Infectious Disease Flashcards
What are the risk factors for Hib meningitis?
Partially immunized Unimmunized New to Canada Immunosuppressed Immune-incompetent
Who is at risk for listeria meningitis?
Age (neonate)
immunocompromised
brainstem symptoms as initial presentation
Drug of choice for GBS infection?
Penicillin
What are the contraindications to an LP?
Coagulopathy
Cutaneous lesion at proposed puncture site
Signs of herniation
Unstable pt
What are your empiric Abx choices for meningitis >1 mo and why?
What Abx do you add if worried about listeria?
Ceftriaxone 100mg/kg/day div q12
(Or cefotaxime 300 mg/kg/day div q6h)
Vanco 60 mg/kg/day div q6h
- ceftriaxone bc some strep pneumo and n menin are penicillin resistant
- vanco bc a small portion of strep pneumo is resistant to 3rd gen cephalo
Ampicillin 300mg/kg/day div q4-6h
What is the drug of choice for close contacts of pt with meningococcal disease or Hib?
Rifampin
When do we give steroids for meningitis and why?
Hib
Shown to decrease hearing loss
-some experts say if suspect bacterial etiology start iV steroids within 30mins of antibiotics and continue q6h (total 2 days doe strep pneumo and Hib)
In which cases of meningitis should you do a repeat LP?
Gram negatives (eg E. coli) at 24 to 48h HSV meningitis (near end of 21 day course)
How long do we treat meningitis due to: A) strep pneumo B) Hib C) n meningitides D) GBS
A) 10-14 days
B) 7-10 days
C) 5-7 days
D) 14-21 days
What are the main bugs for kids with meningitis >1 month?
H flu type b (rare…now more non typable)
N meningitides
Strep pneumo
GBS and E. coli if child is
How is C. diff spread and what is the incubation period from time of exposure?
Fecal-oral
2-3 days
What are risk factors for C diff infection?
Duration of hospital stay Older age Exposure to multiple Abx classes Chemotherapy Immunosuppression Hypogammaglobulonemia GI surgery
What are the important pathophysiological features of C diff?
Heat resistance of spores
Acid resistance of spores
Toxin production (A enterotoxin, B cytotoxin)
What are the diagnostic criteria for C diff?
Presence of symptoms (usually diarrhea) PLUS stool test positive for toxin OR scope showing pseudomembranous colitis
Which populations are most likely to have complications from c diff?
Neutropenic oncology kids
Stem cell transplant recipients
Infants with hirschsprungs
IBD pts
What tests are commonly used for dx of C diff?
- Enzyme immunoassay (EIA) for glutamate dehydrogenase
- EIA for toxins A and B
- Cell cytotoxic assay
What is the treatment for mild, mod, severe, severe/complicated c diff?
Mild - stop Abx
Mod - stop Abx, metronidazole PO 30 mg/kg/day div q6h x 10-14 days
Severe - stop Abx, vanco PO 40 mg/kg/day div q6h x 10-14 days
Severe/complic - stop Abx, Vanco PO PLUS IV flagyl 30/mg/kg/day q6h x 10-14 days
How do we treat first and second recurrences of c diff?
First recurrence- same as initial
Second - Vanco PO wih tapered or pulsed regimen
*there may be a role for probiotics in preventing recurrences
How recently should a pt have had Abx in order to include c diff in the differential?
Within the past 12 wks
What is the worst manifestation of pseudomembranous colitis?
Toxic megacolon
What groups are at risk for invasive meningococcal disease?
- Anatomical or functional asplenia
- Primary antibody deficiency disorders
- Complement, properdin or factor d def
- Travelers to areas where meningococcal risk is high
- Lab personnel with exposure to meningococcus
- The military
What are the 2 types of meningococcal vaccines, what strains do they cover and what age should they be given?
Meningococcal serogroup C conjugate (MCV-C)
- serogroup C
- all infants age 12 months (even if had doses before age 1 yr they need a dose at 12 mo)
- high risk kids can start with doses at 2 and 4 months
- adolescent booster if don’t get quadrivalent
Quadrivalent Meningococcal conjugate (MCV-4) -Types A, C, Y, W-135 -booster in adolescence -kids >2 yrs at increased risk for meningococcal disease
What is the most common cause/strain of meningococcal infection in Canada and why don’t we vaccinate against it?
Meningococcal serogroup B
(Esp in kids under 5 yrs)
-polysaccharide of serogroup B is poorly immunogenic in humans so hard to dev a vaccine
-vaccine came out last year against it (bactero) but not publicly funded yet
Does having a primary rsv infection confer protective immunity?
No. Reinfections continue into adulthood
What are nonpharmacologic ways to prevent spread of RSV to high risk children?
Good hand hygiene at home
Limit contact with kids/adults with URTI symptoms
Which high risk groups should get palivizumab?
CLD of prematurity age
What lab testing do you do to see if pt is immune to varicella with natural disease? After vaccine?
IgG to VZV for natural disease
No commercially available testing for ppl who have received vaccine (reference labs can do gpELISA and FAMA test)
Define primary and secondary vaccine failure
Primary - after vaccine given, a protective immune response does not develop
Secondary - waning immunity
What are the limitations of single dose varicella vaccine?
- case numbers have plateaued
- shift in median age of disease onset (adolescents and adults have more severe complications)
- waning immunity over time
What is most common adverse event with varicella vaccine?
Pain and redness at injection site
CPS recommends 2 doses of varicella vaccine for kids 1-12yrs. When should the first and second dose be given?
first dose: Btwn 12 and 18 months
- second dose:
- age 4-6 yrs
- > 3 months after the first dose (> 1 month apart for kids over 12 yrs)
What specific at risk population should be screened for varicella immunity and what should you do if they are not immune?
Pregnant women
When no longer pregnant then give vaccine (ok to give if breastfeeding)
What is acceptable to consider someone immune to varicella?
- IgG to VZV (natural disease)
- documentation of 2 doses of vaccine (do NOT do serology)
- lab confirmation of varicella or herpes zoster from a lesion
- previous dx of varicella or herpes zoster by a HCP
What are the benefits of home IV therapy?
Improved quality of life
Lower healthcare cost
What are the indications for home IV therapy?
- Infections req prolonged IV Abx (eg bone and soft tissue, endocarditis post stabilization, cmv, fungal)
- hemophilia for factors
- palliative care
- chemo
- immune deficiencies
- anti inflammatory mediators
What is the most common complication of home IV therapy?
Mechanical (eg. IV insertion, dislodgement, thrombosis, occlusion)
What infrastructure do you need in place to do home IV therapy?
Home IV therapy team
Facilities to insert vascular access devices
Available infusion pumps and equipment
Protocols
Who should be on the IV home therapy team?
Physician Primary care provider Infusion nurse specialist Home care Ppl with skills in vascular access Pharmacist SW, specialists prn
*pt should be seen at least once a week by RN or MD
What are some patient and family factors to consider when doing home IV therapy?
Willing to participate
Understand importance of compliance
Require adjustments to schedules and sports/activities
Understand benefits/risks
Can learn skills needs reliably
Understand economic implications (may not be entirely covered)
Have schedule flexibility
Able to rapidly communicate with IV team
Adequate housing conditions
Safe home environment (eg no substance abuse)
What are antibiotic factors important in home IV therapy?
Can be given in programmable electronic pump
Stable at room temperature at least 24h
Stable in fridge at least one week
What are the types of vascular access devices for home IV therapy?
PIV Midline catheter PICC Tunneled line (broviac or Hickman) Port
What monitoring is required for pts on home IV therapy?
Ongoing evaluation of illness being treated
Evaluation of vascular access site
Compliance
Monitor for adverse drug effects +- drug levels
What are the benefits of a harmonized immunization schedule for Canada?
- safer and equal access across Canada
- larger bulk purchase of vaccines
- educational information simplified
- new programs introduced in organized fashion
- HCP do not need to learn a new schedule if they move provinces
How is rotavirus transmitted? What is its incubation period? Main symptoms? Avg # of days to resolve? What age do we commonly see infection?
Transmission: Fecal-oral and fomites Incubation: 1-5 days Main Sx: vomiting, fever then diarrhea Days to resolution: 3-8 days Age: less than 5 years, more severe in kids
If mortality from rotavirus is rare why do we recommend a vaccine?
Significant health care resource use associated with rota infections.
How do we diagnose rotavirus?
antigen detection in stool by enzyme immunoassay
What was the reason of recall for the previously licensed Rotavirus vaccine RotaShield?
increased association with intussusception
When should a child be vaccinated against rotavirus? How many doses and by when should it be complete?
Two approved vaccines either 2 or 3 doses depending on the brand.
Vaccine must start at 6 to 14+6 weeks of age and completed by age 8 months.
**can be given with other vaccines
Do shed the virus with vaccine administration.
What are the contraindications to the rotavirus vaccines (RotaTeq and Rotarix)?
- hypersensitivity to vaccine or any of its components
- history of intussusception
- known or suspected immunodeficiency
Should kids who have had rotavirus infection get the vaccinations?
Yes b/c infection only provides partial immunity but they must be in the recommended age range.
What is the pathophysiology of AOM?
Eustachian tube dysfunction and obstruction:
1) viral infection causes obstruction of eustachian tube
2) impaired mucociliary clearance (mucus trapped in middle ear)
3) resorption of gasses causes pressure differential and vacuum which pulls bacteria from nasopharynx into middle ear
What are the risk factors for AOM?
MAJOR
- young age
- daycare attendance
OTHER
- orofacial abnormalities
- household crowding
- exosure to cigarette smoke
- prematurity
- not being breastfed
- immunodeficiency
- positive family history
- first nations/aboriginal
What are the diagnostic criteria for AOM?
1) Signs of middle ear effusion
- immobile TM, +/- opacification/loss of bony landmarks/ruptured with fluid
2) Signs of middle ear inflammation
- bulging and discoloured TM
3) Symtpoms
- irritability, acute ear pain
What are the main bugs that cause AOM?
Streptococcus penumoniae
Hemophilus influenzae
Moraxella catarrhalis
For who can you use the watchful waiting approach in AOM? (48 to 72h)
- older than 6 months
- no immunodeficiency, chronic heart/lung condition, T21, orofacial abnormality, or hx of complicated OM (suppurative complications or chronic perf)
- illness not severe (temp is
What are the biggest complications of AOM we worry about?
mastoiditis
meningitis
intracranial abscess
Strep pneumo has increasing abc resistance, what are the RF for abx-resistent Strep pneumo for AOM?
- age 4h per week with at least 2 unrelated kids)
- frequent AOM
- recent abx use
- failed initial abx treatment
What is first line tx for AOM?
First line if have a type 1 run (anaphylaxis or urticaria to amoxil)?
First line if non-type 1 run to amoxil?
First line:
Amoxicillin 75-90 mg/kg/day
Type 1 rxn to amoxil:
Clarithromycin or Azithromycin
non-Type 1 rxn to amoxil:
2nd generation cephalosporin (eg cefuroxime)
If symptoms of AOM do not improve by 2 days, what abx should you change to?
Amox/Clav 90 mg/kg/day of amoxil component bid x 10 days
OR
Ceftriaxone 50 mg/kg/day IV OD x 3 days
How long should you treat AOM?
5 days for most
10 days if:
-age
What reduces a child’s risk of AOM?
