A Cochrane systematic review comparing systemic antibiotics and topical treatments for chronically discharging ears with underlying eardrum perforations, in participants of any age

Chronic suppurative otitis media (CSOM) is an infection of the middle ear with pus and a persistent perforation in the eardrum. It is a common cause of preventable hearing impairment, particularly in low and middle-income countries. This review compares alternative topical treatments (antibiotics or antiseptics) with systemic (e.g. oral or injected) antibiotics, to identify which is best. Nine randomised controlled trials were included (833 randomised participants; 842 analysed participants or ears); most were poorly reported and some included a range of diagnoses.

Quinolone antibiotic drops such as ciprofloxacin were better than oral or injected antibiotics at drying the ear. This was found when compared to systemic quinolone or non-quinolone antibiotics. No benefit of adding systemic treatment to topical antibiotics was detected, although evidence was limited. The effects of topical non-quinolone antibiotics (without steroids) or antiseptics were less clear when compared to systemic treatment. Less is known about longer-term outcomes (producing a dry ear in the long-term, preventing complications, healing the eardrum, and improving hearing), or about treating complicated CSOM. The evidence in these trials about safety is also weak. More research is needed to assess whether there may be fewer adverse events with topical quinolones than with alternative topical or systemic treatments.

Authors' conclusions: 

Topical quinolone antibiotics can clear aural discharge better than systemic antibiotics; topical non-quinolone antibiotic (without steroids) or antiseptic results are less clear. Evidence regarding safety was weak. Further studies should clarify topical non-quinolones and antiseptic effectiveness, assess longer-term outcomes (for resolution, healing, hearing, or complications), and include further safety assessments, particularly to clarify the risks of ototoxicity and whether there may be fewer adverse events with topical quinolones than other topical or systemic treatments.

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Background: 

Chronic suppurative otitis media (CSOM) causes ear discharge and impairs hearing.

Objectives: 

To compare systemic antibiotics and topical antiseptics or antibiotics (excluding steroids) for treating chronically discharging ears with an underlying eardrum perforation (CSOM).

Search strategy: 

The Cochrane ENT Disorders Group Specialised Register, Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library Issue 1, 2005), MEDLINE (January 1951 to March 2005), EMBASE (January 1974 to March 2005), LILACS (January 1982 to March 2005), AMED (1985 to March 2005), CINAHL (January 1982 to March 2005), OLDMEDLINE (January 1958 to December 1965) PREMEDLINE, Metadatabase of registers of ongoing trials (mRCT), and article references.

Selection criteria: 

Randomised controlled trials; any systemic versus topical treatment (excluding steroids); participants with CSOM.

Data collection and analysis: 

One author assessed eligibility and quality, extracted data, entered data into RevMan; two authors provided a second assessment of titles and abstracts, and inputted where there was ambiguity. We contacted investigators for clarifications.

Main results: 

Nine trials (833 randomised participants; 842 analysed participants or ears). CSOM definitions and severity varied; some included mastoid cavity infections, other diagnoses, or complications. Methodological quality varied; generally poorly reported, follow-up short, handling of bilateral disease inconsistent. Topical quinolone antibiotics were better than systemic antibiotics at clearing discharge at 1-2 weeks: relative risks (RR) were, 3.21 (95% confidence interval (CI) 1.88 to 5.49) using systemic non-quinolone antibiotics (2 trials, N = 116), and 3.18 (1.87 to 5.43) using systemic quinolone (3 trials, N = 175); or 2.75 (1.38 to 5.46) in favour of systemic plus topical quinolone over systemic quinolone alone (2 trials, N = 90). No statistically significant benefit was seen at 2-4 weeks for topical non-quinolone antibiotic (without steroids) or topical antiseptic over systemic antibiotics (mostly non-quinolones), but numbers were small: one trial tested topical non-quinolones (N = 31); two tested antiseptics (N = 152). No benefit of adding systemic to topical treatment at 1-2 weeks was detected either, although evidence was limited (three trials, N = 204). Evidence regarding safety was generally weak. Adverse events reported were generally mild, although hearing worsened by ototoxicity (damaging auditory hair cells) was seen with chloramphenicol drops (non-quinolone antibiotic).