Sinusitis in children is often accompanied by upper respiratory tract infections that are not taken seriously enough for nasal examination. According to the literature, children develop upper respiratory tract infections on average 6-8 times per year, and each episode can involve the sinus mucosa and cause sinus inflammation. However, because of the lack of typical symptoms in children, the acute phase turns into chronic inflammation. The symptoms are mainly sore throat, cough and sputum, while nasal symptoms such as nasal congestion, runny nose and open mouth breathing are not known and require repeated questioning by the doctor. In particular, patients with maxillary sinusitis with cough and wheezing are first seen in pediatrics. About 30% of patients are diagnosed after 5 years. Why can purulent maxillary sinusitis trigger a cough in children? This is because inflammatory secretions (nasal mucus) can flow down into the pharynx and trachea and bronchi, and then cause a reflex cough, coughing up the mucus, which is mistaken for “sputum” and diagnosed as a “lung infection”. If sinusitis does not heal for a long time and stimulates the upper respiratory tract, it can cause chronic inflammation, bronchitis or spasm, and promote coughing and wheezing; in turn, it affects the vascular changes in the nasal mucosa, causing nasal congestion and heavy voice, swelling and pain in the throat, which aggravates the inflammation of the sinuses. Medically known as nasopulmonary reflex syndrome. How to detect pediatric maxillary sinusitis in time? The occurrence of this disease should be considered when: 1. chronic cough, coughing phlegm; 2. frequent asthma and the effect of medication is not good; 3. frequent runny nose, aggravated by cold; 4. frequent nasal itching, nasal bleeding; 5. sore throat, tonsillar hypertrophy, dizziness and headache; 6. unexplained recurrent “cold”; 7. maxillary sinus area (cheek near the nasal side) with mild pressure pain. If the above symptoms cannot be explained by a cold or lung infection, a doctor should be consulted for further nasal examination. The patient must first be thoroughly treated for sinus inflammation, as the triggering factors are removed, most of the inflammation of the upper respiratory tract is controlled, and even if there is another attack, it is easier to treat and should be taken seriously.