Gender/Age: Male in his 60s
History: Recently discharged from secondary care respiratory team without a clear diagnosis; referred to cardiology for further investigations

• Daily persistent breathlessness despite previous treatments

Despite multiple evaluations by the respiratory team, the underlying cause of his breathlessness was not identified. The patient had not received a FeNO test during his secondary care assessment.

Inhaled Corticosteroid (ICS): Based on the high FeNO results, treatment with an inhaled corticosteroid was initiated.

• The patient experienced a dramatic improvement in his respiratory symptoms following the ICS treatment. The cardiology referral was canceled as the cause of his breathlessness was effectively treated.