Week 13 - Spore-forming, Gram positive bacilli

Gram Positive/Variable

Aerobic/Facultative/Anaerobic

Spore former

Motile

Bacillus

Non-motile Bacillus

B. anthracis

Aerobically and are Catalase Positive

In contrast with Genus Clostridium, Bacillus forms spores ____ __and__ _______

Also known as Anthrax bacillus, is the causative agent of Anthrax both in animals and humans

Bacillus Anthrax

Glutamic Acid capsule

Anthrax Toxic

Virulence factor of Bacillus anthrax

Edema

PA+EF equals to?

Death of the hosts cells

PA+LF equals to?

Protective Antigen

(PA) stands for?

Edema Factor

(EF) stands for?

Lethal Factor

(LF) stands for?

Protective Antigen

The ____ binds the edema factor and lethal factor enabling attachment to the host cell surface

Anthrax

Most common disease of Live-stock

Woolsorters’s Disease or Ragpickers’s Disease

Bacillus anthrax is called as ____ disease

Exposure to animal or animal products

Bacillus anthrax is acquired from?

Cutaneous

Inhalation/pulmonary

Gastrointestinal

Injectional anthrax

Forms of Bacillus anthrax are in as?

Occurs in wounds are contaminated with spores acquired through skin cuts, abrasions or insect bites

Cutaneous anthrax

Starts as a small pimple or papule at the site of the inoculation 2-3 days after exposure

Cutaneous anthrax starts as ____?

Erythematous ring; ulcerates

A __ develops and a small dark area appears in the center of the ring and eventual__l__y____ and dries

Malignant Pustule

The lesions in cutaneous anthrax are known as?

Eschar

It develops to a lesion with a dark center called?

Also called as the wool-sorter’s disease; acquired through inhalation

Inhalation Anthrax

2-5 days

____ days after exposure of inhalation anthrax manifests

Mild fever

Fatigue

Malaise

The patient with inhalation anthrax may have?

2-3 days; severe phase characterized by respiratory problems followed by disorientation, coma and death

The mild form of the inhalation anthrax lasts __ days which is followed by?

Occurs through ingestion of spores

Gastrointestinal anthrax

Abdominal pain

Nausea

Anorexia

Vomiting

Bloody Diarrhea

Symptoms of gastrointestinal anthrax?

Gastrointestinal anthrax

The fatality rate of ______ is higher than cutaneous anthrax

First recognized in Scotland during an outbreak in 2009-2010

Injectional anthrax

Characterized by soft tissue infection associated with injection of drug abuse

Injectional anthrax is characterized by?

Necrotizing fasciitis

Organ Failure

Shock

Coma

Meningitis

Injectional anthrax can be associated with?

Eschar formation

Injectional anthrax is not associated with ____?

5% of patients develop meningitis; unconsciousness and death may occur 1-6 days after exposure

Complications of Injectional anthrax

Malignant pustule

Sputum

Blood

Specimen of B. anthracis

Normally sterile sites such as blood, lung tissue and CSF

B. anthracis is isolated from?

Large

Square-ended

Gram positive/variable rods

Single or in chains

Size of B. anthracis

1\.0 to 1.5 um x 3.0 to 5.0 um

Microscopic size of B. anthracis

Bamboo rods

When in chains, the cells of B. anthrax are?

Vegetative cells can appear clear zones around the cells

Gram stains of B. anthracis may appear?

Schaeffer-Fulton; vegetative cells stain red and spores stain green

Using a _____ may stain?

Agar containing penicillin

B. anthracis can be inoculated onto?

3-6 hours at 37 degrees; it has string of pearls appearance (large spherical bacilli in chains)

Incubation of B. anthracis occurs after?

Blood agar plate

Phenylethyl Alcohol Agar

Culture media of B. anthracis

Non hemolytic

Large 2-5 mm

Colonies of B. anthracis may appear?

“Medusa head” colonies

Outgrowth of long filamentous projections may have

Beaten egg white appearance

B. anthracis has a ____ appearance

Tenacious consistency, holding tightly to the agar and they stand upright when lifted with a loop

Colonies of B. anthracis may be?

Inverted Fir tree appearance

B. anthracis may appear ___ in gelatin medium

Test for identifying B. anthrax; Catalase positive, grows aerobically/anaerobically and is nonmotile

Lecithinase Test

Glucose

Lecithinase test ferments?

Mannitol, arabinose or xylose

Lecithinase test does not ferment?

