infections in geriatrics, 2006
TRANSCRIPT
Infections in Geriatrics, 2013
Jerome M. Larkin, M.D.
Slides courtesy of:Staci A. Fischer, M.D., FACP
Division of Infectious Diseases
The Warren Alpert Medical School of Brown University
Outline • Epidemiology of infections in the elderly
• Immune senescence
• Fever of unknown origin
• Pneumonia
• UTI
• Skin and soft tissue infection
• Bloodstream infection, endocarditis
• C. difficile in the elderly
• Antibiotics in the elderly
• Infection prevention
Who is old?
• Young Old: 65-75
• Middle Old: 75-85
• Old Old: >85
• 15% of new HIV infections in those >50 years
Clinical Practice Guideline for the Evaluation of Fever and Infection in Older Adult Residents of Long-Term
Care Facilities
High KP, Bradley SF, Gravenstein S, et al, CID 2009:48, 149
IDSociety.org
Infections in the Elderly: Trends
• By 2030, 20% of the US population will be over the age of 65 (69 million)
• 1990-2002 (Arch Intern Med 2005;165:2514-20)
– 21.4 million hospitalizations; DRG data
– 48% had an infection as primary Dx
– Infection related hospitalizations increased 13% over that time period
– Highest rates of hospitalization for infection were in those > 85 years
Infections in the Elderly: Trends
• 22% increase in rate of hospitalization for septicemia
• Rates for LRTI, UTI, intraabdominal infections were stable
• Increases: endocarditis (240%), prosthetic device-related infxn (130%), postoperative infections (80%)
• 1/3 of deaths >65yrs attributed to infxn
Infections in the Elderly: Trends
• 46% of infection hospitalizations were for lower respiratory tract infections – 48% of infection-related hospital deaths
• 16% urinary tract infections – 70% women
– 6% of infection-related hospital deaths
• 12% septicemia – 34% of infection-related hospital deaths
Immunosenescence in the elderly
• NK cell function impaired; increased #s
• PMN migration is random, delayed
• Phagocytosis intact (DM, chronic bronchitis are exceptions)
• Increased sensitivity to cytokines that induce apoptosis
• Decreased peroxide and nitric oxide production, IL-2, CD8, TLR’s, Ig production/naïve B-cells
• Impaired wound healing
• Impaired response to vaccinination
Clin Infect Dis 2000;31:578-85.
Aging and infection
• 3-fold increase in prevalence of CAP
• 20-fold increase in prevalence of UTI
• Increased risk of infection per day of hospitalization
• Greater diversity of pathogens than in younger adults – Listeria
– Tuberculosis
– Legionella
– Pneumococcus
Lancet Infect Dis 2002;2:659-66
Aging and infection
• Altered barriers to infection: GI, Resp tracts, skin
• Increase in communal living/daycare leads to exposure to circulating pathogens, resistant organisms
• Immune fxn impaired by increased number of co-morbidities
• Chronic conditions exacerbated by infections
Aging and infection: Challenges
• Clinical presentation differs markedly
– Fewer symptoms
– Fever absent or blunted in 20-30% severe infections
– Nonspecific symptoms (delirium, anorexia, weakness, etc.)
• Yield of diagnostic tests may be lower
• Cognitive impairment decreases ability to relate symptoms, compliance with tx
Lancet Infect Dis 2002;2:659-66
Signs of Potential Infection
• Fever
• New or increasing confusion
• Incontinence
• Falling
• Deteriorating mobility
• Decreased appetite/fluid intake
• Failure to cooperate with staff
Fever in the Elderly
• 1/3 of patients with acute infection have no fever
• Lower baseline temperatures (36.7°C vs. 37.3°C)
• Onset of fever delayed several hours
• Best method of measurement: rectal>TM>oral
• Any acute change in functional status should raise suspicion of infection
Definition of fever in the elderly*:
• Increase in baseline temperature by > 1.1°C (2oF) or
• Single measurement over 37.8°C (100°F) or
• Two measurements over 37.2 °C (99°F)
*Healthy elders in the community can probably be
approached more conventionally
Fever of Unknown Origin in the Elderly
• Elderly: etiology determined in 87-95%
• 35% infection – 10% tuberculosis, 12% intraabdominal abscess,
7% endocarditis*, 6% other
• 30% connective tissue diseases temporal arteritis polymyalgia rheumatica rheumatoid arthritis
• 20% malignancy (lymphoma, hepatic mets)
• 8% DVT, drug fever, hyperthyroidism
*increased PV, AS valve dz, devices, interventions, S. aureus
Urinary Tract Infections in the Elderly
• Asymptomatic bacteriuria increases with age (1 in 10 men, 1 in 5 women) – Treatment rapid relapse
– Higher incidence of antibiotic toxicity in the elderly (more rapid absorption, drug interactions, etc.)
