Week 8 Infectious Disease Flashcards
HIV screening guidelines
13 and 64 yrs get tested for HIV at least once
if higher risk, getting tested at least once a year.
IgM
early response; detected 5-10 days before sx onset
IgG
later response
long term
made after exposure (secondary response)
hepatitis A transmission and sx’s
fecal oral transmission
high risk: IV drugs, homeless, chronic liver dz
fever, jaundice, anorexia, nausea, malaise, myalgia
most children < 6 yrs are asymptomatic
hepatitis A management
- supportive care
- hydration
- antiemetics
- no etch
- vaxx HH / sex partners, high risk (MSM, liver problems, homeless, hepatitis b/c, high risk settings)
- recover in 2 months
- does NOT develop chronically! acute only
when would hep A need hospitalization?
- Intractable vomiting
- severe electrolyte or fluid imbalance
- altered mental status
- INR > 1.5
- evidence of fulminant disease
hepatitis B transmission
-
blood & bodily fluids (tattoo, needles, razors, saliva, semen)
- NO BREAST FEEDING
- can cause acute and CHRONIC hepatitis
- surface antigen HBsAg: -
- core antibody anti-HBc: +
- surface antibody anti-HBs: +
immune from natural infection
- surface antigen HBsAg: -
- core antibody anti-HBc: -
- surface antibody anti-HBs: +
immune due to hep b vaccination
- surface antigen HBsAg: +
- core antibody anti-HBc: +
- surface antibody anti-HBs: +
- IgM anti-HBs: -
acute infection
- surface antigen HBsAg: +
- core antibody anti-HBc: +
- surface antibody anti-HBs: -
- IgM anti-HBs: -
chronically infected
who is at risk for hepatitis B?
- Hemodialysis pts
- highest risk: Infants (born from infected moms)
- Sex parters , house hold contats
- occupational (health care workers)
- MSM
- Iv drug users
Hep B sx’s
- Fatigue, fever, n/v
- Arthraliga
- Similar to hep A
- > 60 yrs = severe fxn
- < 5 yrs = asx
- > 5 yrs = sx’s
first lab indicator of hepatitis B infection?
elevation of hepatitis B surface antigen and elevated ALT
if have hepatitis B, what else should you screen for?
hepatitis C and D, HIV
when to treat hepatitis B?
- only in active phase: ALT doubled,
- chronic hep B when hep B ‘e’ antigen is + and DNA viral level > 20k
- entecavir or tenofovir safe and effective x 12 months after HBsAg is - and HBV DNA is undetectable
if mother has chronic hepatitis B (hep B surface antigen +) after an infant is born…
infant should get hep B vaccine and immunoglobulin within 12 hours of birth
if not, 90% of infants will get chronic hep B
test infant in 6-9 months for antigen and antibody
hepatitis C transmission
blood =
IV drug use, vertical transmission, razors, toothbrushes, IV, piercings
hepatitis c diagnostic
+ HCV antibody and + HCV RNA
What if hepatitis C antibody is negative and RNA positive?
- Acute infxn
- If asymptomatic, screening for hep C
- Hard to tell acute or chronic but if they have sx’s the most likely acute
Hepatitis C antibody and RNA are positive?
- When was last test? If - in past 12 months, this is a new acute infxn if now +
Hepatitis C antibody positive and RNA is negative and asymptomatic ?
had hep C and recovered (don’t go onto chronic)
OR
false + so repeat in a few weeks
who should get tested for hepatitis c?
every adult at least once 18+ , every pregnant women, those with risk factors regularly
one time test regardless of age or high risk: HIV, hemodialysis, organ transplant before 1992
if pt tests positive for Hep C 2 yrs ago, has + antibody test, RNA +, next step is?
order RUQ ultrasound to assess for evidence of cirrhosis and carcinoma
if mom is pregnant with hep c, when do you check child for hep c?
at 18 months
can you breastfeed with hep c?
yes
when is AIDS dx?