Hand washing Exclusive breastfeeding until age 3 months Not using pacifiers before age 3 years Limiting daycare Not smoking
What is the incubation period for varicella-zoster virus?
How long before the rash appears are you contagious?
How is varicella transmitted?
Incubation: 10-21 days (avg 14-16 days)
Infectivity: 24-96 hrs before rash onset
Respiratory (as per CPS) but is airborne
When should a child with chickenpox return to school/daycare?
When well enough to participate normally in all activities.
Does not matter the state of the rash
How long should hospitals keep their varicella patients in isolation?
8 to 21 days from the time of contact with the infected person
How are head lice spread and how do you diagnosis a head lice infestation?
Spread through head-to-head contact
(they do not hop or fly!)
Must detect a living louse (a nit does not count!), best method is using a fine toothed comb.
How long can adult head lice and nymphs (babies) survive away from the human host?
3 days
How do you treat head lice?
Does itching post treatment mean reinfestation?
Topical insecticides (2 applications 7-10 days apart) e.g. permethrin or pyrethrin -is a new non-insecticidal product
NO! can be due to irritation from treatment, must have live louse to diagnose reinfestation
1) How long should kids stay out of school with a head lice infestation?
2) What does that mean for other kids in the class?
3) What do you do with household contacts and household items?
1) Do not need to be excluded (including if have nits).
2) Inform parents about active head lice case in the class and how to check for it.
3) wash items in contact with the head in hot water (66 degrees C) and then the dryer for 15 minutes or store in occlusive plastic bag x 2 weeks; check household contacts for live louse
For which of the following chronic infections can kids be excluded from daycare?
A) hep b
B) hep c
C) hiv
None
How is hep b transmitted? Under what circumstances would a bite potentially result in transmission?
Transmitted via mucous membranes or open skin lesions with blood, saliva, or genital secretions from an infected person
-only if there is a break in the skin is there a potential for transmission
Under what circumstances is post exposure prophylaxis indicated for hep b after a bite?
- kid with hep b bites another kid and breaks the skin
- kid who is not infected who bites a kid with hep b if the blood from bthe kid who was bitten comes in contact with the biter’s oral mucosa
Are parents of hiv positive kids required to report the hiv status to the child care personnel?
Nope
Under what circumstances is post exposure prophylaxis indicates for hiv after a bite in daycare?
Very rarely Bc transmission via saliva is very low. Only give in consultation with Peds ID.
What specific treatment can be offered after a bite at daycare involving a kid with hep c?
None. No prophylaxis currently available.
Need serology at 6 months
What information should be given to parents prophylactically about bites at daycare?
If bite with significant blood exposure occurs parents of both kids will need to be informed of the incident and may be referred for medical evaluation.
Under what circumstances can a kid with hep b be excluded from daycare?
If frequent aggressive biter
Assessed on individual basis by kids doctor and public health
What are measures to decrease biting at daycare? (8 answers)
- avoid stressful situations and conflicts
- provide small group, age appropriate activities
- observe how, when and why a kid bites to guide management
- pay attention to the victim first
- firm statements to biter that behaviour is inappropriate
- direct biter to appropriate activities
- positive reinforcement of appropriate activities
- collaboration with family
What can be done as prophylaxis at a daycare for hep b?
All staff should be immunized
Parents should be encouraged to have their kids vaccinated
Can offer it to kids without revealing the identity of the infected kid.
What do you do when a bite happens at daycare if skin not broken? Broken?
Not broken
- clean with soap and water
- apply cold compress
Broken skin
- allow to bleed gently, don’t squeeze
- Clean with soap and water
- apply mild antiseptic
- write official report
- report bite to public health
- parents of both kids should be notified
- review and update tetanus status
- consider if need prophylactic antibiotics
Under what circumstances should prophylactic antibiotics be used for a bite in daycare?
Moderate or severe tissue damage
Deep puncture
Bites to face, hand, foot, genitals
What is post exposure prophylaxis for hep b?
Hep b immunoglobulin (0.6ml/kg IM) and hep b vaccine if kid involved is incompletely immunized or non immune
If hep b status of one (or both) of the kids is unknown and bite breaks the skin, give hep b vaccine
- -> need f/u to complete hep b series
- -> hep b serology at 6 months if known hep b exposure
How quickly should post exposure prophylaxis be given after a bite involving hiv positive kid?
Within a few hours of the exposure
Not indicated if more than 72 hrs have passed
What are the major risk factors for seropositivity of Hep C in pregnant women? (4)
Current or past IVDU
Dating an IVDU
Blood transfusion before 1990/fr developing country
Recipient of organ or tissue transplant from unscreened donors
What is the definition of chronic Hep C infection?
Acute phase is usually subclinical
active viral replication for more than 6 months
*some kids have had spontaneous clearance of Hep C infection after 6 months
What is the most common lab finding and physical finding for Hep C in kids?
intermittent/chronically elevated aminotrasferase
heptomegaly
What are the risk factors of increased risk of transmission of Hep C from infected mum to baby? (4)
high maternal viral titre
elevated ALT in year before pregnancy
maternal cirrhosis
HIV coinfection (if on antiretrovirals this risk may be eliminated)
How does vertical transmission of Hep C occur?
intrauterine AND intrapartum
NOT via breastmilk (should breastfeed unless bleeding nipples)
What can be done to prevent vertical transmission of Hep C? What is the transmission rate?
nothing
5%
What body fluids are the major source of transmission for Hep c?
blood
No known risk from saliva, urine or stool
When should Hep C serology be done in a newborn born to a hep C positive mum and why?
- age 12-18 months, repeat at 18 months if done prior and was positive
- minimum age is 2 months but not recommended routinely (only if ++parental anxiety or concern re: loss to f/u)
- b/c before that get passive maternal antibodies
What is your management of a child with Hep C RNA positive as an infant?
Repeat HCV RNA and ALTs q6months (to see if will become chronic or have spontaneous clearance)
What are the longterm sequelae of chronic hep c infection for kids?
Liver disease
hepatocellular carcinoma
How would you interpret the following of a baby born to Hep C positive mum >18 months?
+HCV antibody
HCV RNA PCR not detected
Clearance of Hep C virus (occurs in 25%)
How would you interpret the following of a baby born to Hep C positive mum >6 months?
+HCV antibody
HCV RNA PCR detected >6 months
Chronic Hep C infection
How would you interpret the following of a baby born to Hep C positive mum at any age?
+HCV antibodies
HCV RNA PCR detected
Acute Hep C infection
What are risk factors for transmission of bugs in the outpatient peds setting? (6)
- kids who can’t handle their secretions well
- diarrhea in diapers/incontinent
- open wounds/lesions
- organisms that can survive on inanimate objects for long periods of time
- crowded waiting rooms
- being immunocompromised
What bugs are transmitted via the airborne route?
Measles
TB
Varicella
What precautions do you use for meningitis?
Droplet
What precautions do you need for influenza?
Droplet + Contact
b/c can survive on surfaces
What is the difference between droplet and airborne?
Droplet - large droplets that do not stay suspended in the air, must wear mask within 2m of the patient
Airborne - small droplets that stay suspended in the air and can be dispersed over large areas, N95 and negative pressure rooms
How often do hard toys need to be washed at a Dr’s office and how?
q1-2weeks
cleaning and soaking for 1 h in bleach solution (1:100 dilution)
Name some measures in office design to minimize spread of infection?
- ventilation with at least 6 exchanges per hour
- no carpets
- handwashing sinks with adjacent soap and paper towel
- signs about coughing into a tissue or your sleeve
Under what conditions should a kid not wait in the waiting room at the doctors office?
- immunocompromised
- ideally those with contagious illnesses (fever, diarrhea, vomiting, cough, open skin lesions)
- anyone with suspected airborne illness (measles, TB, varicella)
What are the moments of hand hygiene?
before contact with patient
after contact with body fluids
before invasive procedures
after contact with patient
What do you use in the Dr’s office to clean spills of bloody body fluid?
bleach 1:10 to 1:100 dilution
wear gloves
How long does it take for the air to be free of aerosolized particles from an airborne illness? aka how long til the examining room can be used again?
70 minutes
What special precautions do you need to use for patients with antibiotic resistant organisms (e.g MRSA, VRE)?
Routine practices
Emphasis on hand hygiene
What vaccine immunity should you check of the personnel who work at a Dr’s office?
Immunity to:
- MMR
- varicella
- Hep B
- Polio
- one dose of acellular pertussis as an adult
Should have negative documented TST
How long should personnel at Dr’s office avoid direct care of high risk patients if have URTI?
until symptoms resolve
How long should personnel at Dr’s office avoid direct care of high risk patients if have Hep A?
until one week after onset of jaundice
How long should personnel at Dr’s office avoid direct care of high risk patients if have conjunctivitis?
until exudate resolves
How long should personnel at Dr’s office avoid office of high risk patients if have Rubella?
until 7 days after onset of rash
What are 5 factors that are important for a screening program?
- sensitivity and specificity of the diagnostic test
- acceptability and feasibility of the diagnostic test (easy to administer)
- benefit of early detection
- disadvantages of testing
- prevalence of disease
How do you diagnose HIV infection?
1) screening with enzyme immunoassay
2) confirmatory test with western blot **only done for HIV-1 in Canada
- must do pre and post test counselling
What is the window period for HIV infection? (from infection to detectable antibodies)
4-6 weeks
How do you interpret an indeterminate western blot for HIV?
- early infection
- infection with HIV-2 (b/c we only test for HIV-1)
- waning maternal antibodies in an infant
- false positive
Which pregnant women should be screened for HIV?
all of them
How does vertical transmission of HIV occur?
- time of delivery
- via breastmilk (9% risk of transmission per year of breast-feeding)
- avoid breastfeeding even if on antiretrovirals
What is the major risk factor for perinatal transmission of HIV?
maternal viral load
How should a baby of an HIV-positive mum be delivered?
-c-section or vaginal delivery if viral load
If a women is HIV positive and pregnant should she be on antiretrovirals?
Yes (benefits outweigh the risk of toxicity in utero)
What is the perinatal transmission rate of HIV if no interventions are taken?
25%
What is the management of an infant born to an HIV positive mother?
Refer to ID
needs AZT and possibly combo therapy
Why do we give 2 doses of the rubella vaccine?
Failure of one dose of vaccine is as high as 10%
What can we do to minimize congenital rubella syndrome?
- screen women in pregnancy and if not immune give them the vaccine post partum
- screen newcomers to Canada
What are the manifestations of congenital rubella syndrome in an infant?
microcephaly cataracts glaucoma pigmentary retinopathy hearing impairment PDA HSM thrombocytopenia radiolucent bone densities
What testing should you do for patients with illnesses compatible with rubella or measles?
IgM (rubella and measles) IgG serology (look for a 4-four increase in the titre) and/or virus detection
When can rubella vaccine be given to a pregnant woman?
28 days after delivery
- breastfeeding is NOT a contraindication
- contraindicated if have immune deficiency
What are the complications of rubella vaccine for postpartum women?
transient acute arthritis or arthralgia
Define: biocide sterilant disinfectant sanitizer fungicide
- Biocide: synthetic/semisynthetic agents that kill living cells above certain concentrations
- Sterilants: kills all forms of microbial life
- Disinfectant: eliminate infectious pathogenic bacteria
- Sanitizer: reduce microbial contaminants
- Fungicides: destroy fungi on inanimate surfaces
What are the pros and cons of alcohol-based antiseptics in the household?
