HOSPITAL

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HOSPITAL COMMUNITY ACQUIRED INFECTIONS

• Assist Prof Dr.
• Syed Yousaf Kazmi

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OBJECTIVES

• Define Community Hospital Acquired infections
• Discuss the pathogenesis of community hospital
  acquired infections
• Discuss the etiology epidemiology of community
  hospital acquired infections

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COMMUNITY ACQUIRED INFECTIONS

• An infection contracted outside of a health care
  setting or an infection present on admission
• http//medical-dictionary.thefreedictionary.com/c
  ommunity-acquiredinfection
• An infection acquired in the community
• http//www.medterms.com/script/main/art.asp?articl
  ekey38208

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HOSPITAL ACQUIRED INFECTION (NOSOCOMIAL INFECTION)

• A hospital-acquired infection is usually one
  that first appears three days after a patient is
  admitted to a hospital or other health care
  facility
• http//medical-dictionary.thefreedictionary.com/Ho
  spital-AcquiredInfections
• An infection acquired in a hospital by a patient
  who was admitted for a reason other than that
  infection
• WHO

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HOSPITAL ACQUIRED INFECTION (NOSOCOMIAL INFECTION)

• An infection occurring in a patient in a
  hospital or other health care facility in whom
  the infection was not present or incubating at
  the time of admission
• WHO Definition

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COMMUNITY ACQUIRED INFECTIONS

• For infection to occur, susceptible host,
  pathogen and mode of transmission all must act
  together
• Yellow fever prevalent in Africa America but
  not in Asia(Pathogen Not present)
• In Europe/ Scandinavian countries-No case of
  Diphtheria (No susceptible host)

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COMMUNITY ACQUIRED INFECTIONS

• All infections that we acquire in community
• RTI (Sinusitis, Pharyngitis, Pneumonia etc.)
• GIT Infection(Ac GE, Dysentery, etc.)
• UTI (Cystitis, pyelonephritis etc.)
• CNS infections (Meningitis, Brain abscess)
• Skin soft tissue infection (Boil, Impetigo,
  Cellulitis, Herpes simplex)

Herpes labialis
Boil due to Staph aureus
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COMMUNITY ACQUIRED INFECTIONS

• Causative organisms of Community Acquired
  Infections are different from Hosp Acq Inf
• Most infections are viral esp. Respiratory Tract
  Infections
• Bacterial pathogens are usually susceptible to
  multiple conventional antimicrobials
• Highly resistant organisms e.g. MRSA, VRE, MDR TB
  are acquired from community in low frequency

Lobar pneumonia
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COMMUNITY ACQUIRED INFECTIONS

• RESPIRATORY TRACT INFECTIONS
• Upper RTI-mostly viral (Adenovirus, Rhinovirus,
  Coronavirus etc.)
• Lower RTI-mostly bacterial (Strep pneumoniae,
  Haemophilus influenzae, Mycoplasma pneumoniae,
  Legionella pneumophila etc.)
• Acquired from other patients through droplet
  infection
• Strep pneumoniae-from oropharynx

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COMMUNITY ACQUIRED INFECTIONS

• GIT INFECTIONS
• Bacterial (Shigella, Campylobacter, Vibrio
  cholerae etc.), Parasitic (E
  histolytica, Giardia, etc.)
• Feco-oral route in community setting e.g. school,
  campus, etc.
• UTI
• Mainly female
• Usually pregnant
• Bacteria (E coli 75, Klebsiella, Proteus spp.)

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• VIDEO

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MCQ

• A 32-years-young pregnant lady in her second
  trimester complained of burning frequency of
  micturition with haematuria. Her urine RE reveal
  multiple pus cells. The culture of the urine will
  most likely isolate which of the following
  pathogen?
• Proteus mirabilis
• Pseudomonas aeruginosa
• Serratia marcescens
• Escherichia coli
• Staphylococcus aureus
• Correct answer d

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HOSPITAL ACQUIRED INFECTIONS

• Infections acquired while in the hospital
• Excludes all disease that patient is incubating
  during admission (e.g. Chicken pox incubation
  period is 10-21 days)
• Hospital acquired infections are different from
  community acq inf

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HOSPITAL ACQUIRED INFECTIONS

• The host is usually immunocompromised of varying
  degree
• Pathogens encountered in the hospital settings
  are different
• Mean of transmission in hospital setting are also
  different from community setting

Common Hospital acquired infections
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HOSPITAL ACQUIRED INFECTIONS

• COMPROMISED HOST
• Some form of physical injury
• Burn, trauma etc.-bacteria can enter body
• Low immunity-body own flora cause disease e.g.
  Candida infection of GIT

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HOSPITAL ACQUIRED INFECTIONS

• HOSPITAL PATHOGENS
• Pathogens from other patients, healthcare staff,
  environment etc
• Opportunistic pathogens of own flora
• Pathogens are multiple antimicrobial resistant
• MRSA, VRE, MDR pathogens common

Microorganism of total infection
Coagulase neg staphylococci 15.3
Staphylococcus aureus 14.4
Enterococcus spp. 12.1
Candida spp. 10.7
Escherichia coli 9.6
Pseudomonas aeruginosa 7.9
Klebsiella pneumoniae 5.8
Enterobacter spp. 4.8
Acinetobacter baumannii 2.7
Klebsiella oxytoca 1.1
Top 10 infectious agents in Hospital acquired
infections Source CDC 2008
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HOSPITAL ACQUIRED INFECTIONS

• CHAIN OF TRANSMISSION
• Direct contact b/w patients, visitors, healthcare
  staff
• Indirect contact-through dust, environment,
  equipment etc.
• Indwelling equipment most imp source-urinary or
  I/V catheters, ventilators, N/G tube, etc.

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HOSPITAL ACQUIRED INFECTION

• VIDEO

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HOSPITAL ACQUIRED INFECTION

• HOSPITAL ACQUIRED UTI
• Mostly catheter related
• Enterococcus sp., Pseudomonas aeruginosa., E
  coli, Staphylococcus sp., Candida spp .
• Multi-drug resistant

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HOSPITAL ACQUIRED INFECTION

• HOSPITAL ACQUIRED RTI
• Micro-aspiration of upper airway secretions
• Ventilator associated, ET intubation associated
• Pseudomonas aeruginosa, E coli, Klebsiella
  spp., Acinetobacter baumannii, Haemophilus
  infleunzae, etc.
• Usually multidrug resistant isolates

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HOSPITAL ACQUIRED INFECTIONS

• SURGICAL SITE INFECTIONS
• Infection of surgical incision
• Mostly by Staph aureus, Enterococcus, Pseudomonas
  aeruginosa, E coli, Anaerobes etc.
• Pathogens transmitted by healthcare staff hands,
  dirty equipment, etc

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HOSPITAL ACQUIRED INFECTIONS

• Prolonged Hospital stay
• Increased morbidity
• Mortality
• Many infections are preventable
• Economic burden due to antimicrobial
  administration hospital stay
• Acquisition of drug resistance spread of
  virulent pathogens

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THANK YOU