An 8-month-old infant was evaluated for persistent polypnea with crackles and wheezing that had occurred 4 months earlier after bronchiolitis. Clinical and radiological findings led to the diagnosis of infant neuroendocrine cell hyperplasia (NEHI), a form of paediatric interstitial lung disease with a benign prognosis. The child was discharged without specific therapy and with pulmonary follow-up. The differential diagnosis with post-infectious bronchiolitis obliterans was excluded due to the absence of air trapping and mosaic attenuation. Management of NEHI includes oxygen therapy support if necessary and clinical monitoring.