Pneumonia: Types, Causes, Symptoms, Diagnosis and Treatment
What is Pneumonia?
The National Heart, Lung, and blood institute (NHLB) defines pneumonia as an infection of one or both sides of the lungs that causes the air sacs (alveoli) of the lungs to fill up with fluid or pus. When the alveoli are filled with fluid or pus, it makes breathing painful and limits oxygen intake.
Pneumonia can be life-threatening, especially in young children and the elderly population.
What are the common causes?
Pneumonia can be caused by a wide range of microorganisms such as bacteria, viruses, and fungi found in the air that we breathe.
Bacteria are the most common cause of infection in both adults and children. Pneumococcal pneumonia is the most common form of bacterial pneumonia caused by the bacteria Streptococcus pneumoniae.
Pneumonia caused by other bacteria such as Legionella pneumophila, Mycoplasma pneumoniae, and Chlamydia pneumoniae is known as atypical pneumonia. They are called so because infected patients present slightly different symptoms, appear different on a chest x-ray and respond differently to antibiotics as compared to pneumococcal pneumonia.
This type of pneumonia is caused by viruses. Influenza or flu virus is the most common cause of viral infection in adults. Respiratory syncytial virus (RSV) is a common cause of pneumonia in children <1 year of age. Most viral pneumonia is mild and resolves within 3 weeks without treatment.
Some viral pneumonia is serious and may require treatment in the hospital. For example, pneumonia caused by the Novel coronavirus 19 (COVID 19). The risk of getting bacterial pneumonia increases in a person suffering from viral pneumonia.
Fungal pneumonia is caused by a certain fungus present in contaminated soil and bird droppings. It generally affects people with a weak immune system and underlying long-term health problems such as cancer or HIV/AIDS. Pneumocystis pneumonia is a form of serious fungal pneumonia.
How common is pneumonia globally and in India?
According to the World Health Organization (Source: WHO), pneumonia is the most common infectious cause of death in children worldwide. In 2017, pneumonia accounted for 15% of all deaths reported among children <5 years of age.
In India, 3.6 million cases of severe pneumonia were reported in 2010. In the same year, pneumonia killed about 0.35 million children <5 years of age in the country.
What are the different types of pneumonia?
Hospital-acquired pneumonia: One may catch the infection during their stay in the hospital. This is known as hospital-acquired pneumonia. The risks of this type of infection are high in patients with low immunity, patients on a breathing machine (ventilator) or have a tracheotomy tube to help them breathe.
Hospital-acquired bacterial pneumonia can be serious as they are sometimes resistant to antibiotics.
Community-acquired pneumonia: When a person gets infected outside a hospital, it is known as community-acquired pneumonia.
- Aspiration pneumonia is a type of community-acquired pneumonia, where food, fluid or vomit gets into the lungs while swallowing or coughing. Bacteria can build up and cause infection if the person fails to cough up the materials in the lungs.
Who are at risk of pneumonia?
The risk of suffering from pneumonia is usually higher in,
- Children less than 2 years of age
- People above 65 years of age
- Hospitalized patients, especially if on a ventilator in an intensive care unit for long durations
- In patients with chronic lung diseases such as asthma, chronic obstructive pulmonary disease (COPD) and heart diseases
- People with habit of Smoking
- Those with a weak immune system due to pre-existing conditions such as HIV/AIDS, cancer or received an organ transplant
What are its symptoms and when to seek medical care?
During a mild infection, the signs and symptoms may be similar to a cold and flu, but they are present for a longer duration. Sometimes these become serious and lead to hospitalization.
The most common signs and symptoms of pneumonia include,
- Cough with phlegm
- Fever accompanied by chills and shivering
- Difficulty in breathing with or without chest pain
- Shortness of breath
- Feeling weak, low on energy
- Nausea, vomiting or diarrhea
Elderly patients suffering from pneumonia may also experience confusion and lower than normal body temperature.
It is advised to seek immediate medical help in case of the following conditions,
- Worsening of cough
- Fever >/=102°F
- Difficulty in breathing and chest pain
Is pneumonia contagious?
Yes, pneumonia is contagious. Coughing and sneezing by an infected person can spread the germs into the air we breathe or fall on objects or surfaces.
Maintaining good hygiene can contain the spread of germs. Such practice includes,
- Washing hands regularly with soap
- Not touching the nose, mouth, and eyes
- Covering the nose and mouth while coughing and sneezing
- Using separate plates, cups, and other utensils
- Social distancing
How is pneumonia diagnosed?
Establishing pneumonia can be challenging as patients often present with the same symptoms as that of cold and flu. In general, the following steps are recommended for an accurate diagnosis.
The doctor will note down about the symptoms experienced, a recent encounter with any person suffering from pneumonia, travel history, contact with animals and pre-existing medical conditions if any.
The doctor will note down body temperature and check for abnormal breathing with a stethoscope. The doctor may also use pulse oximetry to check the oxygen level in the blood.
The doctor may recommend the following tests on suspecting pneumonia.
- Blood tests are used to confirm the type of organism causing the infection.
- Chest x-ray helps a doctor to understand the extent and location of the infection.
- Sputum test involves examining the lung sputum to help understand the cause of the infection.
In the case of high-risk patients, the doctor may recommend additional tests such as CT scan, arterial blood gas tests, pleural fluid culture or bronchoscopy.
