INFECTIONS AND ANTIBIOTICS

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INFECTIONS AND ANTIBIOTICS
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PATHOGENIC POTENTIAL OF MICROBES

• EXALTATION
• PATHOGENIC SYNERGY

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ASEPSIS

• SURGICAL RITUAL
• STERILIZATION
• Wet heat
• Dry heat
• Irradiation
• Special sterilizing chemicals, liquid
  or gases
• DISINFECTION

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SURGICAL INFECTION

• Infection,bacteremiasepticaemia
• Microbiological diagnosis of infection
• Wound infection
• Peritionitis
• Pelvic inflammatory disease
• Burns
• Pressure sores
• Sepsis, shock SIRS

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WOUND INFECTION

• FACTORS PREDISPOSING TO INFECTION
• contamination
• foreign material
• virulence enhancing effect of some
  materials,such as soil,calcium and iron .salts
• delay in primary intention
• Pathogenic synergy
• Dentalized tissue
• oedema / pressure / constriction
• impaired blood supply
• extravasation of tissue fluids blood
• host factors lowering resistance
• TISSUE OXYGENATION
• SYMPTOMS SIGNS OF INFECTION
• POST-OPERATIVE WOUND INFECTION

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ANAEROBIC INFECTION

• TETANUS
• GAS GANGRENE/OTHER CLOSTRIDIAL INFECTIONS
• PROGRESSIVE BACTERIAL GANGRENENECROTIZING
  FASCITIS
• OTHER ANAEROBIC INFECTIONS

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HOSPITAL-ACQUIRED(NOSOCOMIAL)INFECTIONS

• SITES OF COLONIZATION
• HAND-BORNE OR SURFACE-MEDIATED CHALLENGES
• AIRBORNE CHALLENGES
• INGESTED CHALLENGES
• INOCULATED CHALLENGES
• HAZARDS ASSOCIATED WITH INTENSIVE CARE

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ANTIMICROBIAL MANAGEMENT OF WOUND INFECTIONS

• ORGANISM FIRST CHOICE
  ALTERNATIVE
• Methicillin-sensitive Flucloxacillin
  Eryhthromycin,cefuroxime
• 
  
  Clindamycin
• Methicillin-resistant Vancomysin
  Telcoplanin,Linezolid
• Coagulase-negetive Vancomysin
  Telcoplanin
• Streptococcus pneumoniae Benzylpeniocillin
  Erythromycin,Cefuroxime
• 
  
  Ceftriaxone
• Streptococcus pyogenes Benzylpenicillin
  Erythromycin,clindamycin
• Streptococcus
  Amoxicillin Gentamycin
  with Penicillin
• 
  or
  Amoxicillin,Vancomysin
• Bacteroides species Metronidazole
  Co-amoxiclav,Clindamycin
• 
  
  Erythromycin
• Escherichia Coli
• -Sepsis Cefuroxime
  or gentamicin Ceftriaxone,ceftazidime,
• 
  
  Ciprofloxacin
• - UTI
  Trimethoprim or Amoxicillin
  Coamoxiclav,Cefuroxime
• 
  
  Cefotaxime,ceftazidine
• 
  
  Norfloxacin
• Haemophilus influenza Amoxicillin
  Co-amoxiclav,cefroxime

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PRINCIPLES OF GOVERNING THE CHOICE AND USE OF
ANTIBIOTICS

• INITIAL THERAPHY FOR ACUTE INFECTIONS
• Type of infection
  Antimicrobial
• Chest Infection
• ------------------
• Uncomplicated
  Amoxicillin,erythromycin
• Community-acquired pneumonia
  Cefuroximeerythromycin
• Hospital-acquired/post operative
  Ceftazidime/ciprofloxacinmetronidazole
• Aspiration pneumonia
  Coamoxiclav or amoxicillinmetronidazole
• Atypical or legionella likey
  erythromycin or tetracycline
• UTI
• ----
• Lower infection
  Trimethoprim/amoxicillin/cephalexin/nitrofurantoin
  
• Acute pyelonephritis
  Cefuroxime/Ceftriaxone/ciprofloxacin/gentamycin
• Wound Infection
• --------------------
• Abdominal and Pelvic
  Metronidazole with 2nd or 3rd generation
• 
  Cephalosporin or Benzyl Penicillin
• 
  Genatmycin
• If Staph.Aureus suspected
  Fluxacillin or Cefuroximeor Erythromycin

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PROPHYLACTIC USE OF ANTIBIOTICS

• SKULL FRACTURES MENINGITIS
• TETANUS
• GAS GANGRENE
• PREVENTION OF ENDOCARDITIS
• CLEAN SURGERY
• GASTROINTESTINALGENITOURINARY SURGERY
• TREATMENT OF COMPOUND LIOMB FRACTURES
• PROSTHETIC IMPLANTS

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MANAGEMENT OF IMMUNOSUPPRESSED PATIENTS(including
those who had splenectomy)

• PROPHYLAXIS
• TREATMENT ( A combination of Aminoglycoside with
  an antipseudomonal Penicillin or Cephalosporin is
  recommended for immunosuppressed patient )

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INFECTION ANTIBIOTICS

• Clinical Scenarios

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• A 53 year old woman develops a swing pyrexia five
  days after an eventful cholecystectomy. On
  examination the wound appears inflammed, and
  there is oozing of pus from the upper end. Gram
  stain of the pus reveals Gram-positive cocci in
  cluster, with pus cells present
• a)What is the likely organism?
• b)What antibiotic is likely to be helpful?
• c)What other intervention may be necessary?

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• A 70 year old man who is awaiting surgery for an
  enlarged prostate is admitted from home having
  been found collapsed by neighbours. He is
  confused and unable to give a history.
  Examination reveals only mild suprapubic
  tenderness, other systems are clear. He is
  pyrexial and hypotensive.
• What is the likely diagnosis?
• What is the likely organism?
• What other intervention might be necessary?

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• A 65 year old man is transferred to ITU for
  ventilation after a difficult hemicolectomy.
  After three days of ventilation, he develops a
  low-grade pyrexia, rising white cell count and
  increased oxygen requirement.He had received
  treatment with amoxycillin for his chronic
  bronchitis before admission, and had prophylaxis
  with a second generation cephalosporin and
  metronidazole preoperatively. A tracheal
  aspirate shows moderate number of pus cells and
  Gram-negative bacilli.
• What is the likely organism?
• What antibiotic would be most suitable for
  treatment?