OutpatientAbxTalk4-2.. - NP/PA/CNM Professional Practice Group
Download
Report
Transcript OutpatientAbxTalk4-2.. - NP/PA/CNM Professional Practice Group
In the Clinic: Evidence Based
Management of Infections
Daniel Deck, Pharm.D.
San Francisco General Hospital
Overview
Community-acquired pneumonia
Upper respiratory tract infections
Urinary tract infections
Skin and Soft-tissue infections
Community-acquired pneumonia
Community Acquired Pneumonia
(CAP): definition
At least 2 new symptoms
Fever or hypothermia
Cough
Rigors and/or diaphoresis
Chest pain
Sputum production or color change
Dyspnea
New infiltrate on chest x-ray and/or
abnormal chest exam
No hospitalization or other nursing
facility prior to symptom onset
Diagnosis
Chest radiograph – needed in all cases?
Avoid over-treatment with antibiotics
Differentiate from other conditions
Specific etiology, e.g. tuberculosis
Co-existing conditions, such as lung mass or pleural
effusion
Evaluate severity, e.g. multilobar
Unfortunately, chest physical exam not sensitive or
specific and significant variation between
observers
Arch Intern Med 1999;159:1082-7
Microbiological Investigation
Sputum Gram stain and culture
Remains somewhat controversial
30-40% patients cannot produce adequate sample
Most helpful if single organism in large numbers
Usually unnecessary in outpatients
Culture (if adequate specimen < 10 squamous
cells/LPF; > 25 PMNs/LPF): antibiotic sensitivities
Limited utility after antibiotics for most common
organisms
Etiology
Clinical syndrome and CXR not reliably predictive
Streptococcus pneumoniae 20-60%
Haemophilus influenzae 3-10%
Mycoplasma pneumoniae up to 10%
Chlamydophila pneumoniae up to 10%
Legionella up to 10%
Enteric Gram negative rods up to 10%
Staphylococcus aureus up to 10%
Viruses up to 10%
No etiologic agent 20-70%
“Atypicals”
S. pneumoniae
2/3 of CAP cases where etiology known
2/3 lethal pneumonia
2/3 bacteremic pneumonia
Apx. 20% of cases with pneumococcal pneumonia are
bacteremic (variable)
Risk factors include
Extremes of age
Alcoholism
COPD and/or smoking
Nursing home residence
Influenza
Injection drug use
Airway obstruction
*HIV infection
S. pneumoniae – drug resistance
~ 25-35% penicillin non-susceptible by old
standard nationwide, but most < 2 mg/mL
Using the new breakpoints for patients without
meningitis, 93% would be considered
susceptible to IV penicillin
Other beta-lactams are more active than
pencillin, especially
Ceftriaxone, cefotaxime, cefepime,
amoxicillin, amoxicillin-clavulanate
S. pneumoniae – drug resistance
Other drug resistance more common with increasing
penicillin minimum inhibitory concentration (MIC)
Macrolides and doxycycline more reliable for PCN
susceptible pneumococcus, less for penicillin nonsusceptible
Trimethoprim-sulfamethoxazole not reliable
Fluoroquinolones – most S. pneumoniae are
susceptible
Clinical failures have been reported
No resistance with vancomycin, linezolid
Risk Factors for Drug-Resistant
Pneumococcal Pneumonia
Age < 2 year or > 65 years
-lactam antibiotics within 3 months
Alcoholism
Immunocompromised patients
Multiple comorbidities
Exposure to children in day care centers
Conditions that Increase the
Morbidity/Mortality of CAP
COPD
CHF
Alcoholism
CAD
Leukopenia
Malignancy
Bacteremia
Neurologic disease
Diabetes mellitus
Chronic liver disease
Renal insufficiency
Immunosuppression
IDSA Outpatient Empiric Therapy
Recommendations
Previously Healthy & NO
DRSP Risk Factors
DRSP Risk Factors or High Level
Macrolide Resistance > 25%
Macrolide (e.g azithromycin)
or
Doxycycline
1) Fluoroquinolone* or
2) a β-Lactam# plus
a Macrolide or Doxycycline
*moxifloxacin, gemifloxacin, or levofloxacin (750mg)
1 gm PO tid or Augmentin® XR 2 gm PO bid are preferred. Ceftriaxone,
cefpodoxime proxetil, and cefuroxime axetil 500 mg PO bid are alternatives
#Amoxicillin
We love doxycycline
Adult inpatients June 2005 – December 2010
Compared those who received ceftriaxone +
doxycycline to those who received ceftriaxone alone
2734 hospitalizations: 1668 no doxy, 1066 with doxy
Outcome: CDI within 30 days of doxycycline receipt
CDI incidence 8.11 / 10,000 patient days in those
receiving ceftriaxone alone; 1.67 / 10,000 patient days
in those who received ceftriaxone and doxycycline
Doernberg et al, Clin Infect Dis 2012;55:615-20
