microbes/coverage/infections Flashcards
What is pseudomonas
Gram -ve aerobic bacilli
What PO abx cover pseudomonas
Ciprofloxacin and levofloxacin
What IV abx do we most commonly use to cover pseudomonas
Pip-Taz, Cefepime, Ceftazidime, Gentamycin (in addition to Beta lactam for severe infection)
Bacteria causing UTI
“KEEPS”
Klebsiella
enterococcus faecalis/enterobacter cloacae
e.coli
proteus mirabilis/pseudomona aeroginosa
staphylococcus saprophyticcus/serratia marcescens
Treatment of CAP
macrolide (eg azithromycin/clarithromycin/erythromycin) or doxycycline or amox/clav
CAP treatment in pt with comorbidities
fluoroquinolone (levofloxacin)
or beta lactam (amox/clav or high dose amoxil) + macrolide (azithromycin)
CAP treatment for ICU pt
β-lactam (eg ceftriaxone 1g IV q 24, cefotaxime) + azithromycin
or fluoroquinolone (levofloxacin 750mg IV q 24) ± vancomycin 1g IV q 12
Or ceftriaxone + levo
what is the rash of lyme dz
erythema migrans : spreading bulls eey erthema usually at site of bite (but not always)
list 4 systemic complications of Lyme dz
carditis, heart block meningitis, encephalitis, sz, CN palsy arthritis, pain syndromes ophthalmologic (keratitis, conjunctivitis, retinal detachment) hematologic (adenopathy, splenomegaly)
what is the treatment for Lyme dz
doxycycline
List factors that would increase benefit of treating for Lyme dz
> 36hr of contact
early presentation
what are the bacterial agents in infective endocarditis?
HACEK group Haemophilus actinobacillus cardiobacterim hominis ekinella kingella kingae
S. aureus
strep viridans
strep bovis
enterococcus
List noninfectious inflammatory lung processes in the differential for pneumonia.
- Mineral dusts (e.g. silicosis)
- Chemical fumes (e.g. chlorine, ammonia)
- Toxic drugs (e.g. bleomycin)
- Immunologic diseases
o Sarcoidosis
o Goodpasture’s
o Collagen vascular disease - Hypersensitivity to environmental agents (e.g. farmer’s lung)
- Tumours (including post-obstructive infections, adenopathy, and lymphangitic spread)
When we say “typical” and “atypical pneumonia” what etiologies are being implied?
- Typical:
o Streptococcus pneumonia
o Haemophilus influenzae
- Atypical: o Mycoplasma o Chlamydia o Viral Legionella
List 5 risk factors for S. pneumoniae pneumonia. (
- DM
- Cardiovascular disease
- Alcoholism
- Sickle cell disease
- Splenectomy
- Malignancy
Immunosuppression
What is the presentation of “Legionnaires disease”?
- Severe systemic illness
- Associated malaise, lethargy, high fever
- Dry cough (late purulent sputum)
- Pleuric chest pain
- Prominent GI symptoms (diarrhea and abdominal cramps)
When are antibiotics indicated for aspiration?
- Patient develops signs of bacterial pneumonia
o New fever
o Expanding infiltrate > 36 hours after aspiration
Unexplained deterioration
What lab value when elevated should increase the suspicion of PJP pneumonia?
- LDH… although this is not specific and VERY debatable
List treatment options for PJP pneumonia.
- Trimethoprim-sulfamethoxasole (1st line)
o 20 mg/kg of TMP and 100mg/kg SMX/day dived QID - Pentamidine 4mg/kg over 1 hour
Clindamycin 900mg TID
How is Hantavirus acquired?
- Inhalation of aerosolized rodent urine and feces
What is the treatment for infective endocarditis
Native valve or prosthetic valve: vancomycin 15mg/kg q 12 plus gentamycin 1mg/kg q8
native valve plus IVDU: vanco alone
What is appropriate antibiotic therapy for Ludwig’s Angina (Stanford)?
- Penicillin 12 million Unit/day or more divided Q4h + flagyl 1g then 500mg q6h
- Clinda 600-900 IV q8h
- Piptazo
Ceftriaxone
List 10 risk factors for developing MRSA:
- Immunocompromised (people living with HIV/AIDS, cancer patients, transplant recipients, severe asthmatics, kidney disease, alcoholics, cirrhosis…)
- Diabetics
- Intravenous drug users
- Homeless populations
- MSM
- Jail detainess
- Daycare
- First Nation
- Gym use, sports teams
- Soldiers
- Low SES associated with crowded living quarters
- Use of quinolone antibiotics
- Young children
- The elderly
- College students living in dormitories
- Persons staying or working in a health care facility for an extended period of time
What are 6 antibiotics with activity against MRSA?
