When bleeding occurs in any part of the human lower respiratory tract, including the trachea, bronchi, and lungs, the process of expulsion through the coughing action is called coughing up blood. There are many causes of lower respiratory tract bleeding, and the common clinical causes include infection, inflammation, trauma, endocrine, tumor, poisoning, metabolism, and embolism. And besides respiratory system diseases, other system diseases can also cause coughing up blood.
Clinically, the cause of coughing up blood can be initially determined based on the complicating symptoms: 1. Coughing up blood with fever is considered a possible infection or tumor. Infectious etiologies include bacteria, viruses, mycoplasma, chlamydia, parasites, etc. Common diseases include pneumonia, lung abscess, tuberculosis, epidemic hemorrhagic fever, lung cancer, etc. 2, coughing up blood with chest pain: mostly consider combined pleurisy, or it may be caused by pulmonary vascular embolism leading to pulmonary infarction or lung cancer involving the pleura, common diseases include lobar pneumonia, tuberculosis, pulmonary embolism, lung cancer, etc. 3, coughing up blood with skin and mucous membrane bleeding: certain blood diseases such as leukemia, aplastic anemia, idiopathic thrombocytopenia and hemorrhage. Idiopathic thrombocytopenic purpura, etc. can cause a reduction in platelet production and coagulation dysfunction causing bleeding. The first of these is the first of a series of tests that will be conducted in the next few years.
Therefore, it is important to go to the respiratory department of a regular hospital after coughing up blood to determine the cause, taking into account the medical history, physical examination, and laboratory tests. The most common clinical tests are chest X-ray, chest CT, lung fibrinoscopy, sputum smear, sputum culture, and blood culture, which can help identify and rule out disease.