Pneumonia is an infection in one or both lungs caused by bacteria, viruses, and fungi. The disease causes inflammation in the air sacs in your lungs, termed as alveoli. The alveoli swell with fluid or pus, making it irritable and difficult to breathe. 

Health care providers often distinguish pneumonia based on where the disease is contracted. These assist them to predict which organisms are commonly liable for the illness and accordingly, which medication or approach is most likely to be effective.

Let us look at some of the types or variants of pneumonia –

Types of Pneumonia

Pneumonia can be categorised according to where or how it was acquired.

1. Community-acquired pneumonia (CAP): Community-acquired pneumonia (CAP) attributes to pneumonia procured outside of a medical or institutional environment. Oxidative stress is considered part of the pathogenic mechanism for community-acquired pneumonia and is closely linked to inflammation.

2.Hospital-acquired pneumonia (HAP): This type of bacterial strain pneumonia is acquired during a hospital stay. It can be more severe than other types, as the bacteria involved may be more resistant to antibiotics.

3.Ventilator-associated pneumonia (VAP): When pneumonia gets contracted while using a ventilator, it is termed VAP.

4.Aspiration pneumonia: Aspiration pneumonia occurs when you breathe bacteria into your lungs through liquids, food, or saliva. This type of pneumonia is more likely to occur if you have a swallowing problem or if you’re too laid-back from the use of medicines, alcohol, or other sedatives.

Causes of pneumonia

Several types of infectious agents can cause pneumonia:

1. Bacterial pneumonia: The most probable cause of bacterial pneumonia is Streptococcus pneumoniae.

Other causes include:

• Viral pneumonia

• Mycoplasma pneumonia

• Legionella pneumophila

• Haemophilus influenzae

2. Viral pneumonia usually is more moderate and any person suffering from it may recover in one to three weeks without medication. Respiratory viruses are frequently the cause of pneumonia; some examples include:

1.Influenza/flu

2.Respiratory syncytial virus (RSV)

3.Rhinoviruses (common cold)

3.Fungal pneumonia: Fungi from dirt or bird droppings can cause pneumonia. This type most often causes pneumonia in people with debilitated immune systems. Examples of fungi that can cause pneumonia are Cryptococcus species and Histoplasmosis species. 

Pneumonia risk factors

A risk factor is something that enhances your odds of getting sickness or condition. It can develop symptoms of pneumonia with or without the risk factors noted below. 

However, the higher risk factors a person has, the greater are the chances of developing pneumonia. If you tend to have numerous risk factors, consult your doctor about what you can do to degrade your risk. It is essential to know that anyone can get pneumonia, but certain groups have a higher risk. These groups include:

• Infants from birth to 2 years old

• Individuals of age 65 years and older

• Individuals with weakened immune systems because of illness or use of medications, such as steroids or even certain cancer drugs

• Individuals with particular chronic medical conditions, such as cystic fibrosis, asthma, diabetes, or heart failure

• Individuals who have latterly had a respiratory infection, such as a cold or the flu

• Individuals who have been lately or are currently hospitalised, essentially if they were or are on a ventilator

• Individuals who have had a stroke, have problems swallowing or have a condition that causes immobility.

• Individuals who smoke, utilise particular types of drugs or drink extreme masses of alcohol

• Individuals who have been exhibited to lung irritants, like pollution, fumes, and certain chemicals

Certain factors can also increase your risk of pneumonia, such as:

Having a weakened immune system. This is usually a problem for people with HIV/AIDS, who are alcoholic, have had an organ transplant, or have undergone chemotherapy or long-term treatment with steroids or other immunosuppressant drugs.

• Being hospitalised or being on a ventilator

• Having a chronic condition including asthma, chronic obstructive pulmonary disease, structural lung disease and heart disease

• Smoking

• Smoking and Drugs

People who smoke have a much bigger risk of developing pneumonia. If a person stops smoking, the risk will gradually reverse to standard. Nevertheless, this might take as long as ten years. 

People are also at risk for pneumonia if they are constantly exposed to second-hand/passive smoking. For instance, kids in a household where the adults usually tend to smoke also have higher rates of pneumonia than children who live in smoke-free homes.

Alcohol and drug use can put an individual at a much higher risk of pneumonia. Similar to alcohol, drug use can boost your chance of getting pneumonia and other infectious diseases. The uncertainty of pneumonia progresses among people living in congested situations, such as students in dormitories, people residing in establishments, military personnel in barracks, and even people inhabiting nursing homes. 

oxidativen stress bezeichnet

Individuals who are hospitalised have a much higher risk of developing pneumonia than do non-hospitalised individuals. This uncertainty is even higher for people who have lately undergone significant surgery or who are on ventilators. Additional medical conditions that can develop your risk of contracting pneumonia include:

• Kidney disease

• Liver disease

• Chronic obstructive pulmonary disease (COPD)

• Sleep apnea

• Diabetes

• Poor nutrition

• Mechanical ventilation/ breathing machines 

• Heart failure

• Generally debilitated state

• Allergies or asthma

• Conditions that interfere with your gag reflex:

• Stroke

• Multiple sclerosis

• Amyotrophic lateral sclerosis (ALS)

• Head injury

• Senile dementia, Alzheimer’s disease

• Conditions that weaken your immune system:

• AIDS

• History of organ transplant

• Cancer, especially leukaemia and Hodgkin lymphoma

• Chemotherapy drugs

• Immunosuppressant drugs (including steroids)

• Children have a higher risk of developing pneumonia if they have:

• Gastroesophageal reflux disorder (GERD)

• Lung or heart defects

• A weakened immune system

• Allergies or asthma

• Nervous system defects that attack the muscles of the mouth and throat

• Pneumonia is more common among certain age groups:

• Young children

• More aged/ older adults

• Infants

• Several genetic disorders can predispose you to pneumonia, such as:

• Sickle cell disease

• Cystic fibrosis

Occupational exposure to toxic synthetic fumes or smog can weaken lung’s defenses, increasing a person’s vulnerability to pneumonia germs.