- TMP/SMX 1xDS bid
- Clindamycin 150-450mg PO q 6hr or 600-900 mg IV q 8
- Doxycycline 100mg PO bid
- Linezolid 600mg PO/IV q 12
- Vanco: 15mg/kg IV q 12
- Rifampin 300mg PO bid (combine with TMP/SMX as rapid resistance develops)
List types of diphtheria.
Respiratory - Facial (pharyngeal or tonsillar) - Nasal Laryngeal (trachobronchial) Cutaneous - Primary skin infection - Secondary infection of preexisting wound
List systemic features of diphtheria.
- Nervous system o Muscle weakness (proximal first affected) o Polyneuritis o Neuropathy (in > 25%, starts in head w/ CN, palate muscle paralysis) - Cardiac o Myocarditis o CHF o ECG /ST changes o Conduction disturbances - Kidneys
List management steps in diphtheria.
- Respiratory isolation
- Protect the airway
- Limit effects of already produced toxin
o Equine serum diphtheria antitoxin - Eliminate future toxin (terminate the growth of C. diphtheriae)
o Antibiotics (Erythromycin > penicillin, clarithromycin, azithromycin - Active immunization
Describe the three phases of pertussis.
- Catarrhal phase
- After 7 – 10 day incubation
- Duration 2 weeks (indistinguishable from URTI) - Paroxysmal phase
2 – 4 weeks - Convalescent phase
Weeks to months
List major complications of pertussis.
- Superinfections i.e. pneumonia
- Aspiration of gastric contents and respiratory secretions
- CNS complications: seizures, encephalopathy, ICH
- Cardiac: Bradycardia, hypotension and cardiac arrest in young infants
- Respiratory: Severe pulmonary hypertension in young infants
Metabolic: Hypoglycemia (esp young infants)
What is the antibiotic of choice for the treatment of pertussis?
erythromycin 40-50mg/kg/d bid-tid x 14 d
For how long are patients with pertussis considered infectious?
- 3 weeks after initiation of paroxysmal phase or 5 days after initiation of antibiotics (strict droplet isolation)
What toxin must be considered in the differential for tetanus?
strychanine
What causes the clinical manifestations of tetanus?
- Neurotoxin tetanospasmin (TS)
List 4 types of tetanus
- generalised
- localised
- cephalic
- neonatal
What characterizes cephalic tetanus?
- Cranial nerve palsies (i.e. CN VII) – May precede muscle spasms
List a differential for tetanus
- acute abdo
- black widow spider bite
- dental abscess
- dislocated mandible
- dystonic reaction
- encephalitis
- head trauma
- hyperventilation
- hypocalcemia
- meningitis
- peritonsilar abscess
- stiff-man syndrome
- psychogenic
- rabies
- sepsis
- status epilepticus
- strychanine poisoning
- SAH
- TMJ syndrome
What are complications of tetanus
- rhabdo
- ventilatory failure
- autonomic dysfunction
- vertebral fracture
- long bone fracture
- hyperthermia
List steps in the mgmt of tetanus
Control muscle spasms:
- BZD
- propofol
- dantrolene
- MgSO4
- paralysis (don’t use succ)
Control autonomic instability
- labetalol or prpopranolol
- spinal anesthesia/intrathecal baclofen
- temporary pacing
Elimination of unbound TS
-HTIG 3000-6000U
Active immunization
Prevention of further toxin production
- wound debridement
- antibiotic
- -metronidazole 500mg PO q6
Outline tetanus prophylaxis in routine wound mgmt
3+ vaccinations: only routine boosters, no TIG
unknown or LT 3 doses:
clean wound: vaccination
high risk wound: vaccination + TIG (250U IM)
List 5 forms of botulism
Onset 18-36hrs
- Food borne
- Infant
- Wound
- unclassified
- Inadvertent/iatrogenic
What are the effects of botulism toxin?
