ID CPS Flashcards
(325 cards)
What is the risk of mortality from IE due to strep viridans infection of prosthetic valves vs. of native valves?
Prosthetic valves: 20%Native valves: 5%
What are the 7 indications for prophylaxis against IE in patients undergoing dental procedures?
- Previous infective endocarditis2. Prosthetic cardiac valves3. Cardiac transplant recipients who develop cardiac valvulopathy4. Unrepaired cyanotic congenital heart disease (including palliative shunts and conduits)5. Completely repaired cyanotic CHD with prosthetic material or device during the first 6 months after procedure (ie. until endothelialization of prosthetic material occurs)6. Repaired CHD with residual defects at site of prosthetic patch or device (incomplete endothelialization)7. Rheumatic heart disease if prosthetic valves or material used in valve repair
What is the most common underlying condition that predisposes to the acquisition of IE in the western world?-prophylaxis prior to dental procedure?
Mitral valve prolapse-no abx prophylaxis since the absolute incidence of IE is extremely low in this population AND IE with MVP is usually not associated with horrible outcomes as in cyanotic CHD
Which dental procedures require abx prophylaxis for IE?
- Manipulation of gums2. Involvement of periapical region of teeth3. Perforation of oral mucosa
What is the preferred antibiotic for IE prophylaxis prior to dental procedure? -dose?-when to administer?-2nd option for allergic people
Amoxicillin (well absorbed, high serum concentrations)-50 mg/kg x 1 dose 30-60 mins before procedure OR up to 2 hrs after-2nd options: clindamycin or clarithromycin
What respiratory tract procedures requires IE abx prophylaxis for high risk patients?
Any procedure that involves incision or biopsy of the respiratory mucosa-ex. T&A
What GI or GU tract procedures requires IE abx prophylaxis for high risk patients?
Prophylaxis is no longer recommended in these patients UNLESS they already have an established GI or GU tract infection, then the abx should have activity against enterococcus (amp or vanco)
Most common clinical presentations of invasive group A strep infections?
TSS
Nec fasc
Bacteremia
Pneumonia
In pediatric populations, what is a prominent risk factor for developing an invasive GAS infection?
Varicella infection
Others: recent pharyngitis, NSAIDS, household contact, recent soft tissue trauma
What is the diagnostic criteria for GAS Toxic Shock Syndrome?
Hypotension + at least two of the following:
- Renal impairment
- Coagulopathy (decreased platelets or DIC)
- Liver enzyme or function abnormality
- ARDS
- Generalized erythematous macular rash that may desquamate
**Think hypotension + involvement of at 2 organ systems (heme, renal, liver, derm, lungs)
Who is considered a close contact of a person with invasive GAS infection? (7)
- Household conatcts who have spent at least 4 hr per day on average in previous week
- Shared the same bed or had sex
- Direct mucous membrane contact (kissing, mouth to mouth resusc, touched open skin lesion)
- Injection drug users who shared needles
- Share long term care facility
- Share home daycare
- Selected hospital contacts
What is the recommendation on who should receive chemoprophylaxis for GAS invasive infection?-when should chemoprophylaxis occur?-what advice should be given to close contacts?
Who should receive:1. Close contacts of a confirmed case of SEVERE GAS invasive infection (TSS, nec fasc, meningitis, pneumonia) who have been exposed during the period from 7 d before onset of symptoms in the case to 24 hr after the initiation of abx in the case-chemoprophylaxis should start ASAP (within 24 hr of case identification is ideal but can be up to 7 d after the last contact with the case)-advise close contacts on s/s of GAS infection and to see MD asap if febrile or other s/s of GAS within 30 days of diagnosis in index case
What is the definition of confirmed case of GAS?
Laboratory confirmation of GAS infection (isolation of GAS from a normally sterile site) with or without clinical evidence of invasive disease
What is the preferred chemoprophylaxis agent for close contacts of GAS invasive infection?-alternative agents?-alternative agents for beta-lactam allergy?
1st generation cephalopsporin (cephalexin)-alternative agents: 2nd or 3rd generation cephalosporin (cefuroxime axetil and cefixime)-beta lactam allergy: macrolides (but concern with macrolide-resistant GAS) or clindamycin**NOTE: penicillin is LESS effective than cephalosporins for eradicating GAS COLONIZATION
What is the recommendation on whether routine cultures should be drawn on close contacts of GAS invasive infection receiving abx chemoprophylaxis?
No routine cultures are required unless symptomatic
What is the antibiotic of choice for treating severe invasive GAS infection?
- additional treatment to minimize/neutralize the effects of toxin production?
- additional treatment of GAS toxic shock syndrome?
Treatment of choice: penicillin (no resistance to date).
- add clindamycin to inhibit protein synthesis and thus decrease toxin production (should never be used as monotherapy though since 1-2% of GAS is resistant to clindamycin)
- for GAS TSS, add IVIG single dose 1-2 g/kg
What is Palivizumab?
- dose, route, timing of administration
- cost?
RSV-specific monoclonal antibody - used for preventing and reducing RSV hospitalization rate of high-risk children
- 15 mg/kg IM q30days during RSV season x 5 months
- cost of 1 course: ~$5600 (more than cost of average stay in hospital for RSV)
- no evidence showing that it prevents significant mortality
The majority of RSV hospitalizations occur in what group of infants?
Term infants with no pre-existing risk factors
What is the drug efficacy of palivizumab for prevention of RSV and associated hospitalizations?
NNT is about 20 (depending on RF)
Which high-risk children should receive palivizumab to prevent RSV hospitalization?
- Significant CHD or CLD (ongoing diuretics, bronchodilators, steroids, 02) and age < 12 months
- Prem < 30 weeks and age < 6 mos
- Prem < 36 wks in remote communities and age < 6 mos
- Term Inuit, living in community with high RSV rates and < 6 mos
Other: Home O2, hospitalized for pulmonary disease, severe immunocompromised and <2 years
NOT recommended : T21, immunodeficiencies, CF routinely
What is the recommendation for use of palivizumab in infants in remote communities who would require air transport for hospitalization?
- Should consider giving to babies born < 36 weeks
What is the recommendation for use of palivizumab in children with immunodeficiencies, Down syndrome, cystic fibrosis, upper airway obstruction or a chronic pulmonary disease other than chronic lung disease of prematurity?
Not routinely recommended BUT may be considered for children < 24mo who are on home O2, have had
prolonged hospitalization for severe pulmonary disease, or who are severely
immunocompromised.
What is the incubation period of chicken pox?
10-21 days after contact
When is the highest concentration of VZV DNA detected in the nasopharyngeal secretions in terms of day of rash? -when is transmission the greatest?
Highest concentration on day one of rash-the children with the highest level of viremia will obviously be the sickest with higher fevers and more vesicles-transmission is the greatest in the prodrome period (the day before onset of rash)