Pneumonia is a condition of severe inflammation of the lung tissue that is responsible for delivering oxygen to the entire body. The infection may be caused by bacteria, viruses, fungi or may result from an injury due to chemical agents like acids/alkalis/etc. The inflammation occurs within the alveoli which are small air sacs that make up the lung.
Signs and symptoms
Pneumonia sets in inflammation and influx of immune cells that try to curtail the infection. Mild pneumonia is said to have occurred when there are symptoms like cough with expectoration, fever, general body pain and weakness. If it continues unattended, it will progress to moderate pneumonia that will have a combination of symptoms which are more severe but not life threatening. Moderate pneumonia will lead to reduction in the oxygen levels in the body as the alveoli are filled up with cellular and bacterial debris, reducing the exchange of oxygen and carbon dioxide in the lungs; cough with profuse yellow, sputum production, fever, shivering and chills, loss of appetite, and ample weakness especially in the elderly and children. Severe pneumonia is characterized by intense high grade fever with chills, difficulty in breathing on slightest exertion, laboured breathing, hemoptysis (blood in sputum), congestion of the chest, pain in the chest while breathing and cyanosis (bluish discoloration of skin due to lack of oxygenated haemoglobin). Severe pneumonia will also cause an increased respiratory rate as there is shallow and short breathing. There is an inwards drawing of chest visible especially in thin patients (the muscles present in between the ribs are pulled inwards).
Mild pneumonia does not produce so much discomfort in the patient. Severe pneumonia will quickly deteriorate into respiratory distress or sepsis if not treated vigorously and urgently. As the oxygen saturation is low in the circulating blood in the body, it will lead to increased pulse rate and respiratory rate in moderate and severe pneumonia and patient might need to be supplied with pure oxygen from an external source. Hospitalization is a must in moderate and severe pneumonia. Mild pneumonia might be treatable at the home if not associated with any other conditions like diabetes, high blood pressure, etc.
Variation in diagnosis
Clinically, the air entry in the lungs when checked using a stethoscope will be restricted in severe pneumonia. Tapping the chest with hands by a method called percussion also helps reveal the exact patch of lungs where there is solidification and consolidation of the normally air filled sacs. Crepitations (crackling of paper like sound) will be audible in the chest in moderate and severe pneumonia as there is still time for the lung to be consolidated. Once the lung is consolidated as in severe pneumonia, there will be no respiratory sounds heard from that area of the chest. Diagnosing any pneumonia will need investigations like blood tests and a chest x-ray but severe pneumonia will need additional sputum test, culture of blood for confirming the organism that’s causing the infection, so that the appropriate antibiotic can be initiated. A CT scan might be ordered in a few cases.
Differences and variation in treatments
Mild and moderate pneumonia can be easily cured with the use of antibiotics and anti-pyretics (medicines to control fever) alone whereas severe pneumonia will need oxygen supplementation, intravenous fluids, chest physiotherapy in addition to the above mentioned drugs.
Summary:
Mild pneumonia is caused due to a single agent and hence will have few symptoms like dry cough, fever and difficulty in breathing. Severe pneumonia might be caused due to an atypical agent and hence needs high doses of anti-biotic medications which if not given will lead to consolidated patch of lung or the entire lobe of lung. The chief difference in mild, moderate and severe pneumonia is the variation in the intensity of the symptoms. The degree of breathlessness, chest pain and fatigue worsen with severe pneumonia, requiring hospitalization for treatment.