Skip to main content

Streptococcus Pneumonia, Clinical Findings-Lab Diagnosis-Treatment.



pneumonia-examination
Streptococcus Pneumonia:

Morphology:
Shape:
The individual organism is lancet-shaped.
Arrangement:


Mostly in Pairs or sometimes in short chains.
Capsule:
Present
Motility:
Non-motile
Spore:
Non-Spore Forming.

Growth Characteristics:
1. Aerobic or facultative anaerobes.
2. Ferments glucose and produce lactic acid but not gas, Lactic acid limits its growth.
3. The optimum temperature for growth is 37-degree centigrade.
4. Growth is promoted by 5-10 % CO2.

Enzymes and Toxins Produced by Pneumococci.
1. IgA protease enhances an organism's ability to colonize mucosa of the upper respiratory tract.
2. It produces a toxin called pneumolysin. It binds to cholesterol in the host cell membrane and Inhibits antimicrobial properties of neutrophils and opsonic activity of serum. Hence it enhances the virulence of organism and organism becomes more infectious.

Habitat and Transmission.
Its normal habitat is upper respiratory tract and it transmits via respiratory droplets.

Pathogenesis and Clinical Findings.
It causes the following lesions or diseases.
1. Pneumococcal Pneumonia or Lobar pneumonia
It is characterized by an exudation of fibrinous oedema fluid into alveoli, followed by Red blood cells and leukocytes, many pneumococci are also present in alveoli. This causes consolidation of portions of lungs which can be seen in X-rays.

Clinical Findings:
a) Sudden onset of high fever with violent shaking chills,
b) Sharp pleural pain and friction rub.
c) Cough, at first dry or productive of thin watery sputum, later sputum becomes bloody or rusty.
d) Spontaneous recovery occurs between 5th and 10th days, associated with the development of type-specific development of antibodies.

2. Bacteremia and Its Complications.
Bacteremia means the presence of bacteria in the blood. From alveolar exudate organisms reach bloodstream via lymphatics and cause bacteremia, which has a triad of serious complications:
that is
a) Meningitis
b) Endocarditis
c) Septic arthritis.
Other complications include; Sinusitis, otitis media, pericarditis, Empyema and septicemia.
3. Meningitis:
Pneumococcus is the second common bacterial pathogen that causes meningitis in adults.
Pathogenesis.
a) It may arise as a complication of pneumonia, in which pneumococci reach the meninges by way of the bloodstream.
b) It may result from a skull fracture permitting pneumococci from the nasopharynx to enter the meninges.

Otitis Media.
It is responsible for 50 % of cases of otitis media in children.

Immunity:
Type-specific immunity to re-infection with pneumococci develops. It is due to type specific anticapsular antibodies.

Treatment.
Augmentin (amoxicillin + clavulanic acid) is a drug of choice.
alternative drugs are.
1. Erythromycin
2. Cephalothin
3. Chloramphenicol (for pneumococcal meningitis.)

Laboratory Diagnosis Of Streptococcus Pneumoniae

Comments

Popular posts from this blog

IELTS or OET - Reviews - Personal Experience - Which to Choose - IETLS vs OET

OET and IELTS both are used to assess the knowledge of English Language. The basic difference between the above two is this, IETLS is a more generalized English language assessment test, on the other hand, OET is profession specific. For example, if you are a doctor, the content of the test will be related to your occupation. Because of this, the OET is being chosen by many healthcare professional instead of IELTS. Both tests have the same sub-categories, that is listening, speaking, writing and reading. Lets us discuss the differences one by one. TEST OET IELTS OET Compared to IELTS is ………. (Author’s opinion) Speaking You will need to do two role plays. You will be given a situation and asked to counsel the patient about a disease and treatment or break the bad news. It has 3 parts, first is an introduction and general question, In the second part you will be provided with a topic to speak for 2 minutes. In the 3rd part, you will b...

MTI program Royal College of Physicians UK for International Doctors

  MTI (Mutual Training Initiative) is a program which is sponsored by the Royal College of Physicians UK (all three colleges), you can work in the UK for a period of up to two years.  It has the following requirements; 1. You should have MRCP part 1 passed (minimum requirement) 2. You must have got the required score in the IELTS or OET           a. For IELTS the required score is minimum 7.0 in all subcategories (reading, listening, writing and speaking) and an overall score of 7.5.           b. For OET the required score is grade B in all subcategories.  3. You must appear in an interview conducted by the Royal College of Physicians in your country and selected for the post OR you find a Job in the UK directly and inform Royal College of Physicians (London) that you have got the job by yourself and now you need RCP sponsorship for GMC registration.  You do not need to pass PLAB or MRCP (all parts) to get t...