- need 60-95% alcohol
- denatures proteins
- good against rota, adeno, rhino, hep A, poliovirus
- less active against bacterial spores, some non enveloped viruses and protozoan oocysts
What are the pros and cons of chlorhexidine in the household?
- active against gram-positive bacteria, less against gram-neg and fungi
- not sporicidal
- acts against enveloped viruses (HSV, HIV, CMV, flu)
- not as good against non enveloped viruses (rota, adeno, enter)
What are the pros and cons of triclosan in the household?
- incorporated into soaps
- 0.2-2% concentrations have antimicrobial activity
- often bacteriostatic
- better against gram-pos
- reasonable activity against mycobacteria and candida
What are the pros and cons of quaternary ammonium compounds in the household?
- mainly bacteriostatic and fungistatic
- more active against gram-pos
- less common against gram-neg bacilli
What are mechanisms microorganisms have developed to be resistant?
- enzymatic inhibition
- membrane impermeability
- efflux pumps
- alterations of ribosomal target
- alteration of cell wall precursor target
- alteration of alteration of target enzymes
- overproduction of target enzymes
- auxotrophs that bypass inhibited steps
What are important aspects for hygiene of the skin at home?
- mild, plain soaps are best
- no data to support bathing with antimicrobial products
- antiseptic hand products if close contact with neonates, old ppl, immunocompromised ppl
How long should you wash your hands for to prevent spread of respiratory viruses?
15-20 seconds
How should you handle diarrhea and vomiting at home?
- frequent handwashing, esp after diaper change
- disinfect contaminated surfaces with chlorine bleach-based cleaners
- if there is a spill clean with 1 part bleach to 9 parts water and let sit for 20 mins
How should you clean toys at home?
-if machine washable put them in the dishwasher
What are CPS recommendations for antimicrobial product use in the home?
Does not recommend their use
What are the CPS recommendations for egg-allergic patients and the flu vaccine?
All egg-allergic its should be vaccinated with a full dose of the INactivated vaccine, unless previous documented anaphylactic rxn to flu shot
(live attenuated not yet studied). Do NOT need skin testing or split doses.
Why don’t we give flu vaccines to kids
variable immune response and vaccine effectiveness unclear
What are the benefits of immunizing pregnant women against the flu?
- clinically effective
- safe
- cost effective
- lower maternal and infant flu-related hospitalizations
- decreased preterm and SGA newborns
What congenital anomalies are you at increased risk for if you get influenza during the 1st trimester?
- neural tube defects
- hydrocephaly
- CHD
- cleft lip
- digestive system defects
- limb reduction defects
Which flu vaccine should be given to pregnant women?
Trivalent inactivated vaccine
Which adolescents should be screened for STIs females and males?
Females: all who are sexually active or victims of abuse
Males: (at least one of)
- history of sex with someone with an STI
- personal hx of STI
- being a patient of an STI clinic previously
- new sexual partner or >2 partners in the past year
- IVDU or other drugs esp if assoc with sex
- usafe sex practices
- anonymous sex partnering
- sex workers/their clients
- street involvement/homelessness
- time in a detention facility
- experience of sexual assault/abuse
What is the most common symptom of rectal and pharyngeal gonococcal infections?
-often asymptomatic
When and how do you test for chlamydia?
WHEN TO TEST
- if have risk factors
- q6 months after infection if RF persists
- 3-4 weeks post tx if prepurbertal or if post pubertal and compliance uncertain or is pregnant
HOW TO TEST
- NAAT (nucleic acid amplification test) via first-catch void (can’t have voided in 2 hrs prior), vaginal, endocervical or urethral specimens
- need culture of cervix or urethra for medico-legal purposes
When and how do you test for gonorrhoea?
WHEN TO TEST
- risk factors
- 6 months after infection
- test of cure at 3-7 days if prepubertal or if use 2nd line tx, adolescent is pregnant, previous tx failure, pharyngeal infection, high re-exposure risk or symptoms persist
HOW TO TEST
- NAAT via first catch void, urethral and cervical samples
- should do Cx if possible b/c increasing abx resistance
- do Cx if:
- sexual abuse of child is suspected
- sexual assault cases
- tx failure presumed
- Pelvic inflammatory disease
- symptomatic MSM
- suspect acquired infection overseas or area with known resistance
When and how do you test for syphilis?
WHEN TO TEST
- if pregnant (ideally early on and at delivery)
- repeat RPR after treatment at 1, 3, 6 and 12 months post tx
- repeat RPR at 12 and 24 months in latent cases
HOW TO TEST
- Enzyme immunoassays is the best, if is positive need a second confirmatory test
- Rapid plasma reagin (RPR) but can be falsely negative early on
How do you treat gonococcal infection in children and youth?
If over 9 years use max adult doses
Cefritaxone 50mg/kg IM (max 250mg) PLUS Azithro 20 mg/kg (max 1g) PO x1
OR
Cefixime 8mg/kg PO bid x 2 doses (max 400 mg per dose or 800mg x1 if >9 years) PLUS Azithro
- *if pharyngeal do not use Cefixime, use Ceftriaxone PLUS Azithro
- **Always tx for both gonorrhoea and chlamydia even if test negative for chlamydia
Name some primary (3) and secondary (2) prevention strategies for STIs?
PRIMARY
- vaccinate against Hep B and HPV
- condom use
- behavioural change
SECONDARY
- partner notification
- tx and screening for STIs in asymptomatic young adults
What bacteria causes Lyme disease?
Borrelia burgdorferi
How is Lyme transmitted?
- via black-legged ticks (Ixodes scapulars and Ixodes pacific us) that live on mice, rodents, small mammals, birds, white-tailed deer, humans
- ticks can’t jump/fly
- wait on tall grass and attach when a host brushes past them
- immature ticks (nymphs) cause the most infections due to small size so ppl don’t see them
What is the peak incidence for lyme?
kids 5-9 yrs and adults 55-59 yrs
How long does a tick feed on its host?
5 days or more
After how long of being attached are you likely to get Lyme?
if remove within 24-36h of its feeding you are likely to prevent lyme disease
What do you need to do if a patient is dx with lyme disease?
Need to report it to public health
What are the clinical manifestations of lyme disease?
EARLY LOCALIZED
- erythema migrans (rash at site of tick bite…bullseye) usually after 7-14 days after the bite, macule or papule that expands centrifugally can have central clearing, can be flat or raise, usually >5cm diameter; usually painless, not pruritic; resolves in 4 wks
- can get fever, malaise, h/a, myalgia, arthralgia, neck stiffness
- can also have no rash
EARLY DISSEMINATED
- multiple EM lesions (usually several weeks after the bite, secondary annular erythematous lesions but smaller than the primary) - represents spirochetemia
- acute neurological signs (facial nerve palsy, papilledema, lymphocytic meningitis)
- lyme carditis (rare in kids)
LATE DISEASE
- rare if treated with abx
- pauciarticular arthritis affecting large joints (esp knees); can be weeks to months after tick bite, can happen without hx of earlier illness
- peripheral neuropathy and CNS manifestations
How do you diagnose early localized lyme? early disseminated and late disease?
EARLY LOCALIZED
- clinically + hx of potential tick exposure in area where there are suspected black-legged ticks
- antibodies often not detectable in first 4 weeks of infection
- all clinical manifestations of possible lyme (except EM) need lab confirmation
EARLY DISSEMINATED AND LATE DISEASE
- ELISA screening test then confirmatory Western blot
- most affected ppl have antibodies against B burgdorferi
- some ppl treated early with abx for early Lyme will never develop antibodies –> they are cured :)
- if have lyme meningitis intrathecal IgM or IgG might be helpful
How do you treat lyme disease?
Doxycycline if >8 yrs 4mg/kg/day divided bid
Amoxil if
What is the natural course of lyme arthritis?
- 1/3 have resideual synovitis and joint swelling which almost always resolves
- if persistent or recurrent joint swelling after tx then tx for another 4 wks
- if arthritis ongoing then consult an expert
What is the Jarisch-Herxheimer reaction in lyme disease? How do you treat it?
-fever, h/a, myalgia and an aggravated clinical picture lasting
What is post-treatment lyme disease syndrome and how common is it? How do you treat it?
- 10-20% of pts
- lingering fatigue, joint and muscle aches that last longer than 6 months
- NO benefits in giving long-term abx treatments
How do you remove a tick?
- fine-tipped tweezers
- pull upward with steady, even pressure
- do not twist or jerk
- if mouthpart breaks off and you cannot remove it easily, leave it in the skin
- clean the bit and hands with alcohol, iodine or soap and water
- keep the tick and bring to medical appointment if develop symptoms
How can we prevent lyme disease?
- landscaping
- 20-30% deet or icaridin repellents on clothes and exposed skin
- do full body check daily for ticks
- shower/bathe within 2 hrs of being outdoors
Should you treat a pt who has been exposed to a tick?
No consensus
Some say give a single dose of doxy if >8yrs within 72 hrs
Consider this if in a known endemic area
-no data for recommending amoxil to younger kids
What is the pathophysiology of acute otitis externa (aka swimmer’s ear)?
1) impaired local defense mechanisms due to prolonged ear canal wetness
2) desquamation causing microscopic fissures
3) entry of infecting organisms
What are risk factors for acute otitis externa?
- swimming
- trauma
- foreign body
- hearing aid
- certain dermatologic conditions
- chronic otorrhea
- wearing tight head scarves
- being immunocompromised
How does acute otitis externa present in terms of symptoms?
- otalgia
- itching
- fullness
- may have hearing loss
- ear canal pain when chewing
What is the distinguishing physical exam sign classic for acute otitis externa?
- tenderness of tragus when pushed
- tenderness of pinna when pulled
What do you need to diagnose acute otitis externa?
1) rapid onset (within 48h) in past 3 wks
AND
2) Sx of ear canal inflammation (otalgia, itching or fullness +/- hearing loss or jaw pain)
AND
3) signs of ear canal inflammation (tenderness of tragus or pinna OR diffuse ear canal edema/erythema +/- otorrhea, regional lymphadenitis, TM erythema, cellulite of pinna and adjacent skin)
What are the most common bugs that cause acute otitis externa?
Pseudomonas
Staph aureus
(occ Aspergillus or Candida but is rare)
**only swab in severe cases or if unresponsive to tx
What is first line therapy for mild-moderate acute otitis externa?
Topical antibiotic with or without topical steroids for 7-10 days
NSAIDs/Tylenol for pain control
TREATMENT
1- polysporin plus pain relief ear drops (polymyxin B sulphate-lidocaine) 3-4 drops qid
2-polysporin eye/ear drops 1-2 drops aid
3- ciprodex - ciprofloxacin with dex - 4 drops qid
What do you treat severe acute otitis externa with?
systemic antibiotics that cover Staph aureus and Pseudomonas
What can you do if cannot see ear canal in a pt with suspected Acute Otitis Externa?
