Clostridial diseasesAnthrax

Clostridial diseasesClostridial diseases

ClostridiumClostridium spp. spp. Gram positive rodsGram positive rodsObligate anaerobesObligate anaerobesEndospore formingEndospore forming

ClostridiumClostridium spp. spp.

EndosporesEndosporesResistant to:Resistant to:

HeatHeatDisinfectantsDisinfectants

ClostridiumClostridium spp. spp.

Soil (found on just about all Soil (found on just about all environmental surfaces)environmental surfaces)

Fecal matter of humans and Fecal matter of humans and animalsanimals

Aquatic sedimentsAquatic sediments

ClostridiumClostridium spp. (obligate spp. (obligate anaerobes)anaerobes)

Rapidly killed by highly reactive Rapidly killed by highly reactive oxygen radicalsoxygen radicalsSinglet oxygenSinglet oxygenSuperoxide free radicalsSuperoxide free radicals

The Clostridia genusThe Clostridia genusThe clostridia produce a wide variety of The clostridia produce a wide variety of

extracellular enzymes to degrade large extracellular enzymes to degrade large biological molecules in the environment biological molecules in the environment into fermentable componentsinto fermentable components

Hence, the clostridia play an important Hence, the clostridia play an important role in nature in biodegradation and the role in nature in biodegradation and the carbon cyclecarbon cycle

In anaerobic clostridial infections, these In anaerobic clostridial infections, these enzymes play a role in invasion and enzymes play a role in invasion and pathology pathology

Grown in the laboratory under anaerobic conditions

Who are the Clostridia’s?Who are the Clostridia’s?

Most of the clostridia are saprophytes but Most of the clostridia are saprophytes but a few are pathogenic for humansa few are pathogenic for humans

Those that are pathogens have primarily Those that are pathogens have primarily a saprophytic existence in nature and, in a saprophytic existence in nature and, in a sense, are opportunistic pathogensa sense, are opportunistic pathogens

Clostridium tetaniClostridium tetani and and Clostridium Clostridium botulinumbotulinum produce the most potent produce the most potent biological toxins known to affect humansbiological toxins known to affect humans

Clostridium perfringensClostridium perfringens C. perfringens C. perfringens produces a huge array of invasins produces a huge array of invasins

and exotoxins, causes wound and and exotoxins, causes wound and surgical surgical infectionsinfections that lead to that lead to gas gangrenegas gangrene, in , in addition to severe addition to severe uterineuterine infections. infections.

Clostridial hemolysins and extracellular enzymes Clostridial hemolysins and extracellular enzymes such as proteases, lipases, collagenase and such as proteases, lipases, collagenase and hyaluronidase, contribute to the invasive processhyaluronidase, contribute to the invasive process

C. perfringens C. perfringens also produces an enterotoxin and is also produces an enterotoxin and is an important cause of an important cause of food poisoningfood poisoning..

Usually Usually C. perfringensC. perfringens and and C. botulinumC. botulinum is is encountered in improperly sterilized (canned) encountered in improperly sterilized (canned) foods in which endospores have germinatedfoods in which endospores have germinated

Clostridium difficileClostridium difficile

Pseudomembranous colitisPseudomembranous colitis in humans in humans is caused by overgrowth ofis caused by overgrowth ofClostridium Clostridium difficiledifficile in the colon, usually after the in the colon, usually after the normal flora has been disturbed by normal flora has been disturbed by antimicrobial chemotherapy. antimicrobial chemotherapy.

C. difficileC. difficile produces two toxins: Toxin A is produces two toxins: Toxin A is referred to as an enterotoxin because it referred to as an enterotoxin because it causes fluid accumulation in the bowelcauses fluid accumulation in the bowel

Toxin B is an extremely lethal Toxin B is an extremely lethal (cytopathic) toxin. (cytopathic) toxin.

Clostridium tetaniClostridium tetani Clostridium tetaniClostridium tetani is the causative agent of is the causative agent of

tetanustetanus. . The organism is found in soil, especially heavily-The organism is found in soil, especially heavily-

manured soils, and in the intestinal tracts and manured soils, and in the intestinal tracts and feces of various animals. feces of various animals.

