Tracheal wash, BAL or radiographs - is that necessary? Working up a respiratory case
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A good history and clinical examination can be used to diagnose many cases of equine respiratory disease. Endoscopy is a valuable diagnostic aid but when is it most useful and when does it add little to our clinical assessment?
Endoscopy can be useful for the detection of mild/subclinical disease, to evaluate microbiological factors, dynamic changes and to identify uncommon/ unexpected pathology. Tracheal wash samples can be useful for bacteriology and cytology, broncho-alveolar lavage (BAL) samples are usually only used for cytology and may be particularly useful for mild/ subclinical disease.