CLOSTRIDIA SPECIES

AnO2, Gram +, motile rodsSaprophytes…soil, gut

animals/humans

organisms

• Botulism• Gas gangrene• Pseudomembranous colitis• Tetanus

Morphology/ culture

• Spores: wider than diameter of bacillus• Position: centre, terminal, subterminal• Motile: peritrichous flagellae• CULTURE: AnO2, BA• COLONIES: SMALL, LARGE, HEMOLYSIS• GROWTH: Sugar fermentation, protein

digestion, milk stormy fermentation ie clot torn by gas

• ENZYME : Different

CLOSTRIDIUM BOTULINUM

• Botulism• World-wide• Soil, rarely animal feces• Spores: heat resistant 100 C many hours• R decreased by acid, salt• TOXIN: Released on growth, autolysis• Ag types: A-G• Human pathogen ; A,B,E

TOXIN ….CONTD

• A……FOODS• E…..FISH• C ….BIRDS• D…..MAMMALS• MOL. WT: 150,000( 100,000 &50,000 fragments by

s-s bond• Absorbed by gut• Bind to pre synaptic memb of motor neurons• Cranial nerves, PNS

toxin

• Neuron proteins( SNARE) inhibit release of Ach at synapse

• Lack of muscle contraction….paralysis• Most lethal toxin: 1-2ug• Destroyed by heat at 100 for 20min

PATHOGENESIS

1. FOOD: Intoxication; not infection• Canned, alkaline, eaten raw, • Vacuum packed, spiced, smoked• Spores: germinate, release toxin in AnO2• Ach release blocked and FLACCID PARALYSIS2. WOUND: A&B

CLINICAL FINDING

• Food ingestion…..18-24 hrs• Visual disturbance: in-coordination of eye muscle,

double vision• Speech difficulty• Swallowing difficulty• Bulbar paralysis• Death, respiratory/cardiac arrest• Pt conscious till death• Fever; absent, no anti-toxin in blood if recovery

INFANT BOTULISM

• Common in US• Food ingestion• Floppy baby: poor feed, weak, paralysis• Honey; vehicle• Feces: CB, toxin • Serum: none

Lab diagnosis

TOXIN: in serum & food left overs Mice: I/P injection; death Ag type: neutralization in miceCULTURE: Food remains test for toxin; RIA, Hagglut.Infant: bowel, toxin & CB; not in serum

TREATMENT

1. TRIVALENT ANTI-TOXIN• 3 potent anti-toxins; A,B,E• Prepared in Horses• GIVE I/V2.Mechanical respiration• Mortality brought downINFANTS:• Recover on support• Anti-toxin given

EPIDEMIOLOGY

• SOIL; vegetables, fruits,• Canning; destroy spores,• boil ; 20 minutes before use• Home canning: beans, corn, peppers,

olives, peas, fresh fish, smoked fish• TOXIC: spoiled, ranscid, swelled cans• Toxoids: for cattle• Bioterrorism, warfare

CLOSTRIDIU TETNAI

• Soil• Animal feces• O Ag –same• Flagellar- several• Toxin- same, neurotoxin• TOXIN: Tetanospasmin• MW: 1,50,000(100,000 & 50,000); s-s bond• Motor neurons: Binds pre-synaptic membranes• Retrograde axonal movement to neurons SC, B STEM

• Toxin moves to inhibitory cells, degrades synaptobrevin, a protein that docks vesicles to pre synap memb.

• Release of inhibitor is blocked & cells are not inhibited

• Hyper-reflexia & muscle spasm ensues• V. small amounts may be lethal

PATHOGENESIS

• SITE: devitalized tissue, AnO2 • Wound• Umbilical stump• Burn• Injury• Surgical suture• TOXAEMIA, little infection• Spore germination; necrotic tissue, Calcium

salts,pyogenic infection; ow oxid-reduction• Toxin released, travels & fixes to receptors in CNS

CLINICAL FINDINGS

• Incubation: 4-5 days….weeks• Tonic contraction of voluntry muscles of• Injury• Jaw…lock jaw• Tetanic spasm on external stimulus• Painful• Conscious• Death…resp failure• High mortality

