Glucocorticoid with cyclophosphamide for paraquat-induced lung fibrosis.
BACKGROUND
Paraquat is an effective and widely used herbicide but is also a lethal poison. In many developing countries paraquat is widely available and inexpensive, making poisoning prevention difficult. However most of the people who become poisoned from paraquat have taken it as a means of suicide.Standard treatment for paraquat poisoning both prevents further absorption and reduces the load of paraquat in the blood through haemoperfusion or haemodialysis. The effectiveness of standard treatments is extremely limited.The immune system plays an important role in exacerbating paraquat-induced lung fibrosis. Immunosuppressive treatment using glucocorticoid and cyclophosphamide in combination is being developed and studied.


OBJECTIVE
To assess the effects of glucocorticoid with cyclophosphamide on mortality in patients with paraquat-induced lung fibrosis.


METHODS
To identify randomised controlled trials (RCTs) on this topic, we searched the Cochrane Injuries Group's Specialised Register (searched 1 February 2012), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2012, Issue 1), MEDLINE (Ovid SP) (1946 January Week 3 2012), EMBASE (Ovid SP) (1947 to Week 4 2012), ISI Web of Science: Science Citation Index Expanded (SCI-EXPANDED) (1970 to January 2012), ISI Web of Science: Conference Proceedings Citation Index - Science (CPCI-S) (1990 to January 2012), Chinese Biomedical Literature and Retrieval System (CBM) (1978 to April 2012), Chinese Medical Current Contents (CMCC) (1995 to April 2012), and Chinese Medical Academic Conference (CMAC) (1994 to April 2012). Searches were completed on English language databases on 1 February 2012 and on Chinese language databases on 12 April 2012.


METHODS
RCTs were included in this review. All patients were to receive standard care, plus the intervention or control. The intervention was glucocorticoid with cyclophosphamide in combination versus a control of a placebo, standard care alone or any other therapy in addition to standard care.


METHODS
The mortality risk ratio (RR) and 95% confidence interval (CI) was calculated for each study on an intention-to-treat basis. Data for all-cause mortality at final follow-up were summarised in a meta-analysis using a fixed-effect model.


RESULTS
This systematic review includes three trials with a combined total of 164 participants who had moderate to severe paraquat poisoning. Patients who received glucocorticoid with cyclophosphamide in addition to standard care had a lower risk of death at final follow-up than those receiving standard care only (RR 0.72; 95% CI 0.59 to 0.89).


CONCLUSIONS
Based on the findings of three small RCTs of moderate to severely poisoned patients, glucocorticoid with cyclophosphamide in addition to standard care may be a beneficial treatment for patients with paraquat-induced lung fibrosis. To enable further study of the effects of glucocorticoid with cyclophosphamide for patients with moderate to severe paraquat poisoning, hospitals may provide this treatment as part of an RCT with allocation concealment.
Department of Neurosurgery,West China Hospital, Sichuan University, Chengdu, China. lirang58@hotmail.com.
Luying Ryan
LR
Li
Emma
E
Sydenham
Bhuwan
B
Chaudhary
Chao
C
You
D003520:Cyclophosphamide / Q000627:therapeutic use*; D004359:Drug Therapy, Combination / Q000379:methods; D005938:Glucocorticoids / Q000627:therapeutic use*; D006540:Herbicides / Q000506:poisoning*; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D010269:Paraquat / Q000506:poisoning*; D011041:Poisoning / Q000401:mortality; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000188:drug therapy* / Q000276:immunology; D016032:Randomized Controlled Trials as Topic
D005938:Glucocorticoids; D006540:Herbicides; D007166:Immunosuppressive Agents; D003520:Cyclophosphamide; D010269:Paraquat