A reticular pattern on high resolution CT (HRCT) invariably represents sign
ificant lung pathology and is the dominant feature of irreversible fibrosis
. We present two cases of nitrofurantoin-induced pulmonary toxicity in whic
h the initial HRCT showed a widespread reticular pattern and associated dis
tortion of the lung parenchyma, thought to represent established fibrosis.
Follow-up HRCT scans after withdrawal of the drug showed resolution of this
supposedly irreversible pattern.