DIAGNOSIS

• H/O injury• d/d strychnine poisoning• Culture• Anti-toxin givenPREVENTION:• Active immunization by TOXOID• CARE OF WOUND WITH SOIL CONTAMINATION• PROPHYLACTIC USE OF ANTI-TOXIN• PENCILLIN

1.Human anti toxin or Tetanus immune globulin• 250-500 units I/M….2-4 weeks OR• 3000-10,000units to N unbound toxin• Neutralizes toxin fixed to nervous tissue2.Active immunization also doneMuscle relaxants, sedationAssisted ventilationSurgical debridementPencillin; prevent CT growth & super added infectionImmunized individual: TOXOID; recall injection

CONTROL

• Preventable• Universal Immunization: TOXOID• Formalin treat toxin; concentrate• AL –salt adsorbed toxoids usedchild: 1 st year• 3 injections• Booster: after 1 year• then before school entry• 10 years apart• Maintain serum level at 0.01units/ml• Children : DPT

clostridia

• C perfringens• C novyi• C histolyticum• C septicum

CLOSTRIDIA PERFRINGENS

• INVASIVE INFECTION• Myonecrosis• Gas gangrene• TOXINS:• Spreading infection• Lethal, necrotizing, hemolytic• Alpha toxin: lecithinase; splits CM lecithin• Theta toxin: hemlytic, necrotic• DNAse, hyalouronidase: digest collagen of s/c, muscle

• FOOD POISONING: ENTERO-TOXIN, meat dishes 108cells ingested, diarrhea in 6-18 hrs; hyper-sec in jej, ileum, self limiting

• Rarely n,v, fever • PATHOGENESIS• TRAUMA• Spore contamination….soil/intestine• Spore…germinate in low o-r potential; CELLS MULTIPLY• CHO fermented,gas produced,blood supply obst

• Spreading factors released• Tissue necrosis increases, increased bacterial growth,

hemolytic anemia, toxaemia, death• Gas gangrene, myonecrosis, mixed infection occurs by

toxigenic clostridia• Proteolytic clostridia, cocci, gram negative organisms• Genital tract: 5% femalesabortion associated• C sordelli: endometrial infection, • bacteraemia if neoplasia• C perferingens type C: children necrotizing enteritis; TOXOID

helps

CLINICAL FINDING

CONTAMINATION…..WOUND, UTERUS….1-3 days crepitations in S/C tissue, muscle…foul discharge…necrosis..fever, hemolysis, toxaemia, shock..death

Cellulitis, fascitisTREATMENT: Amputation Anti-bioticFood poisoning; spores germinate in warmed

meat dishes, toin, diarrhea lasts 1-2 days

LAB TESTS

SPECIMEN:• Wound• Pus• Tissue• Gram’s: + rods, spore?• Met glucose medium• BA AnO2: colonies;heolysis, I/D by biochemicals• Milk: clot-torn by gas in24 hrs• Egg-yolk medium: lecitjinase ppt around colonies• Toxin checked; neutralized by anti-toxin

TREATMENT

• Surgical debridement: prompt, extensive• AB; Pencillin• Hyperbarric oxygen• Anti-toxins as conc. Immune globulin• Food poisoning: symptomatic managemnt• PREVENTION: • EARLY, ADEQUATE CLEANSING• SURGICAL DEBRIDEMENT• AB. PENCILLIN

CLOSTRIDIUM DIFFICILE

• DIARRHEA: AB given esp AMP, CLINDAMYCIN• C difficile toxin in stool• Endoscopy: pseudomembrane• localized…… plaques, microabscesses• SYMPTOMS: Diarrhea; watery, bloody• cramps • fever, leukocytosis• T/M: discontinue AB• Start V an, Metronidazole

PATHOGENESIS

• AB; R C difficile proliferate• Toxins: A….enterotoxin, cytotoxin bind to

brush border receptors• Toxin B: cytotoxin• Toxins in stool

AB –associated diarrhea

• Mild…moderate• Less severe than pseudoMC• 25%.....associated with C difficile