Lec 4 Respiratory tract inf

Question 1

upper respiratory tract infections:

Answer 1

-Rhinitis
-pharyngeal and tonsillar abscesses
-pharyngitis and tonsillitis

Question 2

Middle RTI’s:

Answer 2

-epiglottis
-Laryngitis
-bronchitis/tracheobronchitis
-chronic bronchitis

Question 3

LRTI’s

Answer 3

-Acute and chronic pneumonia
-pleural effusion
-empyema
-Lung Abscess

Question 4

Streptococcus pyogenes (GABHS):

capsule, virulent factors, diseases

G+ve Catalase -ve

Answer 4

Capsule- hyaluronic acid

Virulent factors- M protein, streptokinase

Diseases-strep throat, rheumatic fever, glomerlulonephritis,impetigo

Question 5

Streptococcus agalactiae (GBS)

Capsule, vf, diseases

G+ve catalse -ve

Answer 5

Capsule- sialic acid

Virulent factor- capsule

Diseases- Neonatal sepsis, meningitis, pyogenic infections

Question 6

Streptococcus pneumonia:

a hemolytic

G+ve catalase -ve

Answer 6

Capsule- polysaccharride

Virulent factors- Capsule, neuraminidase

diseases- pneumonia, meningitis, Otitis media, pyogenic infections

Question 7

Cell wall: proteins F,M and pilli

Answer 7

Protein M- mimicry, and evade phagocytosis

Protein F- facillitates invasion

Pilli- facilitates adherence to cells

Question 8

-Group A BH streptococci- Strep pyogenes

Structure, Biologically active products

Answer 8

-Produce streptolysin S (oxygen stable) and O (epidemiologic)

structure:
Lancfield Ag
M protein
IgG binding protein
F protein
Pilli
Capsule

Biologically active EC products:
-Streptolysin O (NOT S)
-Pyrogenic exotoxins: SPE, Scarlet fever, super antigen
-C5a peptidase
-Streptokinase

treated by penicillin

Question 8

Pathogenisis of Group A streptococcal diseases:

Answer 8

Adherence to CD46
O2 role and F+M protein

Question 9

Streptococcus pneumonia: morphology and structure

Answer 9

-gram positive diplococci, oval lancet in shape
-polysacc capsule
-choline binding protein
-a-hemolytic
-pneumolysin toxin: cytokine stimulation, cillia disription
-Neuraminidase: cleaves sialic acid

Question 10

Pathogenisis of strep pneumonia:

Answer 10

-Adherance to NP cells by choline binding protein
-Aspiration
-Chronic conditions effect
-capsule effect, C3b inhibition then toxins
-Pneumococcal surface PSP-A

OPTOCHIN SENSITIVE

Question 11

Treatment of strep pneumonia:

Answer 11

-Penicillin
-mutation happens in transpeptidases not in beta lactamases
-prevention= conjugated vaccine

Question 12

Immunity of strep pneumonia :

Answer 12

antibodies to capsule
recurring
affect extreme age groups
capsule switching