Organisms causing pneumonia


Pneumonia caused by Bacterium

Streptococcus pneumoniae is the most common cause of bacterial pneumonia. In a person suffering from such pneumonia shaking chills, fever and the coughing up of rust-like sputum are the abrupt signs that start to appear. In 20 to 30 per cent of such cases, infection has spread in to the blood and commonly 20 to 30 per cent infected people dies of Streptococcus pneumonia.

There are two vaccines that can be used to prevent the pneomococcal disease: the pneumococcal polysaccharide vaccine (PPV23; Pneumovax) and the pneumococcal conjugate vaccine (PCV7; Prevnar).

Some of the antibiotics can also be employed to treat such pneumonia. For example penicillin, macrolide antibiotics including erythromycin, azithromycin (Zithromax, Zmax), and clarithromycin (Biaxin), and amoxicillin and clavulanic acid (Augmentin, Augmentin XR).

In treating such infection penicillin was used to be the first choice. The abundant and wide spread use of broader-spectrum antibiotics has proved helpful in showing that the body develops significant resistance against the drug. However in the treatment of pneumococcal pneumonia pencillin can be still very effective but after testing with the cultured bacteria that they are sensitive to this antibiotic.

Hemophilus influenzae and Klebsiella pneumoniae are bacteria that are responsible for developing pneumonia in people who are already affected by alcoholism or chronic obstructive pulmonary disease (COPD).second and third generation cephalosporins, fluoroquinolones (levofloxacin [Levaquin], moxifloxacin-oral [Avelox], gatifloxacin-oral [Tequin], amoxicillin and clavulanic acid, and sulfamethoxazole and trimethoprim [Bactrim, Septra]).

Mycoplasma pneumoniae is bacteria that gradually builds up infection. The symptosm of such pneumonia includes muscle ache, rash, diarrhea, chills and fever.

atypical pneumonia is the term which refer to such pneumonia and is usually diagnosed in the summer and the fall months. For the treatment macrolides (erythromycin, clarithromycin, azithromycin, and fluoroquinolones) are typically prescribed.

Legionella pneumoniae is the bacterium that causes legionnaire’s disease. The bacteria are commonly discovered in air conditioners and contaminated water. If the infection is not accurately diagnosed then it proves to be a potentially fatal one. A part of overall infection is pneumonia along with high fever, chest pain, vomiting, nausea, slow heart beat and diarrhea. Legionnaire’s disease is commonly diagnosed in older smokers, older people and all those people whose immune system is not functioning properly. Fluoroquinolones is the best choie for the treatment. A special urine test is often prescribed for making the choice of specific antibiotic for specific organism.

“Atypical pneumonia” is a syndrome that is caused by mycoplasma, Legionnaire’s, and another infection, Chlamydia pneumoniae. Diffuse abnormalities are shown by the chest X-ray in this syndrome however the patients do not appear to be ill. It is very difficult to clinically distinguish such infection however they are confirmed in laboratories.

Pneumocystis carinii pneumonia is another type of pneumonia that commonly engages both lungs. It attacks those people whose immune system is damaged due to any reason, or example HIV/AIDS, chemotherapy of cancer and under goes treatment with TNF (tumor necrosis factor), such as for rheumatoid arthritis. If the pneumonia is diagnosed it can be well treated with sulfa-containing antibiotics. Steroids are at times used in addition in serious cases.

Pneumonia caused by Virus

Viral pneumonias are not commonly treated with antibiotics as they do not respond to such a treatment. These infections can be caused by a number of viruses such as:



Influenza virus (flu),

Respiratory syncytial virus (RSV), and

Parainfluenza virus (also causes croup).

Over time these pneumonias are resolved due to their encounter with the tough immune or defense system of the body. It is pertinent to make sure that after the resolve of viral pneumonia a secondary bacterial pneumonia must not develop. In case a secondary pneumonia is triggered by some bacterium then the treatment lies in the use of proper antibiotics. In certain cases antiviral therapy is adopted to fight off such condition.

Pneumonia caused by Fungus

A fungal infection can also lead to pneumonia. Coccidiomycosis, histoplasmosis, aspergillosis, cryptococcosis, and aspergillosis are the fungal infections that can result in to pneumonia. Such pneumonia is responsible for affecting a comparatively less number of people in the United States. Each of these fungus has its own treatment such as fluconazole (Diflucan), sulfonamides, penicillin and amphotericin B.


Pneumonia is an infection that can become potentially fatal if not diagnosed properly and treated immediately. The fact stands for all those human beings that are in their childhood, elder-hood, have serious medical problems such as diabetes, heart disease, COPD and a number of cancers. It is delightful to inform that the discovery of certain antibiotics has enabled us to tackle the infection and recover the patient successfully. However, pneumonia does not require hospitalization can be treated with oral antibiotics at home.

Bacteria, virus and fungus are the organisms that can lead to pneumonia – the disease of the lungs. Sputum producing cough, on inspiration sharp chest pain and fever are the vital signs of pneumonia. Doctors can discover pneumonia on hearing the abnormal sound of chest with stethoscope, and can order X-ray for confirming their diagnosis. Sputum culture can help in identifying the bacteria that causes pneumonia. The viral pneumonia can not be treated by the antibiotics as the organism is not sensitive to the treatment where bacteria and fungus pneumonia is treatable with antibiotics.