Download Nosocomial Diseases

Katie McIntyre
Kevin Jaggi
Maya D’Alessio
“An infection acquired in a hospital by a
patient who was admitted for a reason other
than that infection”
 Infections
acquired during a hospital stay
 If you didn’t walk in with it – it’s nosocomial
 Also known as hospital acquired infections
(HAI)
 A major factor in terms of cost and time for
the current health care system
 Roughly
1.7 MILLION HAIs a year in the USA
leading to 99,000 deaths
 Roughly one third of nosocomial infections
are estimated to be preventable
 Costs the USA between $4 billion and $11
billion per year
 Immune
suppression
 Major surgery/invasive procedures
 Prolonged use of invasive devices
(ventilators)
 Long hospital stays
 Major wounds
 Elderly/infants
 Antimicrobial therapies
 Chemotherapy
 Exogenous
cross-infection
 Endemic or epidemic exogenous
environmental infections
 Endogenous infection
 Indirect
or direct contact transmission
 Droplet transmission
 Airborne transmission
 Vehicle transmission (contaminated
medication or surgical equipment)
 Past


Infections were caused by pathogens of external
origins
Microorganisms not present in the normal flora
 Present

Opportunistic pathogens that are common in the
general population
 Shift
due to use of antibiotic treatments and
hygiene practices
 Pulmonary
Infection caused by
Mycobacterium tuberculosis – inhabits the
lung
 Leading cause of death by bacterial
infections in the world
 Person can be Tb (+) however may not
develop the actual disease

~10% of Tb infected patients actually get the
disease
 HIV
patients are at higher risk for TB
 Patients
who have latent TB infections can enter
the hospital
 If they become immunocompromised they go into
active disease and can spread it
 TB can spread through droplet contact to
surrounding patients and healthcare workers
 Recently TDR TB has been detected in India,
along with MDR and XDR TB
 TB treatment is long term and complicated
 Most
common nosocomial infection
 Bacterial Infection caused by E. coli


Gram Negative Bacteria
Normal flora in body, however, some can cause
infections such as E. coli 0157:H7 known as a
shiga producing toxin
 Affects
bladder, kidneys, urethra
 Women
are more prone than men
 Patients who have nerve damage around the
bladder are more prone
 Patients who have weakened immune
systems are more prone
 Patients in hospitals or care homes who use
catheters are more prone
 Bladder

Burning sensation while urination, fatigue, bloody
urine
 Kidney

Infections
Infections
High Fever, abdominal pain, chills
 Antibiotics


up to 14 days
Amoxicillin
Fluroquinolones
 Lots
of fluids is recommended
 2nd
most common nosocomial infection,
however has the highest mortality rate
 Pneumonia (infection of lungs), which
develops when a patient is hospitalized for
an extended period of time
 Caused by Psuedomonas aeruginosa,
Staphylococcus aeurus, and Entrobacter,
Acetinobacter
 Patients who are on ventilators for more than
48 hours are most at risk, followed by
patients in ICU and patients in post-op care.
 The
most common way to get pneumonia in a
hospital or long term care facility (old age
home) is through a ventilator

VAP (Ventilator associated pneumonia)
 ~86% of all VAP cases have occurred in ICU
wards
 Patients who have been hospitalized for more
than 5 days and have been on a ventilator for
more than 48 hours should be screened
 Hard
to distinguish
 However the following are the main
symptoms to look for
 Fever, sputum, change in the characteristics
(color, etc.) of the discharge over a period of
time, rapid or shallow breathing, hypoxia
 Blood tests- WBC count
 Chest X-rays- Infiltrates indicate pneumonia
 Bronchoscopy
 Reduction
of time the patient uses a
ventilator

New research on coating the endotracheal tubes
with silver or hexetidine, which prevents
bacteria to adhere to it
 Using
sterile fluid in the suction that is used
to clear the catheter
 Tilting the hospital bed 30-40° at all time to
reduce GI reflux
 Changing tubes and machines of the
ventilators frequently
 Includes
any S. aureus strain that is resistant
to penicillins and cephalosporins
 MRSA strains are not more virulent
 Infects respiratory tract, open wounds, the
sites of intravenous catheters and the urinary
tract
 Becoming resistant to vancomycin
 Human carriers
 Upon
admittance to the hospital, patient
history is taken
 If there is a potential that the patient is
carrying MRSA, they are swabbed for further
testing
 MRSA testing is not immediate
 Suspected patients are put on contact
precautions until the test results are
released
 Includes
bacterial strains of Enterococcus
that are resistant to vancomycin
 4%
of hospital nosocomial infections in US
 Spread
 Use
through fecal to oral route
of cephalosporins is a risk factor for VRE
infection
 Causes
severe diarrhea and intestinal disease
 Normally can’t compete with commensal
bacteria
 In a patient on antibiotics, the commensal
bacteria have been killed
 The use of fluoroquinolones and clindamycin
are strongly associated with cases of C.
difficile
 Can lead to pseudomembranous colitis, a
severe inflammation of the colon or toxic
megacolon which can be fatal
 Treatment
in mild cases of C. difficile can be
as simple as halting antibiotic treatment
 In more serious cases metronidazole is used
and vancomycin may be used as well
 Relapses of C. difficile have been reported in
up to 20% of cases
 Antidiarrheal drugs make the damage worse
 In Australia they are experimenting with
fecal bacteriotherapy
Pleomorphic gram negative bacillus
 Only rare cases of community acquired infections
 Preferentially colonizes aquatic environments
- in hospitalized patients it is commonly found
in their:
-sputum/respiratory secretions
-urine
-wounds
 Capable of long-term survival in hospital
environments
-contact patients via
-inanimate objects
-human reservoirs

 A.baumannii
is the most common species
associated with infection causing
opportunistic infections
 Predominant role as an agent of ventilatorassociated pneumonia

Can also cause




Bacteremia
UTIs
Secondary meningitis
Skin and wound infections
 Combination
therapy is generally required to
treat infections due to growing antibiotic
resistance
 In
the 1990s Candida albicans was
responsible for approximately 80% of
candidemias
 There has been a shift in the type of
Candidia infections away from C.albicans




C.albicans (48%)
C.glabrata (24%)
C.tropicalis (19%)
C.parapsilosis (7%)
 These
other species are less susceptible to
the commonly used azole antifungal agents!
 Compliance
with proper hand hygiene is
lower than 40% and leads to the transmission
of infections between patients
 Hand hygiene is simple
 In Ontario, hospitals must report their hand
hygiene compliance rates
 80% of hospital staff who dressed a MRSA
infected wound carried the bacteria on their
hands for THREE HOURS
 Private
rooms or cohorting
 Proper cleaning protocols, using bleach or
other heavy duter cleaners
 Frequent cleaning
 Replacing any damaged equipment
 Repainting of walls/surfaces
 Curtains and surfaces are depositories for
bacterial growth
 Depending
on the confirmed or suspected
illness patients on put on a specific
“precaution” guideline
 Contact
precautions
 Droplet
precautions
 Airborne
precautions
 Many
nosocomials are caused by ubiquitous
opportunistic pathogens
 Avoid hospitals when possible
 Hand
hygiene
 Avoid
antibiotics when possible