A 48-year-old woman presented to the ED with a nonproductive cough, shortness of breath, and stridor. She was otherwise healthy and had never used tobacco. The patient was mildly tachycardic but otherwise hemodynamically stable, afebrile, and saturating well on room air. She did not display any signs of increased work of breathing at rest. Although auscultation of her thorax indicated good air entry bilaterally without any adventitious sounds, stridor was elicited with forced expiration.

A 74-year-old man presented to our department with progressive dyspnea on exertion over the last year. The patient did not report any other symptoms. He had previously smoked with a 60 pack-year history. He worked in an office and did not report any environmental, occupational, or domestic exposures. His history included asymptomatic Waldenström's macroglobulinemia that was diagnosed 18 months before respiratory symptoms. He was not receiving any treatment and was monitored regularly by the hematology department.

A 20-year-old patient with cystic fibrosis (CF) complicated by pansinusitis, pancreatic insufficiency, and diabetes presented to the local ED after an episode of large-volume hemoptysis at home. At baseline, she had advanced lung disease (FEV1, 0.97 L; 31% predicted) and upper lobe-predominant fibrocavitary changes. She was intermittently followed at a regional lung transplant center. She was previously evaluated for transplant but was not listed at the time of this presentation because of nontuberculous mycobacteria infection. She had never used tobacco, without reports of recreational inhaled drug use. Her mother had CF, and one of her brothers died in 2018 at age 24 of respiratory failure resulting from the disease.

Irritant-induced asthma (IIA) may develop after acute inhalational exposure in individuals without preexisting asthma. The effect of bronchial thermoplasty to treat intractable, worsening IIA has not yet been described. We evaluated a previously healthy 52-year-old man after inhalation of an unknown white powder. His pulmonary function and symptoms/quality of life worsened over 4 years, despite maximal guidelines-based asthma therapy. We acquired 129Xe MRI and pulmonary function test measurements on three occasions including before and after bronchial thermoplasty treatment. Seven months after bronchial thermoplasty, improved MRI ventilation and oscillometry small airway resistance were observed. Spirometry and asthma control did not improve until 19 months after bronchial thermoplasty, 5.5 years postexposure. Together, oscillometry measurements of the small airways and 129Xe MRI provided effort-independent, sensitive, and objective measurements of response to therapy. Improved MRI and oscillometry small airway resistance measurements temporally preceded improved airflow obstruction and may be considered for complex asthma cases.