Blood in sputum but normal chest CT can be seen for the following reasons: such as oral diseases, nasopharyngeal diseases, tracheobronchial diseases, gastrointestinal bleeding and other reasons.
1. Oral diseases: blood in sputum can be seen in bleeding gums and oral mucous membrane.
2. Nasopharyngeal diseases: blood sputum may appear when nosebleed flows into the oral cavity and blood vessels in the laryngopharyngeal area rupture and bleed.
3. Trachea, bronchitis, airway tumor may appear cough, sputum with blood, chest CT can be normal.
4. Gastrointestinal bleeding: Gastrointestinal bleeding caused by gastroesophageal lesions manifests as vomiting blood, which is also easily confused with bloody sputum.
There may be other reasons for blood in sputum, so you should consult a doctor in time and get the right treatment under the guidance of a specialist.