Macrolides for diffuse panbronchiolitis
Abstract
Background
Diffuse panbronchiolitis (DPB) is a chronic airways disease predominantly affecting East Asians. Macrolides, a class of antibiotics, have been used as the main treatment for DPB, based on evidence from retrospective and non‐randomised studies.
Objectives
To assess the efficacy and safety of macrolides for DPB.
Search methods
We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, issue 1), which contains the Cochrane Acute Respiratory Infections Group's Specialised Register, MEDLINE (1966 to April 2010), EMBASE (1974 to April 2010), Chinese Biomedical Literature Database (CBM) (1978 to April 2010), China National Knowledge Infrastructure (CNKI) (1974 to April 2010), KoreaMed (1997 to April 2010) and Database of Japana Centra Revuo Medicina (1983 to April 2010).
Selection criteria
Randomised controlled trials (RCTs) or quasi‐RCTs assessing the effect of macrolides for DPB.
Data collection and analysis
Two review authors independently assessed study quality and subsequent risk of bias according to the Cochrane Collaboration's tool for assessing risk of bias. The primary outcomes were five‐year survival rate, lung function and clinical response. We used risk ratios (RR) for individual trial results in the data analysis and measured all outcomes with 95% confidence intervals (CI).
Main results
Only one RCT (19 participants) with significant methodological limitations was included in this review. It found that the computerised tomography images of all participants treated with a long‐term, low‐dose macrolide (erythromycin) improved from baseline, while the images of 71.4% of participants in the control group (with no treatment) worsened and 28.6% remained unchanged. Adverse effects were not reported.
Authors' conclusions
There is little evidence for macrolides in the treatment of DPB. We are therefore unable to make any new recommendations. It may be reasonable to use low‐dose macrolides soon after diagnosis is made and to continue this treatment for at least six months, according to current guidelines.
PICOs
Plain language summary
Macrolides for diffuse panbronchiolitis
Diffuse panbronchiolitis (DPB), characterised by progressive airflow limitation and recurrent respiratory tract infection (RTI), is a chronic airways disease which predominantly affects East Asians. The prevalence of DPB in Japan is about 11 cases per 100,000 people; the prevalence outside Japan is still unknown. Macrolides are antibiotics which are used against a wide range of disease‐causing bacteria and various infectious diseases. They have been the first choice for DPB since the 1980s, based on several observational studies which found that they could significantly improve the outcome of DPB. However, high‐quality evidence to support their use is unclear. We conducted a systematic review of key medical databases, searching for high‐quality trials on the use of macrolides in the management of DPB. We retrieved only one randomised controlled trial (RCT) involving 19 participants which was of poor methodological quality. It found that the computerised tomography images of all participants treated with long‐term, low‐dose erythromycin improved from baseline, while the images of 71.4% of participants with no treatment became worse and 28.6% remained unchanged. Adverse effects were not reported.
We conclude that the use of macrolides for DPB is based on non‐RCTs or retrospective studies and there is little evidence from RCTs. We are unable to make any new recommendations based on the findings of this review. However, while awaiting evidence from new, high‐quality, well‐designed studies, it is reasonable to use low‐dose macrolides soon after diagnosis is made and to continue for at least six months, according to current guidelines.