How is pneumonia treated?
The treatment of pneumonia depends on factors of,
- Cause and severity of illness
- Age and other health conditions of the patient
The goal for the doctor will be to manage the symptoms, cure the infection and prevent complications. It is important to stick to the treatment plan as prescribed by the doctor.
- Medication will be prescribed to control the fever and discomfort. Coughing helps move the fluids in the lungs and hence medicines that completely suppress coughing are usually not recommended.
- Antibiotics are prescribed to treat bacterial pneumonia. Antibiotics do not help if the cause of pneumonia is a viral infection. In such cases, an antiviral may be prescribed. It is important to take the complete course of the antibiotics as prescribed by the doctor to prevent recurrent infection and antibiotic resistance.
- In severe cases, hospitalization will be required where the treatment may be given via intravenous injections, other breathing support systems or surgery.
Are there any home remedies for pneumonia?
The symptoms associated with pneumonia can be managed at home by following some of the home remedies.
- Staying hydrated with enough fluids. Fluids help loosen the mucus in the lungs. Water, broth soups and tea are good options. Warm beverage prepared with honey and few drops of lemon could help. Staying away from caffeine and alcohol is recommended as they cause dehydration.
- Taking enough rest as it will take a week or a month to completely recover from the symptoms. Going out of the house and doing too many household chores should be avoided. It is advised to keep the head and the chest slightly elevated than the rest of the body using pillows while sleeping
- It is advised to seek the doctor’s advice for cough medicines. Self-medication should be avoided.
- Coughing the right way; sitting and leaning slightly forward, pressing the elbow (also pillow) into the tummy, coughing into a tissue covering the mouth.
- Warm bath/showers and steamers which releases steam can help loosen the mucus in the lungs. One could also use a humidifier in the room/house. Warm compress (a wet cloth dipped in lukewarm water) on the forehead and neck for 20-30 minutes helps soothing.
- Avoiding smoking. Smoking worsens the symptoms. Passive smoking should be avoided as well.
- Breathing exercises can help enhance oxygen flow and push mucus out of the lungs.
What are the possible complications of pneumonia?
The possible complications of pneumonia may include,
- Bacteremia and septic shock: If the bacteria spread to the blood, it is known as bacteremia. Bacteremia can lead to a serious situation known as septic shock, a fatal condition of the heart, kidney failure or heart failure.
- Lung abscesses: A condition where pus pockets are formed in the lungs. This is treated with antibiotics and removal of the pus with a needle or surgery.
- Pleural effusion and emphysema: The lungs are placed inside a cavity, known as the pleural cavity. Pneumonia can cause this cavity to fill up with fluid, causing breathing difficulties. This is known as pleural effusion. If this fluid gets infected, it is known as emphysema. Emphysema can cause chest pain, fever and breathing difficulties.
- Respiratory failure: A serious condition, where the lung is unable to supply enough oxygen to the blood. This condition is treated with a ventilator or breathing machine. Severe respiratory failure requires emergency treatment.
Does pneumonia need hospitalization?
In most cases, pneumonia can be treated successfully at home by following the doctor’s advice.
Hospitalization is required in the below mentioned patient cases of
- Severe symptoms
- Presence of complications
- Those requiring oxygen therapy or IV antibiotics
How is pneumonia treated in the emergency department?
Emergency care is usually required for patients with severe respiratory failure. The treatment focuses on restoring normal lung function.
Extracorporeal Membrane Oxygenation (ECMO) is a type of surgical intervention used for such patients. ECMO is a life-supporting machine that performs the function of the lungs and/or heart. The ECMO machine works by pumping out blood from the body to an artificial lung (oxygenator) that adds oxygen and removes carbon dioxide from it. The machine then pumps back the blood in the patient’s body.
Can pneumonia be prevented?
The risk of pneumonia is highest in children < 2 years of age. The risk of pneumonia can be prevented in this population by,
- Pneumococcal conjugate vaccine (PCV) can protect from Streptococcus pneumoniae, the most common cause of severe bacterial pneumonia among children.
- Haemophilus influenzae type b (Hib) vaccines are recommended in children to offer protection against Hib, another major cause of severe bacterial pneumonia.
- Exclusive breastfeeding up to 6 months of age
- Preventing malnutrition
- Limiting exposure to indoor smoke
- Limiting overcrowding
Elderly patients are also at higher risk of pneumonia. Routine vaccination with pneumococcal and influenza vaccination is recommended in a geriatric and susceptible population. Following a nutritious diet, avoiding overcrowding, avoiding exposure to smoke and routine check-up are advised to prevent pneumonia in them.
- WebMD. https://www.webmd.com/lung/understanding-pneumonia-basics. Accessed on March 23, 2020.
- NHS. https://www.nhs.uk/conditions/pneumonia/. Accessed on March 23, 2020.
- American Lung Association. https://www.lung.org/lung-health-diseases/lung-disease-lookup/pneumonia. Accessed on March 23, 2020.
- WHO. https://www.who.int/news-room/fact-sheets/detail/pneumonia. Accessed on March 23,2020.
- Farooqui H, Jit M, Heymann DL, Zodpey S. Burden of Severe Pneumonia, Pneumococcal Pneumonia and Pneumonia Deaths in Indian States: Modelling Based Estimates. PLoS One. 2015;10(6):e0129191.