Transcript Infections in the Elderly

Infections in the Elderly
Jérôme Fennell, MB, MSc, PhD, FRCPath
[email protected]
Infections in Old Age
• Risk Factors of Old Age
• Common Infections of Old Age
– RTI: Pneumonia, Influenza, TB
– Skin and Soft tissue infections
• Shingles
• Leg Ulcers
– GIT: C. Difficile
– UTI: ESBLs
• Renal function and aminoglycoside and
glycopeptide dosing
Risk factors for Infections in the Elderly
Older, weaker, more at risk
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More comorbidities
Gradual deterioration of immune system with age
May be malnourished, poor accommodation
More likely to harbour resistant organisms as
more likely to have been
– Hospitalised
– in nursing home
– Exposed to multiple antibiotics
Cellular Immunity in the Elderly
• Altered T cell phenotype
  naïve T cells;  memory T cells
 Reduced T cell responses
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 response to TCR stimulation
 T cell proliferation
 expression of IL2-R
 IL2 production
Ginaldi et al 1999
Case History: December 1999
• 67 yr old woman
• PC: cough, left sided chest pain, rigors x
24h
• HPC: productive cough most mornings,
but increasingly purulent recently
• PMHx: MI 2 yrs ago, smoked 40/day until
then
On Examination:
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T: 40oC
Pulse: 130/min, BP: 145/90
Tachypnoea
PMHx: MI 2 yrs ago
smoked 40/day until then
• Resp exam suggestive of consolidation
Tests
• FBC, WCC
• WCC – 22, 90% neutrophils
• Sputum for
• Sputum – pus cells, gram
microscopy and positive diplococci
culture
• Blood culture
• CXR
• ABG
CXR
Gram
Sputum result
Sputum – pus cells, gram positive
diplococci…What does this tell us?
More than you think –
• No epithelial cells - suggests this is a
good specimen from lower RT so
should provide a good result on culture
• Gram positive diplococci likely to be?
Sputum Gram Stain
• No longer done routinely
• Not sensitive or specific enough
• Not recommended in IDSA CAP guidelines
• Guidelines now recommend another test
instead...
Urinary Antigen Testing
• All severe pneumonias should have urine test
for
– Legionella Urinary Antigen
– Pneumococcal Urinary Antigen
• Should also think of CXR, pulse oximetry, ABG,
Treatment
Pneumococcus
BenzylPen unless allergic or live in area
of resistance (Irish rate of resistance-?)
When cause unknown, use augmentin or
cefotaxime to cover Haemophilus
later…
IV BenPen
Transferred to ICU for ventilation because of
hypoxia
BCs – positive for S pneumoniae x2
WCC – 35
CXR – shows increasing consolidation and
pleural effusion
24 hrs later – Cardiac arrest – RIP
Next day S pneumoniae sensitivity available:
R- Penicillin
S – Erythromycin, Ceftriaxone
RTI in Elderly
• Strep. Pneumoniae
• Influenza Virus
• Recurrence of TB
• Normal causes of RTI
Pneumococcus
• Common cause of community acquired pneumonia
• Risk increased by smoking
• Often occurs as secondary pneumonia after influenza
infection
• More common during winter months
• Can also cause ENT, bacteremia and CNS infections
• Latest EARSS Resistance Rates for Ireland:
– Pen Non Susceptible 16.2%
– Erythromycin Resistant 14.1%
– Ceftriaxone/Cefotaxime Resistance Rare
Pneumonia Symptoms
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Fever (less common in those >75)
Cough with coloured sputum
Pleuritic chest pain, dyspnea
Altered mental function, particularly in the
elderly
• Increased or decreased WBC
Strep pneumoniae
• RTI: Amoxicillin/Clarithromycin if sensitive
• If infection severe or previous antibiotic
exposure, use IV Ceftriaxone or Cefotaxime
• Augmentin has no added benefit because
resistance is not due to B-lactamase production
but do to different Pen binding proteins
• In countries where Ceftriaxone resistance occurs
in significant numbers use IV Ceftriaxone and IV
Vancomycin empirically
Pneumococcal Pneumonia
• Elderly patients often have fewer or less
severe symptoms than younger patients
• Many community-acquired pneumonias are
perfectly treatable as outpatients by oral
antibiotics
• >90 polysaccharide capsular types
• HPSC Guidelines:
Pneumococcal Vaccines
2 types of pneumococcal vaccine:
1. Polysaccharide Pneumococcal Vaccine (PPV23)
– incorporates 23 of the most common capsular types which together
account for up to 90% of serious pneumococcal infections
– Only suitable for use in those ≥ 2 years of age
2. A conjugate 7 valent vaccine (PCV7) containing polysaccharide antigens
from the 7 most common serotypes conjugated to a protein (CRM 197)
has enhanced immunogenicity compared with the polysaccharide vaccine.
