Clostridium Flashcards
Gram ________
Spore?
Capsule?
Motile?
Gram +ve rods
Spore forming
Non capsulated
Motile : Peritrichous flagella(except C.pefringens and Tetani)
Clostridium has Peritrichous glagellea except
Perfrimgens and Tetani
Spores of which Clostridium seen in Ellners medium
C.perfringens
Heat susceptible excetp
Perfrimgens type A and Botulinum
Spore position
Subterminal
Central
Terminal
Subterminal : Per and bot
Terminal : Tetani and diff
Cultivation of which organism requires Mcintosh Fildes jar (anaerobic)
Clostridium
Clostridium cultivation
Robertsons cooked meat brother
Clostridium is Reverse Camp or Camp test +ve
Reverse
Campt test +ve :
S. Agalctiae x S. Aureus
Listeria x S. Aureus
Toxins
Alpha toxin is demonstrated by
Exo ( minor and major)
Naglers reaction (lecithinase activity seen)
Gas gangrene
Aka
Cause m/c
Cause of death
Diagnosis
Tx
Anaerobic myonecrosis
M/c cause : Type A C.perfringens
Cause of death: circulatory failure
Dx : exudates— gram stain, culture
Tx : Surgical exploration + debridement.
Antibiotics Parenteral Penicillin+ Clindamycin+ hyperbaric O2
Citron bodies seen in gram stain of which Clostridium
C. Septicum (leaf/spindle shaped)
Food poisoning
Cause :
Source :
Toxin
MOA of toxin
Dx
Tx
C.perfringens type A
From meat brother with spores
Enterotoxin at GI tract
Toxins —–> pores —-> increased permeability —–> abdominal cramps+ watery diarrhea
Elisa/pcr
Tx self limiting
Necrotising enteritis
Cause
Dx
Tx
Pork contaminated with spores of Type C C perfringes
Pork + sweet potato
Elisa PCR (beta toxin in stool)
Tx Penicillin and metronidazole IV + fluids+ electrolytes
Hospital acquired diarrhea
Clostridiodes (clostridium)difficile
Rho proteins —-> glycosylated by toxins—-> disruption of actin and cytoskeleton —-> necrosis + apoptosis of colonic epithelium
Risk factors :
Ampicillin ephalosporins, Clindamycin , FQs
Clinical features
Antibiotic association colitis : Watery diarrhea +- Abdominal cramps + fever
Psudomembranous colitis :
Necrosed epithelial cells+ fibrin + pus cells
Tx
Initial:
Oral vancomycin or fidaxomici
Fulminant :
Oral vancomycin+ IV metronidazole
Features of C botulinum
Motile
Robertson cooked medium
Subterminal spores
Bottle= roberts cook
Botulinum toxin
Most potent
Exo toxin ( released on lysis of bacteria)
Toxin MOA site of action
Protoxon —-> Heavy chain proteolyse SNARE protein —–> failure of synaptic fusion complex —–> Ach not released
Site :
NmJ
Autonomic ganglion
Parasymp post gang
Symp post gang
Botulism
Clinical
Food borne (home cooked preserved» industrial canned)
- Nausea, vomiting, diarrhoea
- Cranial palsy (diplopia, dysphagia, dysarthria, dry mouth, dilated pupils)
- Autonomic syms: Urinary and constipation
- No fever, altered matation
Types of botulism infant
Infant (m/c) : FLOPPY BABY SYNDROME
Spores contaminated honey /milk , inhalation of spore.
Constipation, poor feeding , loss of head control, drooling
Wound
Skin popping ( intradermal injection of heroin)
Spores contaminate wound —-> vegetative bacteria—–> lysis —-> toxin