Carrier rates in humans vary from 0 to 25%, and Carrier rates in humans vary from 0 to 25%, and the organism is thought to be a transient member the organism is thought to be a transient member of the flora whose presence depends upon of the flora whose presence depends upon ingestion.ingestion.

The organism produces terminal spores within a The organism produces terminal spores within a swollen sporangium giving it a distinctive swollen sporangium giving it a distinctive drumstick appearance.drumstick appearance.

Although the bacterium has a typical Gram-Although the bacterium has a typical Gram-positive cell wall, it may stain Gram-negative or positive cell wall, it may stain Gram-negative or Gram-variable, especially in older cells. Gram-variable, especially in older cells.

Neutralization of oxygen Neutralization of oxygen radicalsradicals

Superoxide Dismutase Superoxide Dismutase (SOD)(SOD)

CatalaseCatalaseClostridium Clostridium spp. lacks these spp. lacks these

enzymesenzymes

ClostridiumClostridium spp. spp.

C. tetaniC. tetani C. botulinumC. botulinum C. perfringensC. perfringensC. difficileC. difficile

Clostridium tetani“Drumstick” appearance

Clostridial diseasesClostridial diseases

TetanusTetanusBotulismBotulismGas gangreneGas gangreneFoodborne gastroenteritisFoodborne gastroenteritisPseudomembrane colitisPseudomembrane colitis

TETANUSTETANUS

Localized infection, Localized infection, caused by a caused by a C.tetaniC.tetani toxin toxin

General muscle spasms-General muscle spasms-due to neurotoxindue to neurotoxin

Trauma (often trivial)Trauma (often trivial)Chronic skin ulcersChronic skin ulcersUmbilical cord (clay Umbilical cord (clay

matter ritual in Africa)matter ritual in Africa)Abortion (unsanitary Abortion (unsanitary

abortions)abortions)

TETANUS (TETANUS (cont.cont.))

TETANUS (TETANUS (cont.cont.))300,000/year world wide300,000/year world wide100 cases/year in the USA (24 100 cases/year in the USA (24

fatal)fatal)70% unvaccinated, or 70% unvaccinated, or incomplete vaccination regimeincomplete vaccination regime

Mostly 60 years and olderMostly 60 years and older

TETANUS (TETANUS (cont.cont.))

Spores in woundSpores in woundInfection and/or tissue Infection and/or tissue necrosisnecrosis

Low OLow O22 tension tension Spore germinationSpore germination

TETANOSPASMINTETANOSPASMIN

Blocks the muscle Blocks the muscle relaxation pathwayrelaxation pathway

Death results from spasms Death results from spasms of respiratory musclesof respiratory muscles

Released from dead Released from dead bacterial cellsbacterial cells

TETANOSPASMIN (TETANOSPASMIN (cont.cont.))

Once it attaches to Once it attaches to nerves, therapy is usually nerves, therapy is usually ineffectiveineffective

Advanced case of tetanus

Greek tetanos, to stretch

TREATMENT OF TETANUSTREATMENT OF TETANUS

Removal of necrotized Removal of necrotized (death) tissue(death) tissue

AntibioticsAntibioticsHuman Human immunoglobulinsimmunoglobulins

TETANUS VACCINETETANUS VACCINE

-S-S-

Toxin Toxoid

Active Inactive

Enzyme

TETANUS VACCINATION TETANUS VACCINATION SCHEDULE (CDC)SCHEDULE (CDC)

DTaP vaccine (Diptheria, DTaP vaccine (Diptheria, Tetanus & acellular Tetanus & acellular pertussis)pertussis)

2, 4, 6 and 12-18 months2, 4, 6 and 12-18 months4-6 years4-6 years

FOODBORNE BOTULISMFOODBORNE BOTULISM

A A non-infectiousnon-infectious food food poisoning poisoning

C. botulinum C. botulinum neurotoxin neurotoxin in contaminated foodin contaminated food

34 cases in 1994 (USA)34 cases in 1994 (USA)

FOODBORNE BOTULISM FOODBORNE BOTULISM ((cont.cont.))

