upper respiratory tract infection
Introduction
Introduction to upper respiratory tract infection Upper respiratory tract infection is a general term for acute inflammation from the nasal cavity to the throat and is the most common infectious disease. These include infections of the nose, pharynx, and larynx, which are generally referred to as the upper sense. About 90% are caused by viruses, and bacterial infections are often followed by viral infections. The disease can occur in all seasons and at any age, and spreads through droplets, mist droplets, or contaminated utensils containing viruses. Often when the body's resistance is reduced, such as cold, fatigue, rain, etc., viruses or / and bacteria that have existed or are invaded by the outside, rapidly grow and multiply, leading to infection. The disease has a good prognosis and is self-limiting. It usually heals in 5-7 days. Often secondary to bronchitis, pneumonia, paranasal sinusitis, a small number of people can be complicated by acute myocarditis, nephritis, rheumatic fever and so on. basic knowledge The proportion of illness: 80% Susceptible people: no special people Mode of infection: non-infectious Complications: bronchitis pneumonia sinusitis myocarditis nephritis rheumatic fever
Cause
Cause of upper respiratory tract infection
Virus infection (45%):
About 70%-80% of upper respiratory tract infections are caused by viruses. There are mainly influenza viruses (A, B, C), parainfluenza viruses, respiratory syncytial virus, adenovirus, rhinovirus, echovirus, coxsackie virus, measles virus, rubella virus. Bacterial infection can occur directly or after viral infection, with hemolytic streptococcus being more common, followed by Haemophilus influenzae, pneumococcus and staphylococcus. Occasionally Gram-negative bacilli.
Reduced immunity (15%):
A variety of causes that reduce the local defense of the body or respiratory tract, such as cold, rain, excessive fatigue and other predisposing factors, so that the systemic or respiratory local defense function is reduced.
Pathogenesis:
When the body or respiratory tract local defense ability is reduced, the viruses and bacteria originally invading the upper respiratory tract or the outside can rapidly multiply and cause disease, especially those with weak or chronic respiratory diseases such as paranasal sinusitis and tonsillitis. More susceptible to this disease.
Prevention
Upper respiratory infection prevention
Enhancing the body's own disease resistance is the best way to prevent acute upper respiratory infections. Such as adhering to regular and appropriate physical exercise, adhering to the cold water bath, improve the body's ability to prevent disease and adapt to the cold. Do a good job in cold protection to avoid the cause of the disease. Life is regular, avoiding overwork, especially at night. Pay attention to the isolation of respiratory patients, prevent cross-infection, etc.
Respiratory infections are one of the most common diseases in children, especially in winter and spring. The main cause of upper respiratory tract infections is the virus, and a few are caused by bacteria or Mycoplasma pneumoniae. Mild disease is mainly watery nose, sneezing, cough, sore throat, fatigue, poor appetite, may have low fever, the course of disease is about 3-4 days, a few last for more than 1 week; severe cases can be accompanied by high fever, frequent cough, irritability A few can have febrile convulsions. The prognosis is generally good, but the infirm can cause complications such as otitis media, cervical lymphadenitis, and thick pharyngeal wall swelling. In rare cases, viral myocarditis can be induced. If the inflammation spreads down, it can cause bronchitis or pneumonia. Bacterial infections are often combined on the basis of viral infections.
The key to preventing upper respiratory tract infections:
(1) Actively exercise and enhance physical fitness;
(2) Do not wear too much in normal times, and increase or decrease clothes when the temperature changes;
(3) Avoid contact with patients. In the epidemic season of upper respiratory tract infection, try not to take children to public places. If necessary, wear masks or take traditional Chinese medicines such as Banlangen and Daqingye.
(4) timely treatment of diseases that are likely to induce upper respiratory tract infections, such as malnutrition, zinc deficiency, vitamin A deficiency, and rickets.
Complication
Upper respiratory tract infection complications Complications bronchitis pneumonia sinusitis myocarditis nephritis rheumatic fever
Often secondary to bronchitis, pneumonia, paranasal sinusitis, a small number of people can be complicated by acute myocarditis, nephritis, rheumatic fever and so on.
Symptom
Upper respiratory tract infection symptoms Common symptoms Sore throat, nasal congestion, sneezing, taste loss, low fever
First, the common cold (common cold)
Commonly known as "cold", also known as acute rhinitis or upper respiratory catarrh, with nasopharynx catarrhal symptoms as the main performance. Adults are mostly caused by rhinoviruses, followed by parainfluenza viruses, respiratory syncytial virus, echovirus, and Coxsackie virus. The onset is more urgent. In the early stage, there is dry throat, itchy itch or burning sensation. At the same time or several hours after the onset, there may be sneezing, nasal congestion, and clear watery nose, which will thicken after 2-3 days. May be associated with sore throat, sometimes due to eustachian tube inflammation, hearing loss, tearing, slow taste, poor breathing, hoarseness, a small amount of cough. Generally no fever and systemic symptoms, or only low fever, discomfort, mild chills and headaches. Examination revealed nasal congestion, edema, secretions, and mild congestion of the pharynx. If there is no complication, it usually recovers after 5-7d.
