A 7-year-old girl with hematuria and clinical suspicion of Alport syndrome (AS) presented with dyspnea and nocturnal cough, initially diagnosed and treated as asthma. Despite inhaled corticosteroid therapy, her symptoms persisted, and spirometry indicated obstructive lung function without bronchodilator response. Chest CT revealed diffuse thickening of the esophageal wall, tracheal compression, with involvement of the gastric cardia, suggestive of diffuse leiomyomatosis. Subsequent genetic reanalysis confirmed the presence of a contiguous deletion of COL4A5 and COL4A6 genes, solidifying the diagnosis of AS. Diffuse leiomyomatosis, a rare benign neoplasm associated with AS, typically manifests as dysphagia, but in this case, it presented initially with asthma-like symptoms. This case emphasizes the importance of imaging when asthma treatment fails, particularly in patients with coexisting conditions of another system.