BOTULIN TOXINBOTULIN TOXINMost potent of all natural Most potent of all natural

toxinstoxins Approx. 0.001 mg human Approx. 0.001 mg human lethal doselethal dose

Causes flaccid paralysisCauses flaccid paralysisDeath follows cardiac Death follows cardiac

failurefailure

Definitive DiagnosisDefinitive Diagnosis

only establish with toxin only establish with toxin identification:identification:

Isolation of toxigenic cultures and Isolation of toxigenic cultures and identification of the involved type C identification of the involved type C or D toxin with the aid of serum or D toxin with the aid of serum neutralization in mice or guinea-pigs. neutralization in mice or guinea-pigs.

Toxin detection in clinical samples Toxin detection in clinical samples collected for laboratory analysis collected for laboratory analysis (intestinal contents)(intestinal contents)

Type of tests to ID botulismType of tests to ID botulism

tests may include a brain scan, spinal fluid tests may include a brain scan, spinal fluid examination, nerve conduction test examination, nerve conduction test (electromyography, or EMG), (electromyography, or EMG),

The most direct way to confirm the diagnosis is The most direct way to confirm the diagnosis is to demonstrate the botulinum toxin in the to demonstrate the botulinum toxin in the patient's serum or stool by injecting serum or patient's serum or stool by injecting serum or stool into mice and looking for signs of botulismstool into mice and looking for signs of botulism

The bacteria can also be isolated from the stool The bacteria can also be isolated from the stool of persons with foodborne and infant botulismof persons with foodborne and infant botulism

These tests can be performed at some state These tests can be performed at some state health department laboratories and at CDChealth department laboratories and at CDC

BOTULIN TOXIN (BOTULIN TOXIN (cont.cont.))

Home preserves (pH 5 and above) Home preserves (pH 5 and above) frequent source of botulismfrequent source of botulism

Not formed in pH below 4.7Not formed in pH below 4.7Molds may shift pH to above 4.7Molds may shift pH to above 4.7Destroyed by boiling 10 minDestroyed by boiling 10 minTreatment of BotulismTreatment of Botulism NONE NONE

BOTULISM PREVENTIONBOTULISM PREVENTIONPreservation of foods at pH Preservation of foods at pH

below 4.7below 4.7Salt (brine) and sugarSalt (brine) and sugarNitrites in cured foods Nitrites in cured foods

(remember the nitrites/nitrates in (remember the nitrites/nitrates in hot dogs, cured ham, processed hot dogs, cured ham, processed meats)meats)

Boiling food 10 min Boiling food 10 min

INFANT BOTULISMINFANT BOTULISM

Predominant form in the USAPredominant form in the USA75-100 cases/year in the USA75-100 cases/year in the USA

INFANT BOTULISM (INFANT BOTULISM (cont.cont.))Less than 6 months old childrenLess than 6 months old childrenAssociated with ingestion of honeyAssociated with ingestion of honeyHoney has endospores in it Honey has endospores in it

naturallynaturally bees pick up the bees pick up the endospores from the flowersendospores from the flowers

Immature intestinal microflora of Immature intestinal microflora of infants leads to infant botulisminfants leads to infant botulism

children may receive medical attention because children may receive medical attention because of symptoms such as of symptoms such as constipationconstipation, poor sucking , poor sucking action, a weak cry, and a general, progressive action, a weak cry, and a general, progressive muscle weakness. muscle weakness.

Infant botulism detection Infant botulism detection tests!!tests!!

The diagnosis is confirmed by the The diagnosis is confirmed by the detection of the organism or its toxin detection of the organism or its toxin in the infant’s stoolin the infant’s stool

Toxin isolation and identification are Toxin isolation and identification are accomplished via mouse lethality accomplished via mouse lethality testing, with typing (type C or D testing, with typing (type C or D toxin) confirmed by neutralization of toxin) confirmed by neutralization of toxin by specific sera (antibodies—toxin by specific sera (antibodies—immunoglobulins) immunoglobulins)

Where are these endospores Where are these endospores commonly found?commonly found?