– Urinary tract abnormalities (cystocoele, rectocoele, urethral strictures, etc.)
– Chronic catheterization (100% with bacteriuria and WBC’s)
– If no symptoms and no pyuria . . . NO NEED TO TREAT
��UTI in the Elderly: DX
• Catheter: one of the following-
– Fever
– New onset CVA tenderness
– New onset delerium
– Rigors
UTI in the Elderly: DX
• No Catheter: Acute Dysuria or Fever and one of the following-
– New or worsening urgency
– Frequency
– Suprapubic pain
– Gross hematuria
– CVA tenderness
– Incontinence
UTI in the elderly
• Ambulatory patients: E. coli
• Nursing Home residents: Enterococcus, Klebsiella, Proteus, Pseudomonas
• Indwelling catheters: Providencia – > 10 wbc’s is significant
– If MRSA, VRE, Candida – remove or change the catheter (biofilms)
• Staph aureus: think endocarditis
UTIs in the elderly: Treatment
• Culture is critical in this population
• 3-5 days in women without catheters(?)
• 14 days in men or catheterized women
• Candida: Change the catheter!!!
• Relapses are common – repeat U/A, culture one week after antibiotics discontinued
• Remember that pyuria is the key to Dx
Pneumonia in the elderly
• >900,000 cases of community-acquired pneumonia in adults > 65 yrs annually
• 1 in 20 people above the age of 85 has pneumonia each year
• Risk factors: COPD, CHF, DM, malnutrition, swallowing disorders, alcoholism
• Smoking increased risk of pneumococcus
• Highest risk for related bacteremia among infxns in the elderly
Clin Infect Dis 2004;39:1642-50
Pneumonia in the Elderly
• Frequency of bacterial pneumonia increases with age
• Atypical presentation delayed treatment increased mortality
• Cough, pleuritic chest pain, fever often absent
• Altered mental status is the most common symptom
Pneumonia in the elderly
• Silent microaspiration of oropharyngeal secretions – Sleep indium-111 gauze study (Kikuchi, 1994): 71%
with CAP aspirated, 10% age-matched controls
– Feeding tubes may actually increase the risk of pneumonia and death in those who aspirate
• Mortality: bedridden before pneumonia, hypothermia, creatinine > 1.3, swallowing disorder
• Recovery can be prolonged (months) – Hospitalization, immobility
Pneumonia in the elderly: DX
• Tachypnea (>25)
• Hypoxia
• New infiltrate
• Purulent sputum
Pneumonia in the Elderly
• Viral: influenza, RSV
• Bacterial: Pneumococcus GNRs (E. coli, Klebsiella) Haemophilus influenzae Staph aureus Legionella pneumophila
• Empiric treatment: broad spectrum vs guided by culture
• NHR: increasing resistance (ESBL’s)
Pneumonia in Elderly: Pathogens
• Viral: influenza, RSV, Human Metapneumovvirus
• Bacterial: Pneumonococcus, GNR’s (Klebsiella, Haemophilus), Moraxhella, S. aureus*
• Atypical: Legionella, Chlamydia
• TB *post influenza
Antibiotic resistance in LTCFs
• MRSA
• VRE
• ESBLs
• Candida resistance
• Antibiotic overuse, crowding, infection control, indwelling catheters, microaspiration, frequent hospitalizations
Tuberculosis
• Nursing home outbreaks
• Two-step PPD testing in all elderly
• Symptoms atypical
• Disseminated infection more common
• +PPD: isoniazid tolerate AST, ALT < 500 U/L
Skin and soft tissue infections
• Cellulitis: MRSA, group A Strep (outbreaks in nursing homes), slow to resolve
• Herpes zoster
• Pressure sores (polymicrobial) – Rule out underlying osteomyelitis