Place an expandable wick to decrease canal deem and facilitate topical medication delivery
When should you expect to see a response and when do you reach full response for treatment of acute otitis externa?
response in 48-72 hrs
Full response in 6 days
What do you need to consider if no response to treatment for acute otitis externa?
obstruction
foreign body
noncompliance
alternate diagnosis
What is malignant otitis externa, how does it present, who is at risk for it and how do you treat it?
- invasive infection of cartilage and bone of canal and external ear
- facial nerve palsy and pain
- immunodeficient and insulin-dependent diabetics
- aggressive debridement and systemic antibiotics targeting Pseudomonas and aspergillus
When should you not use gentamicin, neomycin, agents with low pH or cortisporin (neomycin with polymyxin with hydrocortisone) in acute otitis externa?
- if tympanostomy tubes present
- if perforated TM
- if cannot see TM
**concern is due to ototoxicity
What is more common due to blood products: risk of infection or TRALI/anaphylaxis?
TRALI and major allergic or anaphylactic reactions
What are the steps to prevent infections from blood transfusion?
1) carefully assess if the pt needs the blood product (restrictive transfusion policies)
2) evidence-based effective policies for donor selection, screening, product collection, testing and infusion
What are the factors that increase the probability of infection in the recipient of blood product?
- prevalence of the agent in the blood donor population
- tolerance of agent to blood handling, storage
- infectivity and pathogenicity of the agent
- recipients health/immune status
- effectiveness of donor screening/testing
- effectiveness of aseptic techniques (for collection and infusion of the product)
What specific steps do we do in Canada to decrease infection risk of blood transfusions?
- collect blood from volunteer, unpaid donors
- donor interview and selection protocols
- aseptic techniques for collection and infusion
- diversion of the first 40 mL of blood (that blood not used)
- donor screening by serologic and other tests including bacterial detection in platelets
- viral inactivation in plasma-derived products
- leukocyte reduction techniques to decreased transmission of CMV
What viral inactivation procedures exist for blood products; what viruses do they target and for which blood products can they be used?
1) inactivation by heat, solvent/detergent, ultrafiltration and leukocyte depletion
2) CMV, HAB, ABV, ACV, HIV, West nile, Parvo B19, HTLB type I/II
3) only for plasma-derived blood products (NOT RBC or platelets)
What are some examples of plasma derived blood products?
albumin
IVIG
factor concentrates
Are all factors derived from blood products?
No. Majority of Factor VIII and IX in Canada are recombinant products and so not derived from plasma so does not have infectious risk of blood products.
Which has a higher infectious risk and why: platelets or RBC?
platelets b/c are stored at room temperature
What bacterial agents are responsible for acute infection during transfusion for each of the following: RBC, WBC, Plt, Plasma?
1) RBC - Yersinia enterolitica, gram-neg, pseudomonas
2) WBC - gram-neg org, pseudomonas
3) Plt - skin flora, Salmonella, E coli, Enterococci, Clostridium, Serratia marcescens
4) Plasma - Staph aureus, pseudomonas
What is the risk of death per unit of blood product transfused? What is the risk of an adverse event per unit of blood product transfused?
What is the risk of bacterial contamination?
Risk of death: 1 in 130,122
Risk of adverse event: 1 in 2950
Risk of bacterial contamination: 1 in 292,775
What are the 4 most common reactions reported with transfusion of blood products?
1) transfusion-associated circulatory overload (46%)
2) severe/anaphylactic/anaphylactoid rxn (16%)
3) hypotensive rxn (12%)
4) Transfusion-related acute lung injury (8%)
What are important elements of documentation related to blood transfusions?
Ensure pts are aware they received blood products
Document on discharge or outpatient note
hospital blood banks should have documentation
What is the risk of the following with transfusion of blood products:
1) HIV
2) Hep C
3) Hep B
4) bacteria
5) Parvo B19
1) HIV 1 in 8-12 million
2) Hep C 1 in 5-7 million
3) Hep B 1 in 1.1-1.7 million
4) bacteria apheresis plts 1 in 105,000; platelet pools 1 in 47,000
5) Parvo B19 1 in 5000-20,000
**risk of infection in plasma derived products is
What are cytokines?
Family of proteins that modulate the inflammatory process. Produced by monocytes, macrophages and T lymphocytes. Can be pro- or anti-inflammatory cytokines.
Eg. include TNF-alpha, IL-1, IL-6
How to biologic response modifiers work?
Are either antibodies to pro inflammatory cytokines or proteins that target the cytokine receptor. Aim to decrease the inflammation to prevent destruction of tissues.
Often are given in combo with other immunosuppressants like MTX or steroids
How do biologic response modifiers increase risk of infection?
T cell mediated immune response important for destruction of cells that harbour intracellular pathogens, form granulomas and ensure adequate cell-mediated immune response. BRMs decrease the cytokine response so at risk for reactivation of infections that were previously controlled or get inadequate response to new pathogens.
What infections are patients taking biologic response modifiers at increased risk of? How long does that risk persist?
TB
Mycobacteria (e.g. leprosy, non-tuberculous mycobacteria)
Molds or endemic fungi (eg Hisoplasma, blastomyces, )
Listeria
reactivating chronic viral infections (eg HSV) - case reports
(NO increased risk of typical bacteria like strep)
risk of infection related to length of treatment
increased risk of infection for weeks and possibly months after stopping the BRM.
What infectious patient work up should be done before starting biologic response modifier?
TST or blood-based assay for TB (IGRA if >5 yrs)
CXR
Consider serology for Histoplasma, Toxoplasma and other intracellular pathogens
Consider serology for Hep B, varicella and EBV
What counselling for infection avoidance would you give a pt about to start a biologic response modifier?
1) avoid undercooked meats, raw eggs or unpasteurized milk
2) avoid direct contact with soil or kitty litter (for Toxo)
3) avoid kittens (Bartonella)
4) avoid pet reptiles (Salmonella)
5) avoid pet bites or scratches (Pasteurella)
6) avoid construction sites, farmyard barns, cave exploration (fungal spores)
What vaccine related issues do you need to consider before starting biologic response modifier?
1) document vaccine status for inactive and live vaccines
2) counsel household members about risk of disease and ensure vaccination of those ppl for varicella, flu etc
How do you manage a patient whose vaccine status is not up to date for inactivated vaccines in a patient about to start biologic response modifiers?
Administer inactivated vaccines 14 days or more before starting BRM.
If pt on high dose steroids give vaccines 1 month before starting BRM.
Annual flu shot (not intranasal)
How do you manage a patient whose vaccine status is not up to date for live vaccines in a patient about to start biologic response modifiers?
Give 4 weeks or more before starting BRMs unless there is a contraindication (high-dose steroids or other immunosuppressive therapy).
In a pt about to start biologic response modifiers who needs TST and MMR when can these be done in relation to one another?
TST and MMR can be done on the same day.
If MMR given alone, need to wait 4-6 weeks before doing TST b/c MMR vaccine suppresses the response.
In pt about to start biologic response modifiers, who is
Consider dose of pneumococcal polysaccharide vaccine (Pneum -23 valent) at least 8 weeks after the last dose of pneumococcal conjugate vaccine. (Must be 24 months at least.)
How much has the pneumococcal conjugate vaccine (Preener) decreased radiologically proven pneumonia hospitalization rates in kids
By 27%
What makes a pneumonia complicated?
empyema (pus in pleural space)
lung abscess
necortic portion
What is the most common cause of pneumonia?
viruses (ex RSV, flu, parainfluenza, HPMV)
What are the most common bacterial causes of pneumonia?
Strep pneumo (most common) GAS Staph aureus HiB (almost disappeared) Mycoplasma pneumoniae (school age) Chlamydophila pneumoniae (school age)
How does pneumonia present in children?
fever cough WOB poor feeding vomiting chest pain abdo pain
What features suggest atypical pneumonia?
- malaise and headache for 7-10 days prior to onset of fever and cough
- bilateral focal or interstitial infiltrates (nonlobar)
- prominent cough
- minimal leukocytosis
What is the cut off for tachypnea in age 5 yrs?
60 breaths per minute
2-12 months - >50
1-5 yrs - >40
>5 yrs - > 30
What physical signs suggest a pnuemonic consolidation?
dullness to percussion
increased tactile fremitus
reduced normal vesicular breath sounds
increased bronchial breath sounds
What physical signs suggest a pleural effusion?
dullness to percussion
decreased tactile fremitus
decreased or absent breath sounds
When does a child require CXR to confirm a diagnosis of pneumonia?
Always preferable to have a CXR (2 views).
If highly suspected diagnosis but not ill enough to need hospitalization then does not need CXR.
How does a typical pneumonia present on CXR?
- consolidation - lobar with air bronchograms
- subsegmental or nodular opacities/infiltrates (round pneumonia)
When do you need to consider draining a pleural effusion?
large
clinically important cause of rest compromise
when response to therapy is not satisfactory
What testing should be done before starting antibiotics in a child who will be hospitalized for pneumonia?
- sputum and gram stain if age >10 yrs
- viral aspirate
- CBC
- blood culture (unusual to be bacteremic but still imp)
- CXR
When should you consider hospitalization in a child with pneumonia?
- poor PO intake
- severe illness
- severe resp compromise
- complicated pneumonia
- lower threshold for kids
What is the primary goal of abx treatment in pneumonia?
Good coverage for Strep pneumo
What is the treatment for outpatient pneumonia?
Amoxicillin 40-90 mg/kg/day PO div tid (max 4g/day) for 7-10 days
What is the treatment for inpatient uncomplicated pneumonia?
Ampicillin 200mg/kg/day IV div q6h (max 2g/dose) for 7-10 days total (incl step-down to PO)
What is the treatment for severe or complicated pneumonia?
Ceftriaxone 50-100mg/kg/day IV div q12h or q24h
-if empyema, lung abscess may need longer therapy usually 2-4 wks
-may need to add vancomycin if rapidly progressing for MRSA coverage
What is the treatment for atypical pneumonia? What is an alternate treatment?
Azithromycin 10mg/kg PO x1 on day 1, then 5mg/kg on days 2-5 (max 500mg/day)
Alternate is Doxycycline for kids > 8 yrs
What antibiotic should you use in pts with pneumonia who have a history of rash after penicillin?
If nonuriticarial rash can give them Ampicillin or Amoxil
If suspicion for anaphylaxis, give 2nd or 3rd generation cephalosporin but observe the 1st dose for 30 mins and have epi available. Can also use Clarithro or Azithro but increasing resistance to these.
If history of SJS need to pick diff abx class.
When should you repeat a CXR or chest US in a patient with pneumonia?
If no improvement within 48-72 hrs of starting antibiotics.
What are reasons/DDx a child with pneumonia may not be improving after 48-72 hrs of antibiotics?
- complication with empyema, abscess
- foreign body
- reactive airways disease with atelectasis
- congenital pulmonary anomaly
- TB
- unrecognized immunodeficiency with opportunistic infection
How long does it take for radiographic resolution of a pneumonia?
4-6 weeks
do NOT repeat a CXR at the end of therapy
For what conditions did introduction of the seven-talent pneumococcal conjugate vaccine (Prevnar, PCV7) cause improvements? Any drawbacks to its introduction?
- near eradication of invasive pneumococcal disease
- pneumococcal meningitis
- reduction in hospitalization for pneumonia
- reduction in AOM and type placement
DRAWBACKS - increase in non-vaccine serotypes (esp serotype 19A) but some of these are covered with Prevnar13 (incl 19A)
What is the recommended schedule for the 7-valent pneumococcal conjugate vaccine (PCV7)?