CD4 < 200
what is the 4th generation HIV test?
combines antigen (in blood as early as 15 days after exposure) and antibody test (takes 30 days to be detected)
screens HIV 1 & 2
- if antigen reactive: do viral load/NAAT = if + = reactive
- if - initial test was false +
acute HIV sx’s
- Mono like illness
- Fatigue
- Fever
- Sore throat
- Cervical lymphadenopathy
- Night sweats
- Diarrhea
- Skin rash
- Trunk NOT itchy
- Headache
- Arthralgia
- Myalgia
- Oral or genital ulcers
- leukopenia, or anemia, or thrombocytopenia, and also elevation in the liver transaminase.
early treatment of HIV to
decrease transmission, decrease viral load
continue indefinitely of 3 ART (2 nucleosides and integrate strand transfer inhibitor)
important considerations when someone is diagnosed with HIV
- Have partner start Prep
- Up to date with hep, flu, pneumoc, covid vaccines
- Monitoring labs and side effects of ART
- Assessing adherence
- Discuss meaning of viral load and HIV spread
- Screen for STI, TB, osteopenia (from long term use of ART)
- Screen for cervical cancers bc HPV risk malignancies
- No evidence of opportunistic infections (PE)
- Other high risk behaviors like IVDU
HIV + mom concerned about unborn child. with effective therapy, risk of transmission
lowered to < 2 %
after delivered, baby started on AZT for 4-6 wks to prevent HIV infxn
steps to prevent HIV transmission from mom to baby
- mom with HIV take HIV medicines during pregnancy and childbirth.
- Their babies are given HIV medicine for 4-6 weeks after birth.
- Goal: lower viral load < 1000 in mom = dec transmission to baby
- Women with a high or unknown level of HIV in their blood may have a C-section
- No breastfeeding
- Newborn need RNA/DNA check at 2 wks, repeat 1-2 months, then 4-6 months, then 12-18 months.
- Negative HIV antibody confirms bb not infected
- If mom has < 1000 viral load, can do vag delivery
- If mom has high viral load, C section considered
is infant’s blood is taken day 1 and at 2 week mark and is + for HIV, this means
we don’t know!
we expect to see antibodies up to 6 months bc it crosses the placenta so we have to test for HIV antibodies up to 6 months.
test viral load at birth, at 1-2 weeks, then 1-2 months, then 6 months
if 2 RNA are + = confirms dx
How should the HIV status of the infant be determined?
Viral load by PCR at 2-3 weeks, 1 to 2 months, and 4 to 6 months
HIV and pneumococcal vaccine?
ok to admin 1st dose of pneumococcal vaccine series now (if CD4 >100) but make sure its inactivated
HIV sx’s in children
Recurrent or severe infections
AOM, sinusitis, pneumonia, bacteremia
Growth failure • Pubertal delay •
Anemia, thrombocytopenia, neutropenia
• Hepatomegaly, splenomegaly • Opportunistic infections • Candidiasis • Diarrhea
HIV med monitoring
osteopenia
infections
cancer
depo and progestin pills interactive
higher cardiovascular risk
highest risk of TB reactivation is
first 2 yrs
ghon focus
white spots when infected tissue dies in lungs from tb
risk factors that increase risk of latent to active TB
< 5 yrs old
diabetes
immunosuppression
highest rates: > 65 yrs, lowest: 5-14 yrs old
latent TB
- infected but doesn’t develop sx’s and don’t feel sick bc healthy immune system
- (if compromised immune syste, wil be active TB)
- Not contagious
- If not tx, can lead to active TB
active tb sx’s
- pulmonary disease, cough, fever, night sweats, hemoptysis, weight loss, and loss of appetite.
- Symptoms in children are typically more severe.
- So extrapulmonary TB is more common in children.
TB can affect what areas
lungs, lymphatic system, the pleura, the bone and joint, and peritoneal, GU, and meningeal.