- Blocks the release of acetylcholine from presynaptic nerve membrane, predominantly CN, autonomic nervous system, NMJ
o CN paralysis
o Descending flaccid paralysis
o Autonomic nerve dysfunction
List clinical features of botulism.
Early: weakness, malaise, lightheadedness, N/V, constipation
CNS: diplopia, blurred vision, dysphonia, dysphagia, dysarthria, vertigo, descending muscular weakness, resp muscle weakness, anticholinergic sx (dry mouth, ileus, urinary retention)
postural hypotension ptosis, EOM palsies, dilated fixed pupils absent gag weak neck muscles upper extremity GT LE weakness
decreased reflexes
normal sensory exam
How does infant botulism present?
- Constipation
- Poor feeding
- Weak cry
- Loss of head control
Hypotonia
LIST A DDX FOR BOTULISM.
Infection
- polio
- tick paralysis
- cephalic tetanus
Tumor/paraneoplastic: eaton-lambert
toxic:
anticholinergics )jimson weed, belladona), siphenhydraminem paralytic shellfish
Drugs: anticholinergic, cholinergic, Mg toxicity
Neuro: GBS +/- miller fisher variant, myesthenia gravix, dystonic rxn
Infant: sepsis, encephalitis, meningitism hypoglycemia, muscular dystrophy, degenerative CNS dx, hypothyroid
List steps in the management of botulism.
- Supportive care – ABCs, Intubation and mechaniscal ventilation PRN
- Treatment with antitoxin – Equine trivalent antitoxin
What vital capacity suggests the need for intubation?
LT 12 ml/kg or LT 30% predicted
What is the treatment of infant botulism?
Supportive +/- Human botulism immuneglobulin - BabyBIG
List risk factors for pnuemococemmia.
- Chronic respiratory or cardiac disease
- Chronic alcohol abuse
- Cirrhosis
- Diabetes
- Absent or functionally impaired spleen
- Chronic renal failure
- Nephritic syndrome
- Organ transplant
- Hodgkin’s disease
- Multiple myeloma
- AIDS
Close living conditions
List a differential for fever and rash
-meningicoccemia
-RMSF
-typhus
-typhoiid fever
-endocarditis
-vasculitis (polyarteritis nodosa, HSP, KD)
-TSS
-acute rheumatic fever
-drug reactions
-ITP
TTP
-viral exanthems
-dengue
List antibiotics for PEP to meningicoccemia
Ciprofloxacin 500mg PO x 1
ceftriaxone 125mg IM LT 12 yr or 250mg GT 12 yrs
What is the definition of TSS?
- Toxin mediated febrile illness characterized by diffuse desquamating erythroderma
- Tetrad of: High fever, hypotension, multi system organ failure, rash
- Staph: TSST-1, enterotoxin B
- GAS: pyrogenic exotoxins A and B
List 6 risk factors for TSS
- nasal packing
- tampon use
- postoperative wound infections
- post partum
- DM
- EtOh abuse
- HIV
- chronic cardiac dz
- chronic pulmonary dz
- cancer
- common bacterial infections
Provide the case definitions for Staph TSS (Box 129-6):
- Clinical Case Definition:
a. Fever: Temp > 38.9C (102F)
b. Skin Rash: diffuse macular erythema (may be mistaken for fever rash)
c. Skin Desquamation 1-2 weeks after onset
d. Hypotension: SBP 5 WBC/hpf)
v. Hepatic: bili,AST,ALT doubled
vi. Hem: platelets
Provide the case definitions for Strep TSS (Box 129-7):
- Clinical Case definition:
a. Hypotension: SBP 2 of):
i. Renal: creat >117 or >2x normal or 2x baseline
ii. Hem: plts
Provide a differential for TSS :fever and rash with hypotension
KD SSS scarlet fever Drug rxn: SJS, TEN RMSF clostridial gas gangrene leptosporiosis meningicoccemia gram -ve sepsis atypical measles viral illness
Outline the management of TSS:
- Reduce toxin production:
o Clindamycin - protein synthesis inhibition and toxin inhibition
o Give clindamycin FIRST as it decreases toxin formation and thus when you give a bactericidal agent less toxin is released
o 900mg IV q8h (40mg/kg peds) - BS Antibiotics: piptazo, vanco
IVIG: 2g/kg over several hours, then 500mg/kg/day for up to 5 days
List risk factors for severe influenza
younger than 2 or 65+ COPD/asthma Chronic cardiovascular, renal, hepatic dz hematologic dz (sickle cell) metabolic dz (DM) immunosuppression HIV aspiration pregnancy chronic ASA neuromuscular d/p, seizure d/o
What are the complications of rubella to a fetus
fetal death hearing loss cataracta retinopathy mental retardation cardiac abN
What are the signs and symptoms of yellow fever
fever, chills, N/V, remission then fever, jaundice, hemorrhage and black vomit
What are the signs and symptoms of Dengue
fever, arthralgias, weakness, severe bone pain, coagulopathy
Dengue hemorrhagic fever: thrombocytopenia, increased permeability, 5% mortality
What are the signs and symptoms of West Nile Vilus
fever, malaise, encephalitis (LOC, parkinsonian movement), meningitis, rash, lymphadenopathy
What are the signs and symptoms of SARS
presence of 2+, fever GT 38, chills, rigors, myalgias, H/A, diarrhea, sore throat, severe disease with resp distress/ARDS
What are complications of mumps
orchitis encephalitis Guillain-Barre pancreatitis myocarditis arthritis
What are the signs and symptoms of polio
non-specific URTI, , meningitis, severe paralysis, death
List 4 ways rabies can be transmitted.
