Sputum analysis is a method of studying the physical, quantitative and qualitative properties of the secretion of the bronchi and lungs. It makes it possible to conduct bacteriological and cytological examination of sputum, which helps to assess the condition of the respiratory system and identify certain diseases.
In addition, this examination helps to determine the stage and nature of the pathological process in the lungs, which contributes to a more correct diagnosis. It is worth noting that the general analysis of sputum is one of the important studies in the pathology of the respiratory system, which allows not only to diagnose diseases, but also to determine their etiology.
Features of sputum collection
Sputum should be collected in the morning on an empty stomach, after brushing your teeth and rinsing your mouth with boiled water. In order for sputum to stand out better, on the eve of the study, the patient needs to drink plenty of fluids, and before collecting the secret from the respiratory tract, several deep breaths should be taken, and then a vigorous cough. Spit the pathological secret immediately into a sterile sealed vial for single use.
In cases where it is problematic to take sputum sampling (for example, with a dry cough), a special saline solution is inhaled. If a cough is provoked by this method, then before conducting sputum collection, the patient must spit excess saliva into a special container with a disinfectant solution.
Sputum analysis: norm and pathology
When evaluating a secret, the following criteria are taken into account:
1. The amount of sputum. Normally, sputum is released in the form of small spits (as a protective reaction). With pathology, its amount increases. So, with chronic bronchitis, up to 250 ml of secretion is released per day, and with bronchiectasis or, for example, with lung abscesses, its amount can reach 500 ml per day.
2. Character, color and consistency. Normally, the mucus from the respiratory tract is transparent, and if it becomes cloudy, this means that an inflammatory process is developing. There are cases when the mucus is transparent, but has a viscous consistency. This is in most cases observed in acute and some chronic respiratory diseases.
If a sputum analysis is performed and its yellow or green color is detected, then this indicates the accumulation of pus in the lungs. If sputum acquires an amber-orange color, then this indicates a pronounced allergic process in the body.
With an admixture of blood, sputum becomes rusty. It is worth noting that even with the appearance of minor streaks of blood, you must definitely consult a doctor to exclude severe lung pathologies.
3. The smell of sputum and its reaction. Normally, sputum should not have a smell, if it appears, then this indicates the breakdown of tissues and protein compounds in the respiratory system. The secretion reaction must be alkaline, but with prolonged standing of sputum in the respiratory system and with impurities of the gastric juice, it becomes acidic.
Sputum analysis also includes microscopy, bacterioscopy, followed by culture on a culture medium. In some diseases, the following can be detected:
• Kurshman spirals - indicate spasm in the airways;
• Charcot-Leiden crystals - talk about allergies, often found in bronchial asthma;
• blood cells - leukocytes are found in case of inflammation, eosinophils - in case of allergies and helminthic invasion, erythrocytes - in case of lung tissue destruction;
• epithelial cells and alveolar macrophages, which indicate lesions of the lower respiratory system;
• elastic fibers - can confirm lung cancer;
• eggs of various worms that are not normally found.
A bacterioscopic examination is performed to identify the causative agent of the disease. Normally, sputum contains only neysserii, alpha-hemolytic streptococci and diphtheroids.