Duration of Therapy
5 days should be the minimum duration of
therapy
Patients should be afebrile for 48-72 hours
No more than 1 CAP-associate sign of clinical
instability (T > 37.8ºC, HR >100, RR > 24, SBP
< 90, O2 sat < 90%,
pO2 < 60)
Short-Course Therapy
Defined as less than 7 days of therapy
Short course therapy may reduce side effects,
cost, and resistance
Azithromycin has been used for 3-5 days
Ceftriaxone, amoxicillin, and fluoroquinolones
have been used for 5 days
Reasons for Inadequate
Response to Empiric Therapy
Inadequate Antibiotic Selection
Unusual Pathogens
Complications of Pneumonia
Incorrect Diagnosis
Drug-resistant organisms
Upper Respiratory Tract
Infections
Upper respiratory tract infections
Rhinosinusitis
~13 million outpatient visits per year
Viral causes >>>> bacterial
Minimal to NO benefit from antibiotics given for
short duration of disease
Xray/CT not helpful in distinguishing cause
Rhinosinusitis diagnosis
Major Criteria
Minor Criteria
Purulent anterior nasal discharge
Headache
Purulent posterior nasal discharge
Ear pain, pressure, or fullness
Nasal congestion or obstruction
Halitosis
Facial congestion or fullness
Dental pain
Facial pain or pressure
Cough
Hyposomia or anosmia
Fever (chronic disease)
Fever (acute disease)
Fatigue
Need at least 2 major or 1 major and ≥ 2 minor criteria
IDSA guidelines: rhinosinusitis
Antibiotics may be helpful if….
1. Persistent signs/symptoms > 10 days
2. Severe symptoms
Fever > 39C
Purulent nasal drainage for 3 consecutive days
Facial pain
3. Biphasic illness
IDSA guidelines: rhinosinusitis
Recommened
st line therapy =
1
Amoxicillin/clavulante
(standard dose)
Consider high dose (XR
formulation) with severe
disease, elderly, recent
antibiotic use or hospitalization
Alternatives: doxycycline,
levofloxacin
Treatment duration: 5-7 days
Not Recommended
• Macrolides
• TMP/SMX
• Oral cephalosporins
• Routine MRSA coverage
IDSA guidelines: rhinosinusitis
DO
Antibiotic duration 5-7 days
DO NOT
Decongestants
Nasal saline irrigation
Antihistamines
Intranasal corticosteroids
NP swab
Consider changing abx if
Clinically worse at 48-72 hours
No improvement at 3-5 days
GAS pharyngitis
Accounts for 15% of adult sore throat visits
Dx: culture or rapid antigen test
Tx :
1st line = PCN or amoxicillin x 10 days
Mild PCN allergy = cephalexin x 10 days
Alternatives = clindamycin or clarithromycin x 10
days OR azithromycin x 5 days
Antibiotic allergies: History is key!
Past reaction
Source
Current reaction
Timeline: symptoms & meds
Timeline: symptoms & meds
Labs, histology
Detailed description
Concurrent illness
Treatment
Concurrent illness
Workup
Other exposure
Algorithm for the use of cephalosporins in patients with
reported penicillin allergy
Practical management of antibiotic allergy in adults. McLean-Tooke et al, J Clin
Pathol 2011;64:192-199
Acute bronchitis
10 million healthcare visits annually
80% of patient prescribed antibiotics
95% of case have a viral etiology
Antibiotics = No clinical benefit plus increased
cost, adverse reactions, increased antibiotics
resistance
Skin and Soft Tissue Infections
Skin Infection Anatomy
Epidermis
Impetigo
Erysipelas
Dermis
Subcut. Fat
Fascia
Muscle
Cellulitis
Abscess,
furuncle,
carbuncle
Fasciitis
Pyomyositis
S. pyogenes Resistance in the
U.S. 2002-2003
Antimicrobial Agent
Percent Resistant*
Penicillin
0.0%
Cefdinir
0.0%
Clindamycin
0.5%
Erythromycin
6.8%
Azithromycin
6.9%
Clarithromycin
6.6%
Levofloxacin
*Richter SS. Clinical Infectious Diseases 2005; 41:599–608
0.05%
S. aureus Susceptibilities from
Outpatient Wound Isolates
Antimicrobial Agent
Percent Susceptible*
Oxacillin
52.0%
Trimethoprim-Sulfamethoxazole
99.6%
Clindamycin
86.7%
Erythromycin
41.5%
Tetracycline
93.8%
Vancomycin
100%
*http://ww2.cdph.ca.gov/PROGRAMS/MDL/Pages/CaliforniaAntibiogramProject.aspx
Risk Factors for CA-MRSA
Prior history of MRSA infection
Close contact with person with similar infection
Recent antibiotic use
Reported “spider bite”
Outbreaks in IVDU, prisoners, athletes, children,
Native Americans
Cellulitis vs Abscess
Cellulitis
Abscess
Pathogen
Beta-hemolytic streptococci
Staph aureus (CA-MRSA)
Treatment
Antibiotics
Incision and Drainage
+/- ABX
Antibiotics
Duration
•
•
•
•
Penicillin (amoxicillin)
Cephalosporins (cephalexin)
Clindamycin (PCN allergic)
TMP/SMX???
