Disease States and Treatments Test 2 Flashcards
Steps in the Pathogenesis of an Infection
Encounter –> Colonization –> Evasion of Host Defenses –> Invasion –> Mechanisms of Damage –> Shedding
Bacteriocins
when the indigenous flora secrete their own antibiotics that inhibit growth of other org around them so they don’t have to compete for nutrients
Virulence
degree of pathogenicity of an org
Virulence factors
genetically related factors that demonstrate biochemical evidence of damaging potential
Can be defensive (attachment, recognition, proliferation, change in surface structure to avoid recognition) or offensive (damage, toxin prod, spread)
Exotoxins and Examples
substances that, if isolated and injected, would elicit sx of infection
Ex. tetanus, botulinum, diphtheria, anthrax
Endotoxins and Examples
substances that are kept w/in bact but that are released upon destruction of bact cell wall
Ex. Almost always refers to LPS!
Tamm-Horsfall mannoproteins
normal host defense in bladder to keep substances from adhering to bladder wall; decoy for mannose
Umbrella cells
protective barrier for the lining of the bladder; secrete mucin
Cystitis
LOWER UTI in females; just involves the urethra and bladder
Pyelonephritis
UPPER UTI in females; tend to involve the kidneys as well as urethra and bladder
When do you categorize a UTI as complicated?
Male, Age >65, children, pregnancy, diabetes, immunosuppression, indwelling catheter, instrumentation, anatomic abnormality
Main org in UTI?
E.coli, Staph saprophyticus
Diagnosis of UTI
MADE PRIMARILY BY SX AND SUPPORTED BY DIAGNOSTIC TESTS!
Diagnostic tests: leukocyte esterase, WBC’s >10, nitrite, >5 RBC’s, bacteria
First line for uncomplicated lower UTI
TMP/SMZ (Bactrim) bid x 3 days OR
Nitrofurantoin (Macrobid) bid x 5 days
Treatment for complicated lower UTI
Quinolones preferred x 7-10 days (Cipro or Levo)
First line for pyelonephritis
Upper UTI (always want a urine culture); Ciprofloxacin or Levofloxacin
2nd TMP/SMZ
NEVER USE NITROFURANTOIN IN UPPER UTI!
Treatment of UTI in males (non-prostatitis)
Cipro or Levo x 10-14 days
First line for prostatitis in males
Cipro or Levo OR TMP/SMZ
Acute= 4 weeks (lots of pain)
Chronic= 6 weeks (low back pain and less severe sx)
Asymptomatic bacteriuria
not treated unless there are symptoms EXCEPT IN pregnant women and invasive urologic procedures
Nonpurulent Cellulitis
Swelling, redness, (erythema and edema at site of infxn); Strep pyogenes
Purulent Cellulitis
Involves a lesion of some sort (boils, abscesses); Staph aureus; require incisions and drainage!
Degree of Severity of Cellulitis
Mild= local only Moderate= systemic sx (fever, >WBC's, chills, etc) Severe= SIRS, hypotension, failed initial tx, immune compromised
Treatment for mild nonpurulent cellulitis
penicillin, diclox, C1, clindamycin
Treatment for moderate nonpurulent cellulitis
penicillin, cefazolin, penicillinase resistant penicillin, clindamycin
Treatment for severe nonpurulent cellulitis
Vanc PLUS pip/tazo
Treatment for mild purulent cellulitis
not necessary! (don’t even need them if you got rid of the boil)
Treatment for moderate purulent cellulitis
TMP/SMZ, doxycycline
Treatment for severe purulent cellulitis
Vanc
Treatment for necrotizing infections
Penicillin + Clindamycin
Polymicrobial: Vanc + pip/tazo
Treatment for bite wounds
Augmentin or ampicillin/sulbactam x 10-14 days
Diabetic Foot Infections Duration and Diagnosis
Only valuable cultures are from debridement
Treat for approx 14 days
Hematogenous
spread through bloodstream
Contiguous
spread from nearby infection
Kernig’s sign
pain with extension of the leg (meningitis)
Brudzinki’s sign
raises the neck and it causes flexion of the knees
Diagnosis of meningitis
definitive by lumbar puncture; increased opening pressure, increased WBC, decreased glucose (50)
Steroids as adjunctive therapy in CNS infections
MUST give steroids PRIOR to first dose of antibiotics to be effective (used to prevent new inflammation from the lysing of dead bact from abx)
Usually dexamethasone
Do NOT enhance passage across BBB
Treatment for meningitis for <1 month olds
ampicillin + -tax OR -triax
Add ampicillin to cover Listeria in the youngin’s
Treatment for meningitis for 1 mo-60 years old
Vanc + -tax OR -triax
Treatment for meningitis for >60 years old
Vanc + ampicillin + -tax OR -triax
Dosing for meningitis agents
Ampicillin: 1 gm Q4H
Cefotaxime: 1 gm Q4H
Ceftriaxone: 1 gm Q12H
Vancomycin: 30-40 mg/kg/day
Prophylaxis for meningitis
Rifampin
5 ways you can get infections from catheters
1.) contaminated infusate 2.) contaminated hub 3.) skin organisms 4.) contamination of device prior to insertion 5.) hematogenous
Diagnosis for catheter related blood stream infections
2 sets of blood cultures (one catheter and one blood)
Treatment of catheter related blood stream infections
Vanc is first line!
High dose daptomycin alternative
De-escalation of therapy in CRBSI
Based on culture results=
MSSA/ MSSE: nafcillin/oxacillin
Enterococcus: ampicillin/ Vanc + AG
Gram (-) bacilli: beta-lactams
Antibiotic lock therapy
instill high conc antibiotic into the catheter and leave 24-48 hours
