What are the 3 stages of lyme disease?
1. Early localized disease: erythema migrans (painless and non-pruritic), may have fever, malaise, headache, myalgia and arthralgia2. Early disseminated disease: recurrence of erythema migrans distributed throughout body (cutaneous dissemination of spirochetemia), lyme carditis, facial nerve palsy, aseptic meningitis3. Late disease: large joint arthritis (usually knees)
Why is 2 step testing required for lyme disease diagnosis?-causes for false positives?
ELISA first, then western blot-western blot is necessary to confirm diagnosis since ELISA can be falsely positive from other spirochetes, viral infections or autoimmune diseases
What is the Jarisch-Herxheimer reaction?
Fever, headache, myalgia and aggravated clinical picture lasting
A child who has completed the full course of Lyme disease antibiotic treatment returns within 3 months with chronic complaints of fatigue, joint and muscle aches. What is your diagnosis?
Post-treatment lyme disease syndrome-exact cause unknown-10-20% of cases-lingering symptoms may be result of residual damage to tissues and immune system-this is NOT evidence of persistent infection-no treatment available (more abx will not help)
What is the recommendation for post-exopsure prophylaxis for lyme disease?-when is it indicated?
There is no consensus on whether we should do it-some experts recommend for children > 8 yo after a tick bite in a known endemic area: doxycycline PO x 1 dose within 72 hrs of removing a tick-insufficient data to suggest amoxil prophylaxis for young children
A mother comes to you with mastitis and a breast abscess. She asks if she should continue breastfeeding. What do you recommend?
Continue breastfeeding UNLESS there is obvious pus! If there is, then pump milk and discard from the infected breast and continue to breastfeed from the other breast
A mother comes to you with a new diagnosis of TB. She asks if she should continue breastfeeding. What do you recommend?
Main route of transmission is airborne, NOT via breastmilk BUT tell mom to delay breastfeeding until she has received 2 wks of appropriate anti-TB therapy. -should also provide TB prophylaxis for infant-infant can be fed EBM during the 2 weeks of no breastfeeding
What are the only maternal infections that are a contraindication to breastfeeding? (5)
1. HIV2. Human T cell lymphotrophic virus (HTLV)3. TB (until mom has completed 2 wk course of anti TB meds)4. Untreated Brucellosis (infection may be passed through breast milk) 5. HSV lesions directly on the breast (until lesions are crusted over) - can still use EBM
Can mothers with Hep A, B or C breastfeed?
Yes! -For Hep A, give baby Hep A immunoglobulin for prophylaxis.-For Hep B, give baby infant HBV immunoglobulin at birth and immunization with HBV vaccine
What is a contraindication to primiquine treatment for malaria?
Which is the only antibiotic where you should discontinue breastfeeding x 12-24 hrs to allow excretion of dose after taking each dose?
What are nits?
Eggshells where baby lice (nymphs) are born from
What is an infestation with lice called?-how are head lice transmitted?-how do you make a definitive diagnosis of head lice?
Pediculosis-direct hair-to-hair contact-controversial whether fomites can transmit lice-definitive diagnosis requires detection of a living louse (presence of nits may indicate that a past infestation occured but may not be currently active if you cannot find a louse)
What are the different treatment options for head lice infestations?
***Need 2 treatments 1 wk apart-minimize body exposure, do not let the child sit in the bath water as the hair is being rinsed!1. Pyrethrins shampoo-caution in people who have ragweed allergy as may cause allergic reaction-safe2. Permethrin rinse-safe3. Lindane shampoo (2nd line)-neurotoxicity to both lice and humans-concerns with bone marrow suppression with skin absorption-do NOT use in young children, infants, pregnant/nursing mothers or people with history of seizures4. Noninsecticide = Resultz (myristate/cyclomethicone)-dissolves waxy exoskeleton of louse leading to dehydration and death-do not use for children
You have treated a child for head lice but they come back within a week with continued infestation. What is your differential diagnosis for treatment failure? (3)
1. Wrong diagnosis? Make sure you look again for a living LOUSE before you say this is treatment failure (not just presence of nits)2. Poor compliance with instructions for proper application of topical insecticide or lack of secondary application or reapplication too soon after 1st3. New infestation acquired after treatment
You have treated a child for head lice but they come back within a week with continued scalp itching. What do you tell them?
