Peds infectious disease Flashcards
What are the types of vaccines
- Live: virus is alive but weakened (MMR, varicella, Flumist)
- Inactivated: killed virus, capsid proteins remain and are antigenic
- Viral particles: no viral DNA
- Subunit vaccine: virsl proteins only
- Toxoid: inactivated toxin stimulates Ab production (tetanus)
Contraindications to vaccinations include
Immunocompromised or pregnant (no live)
Anaphylaxis Hx to a certain vaccine
Egg or chicken allergy (flu and yellow fever)
Moderate-severe illness
You should NOT give the live flu vaccine to an immunocompromised individual if
<6 months old
Hx of stem cell transplant in last 2 months
Has graft vs host dz
has SCID (severe combined immunodeficiency)
IF you give a live vaccine to a patient that is immunocompromised, they must
avoid contact with household members for 7 days
Examples of acquired immunodeficiency are
HIV cancer transplant sickle cell disease acquired asplenia meds that suppress immunity diabetes pregnancy
These are NOT contraindications to vaccines
mild illness low grade fever recent exposure to ID mild-mod rxn to previous vaccine on Abx breast feeding household contact is immunosuppressed premature malnourished FHx of SIDS or Sz
What vaccines are administered inkids
Hep B, 3: birth- 2 mo- 6-9 mo Rotavirus, 3: 2 mo- 4 mo- 6 mo DTaP, 5: 2 mo- 4 mo- 6 mo- 15-18 mo- 4-6 y/o Hib, 4: 2 mo- 4 mo- 6 mo- 12-15 mo PCV13, 4: 2 mo- 4 mo- 6 mo- 15-18 mo PPSV23: 1 shot if high risk, >2 y/o IPV, 4: 2 mo- 4 mo- 6-18 mo- 4-6 y/o MMR 2: 12-15 mo, 4-6 y/o Varicella, 2: 12-15 mo, 4-6 y/o Hep A, 2: 12 mo- 18 mo HPV, 3: 0, 1 month, and 6 months MCV4, 2: 11-12 y/o, booster 16 y/o
Contraindications to rotavirus vaccine include
weak immune system
recent blood transfusion
major GI illness
Hx of intussesception
Contraindications to IPV vaccine
allergy to neomycin, streptomycin, or polymyxin B
What is Synagis (palivizumab)
RSV immunoprophylaxis, not a vaccine
Given to high risk kids <2 y/o (premies <29 wks)
Monthly injections during RSV season
Very expensive
What is in the flu vaccine
INactivated strains that change every year based on most likely strains
Usually has 3 most likely, but can get quadrivalent
Includes H1N1
-For everyone 6+ months
-If 6 mo-8 y/o, need two doses 4 weeks apart on your first time getting the vaccine
What is in the inhaled flu vaccine
Quadrivalent strains of live but WEAKENED virus (can’t cause flu)
-For everyone 2-49 y/o
Contraindications to the live flu vaccine ae
severe allergi to LAIV 2-7 y/o on ASA pregnant women immunosuppressed 2-4 y/o w/ asthma
Normal reactions to vaccines are
Fussiness (<3 hours, consolable)
Tiredness
Low grade fever (<101.5)
Pain, red, swollen at injection site
Abnormal reactions to vaccines are
inconsolable crying for 3+ hours High fever (>104) Seizure Neuro abn Anaphylactc reaction (facial/oral swelling, dyspnea)
What must you report to the AZDHS
vaccine preventable diseases! they have a centralized immunization registry
When considering peds ID, you must rule out
allergic rhinitis asthma CF FB aspiration conditions interfering with skin barrier function
Warning signs for immunodeficiency include
Basically, too many illnesses too soon 4+ ear infx in 1 yr 2+ sinus infx in 1 yr 2+ mo on Abx w/ no effect 2+ PNA in 1 yr FTT recurrent deep abscesses persistent thrush need IV abx to clear infx 2+ deep seated infx w/ septicemia FHx of primary immunodeficiency
When testing for immunoglobulins in babies, what do they mean
IgM and IgA levels are from babies; pay attention to these!
IgG is inherited from mom
What is the complement system
System of plasma proteins that interact with pathogens to mark them for destruction by phagocytes
What are phagocytes
WBC that contribute to immune defenses by ingesting microbes and other cells infected with foreign particles
What are T cells
Start as haematopoietic stem cells that go to the thymus
CD4 are helpers, they release cytokines to signa immune response
CD8 are cytotoxic, they perforate bad cell walls and release cytotoxins to kill them
Suppressors (CD4 and 25) play a role in preventing organ specific autoimmunity AKA keep the system in check from killing everything
What are B cells
Make antibodies when a foreign antigen triggers the immune response
bind intact antigens
remember antigens
create B cell receptors
undergo mitosis and make many clones
Stay in secondary lymphoid organs (spleen and lymph nodes)
The next time that antigen enters the system, B cells activate!
