PA-1 Bacterial infections 1

Question 1

Pathogenesis

Answer 1

Ability of a micro-organism to cause disease

Question 2

The ability of a pathogen to cause disease

Answer 2

Pathogenicity

Question 3

Virulence

Answer 3

intensity of disease/ degree of harm caused

Question 4

Bacteremia

Answer 4

Bacteria present in the blood - small number not problematic

Question 5

opportunistic

Answer 5

caused by organisms that don’t normally infect healthy hosts

Question 6

primary infection

Answer 6

initial infection within a patient

Question 7

localised infection

Answer 7

infection that remains at one body site or organ

Question 8

systemic infection

Answer 8

infection that has spread to multiple organs/sited ,or spread to the blood stream

Question 9

septicemia

Answer 9

life threating condition arising from pathogens in the blood

Question 10

sepsis

Answer 10

host response to high levels of infection in the blood

Question 11

septic shock

Answer 11

sepsis accompanied by low blood pressure

Question 12

what are the common site by bacterial infection

Answer 12

Respiratory tract
Upper Respiratory tract
(nose and throat/ Ear/ Conjunctiva)
Lower Respiratory tract
(Trachea and lungs)
Urinary Tract
Lower/ upper and Ascending/ descending
Sexually Transmitted Infections
Gastrointestinal Tract
Central Nervous System
Skin, bone and soft tissue
Blood and heart
HAI

Question 13

what are the common infected places in URT ( nose and mouth)

Answer 13

Common infections=Pharyngitis and tonsillitis
Urt - Upper respiratory tract infections – Nose and throat

70 percent are viral infections so most cant be treated successfully with antibiotics

Question 14

Streptococcus sp.

Answer 14

Gram positive cocci- There are lots of different species
Divided into groups –Identified by different microbiology tests

Question 15

what are the groups Streptococcus sp.

Answer 15

Group A Streptococcus (GAS)
- Example: Streptococcus pyogenes
- Infections: Throat, skin, invasive infections (IGAS), toxic shock syndrome, necrotizing fasciitis.

Group B Streptococcus (GBS)
- Example: Streptococcus agalactiae
- Location: Gut, urinary tract, vagina.
- Infections: Serious newborn infections (e.g., meningitis), UTIs, skin, bloodstream, pneumonia, soft-tissue, bone, and joint infections.
- Screening: Pregnant women are tested for GBS in the vagina.

Group C, F, and G Streptococci
less common - still a potential to cause infcetions found in animals

Question 16

Upper respiratory tract infections (URT): Pharyngitis and tonsillitis

Main symptoms and complications

Answer 16

Inflamed tonsils, Difficulty swallowing,
Fever, headache

Opportunistic Pathogen/ Spread by Respiratory droplets

Complications:
Tonsillar abscesses (quinsy), otitis media, sinusitis, bacteraemia.

Viral * (70%) Most common

Bacterial: Group A Streptococcus (GAS)
Streptococcus pyogenes
Usually mild treatable –’Strep throat’

Question 17

what are the less common symptoms of Bacterial: Group A Streptococcus (GAS)

Answer 17

Less common symptoms
Scarlet fever- Strep throat symptoms + a body rash which spreads. (bright red/ raised pin head rash)
Often occurs in spring - school children.

Can trigger Autoimmune effect- Rheumatic fever, glomerulonephritis (Kidney)

Invasive infection (iGAS) –
Occasionally GAS infection will breach barriers to infection and become a life threatening- Systemic infection

(necrotising fasciitis and Streptococcal toxic shock syndrome)

Question 18

Acute otitis media

Answer 18

Viral* (50%) * Most common

Bacteria
Streptococcus pneumoniae
Haemophilus influenzae

Symptoms: (ACUTE)
Rapid onset, pain in ear, hearing loss,
Dizziness (balance),
fever, vomiting, diarrhoea

Ear infections are very common in young children

Question 19

Chronic otitis media

Answer 19

Viral* (50%)
Streptococcus pneumoniae
Haemophilus influenzae

Chronic infection can cause:
Tissues surrounding the Eustachian tube swell up.
Blocks Eustachian tube.
The air in the middle ear is absorbed into the surrounding tissues.
A vacuum forms in the middle ear.
Fluid accumulates.
Leads to Glue ear/ recurrent infections

Question 20

what do children get fitted to equal out the pressure in there ear due to Chronic Otitis Media

Answer 20

grommets

Question 21

Conjunctivitis symptoms, treatment

Answer 21

Symptoms:
Redness in the white of the eye / inner eyelid
Increased amount of tears
Thick yellow discharge that crusts over
theeyelashes especially aftersleep
Green or white discharge from the eye
Burning, itchyeyes
Blurred vision
Increased sensitivity to light

treatment
topical chloramphenicol