A 42-year-old woman comes to the office due to several months of episodic shortness of breath and cough. The patient has a history of migraines and occasionally takes acetaminophen. She is a school teacher and does not use tobacco, alcohol, or illicit drugs. Temperature is 36.1 C (97 F), blood pressure is 110/80 mm Hg, and pulse is 84/min. Pulse oximetry shows 96% on room air. Lung examination and chest x-ray are normal. Spirometry shows that FEV1 is 71% of the predicted value. Sputum analysis shows predominant eosinophils. Exposure to which of the following is most closely associated with this patient's symptoms?

Question

A 42-year-old woman comes to the office due to several months of episodic shortness of breath and cough.  The patient has a history of migraines and occasionally takes acetaminophen.  She is a school teacher and does not use tobacco, alcohol, or illicit drugs.  Temperature is 36.1 C (97 F), blood pressure is 110/80 mm Hg, and pulse is 84/min.  Pulse oximetry shows 96% on room air.  Lung examination and chest x-ray are normal.  Spirometry shows that FEV1 is 71% of the predicted value.  Sputum analysis shows predominant eosinophils.  Exposure to which of the following is most closely associated with this patient's symptoms?

Quizplus · Accepted Answer

11ec160b_3a07_703f_9249_1d0480889ac7_MD0001_00 This patient's intermittent respiratory symptoms (eg, dyspnea, cough) in the setting of a normal chest x-ray, sputum eosinophils, and reduced FEV1 (<80% predicted) are highly suggestive of asthma. Asthma is a reversible obstructive pulmonary disease characterized by bronchial hyperresponsiveness to various triggers, such as exercise, cold air, respiratory infection, and exposure to inhaled allergens. Common aeroallergens include dust mites, cockroaches, pet dander, mold, and pollen. In sensitive individuals, allergens promote bronchospasm and airway inflammation by interacting with IgE bound to pulmonary mast cells; subsequent mast cell activation leads to the release of inflammatory mediators (eg, histamine, prostaglandins, leukotrienes) and recruitment of inflammatory cells, particularly eosinophils. Therefore, allergen avoidance is an important preventive measure for patients with asthma. (Choice A) Aspirin and other nonsteroidal anti-inflammatory drugs that inhibit cyclooxygenase can precipitate asthma attacks due to leukotriene overproduction in the airways. Acetaminophen is only a weak inhibitor of cyclooxygenase, and although some evidence suggests an increased incidence of asthma in patients with frequent acetaminophen use, a clear association has not been established. (Choice B) Celiac disease (gluten-sensitive enteropathy) is caused by antibodies to gliadin, a gluten protein found in wheat. Patients classically have signs/symptoms of malabsorption (eg, diarrhea, steatorrhea, weight loss, nutrient/vitamin deficiencies). (Choice C) Although Aspergillus molds are ubiquitous in the environment and are a common trigger of asthma symptoms, Histoplasma mold is a relatively uncommon trigger. Aspergillus molds can also cause allergic bronchopulmonary aspergillosis, a chronic allergic lung condition that typically affects patients with asthma or cystic fibrosis. (Choice E) Hypersensitivity to shellfish or other seafood usually presents with urticaria, angioedema, and/or anaphylaxis immediately after food consumption. Food is rarely an inciting factor for asthma. Most commonly, food-related asthma is the result of added preservatives, such as sulfites. (Choice F) Inhalational exposure to thermophilic actinomycetes species is classically associated with hypersensitivity pneumonitis in farmers (farmer's lung). Patients typically develop respiratory and systemic symptoms (eg, fever, headache, malaise) after exposure to moldy hay or contaminated compost. Educational objective: Intermittent respiratory symptoms in a patient with a normal chest x-ray, sputum eosinophils, and reduced FEV1 suggest asthma. Common asthma triggers include exercise, cold air, respiratory infection, and exposure to inhaled allergens (eg, dust mites, cockroaches, pet dander, mold, pollen). __________ References: What do we know about asthma triggers? A review of the literature. (http://www.ncbi.nlm.nih.gov/pubmed/23574397) Bronchial asthma: diagnosis and long-term treatment in adults. (http://www.ncbi.nlm.nih.gov/pubmed/19626179)

A 42-Year-Old Woman Comes to the Office Due to Several