Itching post-topical insecticide is common and does NOT mean that a reinfestation has occurred! Topical insecticide can cause rash/itching. Topical steroids/antihistamines may help.
Is wet combing useful either alone or in combination with a topical insecticide for curing head lice infestations?
No! Shown in multiple trials to not be useful
You have diagnosed a child with head lice infestation. Mom asks if he should be kept home from school until he is lice-free. What do you say?-mom also asks you if she should disinfect all his personal items. What do you say?
No! He can still go to school as long as there is no head-to-head contact! -no clear data on whether disinfection of fomites leads to decreased chance of reinfestation. -Head lice cannot survive far away from scalp and nits are unlikely to hatch at room temperature.-so overall, just clean things with intimate contact with the head like hats, brushes/combs, pillowcases --> dry in hot dryer x 15 mins, place in occlusive plastic bag x 2 wks, or wash in hot water
What is the risk of vertical transmission with:-untreated primary or secondary syphilis-early latent syphilis-late latent syphilis
-Untreated primary or secondary syphilis: 70-100%-early latent syphilis: 40%-late latent syphilis: 10%
A baby is born but mom has never been tested for syphilis. Baby is completely well and mom wants to go home. What is your management?
If syphilis serology was not performed during pregnancy, do not discharge the newborn home until maternal serology has been drawn and follow-up of results has been arranged
What is the infectious etiology of syphilis?
What are causes of false-positive tests for syphilis? (2)
1. Autoimmune conditions2. Lyme disease
What is the screening approach used in Canada for syphilis?-which of the tests will remain positive for life despite treatment?-which of the tests is used to monitor effectiveness of treatment?
Use nontreponemal tests (RPR ie rapid plasma reagin) or VDRL ie. venereal disease research lab test) as initial screen, then confirm a reactive result with a treponemal test (fluorescent treponemal antibody absorption test = FTA-ABs)-treponemal tests remain positive for life (ie. FTA-ABs)-RPR titres is used to stage infection and to monitor the response to treatment (may revert to nonreactive after treatment)
A pregnant woman comes to you with a reactive treponemal test and a nonreactive RPR during pregnancy with no history of treatment and no evidence of early primary syphilis. What do you do?
This is a sign of late latent syphilis and thus there is risk of vertical transmission thus you TREAT for late latent syphilis: Benzathine Pen G x 3 doses on weekly basis
A pregnant woman comes to you with a reactive RGR and negative treponemal tests (FTA-ABS & TP-PA). What is your diagnosis?
False positive! It is not possible for your RPR to be positive while treponemal tests are negative in true syphilis!
What is the most common way that congenital syphilis is diagnosed?
Diagnosis relies on positive lab and/or radiographic findings since MOST infants with early congenital syphilis (syphilis diagnosed in 1st 2 years of life) are asymptomatic at birth
Aside from laboratory testing, how else can you diagnose congenital syphilis?
You can examine any skin lesions, nasal discharge, placental lesions or umbilical cord for treponemes with darkfield microscopy or FTA-ABS
What is necrotizing funisitis?
Umbilical cord that looks like a barbershop pole: pathognomonic finding for congenital syphilis
What are the clinical features of congenital syphilis? (9)
1. Spontaneous abortion/stillbirth/hydrops fetalis: 40% of cases if acquired during pregnancy2. Necrotizing funisitis3. Rhinitis/snufles4. Diffuse maculopapular rash including palms/soles5. HSM6. Lymphadenopathy7. Neurosyphilis8. Osteochondritis/perichondritis seen radiographically9. Anemia/thrombocytopenia
What are late clinical features of congenital syphilis? (4)
1. Interstitial keratitis2. Hutchinson teeth3. Mulberry molars4. 8th CN deafness