Download Big Bad Bugs in the Dialysis Unit

Big Bad Bugs in the
Dialysis Unit
Douglas Shemin, MD
Kidney Diseases and Hypertension
Division, Rhode Island Hospital
Big Bad Bugs
1. MRSA
2. VRE
3. C. diff
Microbiology: study of
microscopic living organisms
Algae
Protozoans
Fungi
Viruses
Bacteria: one cell structure, have
cell walls
5,000,000,000,000,000,000, 000,000,000,000
bacteria in the world!
cocci
rods
Gram staining of
bacteria
Gram positive
Gram negative
Classification of
bacteria
• Gram positive
cocci
• Gram negative
cocci
• staphylococcus
• streptococcus
• enterococcus
• Neisseria gonorrhea
• Gram positive
rods
• Pseudomonas
• E. coli
• Vibrio cholera
• clostridia
• Gram negative
rods
Staphylococcus
Colonize skin and soft tissue
Staph epidermidis (coagulase
negative)
Staph aureus (coagulase positive):
1940s: treated with pencillin
1970s: treated with methicillin
1990s: methicillin resistant (MRSA)
MRSA
Introduced into health facilities from
endemic areas (nursing homes,
hospitals) or by HCWs
Rapidly disseminates and colonizes
patients (especially with skin
diseases or breakdown) and HCWs.
Also lives on machinery,
environmental surfaces
Risk of colonization highest in elderly,
in ICU patients, HD patients
MRSA in hemodialysis
patients: CDC, 2005
813/5287 invasive MRSA cases in 2005
in HD patients (15 % of the total)
45.2 cases invasive MRSA/1000
dialysis patients: 100 times greater
risk
70 % cases in patients > 70
85 % cases in patients with catheters
In hospital death rate with invasive
MRSA: 17 %
Treatment of MRSA
Vancomycin historically agent of
choice
Newer agents: linezolid,
daptomycin
But: look out for VRSA (first
reported in 2002 in a patient on
long term hemodialysis
Control of MRSA
Screening for carriage with swabs
from nares and skin lesions
Isolation techniques—handwashing,
gloves, gowns, masks
Eradication of the carrier state (with
intranasal or topical mupirocin
(Bactroban)
Enterococcus
Enterococcus are gram positive cocci
Normally reside in gastrointestinal
tract (feces, mouth and pharynx) and
vagina
Historically susceptible to
vancomycin; VRE (vancomycin
resistant enterococcus) reported in
1989
VRE
Found in stool
Risk factors: chronic illness,
kidney failure, long hospital
stays, use of antibiotics
VRE is resistant to virtually all
antibiotics: penicillin,
cephalosporins, sulfa,
quinolones
Prevention of VRE
Avoidance of use of vancomycin
(use of cefazolin for treatment of
staph infections instead, or
waiting for culture results
before starting antibiotics)
Treatment of VRE
Control of VRE
Screening for carriage with stool
cultures
Isolation techniques—
handwashing, gloves, gowns,
designated equipment
Stricter isolation with diarrhea or
incontinence
Clostridium difficile
(c.diff)
Gram positive rod
Usually associated with membrane
formation in colon
(pseudomembranous colitis)
Clinical manifestation: diarrhea
Always associated with previous use
of antibiotics
Diagnosed by c. difficile toxin in stool
Pseudomembranous colitis due to c.diff infection
Pathogenesis of c. diff
1. Use of antibiotics that alter
the intestinal flora in the colon
2. Age or illness related
susceptibility: geriatrics,
immunosuppression, poor
nutrition
Symptoms of c. diff
infection
1. Fever, abdominal pain and
diarrhea soon after treatment
of an infection with an
antibiotic
2. Toxic megacolon can occur,
with colonic perforation
Treatment of c.diff
1. Prevention: avoidance of
unnecessary antibiotics
2. Stopping antibiotic once diagnosis
made
3. Oral vancomycin or metronidazole
(Flagyl)
4. No anti-diarrheal agents
5. Lactobacillus tablets may be
helpful
Big Bad Bugs: MRSA,
VRE, c. diff
1. All associated with
immunodeficiency, chronic illness,
and chronic kidney disease
2. All associated with antibiotic use
3. Although definitive treatment is
with antibiotics, the most effective
treatment is prevention, with
isolation techniques and
handwashing
What can you do to
protect your patients?
1. Protect yourself: cooperating with
isolation and gowning/gloving
procedures
2. Educate your patients: isolation
techniques decrease trasnmission
3. Educate patients and families:
antibiotics can have significant
negative consequences