2. INTRODUCTION
THE PNEUMOCOCCUS IS AN ENCAPSULATED
GRAM POSITIVE COCCUS.
ELONGATED OR “LANCET-SHAPED”,ARRANGED
IN PAIRS (DIPLOCOCCI) AND SHORT CHAINS.
IT IS COVERED WITH POLYSACCHARIDE CAPSULE
AND THEIR CELL WALL COMPONENT OF THE
CELL IS TEICHOIC ACID AND PEPTIDOGLYCAN
LAYER.
ITS ALSO CONTAINS CRP,PHOSPHOCHOLINE AND
AMIDASE.
3. VIRULENCE
IT IS DETERMINED BY ABILITY TO COLONIZE
OROPHARNX BY SURFACE PROTEIN ADHESIONS.
SPREAD INTO NORMALLY STERILE TISSUES BY
PNEUMOLYSIN,IGA PROTEASE.
STIMULATE LOCAL INFLAMMATORY RESPONSE
BY TEICHOIC ACID,PEPTIDOGLYCAN
FRAGMENTS,AMIDASE,PNEUMOLYSIN
HYDROGEN PER OXIDE ,LEADS TO TISSUE
DAMAGE AND PHOSPHOCHOLINE ,PROTECTED
FROM OPSONISATION AND PHAGOCYTOSIS.
EVADE PHAGOCYTIC KILLING
(POLYSACCHARIDE CAPSULE)
4. DISEASE
PNENMONIA.(IN MOST OF THE CASES)
SINUSITIS AND OTITIS MEDIA.
MENINGITIS.
BACTEREMIA.
PERICARDITIS AND ENDOCARDITIS
SEPSIS.
OSTEOMYELETIS.
PERITONITIS AND BRAIN ABSCESS.
6. CAUSES
1. Cerebral palsy
2. Chronic lung disease
(COPD, bronchiectasis, cystic fibrosis)
3. Cigarette smoking
4. Difficulty swallowing (due
to stroke, dementia, Parkinson's disease,
or other neurological conditions)
5. Immune system problem ( Pneumonia
in immuno-compromised host)
6. Impaired consciousness (loss of brain
function due to dementia, stroke, or other
neurologic conditions)
7. Living in nursing facility
8. Other serious illnesses, such as heart
disease, liver cirrhosis, or diabetes
mellitus
9. Recent surgery or trauma
10. Recent cold, laryngitis, or flu
7. EDIDERMIOLOGY
MOST INFECTIONS ARE CAUSED BY ENDOGENOUS SPREAD
FROM THE COLONIZED NASOPHARYNX OR OROPHARYNX TO
DISTAL SITE(EG;LUNGS,SINUS,EARS,BLOOD,MENINGES)
COLONIZATION IS HIGHEST IN CHILDREN .
INDUVIDUALS WITH ANTECEDENT VIRAL RESPIRATORY
TRACT DISEASE OR OTHER CONDITIONS THAT INTERFERE
WITH BACTERIAL CLEARANCE FROM RESPIRATORY TRACT
ARE INCREASED RISK FOR PULMONARY DISEASE.
CHILDREN AND ELDERLY PEOPLE ARE AT GREATER RISK OF
MENINGITIS.
PEOPLE WITH HEMATOLOGIC
DISORDER(EG;MALIGNANCY,SICKLE CELL DISEASE) OR
FUNCTIONAL ASPLENIA ARE AT RISK FOR FULMINANT SEPSIS
ORGANISM IS UBIQUITOUS ,DISEASE IS MORE COMMON IN
COOL MONTHS.
PERSON-TO-PERSON SPREAD THROUGH INFECTIOUS
DROPLETS IS RARE.
9. LABORATORY DIAGNOSIS
MICROSCOPY IS HIGHLY SENSITIVE,AS IS CULTURE,
UNLESS THE PATIENT HAS BEEN TREATED WITH
ANTIBIOTICS.
ANTIGEN TEST FOR PNEUMOCOCCAL C POLYSACCHARIDE
IS SENSITIVE WITH CSF (MENINGITIS) .
NUCLEIC-ACID –BASED TESTS .
CULTURE REQUIRES USE OGF ENRICHED-NUTRIENT
MEDIA(EG;SHEEP BLOOD AGAR),ORGANISM HIGHLY
SUSCEPTIBLE TO MANY ANTIBIOTICS, SO CULTURE CAN BE
NEGATIVE IN PARTIALLY TREATED PATIENTS.
ISOLATES IDENTIFIED BY CATALASE (NEGATIVE),
SUSCEPTIBILTY TO OPTOCHIN,AND SOLUBILTY IN BILE.
10. TREATMENT
PENICILLIN IS THE DRUG OF CHOICE FOR
SUSCEPTIBLE STRAINS ,ALTHOUGH RESISTANCE IS
INCREASINGLY COMMON.
FLUOROQUINOLONE OR VANCOMYCIN COMBINED
WITH CEFTRIAXONE IS USED IN PATIENTS ALLERGIC
TO PENCILLIN OR PENCILLIN RESISTANCE STRAINS.
IMMUNIZATION WITH 7-VALENT CONJUGATED
VACCINE IS RECOMMENDED FOR CHILDRENS UNDER
2 YEARS, A 23-VALENT POLYSACCHARIDE VACCINE IS
RECOMMENDED FOR ADULTS AT RISK FOR DISEASE.
OTHER ANTIBIOTIC DRUGS USED ARE
AMOXILLIN,TETRACYCLINES,ERYTHROMYCIN,
AZITHOMYCIN,CLARITHROMYCIN.
11.
12. Prevention and
control :
60 % pneumonia is bacterial origin
Vaccination :
Pneumonococcal
vaccines
Maintaining immuno competancy
To be cautious about cold and flu’s
No self medication