A 35-year-old grain silo worker presents 4 hours after occupational exposure with acute fever (38.9°C), productive cough, and dyspnea. Vital signs show HR 102/min, RR 24/min, BP 128/82 mmHg, SpO2 92% on room air. Chest X-ray demonstrates bilateral diffuse alveolar infiltrates. Pulmonary function testing reveals reduced FVC and DLCO with normal bronchodilator response. He denies orthopnea. Which of the following best explains the underlying pathophysiologic mechanism?
- A)Direct toxic injury from chemical fumes
- B)Type I hypersensitivity with anaphylaxis
- C)Bacterial infection from contaminated grain
- D)Type III and IV hypersensitivity reaction to organic antigenGABARITO
- E)Chronic cumulative asbestos exposure
Explicação
Acute hypersensitivity pneumonitis from grain dust exposure involves Type III immune complex deposition and Type IV cell-mediated reactions. Presents with acute restrictive pattern, reduced DLCO, and systemic symptoms within hours of antigen exposure. Ver explicação completa e trilha adaptativa →