– immunogenic even in infancy
– active against approximately 70% of isolates causing invasive
disease, and against a significant number of penicillin-resistant
strains.
HPSC Groups Requiring Vaccination
At risk categories:
• Asplenia or reduced splenic dysfunction (e.g. splenectomy, sickle cell
disease and coeliac syndrome)
• Chronic renal disease or nephrotic syndrome
• Chronic heart, lung, or liver disease, including cirrhosis
• Diabetes mellitus
• Complement deficiency (particularly early component deficiencies C1,
C2, C3, C4)
• Immunosuppressive conditions (e.g. HIV, leukaemia, lymphoma,
Hodgkin’s disease) and those receiving immunosuppressive therapies
• CSF leaks either congenital or complicating skull fracture or
neurosurgery
• Intracranial shunt
• Candidate for, or recipient of, a cochlear implant
• Children under 5 years of age with a history of invasive pneumococcal
disease, irrespective of vaccine history.
Adults >65
• All should be offered single dose of
Pneumococcal Polysaccharide Vaccine (PPV23)
• Adults 65 years or older should receive a
second dose of PPV23 if they received vaccine
more than 5 years before and were less than
65 years of age at the time of the first dose.
CURB-65 Score
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Confusion – new onset
Urea - >7 mmol/l
Respiratory rate >30 breaths/minute
Blood Pressure <90/60
Age>65
Score:
0-1 – Treat as outpatient
2 – consider admission or follow closely as outpatient
> 3 requires hospitalization, mortality >17%
Influenza
• H1N1 flu pandemic declared over by WHO
• now seen as part of seasonal flu
• Current seasonal flu vaccine includes a H1N1
strain
• Primary Influenza A infection can present
abruptly as rapidly progressive diffuse
pneumonia with pulmonary haemorrhage
• More severe in elderly, may develop
meningoencephalitis or encephalitis
Influenza
• Treatment: Neuraminidase inhibitors such as oseltamivir
(PO) and Zanamivir (IV) given early in severe or at risk cases
• Often followed by secondary bacterial pneumonia e.g. S
pneumoniae, S aureus
• Vaccine less effective in elderly
• Adults over 50 should have annual vaccination
• Those in nursing homes and other long stay facilities should
also have annual vaccination
Another Case
• 82 year old woman with 2 months of cough,
fatigue, night sweats
• Poor response to Coamoxiclav, tetracycline
TB in Ireland
• Common in the 1950s
• Many people who were exposed/treated as
children then are now presenting with TB now
as their immune system wanes with age
Varicella Zoster Virus
• Cause of Chicken Pox and later Shingles
• Extremely infectious
• Can be severe and even fatal in immunocompromised
• Shingles not uncommon in elderly hospital patients, can
leave severe pain of post-herpetic neuralgia
• Pose an infection control risk to immunocompromised, and
non immune staff especially to non immune pregnant staff
Not routinely recommended in Elderly
Leg Ulcers
• As patients age, increasing peripheral vascular
disease and diabetes can predispose to venous or
arterial leg ulcers
• Wet
• Warm
• Oxygenated
• Below the belt
• So swabs will always grow something, often grow
patients bowel flora
• Treat only if infected!
