Exam #1: Infectious Disease Flashcards
What is the difference between morbidity & mortality?
Morbidity= Illness Mortality= Death
What is immune senescence?
Decline in immune response with age
What are the main features of immune senescence?
1) Depressed T-cell response & depressed T-cell macrophage interaction
2) Decreased B-cell affinity
How do co-morbid diseases complicate infections?
Physiologic “frailty” predisposes to worse infections & damped immune response
What is the impact of nutritional status on immune function?
Malnutrition impairs immune function
What are the long-term care considerations for infectious diseases?
1) Residence in LTC facility puts older adult at risk
2) Widespread ABX use increased likelihood of resistant infection
3) Resistance in impaired by factors of age & residency
4) Maintaining UTD immunizations is critical
How is fever redefined in nursing-home residents?
- Temp. >2 F of baseline
- Oral temp. >99
- Recatal temp. >99.5
*****Note that fever may be absent in 30-50% of older frail adults w/ serious infections
What is the most common cause of iatrogenesis in the elderly?
Medication management
How are antibiotics dosed in the elderly population?
Renal function
*****Also, note that there are many antibiotic interactions with commonly prescribed medications for older adults
What is the minimum criteria for ABX initiation for UTI without catheter?
- Fever AND one of the following:
1) New or worsening urgency
2) Frequency
3) Suprapubic pain
4) Gross hematuria
5) CVA tenderness
6) Incontinence
What is the minimum criteria for ABX initiation for UTI with catheter?
Fever OR one of the following:
1) New CVA tenderness
2) Rigors
3) New-onset delerium
What is the minimum criteria for ABX initiation for skin & soft tissue infection?
Fever OR one of the following:
1) Redness
2) Tenderness
3) Warmth
4) New or increasing swelling of affected site
What is the minimum criteria for ABX initiation for respiratory infection?
- Fever > 102 AND RR >25, or productive cough
- Fever >100 but 25 + Pulse >100
- Afebrile w/ COPD AND new or increased cough w/ purulent sputum
- New or increased cough AND RR> 25 or new-onset delerium
What is the minimum criteria for ABX initiation for fever without source of infection?
New-onset delirium or rigors (chills)
**Note that the patient should be fully underessed to look for a source of infection first
What is the most common cause of bacterial pneumonia in older adults?
Streptococcus pneumoniae
What is the first line antibiotic therapy for community acquired pneumonia?
- Beta-lactam/ Beta-lactamase combination (PCN or cephalosporin)
given with or without macrolide - OR newer fluoroquinolones with enhanced activity against S. pneumoniae
What is the first line antibiotic therapy for hospital acquired pneumonia?
Generally, initial regimens should be broadly inclusive & then narrow
- IF MRSA is suspected–vancomycin or linezolid
How can the risk of penumonia reduced?
1) Immunization
2) Smoking cessation
3) Aggressive treatment of comorbidities
4) System changes in the LTC facility
What is the recommendation for flu vaccination in the geriatric population?
Annual flu vaccination recommended for ALL adults
How does UTI in geriatrics differ from young adults?
Geriatric= resistant isolates e.g. Pseudomonas aeruginosa
Is treatment recommended for asymptomatic bacteruria?
No
What antibiotics are recommended for Lower UTI in women?
Fluoroquinolones (vs. bactrim)
**Only culture if first round therapy is ineffective
How does management of Upper UTI differ from lower UIT?
Much more serious
- IV abx
- Longer course of therapy
- More constitutional symptoms d
What is the most common cause of UTI in older men?
Prostatic Disease
How does treatment of UTI differ in men & women?
Longer treatment course in men: ~14 days
What is the most common cause of TB in older adults?
Reactivation
What are the recommendations for a “positive” PPD?
> 15mm= universally positive
> 10mm= positive in:
- nursing home
- recent converters
- immigrants
> 5mm= positive in HIV
How is TB treated?
Isoniazid for 9 months
What is infective endocarditis? What is it associated with and now is it treated?
Infection of the endocardial surface of the heart
- Associated with degenerative valvular disorders ‘
- Treat with 4-6 weeks of abx
What is the most common cause of septic arthritis? How is it treated?
- S. aureus
- Aggressive antibiotic with serial arthrocentesis
- Surgical drainage if conservative strategy fails
What is the most common cause of osteomyelitis in old age? Why is this more common in the elderly?
- S. aureus
- Pressure ulcers that go down to the bone
When should you consider meningitis as part of your differential?
Fever + mental status change
What is the optimal treatment for neurosyphilis?
PCN G
When is Herpes Zoster vaccine recommended?
> 60 years-old
What are three infectious diseases that are associated with Bell’s Palsy?
1) Herpes Simplex
2) Varicella zoster (shingles)
3) Lymes
When should you get a surgical consult on an elderly patient with abdominal pain?
Abdomianl pain + fever= surgical consult
What are the fist line treatments for C.diff?
- Metronidazole for mild to moderate cases
- Vancomycin