· Bite wound
· Mucous membrane exposure of virus
· Organ transplant from infected donor (incl cornea)
· Scratch (rare)
· Aerosol, ingestion (experimental conditions)
Top 5 species with rabies in Canada 2013
· Foxes · Skunk · Bat · Dog · Raccoon Others from globe: · Cats · Jackal (like a coyote) · Mongoose
List clinical signs of rabies in the animal.
- Aggressive behaviour
- Ataxia
- Irritability
- Anorexia
- Lethargy
- Excessive salivation
- Change in instinctive behaviour (i.e noctural animal in active during the day)
What are the 5 clinical stages of rabies infection?
- Incubation – (20-90 days typical)
- Prodrome – 1 week
· Numbness or pain at bite site
· Flu like symptoms - Acute neurologic illness – 7-10 days
· Furious: Encephalopathic (80%)
o Agitation increased with exposure to light, noise, thirst, fear
o Hydrophobia à inability to swallow; ++ a/w protective reflexes, resulting in diaphragm contraction, ++accessory muscle use
o Aerophobia à phobia of air in motion (ie blowing on face)
o Fluctuating LOC
o Irritability
o Autonomic dysfunction à tachy, febrile, priapism, excessive salivation
o Increased reflexes, +ve Babinski, nuchal rigidity
· Dumb: Paralytic (20%)
o Limb weakness
o Fever
· Non-classic (Rare, Thailand from dogs, bats)
o Ataxia, nystagmus, vertigo
o Brainstem signs
o Pronounced motor and sensory deficits - Coma (7-10 days after Sx onset)
- Death (12-13 days after Sx onset)
- Prodrome – 1 week
After a bite, how is rabies prevented (Post exposure prophylaxis KNOW THIS)
If bite from dog or cat presumed to be rabid or a racoon, skunk, fox, bats consider immediate prophylaxis
otherwise discuss with MOH
What is appropriate wound care after bite
aggressive scrubbing, soap, water, swabbing deep wounds and rinsing with iodine
List steps in rabies immunoprophylaxis.
Human rabies immune globulin. 20IU/kg into wound. Any remaining volume should be administered IM at distant site from vaccine
Give vaccine at days 0,3,7,14
· List 6 Risk factors for C diff
Ø Age >65 Ø Recent ABx use (commonly 3 weeks, as long as 6 months) Ø Severe underlying illness Ø NG intubation Ø Use of antinuclear medications Ø Prolonged hospital stay
List abx associated with c diff
· Antibiotics associated with it: Ø Clindamycin Ø Penicillins Ø Cephalosporins Ø Tetracyclines Ø Sulfa Ø Macrolides
List mgmt of non-toxic c diff and toxic
· Non-toxic management
Ø Flagyl 250 mg po qid X 10 days
Ø Vancomycin 250 mg po qid X 10 days is an alternative
Ø NO antimotility agents
· Toxic patients
Ø Vancomycin 500 mg po qid X 14 days (does NOT work iv!!)
Ø Flagyl 250 mg po or iv qid X 14 days (po preferred but it DOES work iv)
Ø Occasionally require hemicolectomy
Ø No antimotility agents
