Typical and Atypical Pneumonias, Understanding Acquired Pneumonia Categories

Pneumonia is an inflammatory process that affects the alveoli and bronchioles. Pneumonia is normally associated with an acute infection, however pneumonia can also result from other issues such as chemical inhalation, radiation therapy and aspiration of gastric contents. Pneumonia unfortunately is one of the most common causes of death in the United States.

Pneumonia is categorized according to its etiology and symptoms. Bacterial pneumonias are commonly referred to as typical pneumonias and are less common but more serious. Pneumonias caused by bacteria include streptococcus and staphylococcus, pneumocystitis carinii, and H. influenza, among others. Atypical pneumonias are pneumonias that originate from mycoplasmas, chlamydiae, fungi, parasites, viruses or Legionella pneumophila. Each atypical pneumonia has several deciding factors.

Mycoplasmas is the most common cause of atypical pneumonia. It develops gradually, over a drawn out course and is rarely fatal with treatment.

Chlamydia is also a common cause of pneumonia and upper respiratory infections. It requires a long term treatment course with an aggressive course of broad spectrum antibiotics.

Chlamydia psittaci causes psittacosis which is a flu-like condition progressing into a more consolidated pneumonia and is transmitted from sheep and birds.

Legionella pneumophila is a bacterium that resides in aquatic terrains or environments. Some of these outbreaks can be caused by bacteria ridden air conditioners and humidifiers. It is rapidly growing in nature causing severe inflammation and is often complicated by other conditions such as empyema. Symptoms usually include cough, chest pain and fever and there is a substantial mortality rate.

There are categories of pneumonia such as community acquired or CAP and these include both typical and atypical pneumonias such as viral in nature, mycoplasma, streptococcal, H influenza and others. The onsets are usually abrupt, exhibit flu like symptoms, pleuritic and may begin by an upper respiratory infection.

There are hospital acquired pneumonias or HAP that include staphylococcal, pseudomonas and Klebsiella. All these acquired pneumonias are commonly exhibited diffusely on a chest x-ray, include fever and chills, cause a productive cough and patients usually present with a toxic appearance.

Pneumonia by an acquired immunocompromised condition or host such as fungal in nature, tuberculosis or pneumocystitis carinii. These immunocompromised pneumonias exhibit by fever, night sweats, substantial weight loss, cough, breathing problems and in some instances bloody sputum.

Pneumonias can be treated depending on the originating factor with almost every antibiotic known in existence, however some pneumonias are very resistant and many times different antibiotics must be tried to find the right one for effective treatment.

References for this article include:

www.aafp.org/afp/2004/0401/p1699.html
kidshealth.org/teen/infections/bacterial_viral/pneumonia.html
www.health.state.ny.us/diseases/communicable/mycoplasma/fact_sheet.htm