The existing inertia of clinical thinking in establishing a diagnosis, even in the presence of instrumental and valid diagnostic criteria, does not always allow for a reconsideration of the diagnosis given to the patient, especially several years ago. Existing clinical recommendations for certain nosological forms, which currently play a decisive role in diagnostics, treatment, and quality assessment of medical services, may not be fully applicable to all patients with a specifi c disease. As an illustration of the above, a clinical example of a patient diagnosed with “bronchial asthma” about 15 years ago without diagnostic criteria for this condition is provided. Three years ago, on a hospitalization described in the article, a chest computed tomography scan revealed typical signs of diff use pulmonary pneumonia. However, this did not allow for a change in the stereotypical diagnostic view and the correct diagnosis and appropriate treatment, including in a specialized pulmonology department. As a result, the disease progressed with the development of complications in the form of severe respiratory and heart failure. Only a reassessment of clinical symptoms, including inspiratory crackles, chest CT scan (diffuse opacity reduction resembling ground glass), and restrictive abnormalities in external respiration function without obstructive components, allowed for a reevaluation of the diagnosis and the prescription of pathogenetic therapy with glucocorticoids in combination with treatment for respiratory and heart failure, leading to rapid clinical improvement.