Seems 3 dose schedule (2 in infancy and one in the 2nd yr of life) as effective as a 4 dose schedule (3 in infancy and one in 2nd year of life).
**high risk kids given the 4 dose schedule
What pneumococcal vaccine do we use in Ontario and what is the schedule?
PCV13 (13-valent pneumococcal conjugate vaccine)
Recommend a 4 dose schedule (3 in infancy and one in 2nd year of life)
**ontario currently giving a 3 dose schedule
What is the recommendation for pneumococcal vaccine in kids 12-35 months?
- all should get PCV13
- high risk for IPD should get 23-valent polysaccharide pneumococcal vaccine after age 2 yrs (Pneu-P-23)
What precautions should you tell families to protect against biting insects like ticks and mosquitos?
avoid exposure
use physical barriers
use chemical barriers
What avoidance tactics can you tell families to avoid ticks/mosquitos?
- avoid being outside at dusk and dawn
- avoid standing water
- tall grasses are where ticks breed
What physical barriers can families use to avoid ticks/mosquitoes?
- screens on windows/doors
- cover crib, playpen, stroller with fine mesh
- dress kid in long, loose-fitting clothes that cover arms and legs, wear closed shoes
- light colours make ticks easier to see and do not attract mosquitos as much as dark clothes
How do you remove a tick?
- inspect daily if in endemic area
- use fine-tipped tweezers and grab tick close to skin surface
- pull upward with steady, even pressure (do NOT twist)
- if mouth part breaks off and you cannot remove it easily then leave it alone and let it heal
- clean the bite area and hands with alcohol, iodine scrub or soap and water
- put tick in clean container and contact public health unit
What is the difference between a repellent and an insecticide?
Repellant – prevent blood-feeding insects from landing and biting
Insecticide – kill insects and ticks on contact or soon after
What are the common active ingredients in repellents in Canada?
1) DEET
2) icaridin
3) biopesticides (derived from natural materials like oil of lemon eucalyptus)
What are the recommendations for use of DEET-containing repellents in kids
12 yrs
- 30% DEET
- protection time is 5-8 hours
What are side effects from DEET repellent?
contact dermatitis
eye irritation
What are the recommendations about Icaridin as repellent?
first choice by public health for kids 6 months - 12 yrs
safe to use products containing up to 20% icaridin
At what age can kids start using repellent?
over the age of 6 months
What are the options for “natural” repellent or biopesticides?
- use products that have PMD in it (p-menthane 3,8-diol) but must be 3yrs or older
- oil of lemon eucalyptus
- 2% soybean oil can protect against mosquitoes for 3.5 hrs
What are recommendations to parents on how to apply/use repellents?
- avoid products with combo repellent and sunscreen
- apply sunscreen first, wait 20 mins then apply repellent
- apply product lightly
- avoid repellent on a child’s hands, mouth or eyes
- if spray and get in the eyes riches with water right away
- do not put repellent on sunburnt or wounded skin
- do not put on under clothes
- do not put repellent on anything the kid might chew on
- remove kid from area where mosquitoes are biting
- wash off repellent with soap and water when done for the day
- spray repellents in open ventilated areas
- store repellent away from reach of kids
What is the role of permethrin for mosquito and tick prevention?
- is an insecticide and repellent
- NOT to be used topically
- can be sprayed on clothes, bed nets,
- can retain effect for up to 2 weeks or 6 washings
- many products marketed as protective are not recommended b/c not enough evidence
What are the most common serogroups that cause invasive meningococcal disease?
A B C Y W
Which meningococcal serotype is the most prevalent and in which age group do the majority of cases occur?
serotype B
in pre-school kids
What vaccine do we have for MenB?
4-component vaccine called 4CMenB or Bexsero; could not use a polysaccharide vaccine b/c does not elicit a response to it.
Not all strains of MenB express the components in the 4CMenB vaccine
What are the number of required doses of 4CMenB?
-vaccination at 2, 4 and 6 months but likely that boosters will be required
What is the most common side effect of the 4CMenB vaccine? How do you treat it?
Fever.
Can give antipyretics without dampening immune response to vaccine.
What is the morbidity and mortality of MenB?
70% of cases occur in the first year of life
Mortality is 3.8% in kids
Who should receive the MenB vaccine?
- pts with asplenia or hyposplenia
- congenital complement deficiency
- factor D or properdin deficiencies
- primary antibody deficiencies
- anyone with a history of more than one episode of invasive meningococcal disease
- lab personnel who work with the organism
From what 3 sources is a patient undergoing organ transplant at risk of acquire infection?
1) endogenous reactivation of latent pathogens (e.g. herpes)
2) transmission from the donated organ or tissue
3) transmission from the community or health care setting
When preparing a patient for organ transplant what vaccination considerations do you have to think about? Which vaccines to give and when in relation to the transplant?
- optimize vaccine status (ideally before immune suppression)
- give inactivated vaccine at least 2 wks before the transplant
- minimum of 4 weeks btw live vaccine and onset of immune suppression
- live vaccines contraindicated after transplant
- household contacts should be up to date with their vaccines
What should you expect in terms of infection in the first month post transplant?
->95% of infections are similar to infections of nonimmunosuppressed people who had surgery
What should you expect in terms of infection in months 1-6 post transplant? Which bugs?
- risk of viral pathogens - (EBV, CMV, hep B, hep C); can be primary infection or reactivation or reinfection
- risk of other pathogens: Listeria, Aspergillus, Pneumocystis jirovecii
What is the infection profile of patients > 6 months post transplant?
-if on maintenance immunosuprression and good allograft function are likely to get same infections as healthy kids (common respiratory viruses)
What work up should you do in a febrile transplant patient with a clear focus of infection?
- CBC, BCx at minimum
- admission depending clinical status
What work up should you do in a febrile transplant pt who has a normal exam and no focus of infection?
- admit if unwell
- CBC, BCx, UCx, consider viral aetiologies like CMV and EBV
- consult with transplant team about antibiotics as can interact with immunosuppressants
When can you give a post-transplant patient vaccines?
- usually not for the first 6-12 months
- can give inactivated flu vaccine at least one month post-transplant
- live vaccines contraindicated
What are the recommendations for pneumococcal and meningococcal vaccines in transplant patients?
- highrisk for invasive pneumococcal disease, esp heart transplant pts
- give Prevnar 13 (13-valent pneumococcal conjugate) followed in 8 wks by the 23-valent vaccine
- give meningococcal vaccines as per routine schedules but give meningococcal conjugate quadrivalent vaccine (MCV) rather than the polysaccharide quadrivalent vaccine
- need to be at least 2 yrs for the conjugate quadrivalent
Can you give a post-transplant pt the HPV vaccine?
Yes. Strongly recommended to give for both males and females post transplant b/c increased risk of developing severe genital warts.
Any specific recommendations for Hep A and Hep B vaccines post-transplant?
Hep A - if have risk factors (e.g. liver disease, travel)
Hep B - as per routine schedule but with double the dose
What counselling should you give a post-transplant patient about risk of infection with daily living activities?
- food and drinking water
- pets
- animals
- swimming
- fungal spores from gardens, farms, constructions sites,
- mosquitoes
- travel
- sexual behaviour
What prophylaxis and for how long do you give to post-transplant patients for:
1) HSV
2) CMV
3) EBV
4) Candida
5) Aspergillus
6) PJP
7) Toxo
1) HSV - acyclovir x 3 months
2) CMV - IV ganciclovir for 3 months
3) EBV - no established regimen, ganciclovir in some
4) Candida - fluconazole and ample B selectively for up to 4 weeks
5) Aspergillus - voriconazole, itraconazole - for 4-6 months
6) PJP - TMP-SMX for 6-12 months
7) Toxo - pyrimethamine/sulfadiazine for 6 months
What are the main side effects of Rituximab?
infusion related reactions (fever, chills, hypotension)
angioedema
pancytopenia
What are the main side effects of Cyclosporin (calcineurin inhibitor)?
- hirsutism
- gingival hyperplasia
- nephrotoxicity
- HTN
What are the main side effects of Tacrolimus (calcineurin inhibitor)?
- tremor
- dose-dependent neuropathy
- nephrotoxicity
- HTN
- hyperglycemia
What are the main side effects of Imuran (Azathioprine)?
leukopenia
anemia
thrombocytopenia
Which drugs are cytochrome P450 inducers (decrease levels of immunosuppressants)?
- rifampin
- rifabutin
- caspofungin (only with tacrolimus)
- nevirapine
- efavirenz
Which drugs are cytochrome P450 inhibitors (increase levels of immunosuppressants)?
- azithro
- clarithro
- erythro
- flagyl
- levofloxacin
- cipro
- fluconazole
- keoconazole
- itraconazole
- variconazole
- indinavir, nelfinavir (bunch of antivirals)
What are the important steps in working with vaccine hesitant parents?
1) Understand the specific vaccine concerns.
2) Stay on message and use clear language to present evidence of benefits and risk
3) Inform parents about rigour of vaccine safety system
4) Address the issues of pain with immunization
5) Do not dismiss children from your practice b/c parents refuse to immunize
What strategies can you use to help understand the specific vaccine concerns of vaccine-hesitant parents?
- nonjudgemental, nonconfrontational
- ask parents to describe their understanding of risks and benefits
- do not bring up concerns parents themselves have not brought up
- can relate compelling stories of children killed by vaccine preventable diseases
What can you say to parents who are vaccine-hesitant about the consequences for others, herd protection, wait-and-see and vaccinate only in outbreak?
Consequences for others: can infect sibling with pertussis, pregnant women with rubella, grandparent with the flu, coccoon infants by immunizing those around them
Herd protection: not possible for all diseases, e.g. tetanus is in the soil
Wait and see: full protection against many disease cannot be achieved by only one dose of the vaccine so may take 2-3 weeks after vaccine to have protective antibodies
What can you tell vaccine hesitant parents about the rigour of our vaccine safety system?
- vaccines held to higher safety standard than drugs
- NACI and CPS make recommendations
- statements made are independent of manufacturers
- many vaccines approved in Canada are first used in other countries of a while so we benefit from additional knowledge of safety and effectiveness
What can you do to alleviate fears about pain associated with vaccination?
reassurance
distraction
clinical practice guideline on reducing pain during vaccination
What are risk factors associated with the spread of community-acquired MRSA?
- close skin to skin contact
- cuts or abrasions to the skin
- contaminated items/surfaces
- crowded living conditions
- poor hygiene
What are the invasive complications of MRSA?
- osteomyelitis
- septic arthritis
- nec fasciitis
- sepsis
- pneumonia
What is the general recommended management of CA-MRSA skin abscesses?
-most can be managed with drainage alone and no abx
What are the indications for treatment of abscess with abx (even if suspect MRSA) in kids?
-age
Which antibiotics cover MRSA - which would you use in an outpatient setting and why or why not?
- TMP/SMX - first line choice (down side is poor coverage for GAS)
- Doxycycline - kids > 8 yrs, must be able to swallow pills,
- Clindamycin - tastes terrible, increasing resistance, increased risk of C diff
- Linezolid - $$$$$$$$$$$$
Which antibiotics would you choose to cover for an abscess that you suspect could be MRSA and/or GAS?