TB gold standard analysis
sputum culture but takes few weeks to come back
preferred method for TB testing children < 5?
what is preferred if they got a BCG vaccine?
TB Skin test
interferon gamma release assay
TB management
Referral to TB specialist, DPH
- Empiric treatment
- 4 drug for 6 months:
- Isoniazid
- Rifampin
- Pyrazinamide
- Ethambutol
- Observation or call to make sur compliance
- Many SE’s
- Med compliance
- Monitor SE
- CBC, renal, liver
- Paraesthesia common SE
- Screen for HIV
how does the TB skin test work
return in 48-72 hrs, measure induration
interpreting skin test positive >15mm, >10mm, >5mm?
>15mm: general pop
>10mm: high risk, < 4 yrs old, job, IVDA, chronic dz, recent immigrant
>5mm: immunosuppressed/HIV, recent TB contact, children suspected to have TB, organ transplant recipients
if +, want to r/o active TB but asking for sx’s and chest x ray. if all negative = latent TB
can have a false + if BCG vaccine recent or had TB in past
when would you do a IGRA (quantiferon gold) over a Mantoux test?
- 5 yrs+
- unlikely to f/u
- poor transportation
- PPD in past
- treated for latent TB
TB management
if have HIV = refer
r/o active TB by asking sx’s and chest xray
defer tx in preg til after delivery
tx 4-6 months- 9 months
educate SE’s
admin vitamin B12
how is Lyme disease ticks transmitted
via deer ticks
must be attached for at least 36 hrs to be transmitted; will fall off after 5 days
lyme prevention
DEEP
doxy prophylaxis if > 8yrs old and IF have tick bite, live in endemic area , tick ON for 36 hours, pt removed tick w/in 72 hrs or tick engorged with blood
lyme tick testing/serology
NOT recommended esp with a pt with primary erythema migrans
dx based on presentation and give doxy!
best thing is educate and prevent
lyme dz diagnosis factors
- clinical characteristics: erythema migrans > 5cm with central clearing
- epidemiologic link (possible tick exposure in an endemic area
- start doxycycline for 10 days
- no test of cure
lyme stage 1 early localized
erythema migrans - bulls eye rash
no pain or itchy, fever, fatigue, myalgia
lyme stage 2 early disseminated
- Cardiac sxs: carditis and AV block
- Ceftriaxone IV then switch to oral doxycycline
- Flu like sx, lymphadenopathy, neuro: facial nerve palsies, arthralgies (common)
lyme stage 3 late disseminated
and post Lyme disease syndrome / chronic lyme
- 60% arthritis
- Peripheral neuropathy
- encephalopathy/myelitis
- Dx is controversial
- Fatigue, joint pain after tx for lyme
- No benefit for long term antib use and can cause harm. Evaluate if it’s something else that’s not lyme dz
anaplasmosis sx’s and tx
NO rash
GI symptoms (n/v/d)**
fever, chills, thrombocytopenia
if suspected, give doxycycline x 10 days (can use in preggos)
ehrlichiosis sx’s and tx
rash, fever, chills, leukopenia
start doxy asap!
babesiosis sx’s
- invades erythrocytes = hemolytic anemia/tissue hypoxia
- Blood transfusions or deer tick
- May be asymptomatic
- Flu-like symptoms
- Fatigue
- Nausea and vomiting
- Thrombocytopenia
- Hemolytic anemia
- Elevated liver enzymes
- Proteinuria or hematuria
Babesiosis diagnostics and management
- have viral like illness, was outdoors in babesial endemic area, dx with lyme dz
- PCR
- Blood smears
- CBC/diff
- LFT’s
- Management
- Asymptomatic = no tx
- When treated, expect improvement in 3 days
- Mild to moderate
- Oral atovaquone plus azithromycin
- Severe
- Hospitalization with IV antibiotics (older, comorbidities, immunoc)
- RBC exchange transfusion
- High grade parasitemia