More than 90% of reported cases More than 90% of reported cases (infant botulism) in the USA come (infant botulism) in the USA come from California, Utah, and southeast from California, Utah, and southeast Pennsylvania; this is likely a Pennsylvania; this is likely a consequence of high concentrations consequence of high concentrations of of C. botulinumC. botulinum spores in the soil of spores in the soil of these regionsthese regions

WOUND BOTULISMWOUND BOTULISM

C. botulinum C. botulinum develops in develops in grossly contaminated wounds grossly contaminated wounds

19 cases in 199519 cases in 1995Very common with black tar Very common with black tar

heroine users/skin poppingheroine users/skin popping

blepharospasm and strabismus BOTOX

Therapeutic use of botulinum Therapeutic use of botulinum toxintoxin

What is Blepharospasm?

Blepharo means "eyelid". Spasm means "uncontrolled muscle contraction".

The term blepharospasm can be applied to any abnormal blinking or eyelid tic or twitch resulting from any cause, ranging from dry eyes to Tourette's syndrome to tardive dyskinesia.

What is Strabismus?What is Strabismus?

Strabismus, also known as crossed or turned eye, is the medical term used when the two eyes are not straight. It occurs in approximately 2% to 4% of the population.

                                                                 

GAS GANGRENEGAS GANGRENE

GAS GANGRENEGAS GANGRENETissue necrosis (death) from lack Tissue necrosis (death) from lack

of blood supplyof blood supplyCaused by Caused by C. perfringensC. perfringensNeglected wounds (anaerobic Neglected wounds (anaerobic

conditions) provide a suitable conditions) provide a suitable environment for environment for C. perfringens C. perfringens growthgrowth

Clostridium perfringens

Gas gangrene

GAS GANGRENE (GAS GANGRENE (cont.cont.)) Highly lethal if untreatedHighly lethal if untreated C. perfringens C. perfringens ferments muscle proteins ferments muscle proteins

and carbohydrates producing Hand carbohydrates producing H22 and CO and CO22

Predisposing factors:Predisposing factors:

Dirt in woundDirt in woundLong delay before wound careLong delay before wound careInduced abortionInduced abortion

GAS GANGRENE (GAS GANGRENE (cont.cont.))

Predisposing factors:Predisposing factors:ArteriosclerosisArteriosclerosisDiabetesDiabetes

Gas gangrenein arm

Bone fracture withgas in surroundingmuscular tissue

Gas gangrenein foot

Gas gangrenein foot

Gas gangrene in buttocks

TREATMENTTREATMENT

Removal of necrotized (dead) tissueRemoval of necrotized (dead) tissueAmputationAmputation

Hyperbaric OHyperbaric O22

AntibioticsAntibiotics

Hyperbaric chamber forgas gangrene treatment

AnthraxAnthrax

AnthraxAnthrax Caused by Caused by Bacillus anthracis Bacillus anthracis (aerobic;G+; (aerobic;G+;

endospore former)endospore former)commonly found in the soil (South and commonly found in the soil (South and

Central America, Southern and Eastern Central America, Southern and Eastern Europe, Asia, Africa, Caribbean and the Europe, Asia, Africa, Caribbean and the Middle East)Middle East)

primary disease of domesticated and wild primary disease of domesticated and wild animals-particularly herbivoresanimals-particularly herbivores

humans become infected when they come humans become infected when they come into contact with diseased animals (flesh, into contact with diseased animals (flesh, bones, hides, hair and excrement)bones, hides, hair and excrement)

Robert Koch-1876, 1877 Robert Koch-1876, 1877 isolated and obtained a pure isolated and obtained a pure cultureculture

Louis Pasteur-1881, developed Louis Pasteur-1881, developed a vaccinea vaccine

Robert KochRobert Koch

Koch was a doctor and he had a detailed Koch was a doctor and he had a detailed knowledge of the human body – something knowledge of the human body – something that Pasteur, as a research scientist – that Pasteur, as a research scientist – lacked. lacked.

He was also skilled in experiments, the He was also skilled in experiments, the result of his work in natural sciencesresult of his work in natural sciences

Qualities that also proved to be important Qualities that also proved to be important were his ability to work for long periods of were his ability to work for long periods of time and his patiencetime and his patience

However, Koch was also difficult to work However, Koch was also difficult to work with and could not tolerate anyone telling with and could not tolerate anyone telling him that his theories were wronghim that his theories were wrong

Robert KochRobert Koch

In 1872, Koch became district In 1872, Koch became district medical officer for a rural area near medical officer for a rural area near Berlin. He started to experiment with Berlin. He started to experiment with microbes in a small laboratory he microbes in a small laboratory he had built for himself in his surgery.had built for himself in his surgery.