-TMP/SMX and cephalexin (for the GAS coverage)
What are the indications for decolonization of a family for MRSA?
-we do not decolonize b/c failure is common
How would you manage a child
-admit and treat with IV abx (usually vancomycin)
How would you manage a child 1-3 mo with no fever, no systemic illness but a skin abscess after it was drained?
-TMP/SMX PO (controversial to give this to kids
How would you manage a kid age >3 mo with low-grade fever (
- observe after drainage
- abx only if does not improve or culture grows something other than staph aureus
How would you manage a kid >3 mo old with a skin abscess that was drained with low grade fever, significant surrounding cellulitis but systemically well?
TMP-SMX and cephalexin PO pending cultures
Amphotericin B: in what forms is it available, what are the major side effects, what is it used for?
- IV
- nephrotoxicity, infusion-related events (fevers, chills),
- broad spectrum anti fungal
- some aspergillum, candida
Fluconazole: in what forms is it available, what are the major side effects, what is it used for?
-PO and IV
-readily penetrates into tissues b/c low lipophilic nature
-hepatotoxicity, inducer of cytochrome P450
-Candida and cryptococcal infections, prophylactic agent in stem cell transplant pts
NO activity against Aspergillus and other moulds
Itraconazole: in what forms is it available, what are the major side effects, what is it used for?
- PO and IV
- GI intolerance, abdo pain, V/D, elevated liver enzymes, inhibits cytochrome P450
- prophylaxis against Candida and Aspergillus, used for severe Aspergillus infection or step-down
Voriconazole: in what forms is it available, what are the major side effects, what is it used for?
- PO and IV (do not use IV in pts with renal problems)
- skin rash, visual abnormalities, photosensitivity reaction, elevated hepatic transaminase or serum bill
- invasive Aspergillus, Candida
Posaconazole: in what forms is it available, what are the major side effects, what is it used for?
- PO
- used for Candida and Aspergillus
- salvage therapy when other first line agents have failedR
Ravuconazole: in what forms is it available, what are the major side effects, what is it used for?
- PO and IV
- good for Candida, Aspergillus, Cryptococcus, Hisoplasma, Coccidioides
What are echinocandins? Name 2. What are they used for?
- glucan snythesis inhibitors that compromise integrity of fungal cell wall
- only available as iV
- caspofungin and Micafungin
- used for invasive candidiasis and aspergillosis
What is flucytosine, what are the side effects and what is it used for?
- PO antifungal antimetabolite
- SE: GI intolerance, bone marrow suppression, rash, hepatotoxicity, headache, confusion, hallucinations, sedation, euphoria
- used in combo with ampho B for Candida or crytpococcus esp if CNS involvement
When should you use antifungals in combination?
- for crytococcal meningitis
- many experts say also for CNS fungal infections, incomplete response to initial therapy, where optimal dosing is compromised due to toxicity
What antifungals are effective against aspergillus?
- voriconazole
- posaconazole
- echinocandins (eg caspofungin)
- some ampho B
What are the indications for the TB skin test in kids?
- contacts of known cases of active TB
- children with suspected active TB disease
- known RF for progression of infection to disease
- kids travelling or living for 3 months or more in an area with a high incidence of TB
- kids who arrived from countries with high TB incidence in the past 2 years
What are causes of false negatives (poor sensitivity) of the TB skin test in kids?
- very young age
- infant
What are causes of false-positives (poor specificity) of the TB skin test?
- previously vaccinated with BCG vaccine
- infected with environmental nontuberculous mycobacteria
What are some general drawbacks of the TB skin test?
- poor standardization
- inter/intra observer variability
- requires 2 visits (one to come back to be read)
What is an IGRA?
interferon-gamma-release-assay
-measures in vitro production of interferon-gamma by sensitized lymphocytes in response to M. tuberculosis
Which is more specific the TST or the IGRA?
IGRA
What is a benefit of the IGRA over TST?
-only requires one visit
What are the Red Book recommendations for IGRA use?
-not to be used in kids
What does the Canadian TB committee say about using IGRA?
-useful in outbreak settings in which population to be screed may be low risk but have false positive skin tests due to BCG (test with TST or both TST + IGRA)
How should you screen for latent TB infection in immunocompromised children? What do you do with the results?
- start with TST
- if TST positive = LTBI and should be treated
- if TST negative but high suspcion of TB then do IGRA (b/c high rate of false neg TST in immunocompromised)
Can you use TST alone to make dx of TB disease? Can you use IGRA alone? If TST and IGRA are negative is TB ruled out?
- always ideally want cultures
- TST yes
- IGRA never used in isolation
- negative IGRA and TST does not R/O active TB in all ages
What are the RF for development of active TB in ppl infected with M tuberculosis ?
- -AIDS
- HIV
- transplant
- silicosis
- CRF needing hemodialysis
- carcinoma of head and neck
- recent TB infection (within past 2 yrs)
- abnormal CXR - granuloma or fibronodular disease
- tx with steroids, TNF-alpha
- having diabetes (any type)
- underweight
- young age when infected (Age
Why do we treat patients with positive TST?
-much higher risk of TB disease in TST positive individuals and they get benefit from ionized prophylaxis
What should you do in the management of an HIV-exposed or HIV-infected child?
-consult peds ID with expertise in HIV
What are RF for invasive group A strep in adults? What additional RF are there in kids?
- HIV
- heart disease
- diabetes
- lung disease
- alcohol abuse
- IVDU
- pregnancy-related factors
In kids: young age, varicella
What must you do if you confirm a case of invasive GAS?
report to public health
How do you confirm a case of invasive GAS (Strep pyogenes?
-lab confirmation via isolation of GAS from a normally sterile site
What are the criteria for invasive GAS disease?
(1) strep toxic shock with hypotension and 2 of:
a. renal impairement
b. coagulopathy (plt 2x ULN)
d. ARDS
e. generalized erythematous macular rash that may desquamate
(2) soft-tissue necrosis including nec fasciitis, myositis, gangrene
(3) meningitis
(4) combo of above
What is considered a severe case of invasive GAS?
- toxic shock syndrome
- soft-tissue necrosis (myositis, nec fasc, gangrene)
- meningitis
- GAS pneumonia
- other life-threatening or death-causing conditions
What is the definition of close contacts for invasive GAS disease?
- household contacts who spend 4h/day or 20 h in past week with the pt
- nonhousehold contacts who share bed or had sex with pt
- person with direct mucous membrane contact of oral or nasal secretions
- IVDU who shared needles
- some contacts in old folks homes, daycares, hospitals
Who needs prophylaxis for invasive GAS ?
- only give to close contacts of confirmed case of SEVERE invasive GAS if exposed in the 7 days before onset of symptoms up to the 24 hrs after abx started
- give asap but up to 7 days after last contact with pt
- do NOT need prophylaxis for GAS bacteria or septic arthritis contacts
- do not need cultures for contacts
What are the first and second line agents for chemoprophylaxis of severe invasive GAS disease?
1) 1st gen cephalosporin: 25-50mg/kg div bid-qid x 10 days
2) Macrolide: eg. Erythromycin 10-15 mg/kg bid x 10 days
3) clindamycin
What is the first line treatment of invasive GAS disease?
Penicillin + Clindamycin
IVIG in some cases of Toxic shock or severe toxin-mediated disease
Why were the prophylaxis for infective endocarditis guidelines revised in 2007 (4 reasons)?
1) IE more likely from flossing, brushing, chewing than dental, GI or GU procedures
2) prophylaxis prevents exceedingly small number of cases of IE
3) risk of abx associated adverse events exceeded the benefits in most cases
4) maintenance of optimal oral health is more important than antibiotics prophylaxis
Who should receive antibiotic prophylaxis for infective endocarditis?
1) prosthetic cardiac valve or prosthetic material used for valve repair
2) previous IE
3) unrepaired CHD including shunts and conduits
4) completely repaired CHD with prosthetic material or devise during 1st 6 months after procedure
5) repaired CHD with residual defects at site or adjacent to site of prosthetic patch or devise
6) Cardiac transplant pts with valvulopathy
List examples of conditions for which antibiotic prophylaxis for IE is NOT indicated.
- ASD
- VSD
- PDA
- MVP
- hx Kawasaki
- hypertrophic cardiomyopathy
- previous coronary artery by pass
- cardiac pacemakers
- bicuspid aortic valve
- coarc
- calcified aortic stenosis
- pulmonic stenosis
Why do repaired CHD with prosthetic material only need prophylaxis during 1st 6 months after procedure?
-to allow for endothelialization of the prosthetic material
For which procedures is antibiotic prophylaxis for infective endocarditis indicated?
1) dental procedures that involve the manipulation of gingival tissue, periodical region of teeth or perforation of oral mucosa
2) respiratory tract procedures that involve incision or bx of rest mucosa (e.g T+A)
NOT for GI or GU procedures, not for orthodontic procedures, teeth XRs etc
What is 1st, 2nd, 3rd line (PO and IV) including doses for prophylaxis for infective endocarditis? When should it be given
Give ideally 30-60 mins before procedure but can be up to 2 hrs after. All as only single dose
1) Amoxil 50 mg/kg or Amp 50mg/kg IV
2) Cephalexin 50mg/kg or Cefazolin 50 mg/kg IV
3) Azithro or Clarithro 15 mg/kg
4) Clindamycin 20 mg/kg
What are the 8 components of the Canadian vaccine safety system?
1) prelicensure review and approval - studies in ppl
2) current good manufacturing practices - plant standards, govt random inspections
3) lot assessment before release - each lot tested (not done for drugs)
4) independent expert review of national vaccine recommendations (NACI)
5) post-marketing surveillance for adverse events - for detection of the super rare adverse events; also have active surveillance look at cases of vaccine-preventable illness admitted to hospital
6) rapid response to vaccine performance concerns - rapidly will pull a vaccine if any concerns
7) expert causality assessment of serious adverse events following immunization
8) international collaboration
What do you do if there is a serious adverse event following immunization?
-are required to report using standardized reporting form to Canadian Adverse Events Following Immunization Surveillance System (CAEFISS) via public health
How does influenza usually present in children? How is it different in infants?
- in kids: fever, cough, rhinorrhea, resp distress
- in kids
Why don’t we give the influenza vaccine to kids
-poor immunogenicity
What are the 2 recommended strategies to prevent influenza in kids
- vaccinate pregnant women
- immunize caregivers and family of the young infant
What are the benefits of vaccinating pregnant mum’s against influenza?
- maternal influenza antibodies passed to baby before birth
- maternal antibodies passed via breast milk
-relative risk reduction in influenza-proven cases in young infants if pregnant mum is vaccinated is 64% (NNT is 17)
What are the side effects of the influenza vaccine for pregnant mums?
-none. Is safe. No teratogenic effects. Killed vaccine so cannot replicate or cause the flu.
How is syphilis acquired?
- vaginal, anal or oral sex with a person infected within the last year
- vertical transmission
- kissing, transfusion, needle sharing, direct contact with infected lesion are rare
What are the signs and symptoms of syphilis in adults and what does this mean for pregnant women and screening?