Second, viral pharyngitis, laryngitis and bronchitis
According to the inflammatory reaction caused by the virus on the anatomical parts of the upper and lower respiratory tract infections, the clinical manifestations are pharyngitis, laryngitis and bronchitis.
Acute viral pharyngitis is caused by rhinovirus, adenovirus, influenza virus, parainfluenza virus, enterovirus, respiratory syncytial virus and the like. The clinical features are itchy and burning sensation in the pharynx, and the pain is not persistent and does not stand out. When there is swallow pain, it is often suggested to have streptococcal infection. Cough is rare. Influenza and adenovirus infections can have fever and fatigue. Physical examination of the pharynx was marked by congestion and edema. The submandibular lymph nodes are swollen and tender. Adenovirus pharyngitis can be associated with ocular colitis.
Acute viral laryngitis is caused by rhinovirus, influenza A, parainfluenza and adenovirus. The clinical features are hoarseness, difficulty in speech, pain during coughing, often fever, pharyngitis or cough. Physical examination shows laryngeal edema, congestion, mild lymphadenopathy and tenderness of the local lymph nodes, and can be heard and wheezing.
Acute viral bronchitis is caused by respiratory syncytial virus, influenza virus, coronavirus, parainfluenza virus, rhinovirus, adenovirus and the like. The clinical manifestations are cough, no sputum or sputum mucus, accompanied by fever and fatigue. Other symptoms often include hoarseness and non-pleural subpleural pain. It can be smelled dry or wet. X-ray films showed increased and increased vascular shadows, but no lung infiltration shadows. Influenza or coronavirus Acute bronchitis often occurs in acute attacks of chronic bronchitis.
Third, herpes angina
Often caused by coxsackievirus A, manifested as obvious sore throat, fever, and the course of disease is about one week. Examination showed visible pharyngeal congestion, soft palate, sag, pharyngeal and tonsil surface with grayish white herpes and superficial ulcers, surrounded by redness. More than in summer, more common children, occasionally in adults.
Fourth, pharyngeal conjunctival fever
Mainly caused by adenovirus, Coxsackie virus, etc. Clinical manifestations of fever, sore throat, photophobia, tearing, pharyngeal and combined membranes were significantly congested. The course of disease is 4-6 days, which often occurs in summer and spreads during swimming. More common in children.
5. Bacterial pharyngeal-tocalitis
Mostly caused by hemolytic streptococcus, followed by Haemophilus influenzae, pneumococcus, staphylococcus and the like. Acute onset, obvious sore throat, chills, fever, body temperature can reach above 39 °C. Examination showed obvious hyperemia of the pharynx, tonsil enlargement, hyperemia, yellow spotted exudate on the surface, enlarged submandibular lymph nodes, tenderness, and no abnormal signs in the lungs.
Examine
Examination of upper respiratory tract infection
Leukocytes are low and early neutrophils are slightly elevated. The total number of white blood cells and neutrophils in the combined bacterial infection can be increased. According to the history, prevalence, symptoms and signs of nasopharynx inflammation, combined with peripheral blood and chest X-ray examination can make a clinical diagnosis. Bacterial culture and virus isolation, or virus serology, immunofluorescence, enzyme-linked immunosorbent assay, hemagglutination inhibition test, etc., can determine the cause of diagnosis.
1. Blood cell white blood cell count and classification;
2, chest X-ray examination to rule out lung disease;
3, differential diagnosis and attention to acute infectious diseases such as measles, poliomyelitis, encephalitis, meningitis, pneumonia, hemorrhagic fever with renal syndrome and leptospirosis and other prodromal symptoms;
4, the cause of diagnosis depends on virus isolation, bacterial culture and serological examination.
Diagnosis
Diagnosis and diagnosis of upper respiratory tract infection
diagnosis
Diagnosis can be performed based on clinical manifestations and examinations.
Differential diagnosis
1, allergic rhinitis: clinically like "cold", different from the onset of acute disease, nasal itching, frequent sneezing, clear watery nose, seizures related to environmental or temperature changes, sometimes abnormal odor can also occur, after Healed in a few minutes to 1-2h. Examination: pale nasal mucosa, edema, and smears of nasal secretions showed eosinophilia.
2, influenza: acute onset, systemic symptoms are heavier, high fever, body aches, conjunctival inflammation, but the symptoms of the nasopharynx are lighter. Smear specimens of mucosal epithelial cells in the nasal wash of the patient were stained with fluorescently labeled influenza virus immune serum and examined under a fluorescent microscope to facilitate early diagnosis, or virus isolation or serological diagnosis.
3, prodromal symptoms of acute infectious diseases: such as measles, poliomyelitis, encephalitis, etc., often have upper respiratory symptoms in the early stages of the disease, should be closely observed in the epidemic season or epidemic areas of these diseases, and carry out the necessary laboratory tests to Differences.
