gram positve bacilli

Question 1

Bacillus anthracis (zoonosis )

Answer 1

*Anaerobic,spore-forming bacilli

Pathogenesis

• Zoonosis (Cause disease in animals but can be transferred to humans as secondary hosts eg contact of an infected animal
• Disease is a result of exposure to spores
• Result in toxin-mediated and capsule diseases

Clinical disease

• Cutaneous (black eschar = coagulative necrosis )
• Pulmonary (Due to inhalation of spore> intense inflammation >hemorrhage > septicaemia)
• Digestion (infection can occur in the upper or lower GIT)

Epidemiology
found in soil
Airborne

Treatment

• Penicillin G
• *Erythromycin

Question 2

Bacilli Cereus ( food poisoning)

Answer 2

Pathogenesis

• Toxin mediated disease
• disease IS DUE TO INGESTION OF CONTAMINATED FOOD
• Exotoxins leads to food born disease
• Onset symptoms(>6 hrs) = diarrhea and abdominal cramps
• late onset of symptoms ( 8-16 hrs) = watery diarrhea

Epidemiology
*Soil , dead matter, water vegetation

Treatment
Vancomycin
Clindamycin

Question 3

Listeria monocyte gene

Answer 3

Pathogenesis

• Invades through ingestion ( contaminated food)
• They are intracellular pathogens

Transmission
Vaginally

Metabolism

• Catalase positive
• hemolytic on blood agar

Virulence
*Endotoxin (the only gram pos bacilli which as Lipopolysaccharide

Epidemiology

• Occur everywhere
• Human fecal carriers
• Found in livestock
• Love cold salty matter

Clinical disease
*Clinically seen in immune incompetent  elders
>Sepsis
>mengitis 
>encephalocities 
>abscess  
*Bacteraemia 
Endocarditis 

*Gastroenteritis (foodborne disease)

• Neonates
• In-utero infection
• stillborn
• premature labor
• Pustular skin lesions
• acute sepsis
• neonatal meningitis

Treatment
*Ampicillin

Question 4

Corynebacterium Diptheria

pseudomembrane at phayrynx

Answer 4

Morphology

• anaerobe
• Gram pos bacilli
• Non-spore-forming
• Non-motile
• looks like Chinese letters

Transmission

• Respiratory droplets
• Catalase pos

Virulence
*Pseudomembrane forms in the pharynx which serves as a base for it to secrete its toxins

Toxins

• Exotoxins coded by bacteriophage
• blocks protein synthesis by inactivating EF2
• Provides entry into the cardiac and neural tissue

Treatment

• penicillin
• ERYTHROMYCIN

Clinical

• Sore throat and fever
• Myocarditis
• neural involvement

Question 5

Norcadia spp

Answer 5

Morphology

• gram pos bacilli
• aerobic
• nonmotile
• partially fast fast acid

Who is at risk

• IMMUNE SUPPRESSED
• PROLONGED STEROID USERS
• FOUND IN TRANSPLANT PATIENTS

Epidemiology

• Found in soil
• can be airborne

Pathogenesis
*When inhaled by someone who is immune-suppressed, it infects the lungs and causes pneumonia and similar TB symptoms
or
*When traded upon, it can enter the foot and enter through small trauma and causes cellulitis and abscess