gram negative aerobic nonsporulating nonmotitile oxidase-negative paired cocci
DESCRIPTION
Meningococcus;Diplococcus intracellularis meningitidis It causes meningococcal meningitis(cerebrospinal fever) Morphology ;TRANSCRIPT
![Page 1: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/1.jpg)
Gram NegativeAerobicNonsporulatingNonmotitileOxidase-negativePaired cocci
NEISSERIA
![Page 2: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/2.jpg)
Two important pathogens,
Neisseria meningitidisNeisseria gonorrhoeae andNeisseria lactamica(rare speceis)
![Page 3: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/3.jpg)
Neisseria meningitidis
Meningococcus;Diplococcus intracellularis meningitidis
It causes meningococcal meningitis(cerebrospinal fever)
Morphology;
![Page 4: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/4.jpg)
Do not grow on ordinary media Media enriched with blood,serum or ascitic
fluid which promote growth by neutralising inhibiting substances
No growth occurs anaerobically Optimum temp;35-36degrees Optimum ph;7.4-7.6 Growth is facilitated by 5-10% CO2 &high
humidity
Cultural characteristics
![Page 5: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/5.jpg)
On solid media colonies are Small, Translucent, Round, Convex, Bluish grey
with glistening surface and entire edgesWeak hemolysis on blood agar
![Page 6: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/6.jpg)
Commonly used media,a. Blood agarb. Chocolate agarc. Muller-Hinton starch casein hydrolysate
agar. Selective medium;Modified Theyer-
Martin(with vancomycin,colistin and nystatin)
![Page 7: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/7.jpg)
Catalase-positiveOxidase-positiveIn kovac’s method-deep purple colour
appears immediately.Indole &Hydrogen sulphide-Not Produced,Nitrates-not reduced
BIOCHEMICAL REACTIONS
![Page 8: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/8.jpg)
Sugar fermentation
![Page 9: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/9.jpg)
Based on capsular polysaccharide antigens,classified into 13 serogroups……
A,B&C-Most important.groupA-EPIDEMICSgroupB-LOCALISED OUTBREAKSgroupC-BOTHGroups 29-E,W-135 &Y:causes MENINGITIS
ANTIGENIC PROPERTIES & CLASSIFICATION
![Page 10: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/10.jpg)
Very delicate organismsHighly susceptibleSensitive to penicillin &other antibioticsBut resistant strains have emerged
RESISTANCE
![Page 11: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/11.jpg)
Two main types of meningococcal diseases, 1.cerebrospinal meningitis& 2.meningococcal septicemia.Strict human parasites inhabiting the
nasopharynxAsymptomatic infectionLocal inflammation-rhinitis&pharyngitis
PATHOGENICITY
![Page 12: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/12.jpg)
cocci from nasopharynx cribriform plate to subarachanoid space meninges suppurative lesions
surface of spinal cord,
base&cortex of the brain spinal fluid
![Page 13: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/13.jpg)
Cocci are found both free & with in leucocytes
in the spinal fluid.Fatality high in untreated cases(80%)Survivors may have blindness&deafnessChronic or reccurent meningitis
![Page 14: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/14.jpg)
MENINGOCOCCEMIAAcute fever with chillsMalaise &Prostration.Metastatic involvement of joints, ears, eyes, lungs & adrenals may
occur10%-pneumonia.
![Page 15: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/15.jpg)
Fatal condition,ShockDisseminated intravascular coagulation&
Multisystem failurePathogenic agent-ENDOTOXIN released by autolysis
Vascular endothelium is sensitive to endotoxin
FULMINANT MENINGOCOCCEMIA(Waterhouse-Friderichsen syndrome)
![Page 16: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/16.jpg)
Specimens collected, 1.spinal fluid 2.blood 3.swabs from nasopharynx.1.Examination of CSF:-collected csf is devided
into 3 parts. a)1st portion-centrifuged & gram stained
smears are prepared from deposits, supernatant-meningococcal antigens
LABORATORY DIAGNOSIS
![Page 17: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/17.jpg)
B)2nd portion-inoculated on blood or chocolate agar
imp note-morphologically similar organisms.c)3rd portion-over night incubation, subcultured on chocolate agar.2.BLOOD CULTURE3.NASOPHARYNGEAL SWAB4.PETECHIAL LESIONS5.AUTOPSY6.RETROSPECTIVE EVIDENCE7.MOLECULAR DIAGNOSIS.
![Page 18: Gram Negative Aerobic Nonsporulating Nonmotitile Oxidase-negative Paired cocci](https://reader035.vdocument.in/reader035/viewer/2022081521/5a4d1c127f8b9ab0599f73e9/html5/thumbnails/18.jpg)
SulphonamidesIv penicillinGChloramphenicolCephalosporinsEradicative therapy-Rifampicin or
ciprofloxacin
TREATMENT