Anthrax vaccine--PasteurAnthrax vaccine--Pasteur

In France at that time many cattle suffered In France at that time many cattle suffered from from anthrax,anthrax, a serious disease from a serious disease from which many of them died. which many of them died.

after many experiments Pasteur after many experiments Pasteur succeeded in producing a weakened & succeeded in producing a weakened & harmless culture of anthrax bacteriaharmless culture of anthrax bacteria

He inoculated cattle & sheep with this He inoculated cattle & sheep with this giving them a mild form from which they giving them a mild form from which they recoveredrecovered

When these animals were introduced with When these animals were introduced with others who had a severe form they others who had a severe form they remained unaffected. They were immune.remained unaffected. They were immune.

Gram Stain-Gram Positive

Robert Koch’s Photos

Human cases of Anthrax are rare: Human cases of Anthrax are rare: 1/100,000 risk1/100,000 risk

Three forms:Three forms:Cutaneous-Most common formCutaneous-Most common form

acquired through a cut or abrasion of the acquired through a cut or abrasion of the skin, which comes into contact with spores skin, which comes into contact with spores from the soil or a contaminated animalfrom the soil or a contaminated animal

Inhalation-Inhalation-acquired by the inhalation of spore-acquired by the inhalation of spore-

containing dust where animal hair or hides containing dust where animal hair or hides are handledare handled

Intestinal- (Speculated)Intestinal- (Speculated)consumption of contaminated meatconsumption of contaminated meat

Cutaneous-Spores germinate, vegetative cells Cutaneous-Spores germinate, vegetative cells multiply and a lesion (black=necrotic tissue) multiply and a lesion (black=necrotic tissue) develops at the site of infectiondevelops at the site of infectionExtreme cases involve bacteria in the Extreme cases involve bacteria in the

bloodstream which can be fatal (25%)bloodstream which can be fatal (25%) Inhalation-Symptoms may resemble a common Inhalation-Symptoms may resemble a common

cold, progressing to abrupt fever and chest cold, progressing to abrupt fever and chest pain. After several days, severe breathing pain. After several days, severe breathing problems and shock, resulting in death problems and shock, resulting in death (hemorrhage)—leads to 100% death if left (hemorrhage)—leads to 100% death if left untreateduntreated

Intestinal-Inflammation of the intestinal tract, Intestinal-Inflammation of the intestinal tract, nausea, loss of appetite, vomiting, severe nausea, loss of appetite, vomiting, severe diarrhea and death (25-60%)diarrhea and death (25-60%)

Cutaneous Anthrax

Treatment:Treatment:AntibioticsAntibiotics

Effective if given within 24 hours, or before Effective if given within 24 hours, or before the bacteria enter the bloodstreamthe bacteria enter the bloodstream

Penicillin, Tetracyclines, fluoroquinolones Penicillin, Tetracyclines, fluoroquinolones (Cipro)(Cipro)

VaccineVaccineprotective antigen (composed of a fraction protective antigen (composed of a fraction

of the toxin)of the toxin)95% protective95% protective

*No evidence of person-to-person transmission *No evidence of person-to-person transmission

Anthrax Toxin-Symptoms and disease is Anthrax Toxin-Symptoms and disease is caused by a toxincaused by a toxinmade up of a protease (protein-digesting made up of a protease (protein-digesting

enzyme)enzyme) B. anthracisB. anthracis form endospores form endospores Spores may survive in the soil, water and on Spores may survive in the soil, water and on

surfaces for many yearssurfaces for many yearsDestroyed by autoclaving, burning, or Destroyed by autoclaving, burning, or

chlorination chlorination

Biological WarfareBiological Warfare Any disease-causing organism that is used as Any disease-causing organism that is used as

a weapona weapon Anthrax has particularly useful features to be Anthrax has particularly useful features to be

used as a weaponused as a weaponStable in the environment (endospores)Stable in the environment (endospores)spores that can be inhaledspores that can be inhaledonce spores are inhaled, vegetative cells once spores are inhaled, vegetative cells

grow and produce lethal toxinsgrow and produce lethal toxins