Types of Atypical Pneumonia

By Cashmere Lashkari, B.Sc.Reviewed by Dr. Catherine Shaffer, Ph.D.

Pneumonia

Pneumonia is a respiratory infection, which causes the air sacs in the lungs to be filled with pus or fluid. The infection is more likely to affect those with a weakened immune system. Some forms of pneumonia may be prevented with vaccination. However, there are many different causes for pneumonia. These can be broadly classified under bacterial, viral and fungal infections.

There are 30 different microbial infections that can result in pneumonia. It is not realistic to assume that a single vaccination will render the individual immune to all possible types of pneumonia. Although getting the vaccination will reduce the chance of contracting the infection.

Types of Atypical Pneumonia

Atypical pneumonia is also referred to as walking pneumonia. This is because the symptoms of the illness are not the typical symptoms of pneumonia caused by other bacteria. Atypical pneumonia is always caused by a bacterial infection.

The severity of the symptoms of walking pneumonia are not as much as regular pneumonia. In fact, often the patient doesn’t even realise that they are suffering from pneumonia. Atypical pneumonia is primarily caused by three different forms of bacteria.

1. Mycoplasma Pneumonia

This type of atypical pneumonia is caused by the Mycoplasma pneumoniae bacteria. It is a milder form of pneumonia which affects children and adults alike. Symptoms often resemble that of the common cold or flu. This includes sneezing, coughing and low grade fever. Most people are unaware that it is pneumonia and may not even receive medication for it. The illness runs its course and disappears.

2. Chlamydophila Pneumonia

The Chlamydophila pneumoniae bacteria causes this a typical pneumonia. It primarily affects children. Since it spreads due to its contagious nature, it is also known as community acquired pneumonia. It can take nearly 21 days after exposure to the bacteria for the symptoms to become visible. Symptoms include runny nose, feeling of fatigue, low fever, sore throat, headache and a slowly worsening cough. The disease has a tendency to peak every four years in the community.

3. Legionella Pneumonia

Legionnella pneumophila bacteria is responsible for this type of a typical pneumonia. This is a respiratory infection which does not spread from contact with another infected person. It spreads through mist such as that generated by air conditioning systems in a big building. Or the mist that may be generated from hot tubs or showers at the gym. Also called Legionnaire’s disease, it can be fatal. This lethal form of pneumonia is very rare. It’s a life-threatening illness, where symptoms often show up too late or not at all. If caught in time it can be treated successfully with antibiotics.

Diagnosis of Atypical Pneumonia

Mycoplasma pneumonia doesn’t have very severe symptoms. They rival the symptoms of a common cold and are usually not taken very seriously by the patient. The patient continues walking and taking care of their normal, daily routine activities, which is why it is also referred to as Walking Pneumonia. Chlamydophila pneumonia has more pronounced symptoms and is likely to be brought to the attention of a health care professional. In case of Legionnaires’ disease, the symptoms often don’t manifest until it is too late to do anything about them.

For all types of pneumonia, a chest x-ray is a good way to diagnose the infection. The sound of the lungs may also be checked via a stethoscope. Respiratory secretions may be tested to determine the type of infection. This can aid in prescribing the correct antibiotic should the infection be bacterial in nature. Blood tests may also be performed as part of the diagnostic procedure. In some cases, urine tests may also be recommended.

Treating Atypical Pneumonia

There are no vaccines currently in existence to help prevent a typical pneumonia. Even recovering from these forms of pneumonia does not guarantee immunity from a second bout with the illness. Prevention is not always possible as the bacteria may be transmitted in many different manners to the patient. However once diagnosed, Mycoplasma pneumonia, Chlamydia pneumonia and Legionella pneumonia can all be treated using antibiotics.

A sample of phlegm or a swab of the nose or throat is usually enough to help identify the bacteria causing the infection. The correct antibiotic for the infection is then easy to prescribe. The most commonly used antibiotic medication include macrolide antibiotics, fluoroquinolones, and tetracyclines. Out of these fluoroquinolones are not usually administered to young children. The other two are suitable for both adults and children.

Besides medication, patients will be asked to increase their fluid intake and get lots of rest. Some pain medication may be used to alleviate body ache. Fever may be controlled using other medication. Should blood oxygen levels run low, oxygen therapy may be recommended. Most cases are treated at home, but if the illness becomes too severe hospitalization may take place.

References

• New York Times, Atypical pneumonia, http://www.nytimes.com/health/guides/disease/atypical-pneumonia/overview.html
• Cleveland Clinic, Atypical pneumonia, https://my.clevelandclinic.org/health/articles/atypical-pneumonia-walking-pneumonia
• Johns Hopkins Medicine, Pneumonia, http://www.hopkinsmedicine.org/healthlibrary/conditions/respiratory_disorders/pneumonia_85,P01321/
• Mayo Clinic, Walking pneumonia: what does it mean? http://www.mayoclinic.org/diseases-conditions/pneumonia/expert-answers/walking-pneumonia/faq-20058530
• CDC, Chlamydia pneumoniae infection, https://www.cdc.gov/pneumonia/atypical/cpneumoniae/about/index.html
• Medline Plus, Legionnaire’s disease, https://medlineplus.gov/legionnairesdisease.html

Further Reading

• All Pneumonia Content
• Viral vs Bacterial Pneumonia
• Pneumonia Symptoms and Risk Factors
• Pneumonia Classification
• Pneumonia Cause