Pulmonary Embolism or Bronchitis: These conditions are common causes of hemoptysis (coughing up blood), which can present with spitting up a mid amount of blood and small clots. Pulmonary embolism is a blockage of an artery in the lungs that can cause sudden and severe symptoms, while bronchitis is an inflammation of the lining of the bronchial tubes.

Pneumonia: An infection in the lungs that can cause inflammation and bleeding, leading to hemoptysis.
Tuberculosis (TB): A bacterial infection that can cause chronic cough, fever, and hemoptysis.
Lung Cancer: A malignant tumor in the lungs that can cause bleeding and hemoptysis.
Chronic Bronchitis: A type of chronic obstructive pulmonary disease (COPD) that can cause chronic cough and hemoptysis.

Pulmonary Arteriovenous Malformation (AVM): A rare condition where there is an abnormal connection between arteries and veins in the lungs, which can cause bleeding and hemoptysis. Missing this diagnosis can be life-threatening due to the risk of massive bleeding.
Goodpasture Syndrome: A rare autoimmune disease that can cause bleeding in the lungs and kidneys. It is essential to diagnose and treat this condition promptly to prevent severe complications.
Trauma: Any injury to the chest or lungs can cause bleeding and hemoptysis. It is crucial to consider trauma as a possible cause, especially if there is a history of recent injury.

Mitral Stenosis: A heart condition where the mitral valve is narrowed, which can cause increased pressure in the lungs and lead to bleeding.
Wegener's Granulomatosis: A rare autoimmune disease that can cause inflammation and bleeding in the lungs and other organs.
Bronchiectasis: A condition where the airways are damaged and widened, which can cause chronic cough and hemoptysis.
Cystic Fibrosis: A genetic disorder that can cause chronic respiratory infections and inflammation, leading to hemoptysis.