5-10 days; monitor clinical
response
•
•
•
•
TMP/SMX
Doxycycline
Clindamycin
Linezolid $$$
Abscess: when to prescribe abx?
Antibiotics may be warranted if
Abscess is large (> 5 cm) or incompletely drained
Significant surrounding cellulitis
Systemic signs and symptoms of infection are present
Patient is immunocompromised
Difficult to drain area (face, hand, genitalia)
Extremes of age
Animal & Human Bite Wounds
One half of all Americans bitten in their lifetime
80% of wounds are minor, 20% require medical care
Human and cat bites frequently become infected so
always require treatment even if not grossly infected
Only 5% of dog bites get infected so treatment
indicated if bite is severe, grossly infected, or
significant comorbidity (e.g. diabetes)
Bite Wound Treatment
Wound cleaning, irrigation and debridement!
Antibiotics directed against skin flora of patient and
oral flora of biting animal/human
Humans (viridans strep, Eikenella, mixed anaerobes)
Dogs (Pasteurella, Capnocytophaga, anaerobes)
Cats (Pasteurella, anaerobes)
Antibiotic Regimens
Oral
Urinary Tract Infections
Increasing resistance in urinary pathogens
E.coli accounts for ~95% of all cases
TMP/SMX resistance in E.coli > 20% in many parts of the United
States
Resultant shift to use of quinolones as first-line empirical therapy
over the past 10-20 years
Quinolones have been associated with “collateral damage”
Increased rates of MRSA
Selection for resistant GNRs including ESBL- producers
Clostridium difficile-associated diarrhea
When to get a culture?
Suspect multidrug-resistant organism
Recent abx
Prior infection or colonization
Recent travel
Suspect pyelonephritis
Follow up cultures unnecessary in patients whose
symptoms resolve
2010 IDSA recommended treatment
regimens for uncomplicated cystitis
First Line Regimens
Nitrofurantoin macrocrystals
(Macrobid®) 100 mg BID X 5 days
(avoid if early pyelo suspected)
Trimethoprim-sulfamethoxazole
1DS tablet BID X3 days
(avoid if resistance prevalence
exceeds 20% or if used for a UTI in
previous 3 months)
Fosfomycin trometamol
3 grams x 1 dose
(lower efficacy than some other
agents, avoid if early pyelo suspected)
Gupta K et al. Clin Infect Dis. 2011;52(5):103-20.
Second Line Regimens
Ciprofloxacin 500 mg BID x 3 days
(resistance prevalence high in some
areas)
Oral β-lactams (including
amoxicillin/clavulante, cefdinir,
cefaclor, cefpodoxime, cephalexin
(less data); avoid ampicillin or
amoxicillin alone; lower efficacy than
other available agents, treat for 3 to 7
days)
What is fosfomycin?
Phosphonic acid derivative that inhibits cell wall synthesis
Activity against many gram positive and gram negative
organisms
In U.S., only oral salt available as a powder sachet
dissolved in water
High concentration in the urine
Usual dose 3g x 1 (single dose)
Can also consider 3g every other day x 3 doses or 3g q
72 hrs. x 14 days
3g packet costs about $50
Treatment of cystitis: Back to the future
Nitrofurantoin (Macrobid®)
PROS
Fosfomycin trometamol
PROS
As effective as TMP/SMX
Clinical efficacy similar to TMP/SMX
Minimal drug resistance
Low propensity for collateral damage
Low propensity for collateral damage
Single dose therapy
CONS
Blood levels not sufficient to treat early
pyelonephritis
Avoid in pts with CrCl < 50 ml/min
Nausea, headache (similar adverse
effect rate as TMP/SMX)
Rare pulmonary hypersensitivity
CONS
Microbiologic efficacy lower than
TMP/SMX and nitrofurantoin
Not sufficient to treat early pyelo
Susceptibility testing not routinely
performed
Diarrhea, nausea, headache (similar
adverse effect rate as nitrofurantoin)
Other oral options for cystitis due to
resistant organisms
Amoxicillin-clavulanate (susceptible
ESBL-producing E. coli)
Nitrofurantoin
Fosfomycin references:
Falagas et al, Lancet Infect Dis 2010;10:43-50
Neuner et al, Antmicro Agents Chemother 2012;56:5744-48
Asymptomatic Bacteriuria
Do not screen if no symptoms are present
Except in pregnancy
Other special situations
Do not prescribe antibiotics!
Relative Risk ~3x for recurrence of symptomatic bacteriuria
when asymptomatic patients receive antibiotics
Final Questions?
Contact Info
Extension: 415-206-5574
Email: [email protected]
SFGH “As real as it gets”