. Compared to the tetracycline group, more patients who initially received talc slurry had the procedure performed by surgeons, had larger (≥2 cm) pneumothorax or required suction during initial drainage (P < 0.05). CONCLUSIONS: Despite the availability of international guidelines, there is considerable variation in pleurodesis for SP.

Minocycline and talc slurry pleurodesis for patients with secondary spontaneous pneumothorax.

SETTING: Few studies have evaluated the sclerosing efficacy of minocycline, and none have specifically compared its sclerosing efficacy and safety profiles with talc slurry in secondary spontaneous pneumothorax (SSP). DESIGN: A retrospective analysis was conducted in patients with SSP who underwent chemical pleurodesis from January to December 2004 with minocycline or talc slurry in 12 public hospitals of Hong Kong. RESULT: There were 121 episodes of minocycline pleurodesis and 64 episodes of talc slurry pleurodesis. Immediate procedural failure were similar in the minocycline and talc slurry groups (21.5% vs. 28.1%, P = 0.31). Presence of interstitial lung disease, ≥ 2 previous episodes of pneumothorax, requiring mechanical ventilation during pleurodesis and persistent air leak before pleurodesis were independently associated with procedural failure. Pain was experienced in respectively 44.6% and 37.5% of the minocycline and the talc slurry groups. Pain was more common in patients receiving high doses of talc (≥ 5 g; P = 0.03). Respiratory distress was found in respectively 1.7% and 1.6% of the minocycline and talc slurry groups. CONCLUSION: Minocycline and talc slurry had comparable sclerosing efficacy in SSP, with immediate success rates of >70%. Pain was the most common adverse effect and respiratory distress was uncommon. Both appeared to be effective and safe for chemical pleurodesis in SSP.

Major haemoptysis in Hong Kong: aetiologies, angiographic findings and outcomes of bronchial artery embolisation.

SETTING: Tertiary referral centres. OBJECTIVE: To provide comprehensive updates on the aetiologies, angiographic findings and outcomes of bronchial artery embolisation (BAE) for life-threatening haemoptysis in Hong Kong. DESIGN: Retrospective review of clinical records of consecutive patients presenting with life-threatening haemoptysis from 2000 to 2006. RESULTS: There were 3006 admissions due to haemoptysis involving 2260 patients during the study period; of these, 251 patients had life-threatening haemoptysis. Pulmonary tuberculosis (PTB) (active or inactive) and bronchiectasis were the main underlying causes. BAE was attempted in 167 patients. There was a high prevalence of bilateral bronchial arterial abnormalities (31.7%), presence of abnormal non-bronchial arteries (41.3%) and presence of broncho-pulmonary shunt (38.9%). BAE had a high immediate success rate of 95.7%, with a 5-year recurrence rate of 45.0%. Recurrent life-threatening haemoptysis was independently associated with past history of haemoptysis (P = 0.024), presence of broncho-pulmonary shunt (P = 0.013), and incomplete embolisation (P = 0.002). Complications were uncommon (<5%) and self-limiting. CONCLUSIONS: In Hong Kong, about one tenth of admissions due to haemoptysis were life-threatening. PTB and bronchiectasis were the major causes. Complications due to BAE were uncommon and self-limiting, with super-selective catheters.

Relationship between glutathione S-transferase gene polymorphisms and enzyme activity in Hong Kong Chinese asthmatics.

BACKGROUND: Asthma is a disease associated with oxidative stress. The glutathione S-transferases (GST) are a group of enzymes that protect cells from oxidative stress. Functional genetic polymorphisms of GST genes (GSTT1, GSTM1 and GSTP1) have previously been reported. OBJECTIVE: To investigate the association of GST gene polymorphisms and its enzyme activity with the risk of asthma in Hong Kong Chinese adults. METHODS: An age- and smoking status-matched case-control study was carried out on 315 patients with asthma and 315 healthy controls. Genotyping was carried out on genomic DNA using the PCR and/or restriction fragment length polymorphism (PCR-RFLP). Plasma GST activity was measured by fluorometric assay. RESULTS: The distribution of various genotypes or alleles of the GSTT1, GSTM1 and GSTP1 was not significantly different between patients with asthma and healthy controls. The GSTM1 null genotype was found to be protective from the development of asthma in atopic subjects (odds ratios 0.55, 95% confidence interval 0.34-0.90; P=0.017). However, there was no association between GSTT1 and GSTM1 null genotypes and enzyme activity. GSTP1 codon 105 Val variants led to reduced plasma GST activity in healthy controls. Asthma patients had elevated plasma GST activity compared with healthy controls irrespective of their genotypes (P<0.001). CONCLUSION: Our data suggest that among atopic subjects, the GSTM1 null genotype is associated with a decreased risk for asthma despite increased level of plasma GST activity in asthma, but it could not distinguish whether this increase is a potentially protective compensatory effect or a pathogenic factor.

Polymorphisms of glutathione S-transferase genes and functional activity in smokers with or without COPD.

OBJECTIVE: To determine the role of polymorphisms of genes regulating glutathione S-transferase (GST) and its plasma GST activity in the pathogenesis of chronic obstructive pulmonary disease (COPD). DESIGN: Case-control study. METHODS: One hundred and sixty-three patients with stable COPD from several community or regional hospitals were matched for age and pack-years smoked with the same number of health controls from the general population. Each participant underwent an interview-based respiratory and smoking questionnaire, lung function testing and gave a blood sample. Genotyping was carried out using a polymerase chain reaction-based method for polymorphisms of glutathione S-transferase theta 1 (GSTT1), glutathione S-transferase mu 1 (GSTM1) and glutathione S-transferase P 1 (GSTP1) genes. Plasma GST activity was measured using the spectrofluorometric method. RESULTS: There were no significant differences in the distribution of various genotypes of polymorphisms of GSTT1, GSTM1 and GSTP1 between COPD patients and healthy controls. GST activity was significantly higher in patients compared with controls, irrespective of their different genotypes, and was not different between patients with different levels of airflow obstruction. CONCLUSION: Polymorphisms of GSTT1, GSTM1 and GSTP1 genes are unlikely to be involved in the pathogenesis of COPD in Chinese in Hong Kong and Southern China.