Case History
• Anne, 74 yr old housewife
• PC: Elective total hip replacement – 3/7 ago
• PMHx: Hypertension, Gastric Ca 13 yrs ago
• 2/7 post op catheter specimen urine showed
high white cells, Mixed growth predominantly
gram negative bacilli
• Given Zinacef po x 5/7
Case History
• 3/7 after Zinacef started, complains of diarrhoea
Causes:
• Infectious? – Any other patients on ward
affected?
• Non-infective causes?
• Hospital food?
• Secondary to drugs:
– Antibiotic assoc diarrhoea?
– Clostridium difficile?
Case History
Investigations?
Stool Culture sent:
• Culture – NAD, no Salmonella, Shigella,
Campylobacter, or E coli 0157
• C diff toxin studies negative
Case History
What next?
Repeat C diff testing: Positive
Treatment?
Case History
• Treatment – po
metronidazole 250
mgs qds for 10/7
• Diarrhoea settles –
D/C home
• Seen in OPD:
What is C. difficile?
Gram positive bacillus
Clostridia = anaerobe
Forms spores
Spread by touch, faecal-oral route
Main sources are:
• asymptomatic carriers
• Contaminated environment
Resistance to Antibiotics
No antibiotic – no selection for resistant
organisms
sensitive
resistant
Resistance to Antibiotics
antibiotic – selects for resistant organisms
sensitive
resistant
Clinical Picture
• Clinical ranges from mild diarrhoea to lifethreatening colitis
• Occurs 1/7 to 6/52 after antibiotic exposure
• Get watery diarrhoea, lower abdominal pain,
blood pr
Clinical Picture
• Systemic symptoms: fever, anorexia, nausea
and malaise
• Severely ill may have no diarrhoea due to
toxic megacolon
• Complications: perforation, peritonitis – high
mortality
Risk Factors
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Age
Prior antibiotic use
Length of hospital stay
Other severe underlying disease
C diff strain
Antibiotic culprits
• Any – including metronidazole
• Main culprits include:
– Clindamycin
– Cephalosporins
– Quinolones e.g. Moxifloxacin, Ciprofloxacin
– Broad spectrum antibiotics – e.g. Augmentin,
Meropenem
Pathogenesis
• Disrupts normal bowel flora
• Many people especially neonates are colonised
but not infected.
• Carriers thought to have better immune
response, infected tend to have lower Ab
response
• Two potent cytotoxins, toxins A and B
• Can have colitis without pseudomembranes
Spore Formation
• Spores provide a method of survival when
environmental conditions are unsuitable
• Protect against ethanol, phenol,
formaldehyde, heat
• Killed by iodine, glutaraldehyde, hydrogen
peroxide, autoclaving
• Stomach acid kills 99% bacteria but doesn’t affect
spores
Pseudomembranous Colitis
• Due to Clostridium difficile toxins, rarely due to S. aureus
• Symptoms: diarrhoea +/- mucus or blood, abdominal pain,
tenderness, fever, dehydration, electrolyte disturbances
• Dx by toxin detection or by endoscopy (risk of perforation)
• Tx: Stop causative agent, give metronidazole or
Vancomycin PO for 10/7
Diagnosis
• Culture too slow and those that grow may not
express toxins
• Therefore do toxin testing by ELISA
• Pseudomembranes can be seen on
endoscopy
• Nursing nose!
• No point in testing if clinically well or still on
treatment
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O27 strain
Increasingly common
Associated with quinolone use
Higher mortality
Higher infectivity
Treatment
• Hydration, electrolytes
• Contra-indicated: Antiperistaltics, e.g. imodium
• Severe illness may require surgery esp if perforation
or toxic megacolon suspected.
• Probiotics??
Half of recurrences thought to be due to reinfection
rather than relapse.
Metronidazole resistance rare.