– Surface cultures unreliable
– Bone biopsy cultures are best
• Scabies/Lice:
– suspect if >1 unexplained rash
– often detected when staff develop symptoms
• Conjunctivitis:
– respiratory bacteria (culture helpful), adenovirus
• Candida
– can be resistant species if not responding to typical rx
Bloodstream Infections
• Urinary tract, respiratory tract, skin, intraabdominal infections, IV catheters associated with ~6% 2ndary bacteremia
• GNR’s more likely as pathogens due to GI/GU source
• May result in vertebral osteomyelitis, hematogenous spread to femur, tibia, humerus (present months later with pain)
Bloodstream Infections
• 5-40 episodes/100,000 patient days
• Associated with high mortality (11- 50%)
• Death often seen in first 72 hours
• Mortality highest with associated pneumonia
• Elderly at relatively high risk of having contaminants isolated from BCx’s due to difficulty of phlebotomy
Endocarditis in the Elderly
• Men > women; mitral > aortic
• Staphylococci
• Streptococci [Strep bovis (colon CA)]
• Enterococci
• Lethargy, malaise, fatigue, anorexia, weight loss
• Back pain, arthralgias, stroke syndrome
• Microscopic hematuria, proteinuria
• TTE: less specific in the elderly
Prosthetic Device Infections
• Prevalence of Prosthetic Joints, Pacemakers, Fixation Hardware, Vascular Grafts all increase with age
• Are permissive to infection due to formation of biofilms
• Typically infections due to Staphylococci, Streptococci
• Treatment typically requires removal with prolongs abx courses with bactereicidal agents
• Goal of treatment should be maintenance of functional status>>>curative vs suppressive treatment
C. Difficile colitis in the elderly
• Antibiotic use (bacitracin for VRE colonization, UTIs/bacteriuria)
• Outbreaks in LTCFs
• May not present with diarrhea, but with abdominal distension and mental status changes
• Toxic megacolon more common
• Mortality increasing in the elderly
• Spores not destroyed by etoh gels
Antibiotics in the elderly
• Altered absorption, distribution, metabolism interactions
• More toxicity – Levofloxacin: CNS toxicity, delerium
– Gatifloxacin, gemifloxacin: hypoglycemia
– Linezolid: hematologic toxicity, interaction with SSRIs (MAOI)
– Aminoglycosides: renal toxicity, vestibular toxicity
– INH, rifampin: hepatotoxicity
– Carbapenems: tremor, seizures
– Telithromycin: hepatotoxicity
Antibiotics in the elderly:
• 40% of those over 70 have GFR<60
• Achlorhydria, gastroparesis, H2 blockers, PPI’s, antacids may alter absorption
• Net interactions may be difficult to predict: rifampin, bactrim, warfarin, quinolones, beta-blockers, statins, dig
• Cost may decrease compliance
12 month observational study of abx use in Canadian nsg homes: 22 facilities, 2400 patients, 9300 courses of abx
• 8-17% on abx at any one time
• 50-70% treated in the past year
• 22-89% of treatment courses inappropriate
Loeb M, et al; J Gen Intern Med 2001; 16:376
Infection Prevention in the Elderly
• Vaccinations: influenza, pneumococcus (q5-6 years; 23-valent), Tdap x1 then Td q 10 yrs, zoster
• Avoid indwelling lines, catheters
• Nutritional support
– MVI, zinc, selenium
– Watch vitamin A: decreased CD3 and CD4 cells?
– Vitamin E?
– Protein: up to 1.2 g/kgday improves wound healing, muscle mass/mobility
Questions???