Opaque zone can be seen around colonies on egg-yolk agar

Positive indication of Lecithinase

High salt concentration (7% NaCl) and has a low pH (

B. anthracis can grow in?

Common cause of food poisoning and gastrointestinal disease; opportunistic infection in a susceptible host

Bacillus Cereus (Fried rice bacillus)

Diarrheal and Emetic (Self-limiting)

Two forms of food poisoning of B. cereus

Endophthalmitis, keratitis with abcess formation

Eye infection of B. cereus

Meningitis

Septicemia

Endocarditis

Osteomyelitis

Disease implicated in B. cereus in cases of

IV drug users, Neonates, immunosuppressed and postsurgical patients

Non gastrointestinal infections of B. cereus occur more in?

Ingestion of meat or poultry, vegetable and pasta

Diarrheal form of B. cereus

8-16 hours (long incubation)

Incubation period of B. cereus in Diarrheal form

Abdominal pain and diarrhea; 25% has vomiting

Diarrheal form of B. cereus is characterized by?

24 hours

Duration of B. cereus diarrheal form in patients?

Heat labile enterotoxin

Causes Diarrheal form of B. cereus

Occurs after ingestion of contaminated food; associated with ingestion of fried rice

Emetic Form

Nausea and vomiting 1-5 hours after ingestion

Predominant symptoms of emetic form of B. cereus

1/3 of the individuals

Diarrhea is only present in ___ of affected individuals

9 hours

Average duration of Emetic form of B. cereus

Heat stable enterotoxin

Causes Emetic form of B. cereus?

mild and self-limiting

Both forms of food poisoning in B. cereus are ___ and ____

>10^5

If ______ B. cereus cells per gram of food are present and pathogen are absent, food poisoning by this organism is confirmed

Aerobically on Blood agar at 37 degree

Culture of B. cereus can grow?

B-hemolytic, frosted glass; containing spore forming, gram positive bacilli. %%MOTILE AND LECITHINASE (+)%%

Colonies of B. cereus may appear ______ on Blood agar

Also known as Hay Bacillus; most commonly encountered laboratory contaminant

Bacillus subtillis

Bacitracin antibiotic

Bacillus subtillis is the source of

Eye infection

Bacillus subtillis can cause?

Large, flat, dull with ground glass appearance; may be B-hemolytic and may exhibit pigmentations (pink, yellow, orange or brown)

Colony appearance of B. subtillis in BAP is

Anaerobic, spore forming bacilli collectively known as clostridia; Catalase Negative and Gram positive bacilli; MOTILE

Clostridium

C. perfringens

C. ramosum

C. innocuum

Clostridium are motile except for

C. perfringens

Clostridium are non-encapsulated except for

Bacteria or their toxins usually enters the body through ingestion or open wounds that have been contaminated with soil

Clinical infection of Clostridium

Tetanus

Gas Gangrene (myonecrosis)

Botulis

Food poisoning

Diseases of Clostridium

Wounds; In Vivo

In tetanus, gas gangrene, and wound botulism, spores enter through ____ and germinate____

Also known as the Gas gangrene; most common isolate clostridium in blood culture

Clostridium perfringens

Phospholipase; tissue necrosis

Enterotoxin; gastrointestinal illness

Virulence factor of Clostridium perfringens

Subterminal spores

Position of the spores in Clostridium perfringens

True

Is Clostridium perfringens Lecithinase (+) True or False

Dome-shape, grayish white with double zone of hemolysis

Appearance of C. perfringens in BAP

Beta-hemolytic

Inner zone of hemolysis of C. perfringens is

Alpha-hemolysis

Outer zone of hemolysis of C. perfringens is

Food poisoning and Gas gangrene (myonecrosis)

Clostridium perfringens can cause

Type A and Type C

Two types of food poisoning in C. perfringens

Mild and self limiting GI illness

Type A food poisoning of C. perfringens

8-30 hours; patient experiences diarrhea and cramping abdominal pain for 24 hours

Incubation of Type A food poisoning

Also known as Enteritis Necroticans; more serious

Type C food poisoning of C. perfringens

5-6 hours; acute onset of severe abdominal pain and bloody diarrhea; may be accompanied by vomiting

Incubation of Type C food poisoning

Necrotic inflammation of the small intestine that may lead to bowel perforation; necrosis of the intestinal mucosa

Type C food poisoning can be followed by ____?

Ingestion of toxin-producing strains of clostridium perfringens

Type A and Type C food poisoning can be acquired through?

Occurs when organisms contaminate wounds through trauma or surgery; C. perfringens is the most common cause releasing potent exotoxins that enables spreading

Gas Gangrene (Myonecrosis)

(Alpha-toxins)

What exotoxin causes necrosis of the tissue in Gas Gangrene

Pain and swelling in the affected area

Manifestation of Gas gangrene (myonecrosis)

Bullae (Fluid filled blisters)

Serous discharge

Discoloration

Tissue necrosis

Observation sighted in Gas gangrene