TX. MUST BE PO!
C difficile Treatment Guide – IDSA 2010
UTIs
• Men often have some degree of prostatic
obstruction
• As patients age greater risk of urinary and
faecal incontinence
• Nursing home/Hospital/Antibiotic exposure
predispose to resistant organisms
• Temptation to catheterise many of these
patients indefinitely, this sacrifices patient
outcomes for convenience
Epidemiology of Extended Spectrum BLactamases - Ireland
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AMNCH – Monthly ESBL Reports Q2
2007 – Q3 2010*
45
40
35
30
25
20
15
10
5
n = 760
2007
2008
2009
2010
EARSS Ireland 02-10 – E. coli
EARSS Quarterly Surveillance Reports – Quarter 1 2010, HPSC
ESBL Sample Type - AMNCH
Female: Male 3:2
Miscellaneous
21%
Sputum
7%
Blood
Cultures
4%
Urine
68%
AMNCH ESBL Age Distribution
80
70
Average Age:
Median Age:
60.1
66
60
50
40
30
20
10
0
0-9
10-19 20-29 30-39 40-49 50-59 60-69 70-79 80-89 90-99
Urinary E. coli Antimicrobial Resistance Over Time
100
90
80
70
60
Ciprofloxacin-R
Amikacin-R
50
Gentamicin-R
Nitrofurantoin-R
40
Trimethoprim-R
30
20
10
0
4
5 6
7
8 9 10 11 12 13 14 15 16 17 18
ESBL Resistance Rates
Susceptible (%)
Intermediate (%)
Blood
Blood
Urine
Blood
Urine
20 (5.5)
Urine
Resistant (%)
Amikacin
11 (78.6) 312 (86.4)
2 (14)
29 (8.0)
1 (7.1)
Gentamicin
9 (60.0) 254 (70.2)
1 (7)
3 (0.8)
5 (33.3) 105 (29.0)
15 (100) 302 (82.7)
Ciprofloxacin
0 (0)
62 (17.0)
0 (0)
1 (0.3)
Meropenem
15 (100)
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0 (0)
-
0 (0)
-
Trimethoprim
-
68 (18.6)
-
0 (0)
-
297 (81.4)
Nalidixic Acid
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43 (11.8)
-
1 (0.3)
-
319 (87.9)
Nitrofurantoin
-
323(88.5)
-
20 (5.5)
-
22 (6.0)
Mortality
30 day mortality (all causes) = 9.7%
Irish Data (paper in production)
Survival
Treatment by Class
• Penicillins
Useless
• Cephalosporins
Useless
• Penicillins +B-lactamase
inhibitor
Unreliable
• Quinolones
If sensitive
• Aminoglycosides
If sensitive
• Carbapenems
Most reliable...for now
Carbapenems
• E.g. Meropenem, 1st line choice for
treatment of serious ESBL infections
• stability to all the currently recognised,
frequently occurring ESBLs
• extensive clinical experience
• Ertapenem also useful for UTIs, home IV tx
(once daily)
• Excess carbapenem use will result in
resistance
Paterson DL and Bonomo RA. Clin Microbiol Rev 2005; 18 (4): 657-686
A glimpse of the future...
Other antibiotics
• Nitrofurantoin po– outpatient setting
• Tigecycline IV– with caution in E coli and
Klebsiella (Pseudomonas and Proteus
inherently resistant)
• Fosfomycin, Temocillin, Pivmecillinam
• Trimethoprim, Aminoglycosides, Quinolones
when susceptible
Paterson DL and Bonomo RA. Clin Microbiol Rev 2005; 18 (4): 657-686
Vancomycin and Gentamicin Dosing
• Vancomycin and Gentamicin are nephrotoxic
and ototoxic
• Important not to overdose in this age group
• Elderly often have some degree of renal
impairment
• Assess renal function by urea and creatinine
levels
• If normal, treat normally but watch levels after
24 h of treatment
• If levels high will have to reduce dose