We treated 3 patients who developed respiratory disorders due to aluminum silicate, a principal component of “Kitty litter” (cat dirt). Case 1 was a 37-year-old woman with dyspnea treated for bronchial asthma for 3 months from about September 1995. Dyspnea was exacerbated after inhalation of powder from Kitty litter. On admission, disturbance of consciousness and marked hypoxemia were noted, but the patient recovered through respiratory management. Bronchoscopy showed white sputum in each segment of the bronchi. Case 2 was a 48-year-old woman with a cough exacerbated from about November 1998. Moist rales were present in expiration on chest auscultation. Symptoms were resolved by the administration of bronchodilators and expectorants. Case 3 was a 45-year-old woman with dyspnea treated for bronchial asthma since about March 1998 without improvement. Moist rales were present in bilateral lung fields during inspiration and expiration. A diagnosis of pneumonitis was made based on chest computed tomography (CT) findings recovered by bronchodilators and expectorants. From the information obtained by inquiry about the disorder, all 3 patients were considered have problems related to Kitty litter. Silica was present in the sputum of all 3 in analysis using an X-ray microanalyzer. Kitty litter causes severe symptoms on massive inhalation and respiratory disorders by inhalation of even a small amount over a long period. Precaution are thus required for indoor use.