- many have no distinctive clinical manifestation
- all pregnant women should be assumed to be at risk
- screen all pregnant women at the first prenatal visit, prescreen at 28-32 weeks and at delivery in high-risk women
- do not discharge a newborn from hospital unless have seen negative syphilis serology from mum
What is the risk of vertical transmission with untreated primary or secondary syphilis? early latest? late latent?
untreated primary or secondary syphilis: - 70-100%
early latent: - 40%
late latent: -
What testing do we do for syphilis?
- most places do RPR titre as initial screen and confirm a reactive result with a treponemal test (e.g. fluorescent treponema antibody absorption FT-ABS)
- some places do enzyme immunoassay (EIA) as initial test and confirm with treponemal test
How long does the treponema test stay reactive for after having syphilis?
for life
What is the expected decrease in RPR titres in adequately treated syphilis for primary? secondary? early latent?
Primary: fourfold drop at 6 mo, 8-fold at 12 mo, 16-fold at 24 mo
Secondary: 8-fold drop at 6 mo, 16-fold drop at 12 mo
Early latent: 4-fold drop at 12 mo
What do you do with a women who has a reactive treponema test, nonreactive RPR during pregnancy, no hx of treatment and no evidence of early primary syphilis?
- treat for late latent syphilis
- assume there is a risk of vertical transmission
What is early congenital syphilis?
- syphilis dx in the first 2 years old life
- often are asymptomatic at birth
What investigations can you do in an infant you suspect might have syphilis?
- RPR titres, confirmatory assay with treponemal test
- examine skin lesions, nasal discharge, placental lesions or umbilical cord for treponemes
What are the features (S+S) of congenital syphilis?
- spontaneous abortion/stillbirth/hydrops fetalis
- necortizing funisitis (umbilical cord looks like “barbershop pole”)
- rhinitis/snuffles
- rash (diffuse maculopapular, can have other appearance)
- hepatomegaly, splenomegaly
- lymphadenopathy
- neurosyphilis
- MSK involvement (osteocondritis or paerichondritis on XR, later pseudo paralysis, frontal bossing, poorly developed maxillas, saddle nose, winged scapulas, sabre shins)
- heme abnormalities (anemia, thrombocytopenia)
- interstitial keratitis
- Hutchinson’s teeth (upper central and lateral incisors widely spaced and shaped like screwdrivers)
- mulberry molars (dwarfing of the cusps, hypertrophy of enamel, looks like a berry)
- 8th nerve deafness (sensory neurodeafness)
What is the management of infant born to mum treated for primary, secondary or early latent syphilis during pregnancy more than 4 weeks before delivery, adequate fall in RPR titres and no evidence of relapse?
- baseline and monthly assessments for S+S of congenital syphilis for the first 3 months
- syphilis serological tests (RPR and trepenemal test) at 0, 3, 6 and 18 months
- NO long-bone radiographs
What is the management of infant born to mum treated for late latent syphilis anytime during or following the pregnancy?
-syphilis serological tests (RPR and treponema test) at 0, 3, 6 and 18 months
What is the management of infant born to mum with untreated primary or secondary syphilis during pregnancy, infants RPR 4x greater than mums, treponemes detected from infant, rising infant titre, any findings of congenital syphilis or has reactive RPR and trepenemal test at age 12 months or reactive treponemal test at 18 months?
- -baseline and monthly assessments for S+S of congenital syphilis for the first 3 months
- syphilis serological tests (RPR and trepenemal test) at 0, 3, 6 and 18 months
- needs long bone XR
- CBC
- CSF including for VDRL
- low threshold for ophtho and audiology assessments
- treat for congenital syphilis
What is the management of infant born to mum with treated for primary, secondary or early latent syphilis within 4 weeks of delivery or treated with an antibiotic other than penicillin, or mum was treated and RPR did not show expected decline or inadequate time has passed to assess the decline?
- -baseline and monthly assessments for S+S of congenital syphilis for the first 3 months
- syphilis serological tests (RPR and trepenemal test) at 0, 3, 6 and 18 months if treated
- if not treated do tests at 0, 1, 2, 3, 6, 12 and 18 mo
- needs long bone XR
- CBC
- CSF including for VDRL
- low threshold for ophtho and audiology assessments
- usually treat for congenital syphilis
What is the management of infant born to mum with treated for primary, secondary or early latent syphilis before pregnancy but there are doubts about adequacy of therapy or possibility of reinfection or mum treated for primary, secondary or early latest syphilis before or during the pregnancy and her f/u RPR was not obtained or mum was treated for any type of syphilis during pregnancy but long-term infant follow up cannot be assured?
- -baseline and monthly assessments for S+S of congenital syphilis for the first 3 months
- syphilis serological tests (RPR and trepenemal test) at 0, 3, 6 and 18 months if treated
- if not treated do tests at 0, 1, 2, 3, 6, 12 and 18 mo
- Mandatory to do the following if mother had primary, secondary or early latent syphilis and f/u unlikely or abnormal serology:
- long bone XR
- CBC
- CSF including for VDRL
- low threshold for ophtho and audiology assessments
- treatment dependent on risk
What is the management of an infant with a reactive RPR and treponemal testing at 6 months of age?
- long bone XR
- CBC
- CSF including for VDRL
- low threshold for ophtho and audiology assessments
- usually treat for congenital syphilis
How do you diagnose neurosyphilis and how often do you repeat the CSF?
- with VDRL testing of CSF (lacks sensitivity but if positive is diagnostic)
- if CSF abnormal obtain CSF q6months until normal
- low threshold to repeat treatment if CSF abnormalities persist at 6 months
What is the treatment of congenital syphilis?
10 days of crystalline penicillin G 50,000 units/kg q12 h if 4 wks old
Which foods are at increased risk of causing food borne infections?
- undercooked meat, poultry, seafood
- unpasteurized milk
- eggs (including intact eggs)
- fresh fruit and vegetables
- alfalfa sprouts
- unpasteurized fruit juices
What are risk factors for getting a food borne illness?
- using contaminated raw food supplies,
- improper food handling
- intentional consumption of raw or undercooked foods of animal origin
- preparation in bulk
- suboptimal storage or reheating practices
What are the major bugs you are at risk for from unpasteurized milk, cheese or dairy products?
- Salmonella
- Campylobacter
- E coli O157
- Listeria
- Mycobacterium bovis
- Brucella
What are the major bugs you are at risk for from unpasteurized fruit or vegetable juice?
- E coli O157
- Salmonella
- Clostridium botulinum
What are the major bugs you are at risk for from eggs?
Salmonella
What are the major bugs you are at risk for from raw or undercooked meat or poultry?
- Salmonella
- Campylobacter
- E coli O157
- Yersinia
- Listeria
- Toxoplasma
- Brucella
- Trichinosis
What are the major bugs you are at risk for from raw fish and shellfish?
- Vibrios
- Norovirus
- hep A
- many others
What are the major bugs you are at risk for from fresh fruits and vegetables?
- Cryptosporidium
- Cyclospora
- calcivirus
- norovirus
- Giardia
- Shigella
- E coli O157
- hep A
What are the major bugs you are at risk for from sprouts?
- salmonella
- E coli O157
- hep A
What are the major bugs you are at risk for from honey?
C botulinum
What are the major bugs you are at risk for from cream filled pastry, potato, egg or creamy salad dressing?
- Staph aureus
- Bacillus cereus
(eat immediately or store promptly in the fridge)
What are 10 rules for safe food preparation?
1) Choose foods that are sage
2) Separate food to be eaten raw from food to be cooked
3) careful hand washing before and after food prep
4) Cook meats, fish, etc thoroughly
5) Eat foods soon after they are cooked
6) store cooked foods appropriately
7) reheat cooked foods adequately
8) keep the kitchen meticulously clean
9) protect foods from insects, rodents, pets
10) always use safe water for food prep
What additional measures should you tell parents of immunocompromised children with regards to food preparation to prevent food borne illnesses?
-cook meats thoroughly and use a thermometer
-avoid meat pates or spreads
-be careful with any foods containing raw eggs
-soft cheese and cheese to which live microbial cultures have been added should be avoided
-fresh fruits and veggies need to be thoroughly washed
(avoid if cannot be washed properly, peeled or cooked)
-avoid raw seed sprouts
What is west nile virus, and what is its cycle and transmission?
- a flavivirus
- maintained in bird-mosquito transmission cycle
- virus becomes active in the spring, on birds which infects mosquitoes which then infect birds
- mosquitoes transmit it to people
- peak risk is late summer, early fall
Are blood products and organs for transplant screened for west nile virus?
yes
What are severe symptoms/presentations of west nile?
encephalitis
meningitis
tremor
flaccid paralysis
Does west nile virus have teratogenic effects?
infection of pregnant women with WNV is not uncommon but adverse events to infant are rare.
What are the most common fungal infections in infants and children?
mucocutaneous candidiasis pityriasis versicolor tinea corporis tinea pedis tinea capitus
When does oral thrush occur and what is a risk factor for it?
1) thrush can be seen as early as 7 days after birth
2) infant soother is a RF
What are pros/cons of different treatment options for thrush?
1) Topical gentician violet - can cause irritation, ulceration, stains, difficult clinical assessment
2) Nystatin suspension 200,000 units PO qid x 7-14 days
(give after feeds)
3) miconazole or clotrimazole (more effective than nystatin but not licensed in Canada)
4) Fluconazole, itraconazole if topical treatments fail (are more expensive)
When is Candida diaper dermatitis most commonly seen?
age 2-4 months
How do you treat Candida diaper dermatitis?
- decrease maceration of kin
- eliminate impervious diaper covers
- change diapers frequently
- leave diaper off for long periods
- need topical anti fungal
1) miconazole (monistat) 2% once or twice daily
2) nystatin cream or ointment 2-3 times daily
3) clotrimazole (canesten) 1% bid for 7 days (max 14 days)
- -unclear if should give concomitant PO and topical antifungals
What is pityriasis versicolor and how do you treat it?
Tinea versicolor
- mild or chronic condition characterized by scaly hypo or hyper pigmented lesions on the trunk
- treat with topical ketoconazole, selenium sulphide or clotrimazole
Eg. ketoconazole 2% shampoo or selenium sulfide 1% loction or 1% shampoo to affected area for 15-30 mins for 1-2 weeks then once a month for 3 months (to prevent recurrences)
What is Tinea corporis and how do you treat it?
Ringworm = superficial infection of skin that is not covered by hair
-circular
Treat with clotrimazole, ketoconazole, miconazole or terbinafine 1-2x/day for 14-21 days
What is tinea pedis and how do you treat it?
athlete’s foot = common in teens, fungal infection of foot
Treat with topical antifungals
- use drying agent (e.g. Burrow’s solution) as an adjunct
- treat with PO anti fungal if toenails involved
What is tinea captious and seborrheic dermatitis and cradle cap and how do you treat it?
- fungal infection of scalp, very common in meds
- cradle cap = pityriasis capitis
-cradle cap and seborrheic dermatitis usually revolves with mild soap application; shampoos with selenium sulphide or an azole if severe
What are some characteristics of fluconzole?
- activity against Candida
- hydrophilic so present mainly in boil fluids (not useful for superficial or skin fungal infections)
What are some characteristics of itraconazole?
- long half-life in skin and nails
- affinity for lipids and keratin
- can use it for tinea capitus
What are some characteristics of terbinafine?
- antifungal
- lipophilic and keratinophilic
- NOT metabolized via cytochrome P450 so less drug interactions
- side effects include GI and skin reactions, loss of taste (temporary)
- good for resistant superficial dermatophyte infections, nail infections, tinea pedis, tinea coporis, tinea cruris
Why was the 1998 report published by Andrew Wakefield linking MMR to autism disproven?
- causality interpretation was based on claims of parents of 8 kids studied who said their kids’ problems started within days of receiving the vaccine
- 5 of the kids studied were not neurologically normal prior to receiving the vaccine
- large population based studies have disproven and shown NO link btwn MMR and autism including Cochrane review
- 10 of the 13 authors have retreated their interpretation of the results
- study was never approved by ethics
What is thimerosal? What is it used for? Do we still use it in Canada? What are the side effects of thimerosal?
- compound that contains ethyl mercury
- used as an additive to vaccines to prevent bacterial contamination esp in opened, multidose vials
- no vaccine made in Canada since 2001 for routine use has used thimerosal with the exception of some Hep B and some flu shots (there are thimerosal-free flu vaccine preparations)
- NO side effects, is safe, no link to autism
What are contraindications to breastfeeding?
1) active TB unless have received 2 weeks of appropriate anti-TB treatment (can still feed expressed breastmilk)
2) Brucellosis
3) HSV if lesions on the breast/HSV mastitis until are crusted over (cover oral labial lesions with a mask)
4) HIV
5) Human T-cell lymphotrophic virus type I or II (expressed breast milk is also contraindicated)
Can a mum breastfeed if she has mastitis and breast abscess?
yes unless there is obvious pus in which case pump milk and discard it from infected breast and continue breastfeeding via other breast.
Can you breastfeed with malaria? Any precautions?
yes. Mum should not take quinine if baby has G6PD deficiency
Can you breastfeed with CMV if it is latent? active?
yes and yes
Which maternal medications are contraindicated in breastfeeding?
1) high-dose metronidazole (stop breastfeeding for 12-24 hrs)
2) chloramphenicol (can cause bone marrow suppression)
3) primaquine/quinine - contraindicated unless mum and baby have normal G6PD
What birds transmit West Nile Virus?
-Corvidae family: crows, jays, ravens, magpies
What are the common presenting symptoms of West Nile Virus? incubation period? how long does illness last?
Incubation: 3-14 days
Symptoms: many are asymptomatic, fever, headache, backache, myalgia, malaise, fatigue, arthralgia, GI sx, maculopapular rash, ocular pain, pharyngitis, conjunctivitis, lymphadenopathy, resp symptoms
Duration: 3-6 days
What are lab and CSF findings in West Nile Virus?
- CBC usually normal but may have anemia or lymphocytopenia
- CSF: mild pleocytosis, lymphocyte predominance, elevated protein, normal glucose
What is the treatment for West Nile Virus?
-supportive
How do you diagnose West Nile Virus?
- serologic tests (ELISA, hemagglutination inhibition)
- 4-fold or more increase in IgG antibody titters when acute serum and convalescent serum obtained 21 days apart indicates seroconversion
What are the clinical criteria for West Nile Fever?
Fever and one of: myalgia arthralgia headache fatigue photophobia lymphadenopathy maculopapular rash AND history of exposure
When do you need to notify public health about west nile virus?
- any confirmed cases
- if pt develops WNV within 2 weeks of blood or organ donation
- if pt develops WNV within 4 wks of receiving a transfusion or organ donation
How many applications of DEET can you put on per day in a:
1) child 12 yrs
1)
Which groups are at-risk for or predisposed to severe influenza illness?
- asthma or other chronic pulmonary diseases
- cardiovascular disease (excl isolated HTN but does include CHD)
- malignancy
- chronic renal insufficiency
- diabetes
- hemoglobinopathies (eg sickle cell)
- immunosuppression or immunedeficiency
- RA, SLE, psoriatic arthritis, antiphospholipid syndrome, etc
- neurologic disease that compromises handling of secretions
- kids 40 or 3x z score)
- aboriginal kids
When should antiviral drugs be started for influenza?
as soon as possible, ideally in
Which kids should go on antiviral therapy for the flu even if they present after 48 hrs?
1) if require hospitalization
2) illness is progressive, severe, complicated
3) pt belongs to a group that is at high risk for disease aside from their age
What do you use to treat the flu and for how long?
5 days of treatment (can be longer if clinically indicated)
1st line is PO oseltamivir
2nd line is Zanamivir (inhaled or IV) - prefer IV if intubated
**technically not approved for kids
When should you consider zanamivir instead of oseltamivir for patients with the flu?
- pts not responding to oseltamivir therapy
- pts with illness despite oseltamivir prophylaxis
What is the risk of transmission of Hep B from an occupational needle stick with HBsAg-positive person?
2-40% (depends on the viremia)
What is the post exposure prophylaxis we should give to kids who get a needle stick from a needle they finds in the community?
If kid Hep B antibody or HepBsAg positive - no action needed
if not fully vaccinated against Hep B - test for HepBsAB and HepBsAg, if results not available in 48 hrs; give HBIG (ideally in 48 hrs) and Hep B vaccine asap but ideally within 7 days (if sAB or sAg positive then some the vaccine series and arrange follow up)
kid has been fully vaccinated against Hep B - test for antiHep B sAB, if anti-HBsAB positive then no further action required. If anti-HBsAB negative test for HBsAg; if HBsAG negative then give HBIG and Hep B vaccine; if HBsAg positive then arrange for follow up
What is the risk of acquiring HCV in occupational needle stick with Hep C from a known Hep C + person?
3-10%
What is the post-exposure prophylaxis for Hep C if a kid finds a needle and sticks themselves with it?
-none at the moment
Under what circumstances is post-exposure prophylaxis indicated for HIV needlestick?
if it involves fresh blood
What are the recommendations for a needlestick that happens in the community?
- clean wound with soap and water ASAP, do not squeeze
- assess probability of exposure to mucous membranes, open cut
- determine immunization status for tetanus and Hep B - give tetanus or IgG as needed
- documentation is really important (type of needle, where it was found, if there was visible blood on it)
- get baseline Hep B, HIV and Hep C status
- don’t test needles/syringes
- test the user if available
For which kids after a needlestick would you give HIV prophylaxis? What would you give?
- if was high risk (source is likely HIV+, needle/syringe had visible blood, injected blood)
- If PEP - start within 1-4 hours, not recommended beyond 72 hrs of injury
- if undecided then prophylaxis immediately and can discontinue later
- For low-risk situations - zidovudine + lamivudine x4 weeks
- For high-risk situations - zidovudine + lamivudine + lopinavir/ritonavir x 4 weeks
What would be your follow up for a kid after a needle stick and who is on PEP?
- follow up at 2 days, 2, 4, 6 weeks for labs (CBC, AST, etc)
- 4 weeks - give 2nd Hep B vaccine (if appropriate)
- 6 weeks - test for HIV antibodies
- 3 months - test for HIV antibodies, anti-HCV antibody
- 6 months - anti-HIV, anti-HCV and antiHBsAg antibody, 3rd hep B vaccine
- if anti-HBsAB negative at 6 months, test again 1-2 months after the 3rd dose of the vaccine
- if still negative test for HBsAg
- if negative for both, give a 4th dose of Hep B vaccine and test again one to two months later
- if still negative refer to an appropriate specialist
How have the recommendations regarding management of HIV positive women in pregnancy affected vertical transmission of HIV?
-reduced it from 25-40% to
True or False. HIV testing is recommended for all pregnant women in Canada.
True
How should you manage a pregnant mum at high risk of HIV in terms of testing during her pregnancy?
-even if test negative early on, retest at the beginning of the 3rd trimester and at the time of delivery
If a women is HIV positive and is pregnant how should she be managed during her pregnancy?
- by an HIV expert
- should be treated with cART and monitored for viral suppression
Should pregnant women with HIV be delivered by c-section?
-elective c-section prior to labour for those not on cART and/or anticipated or documented to have inadequate viral suppression near delivery (viral load >1000 copies/mL)
How should an HIV positive pregnant mum be managed during labour?
-should get IV zidovudine regardless of antepartum ART regimen, mode of delivery or viral load near delivery
When should medication be given to babies born to HIV positive mums? When is it almost considered ‘too late’?
- as soon as possible
- ideally within 6-12 hours of birth
- efficacy is likely completely lost when initiated beyond 72hrs
What medication do you give to an infant born to an HIV positive mum and for how long?
- If mum received cART during pregnancy, had undetectable viral load before delivery then give zidovudine mono therapy for 6 weeks
- if mum did not consistently receive cART during pregnancy regardless of the reason, the most recent viral load was either detectable (greater than 40 copies/mL) or was not documented in the 4 weeks preceding delivery of the mum did not get IV prophylaxis then give the infant triple cART or zidovudine + nevirapine (nevirapine is only 3 doses, zidovudine is for 6 weeks)
When can lopinavir/ritonavir be used in babies and why?
-cannot be used until at least 42 weeks corrected and postnatal age of 14 days due to reported serious toxicities if given before that
Can you breastfeed if you are HIV positive?
no. Should be formula fed only.
True or false. Pre mastication of food by HIV-infected caregivers has been implicated as a potential route of HIV transmission to young infants?
True. (make sure to ask about this in your history)
What is the bloodwork for diagnosis that needs to be done for infants born to HIV positive mums?
- qualitative or quantitative HIV DNA or RNA PCR
- test with 2 separate tests, one taken after 1 month of age and the second at or beyond 2 months of age
- if the child received cART at least one of the PCR tests should deb done at or beyond 4 months of age
- need to also do a serological assay between 18-24 months
What are the side effects of zidovudine?
- anemia and neutropenia (both reversible)
- sometimes need to stop the drug because of it
- potential risk of mitochondrial dysfunction (suspect if end organ dysfunction)
What is the long term follow up for infants born to mums who are HIV positive and why?
-annual physical exams extending into adulthood because of the potential carcinogenicity of the nucleoside analogues and these kids were exposed in utero and in the neonatal period
What is an empyema?
-intrapleural pus
What are the 3 stages of an empyema?
- Stage 1 - moderate to large exudative parapnemonic effusion
- Stage 2 - fibropurulent, with locations
- Stage 3 - organized with thick fibrinous peel
What are the common pathogens for empyemas?
-Strep pneumo
-GAS
-Staph aureus
+/- MRSA
What are signs of progression to complicated pneumonia?
- fails to respond to anitbiotics (fever persists after 48-72 hrs)
- persistent or worsening respiratory distress
- findings of a pleural effusion: decreased breath sounds, decreased chest expansion, dullness to percussion
Why do we do a chest US for a pleural effusion?
US to confirm it, estimate its size and differentiate free flowing effusion from loculated
How long do we treat complicated pneumonia for and when do we step down to PO abx?
treat for 3-4 weeks if no additional complications and patient has resolution of symptoms.
Change to PO when drainage completed, patient has been improving and prior to discharge.
Use Amox-Clav
What is the long term prognosis for kids who have had a complicated pneumonia requiring drainage?
- complete recovery of lung function + normalization of CXR in most kids
- CXR may take 2-3 months to return to near normal – only repeat at 2-3 months
- Minority have mild restrictive/obstructive PFT ∆s, but normal exercise tolerance