What is primary immunodeficiency
Inherited defects in any part of the immune system
What is humoral immunodeficiency
Impaired Ig production
How do peds present with primary immunodeficiency
recurrent, severe URI/LRTI (OM, sinusitis, PNA)
infectios with encapsulated bacteria (Hib, Strep pneumo, N meningitidis, GB strep, Klebsiella, Salmonella typhi)
Meningitis 1+ times
Recurrent candidiasis
Poor growth, FTT
Unexplained splenomegaly
Delayed umbilical cord detachment
To diagnose primary immunodeficiency, you must rule out
underlying chronic disease
autoimmune, inflammatory, malignancy, allergic
If suspecting primary immnodeficiency, get these diagnostics
CXR: look at thymus
CT of involved system
What is the MC immunodeficiency
Selective IgA deficiency (normal IgG and IgM) in child >4 y/o
Most are ASx
If Sx are present, what are they for IgA deficiency
recurrent sinopulmonary infections AI d/o GI infection Allergic disorders Anaphylactic transfusion rxn to anti-IgA abs
What is common variable immunodeficiency
Poor vaccine response + Decrease in blood levels of IgF + severe decrease in IgM and/or IgA
B cells must be present
Other immunodeficiencies must be ruled out
When do patients usually present with CVID
Puberty!
Variable manifestations b/c it is not a single disease
Recurrent sinopulmonary and GI infections
At risk for AI diseases and malignancies
What is severe combined immunodeficiency
Group of rare immunologic disorders with severe T cell deficiency (very susceptible to infection)
MC form is X linked (male)
Part of newborn screening
“Bubble boy” disease
If not treated, patient will die by 1 y/o
How does SCID present
1+ severe infections in first few months after birth (PNA, meningitis, bacteremia) or opportunistic infx (P. jiroveci, candidiasis, CMV)
Illness s/p live vaccine
No visible thymus on CXR
No tonsils or lymph nodes on PE
How do you treat SCID
Stem cell transplant
Gene therapy
Ig replacement therapy
What is DiGeorge syndrome
Deletion of chromosome 22q11.2
Causes cardiac defects (tet, ASD, VSD, truncus arteriosus, interrupted aortic arch)
Immune dysfunction (hypoplastic thymus) w/ T cell deficit
Cleft palate
Hypocalcemia
What is ataxia telangiectasia
rare, auto-recessive, neurodegenerative d/o caused my AT mutation on gene at 11q22-23
Presents w/ progressive cerebellar ataxia and oculocutaneous telangiectasias
How do children with ataxia-telangiectasia present
Don’t fully develop gait
nystagmus
Telangiectasia of face, neck, conjunctiva
Malignancy common >10 (lymphoma)
What is bacterial meningitis
a medical emergency!
Mortality rate if untreated is near 100%
Neurologic sequelae are common among survivors
-Present with Opisthotontos posturing*
How do you treat bacterial meningitis
Abx covering strep pneumo, N. meningitidis, and Hib within ONE HOUR
-0-29 days: Ampicillin, Cefotaximine, Vancomycin, and Acyclovir +/- Gentamicin
-30-60 days: Ceftriaxone, +/- vancomycin
(Abx have to reach peak in CSF to treat!)
List abx that cover specific organisms
S. pneumo, N. meningitidis, and Hib: Ceftriaxone or Cefotaxime Listeria: Ampicillin GBS: Ampicillin S. aureus: Vancomycin Gram (-) rod: Ceftriaxone, Cefotaxime Herpes: Acyclovir
ASAP after LP you should administer
Empiric Abx and dexamethasone
Treat hypoglycemia, acidosis, and coagulopathy as necessary
How does Bacterial arthritis usually present
In hip and knee (>1 joint esp in neonates)
Septicemia (irritable, poor feeding)
Cellulitis
Fever w/o focus of infection
Lack of use of affected joint
-older kids also have fever and constitutional Sx
What bacteria is the common cause of bacterial arthritis
<3 mo: GBS (agalactiae)
3 mo- 3 yr: group A strep (pyogenes), or kingella kingae
>3 yr: GAS
Suspect bacterial arthritis if __ and order
Monoarticular pain, fever, and redness
Get a CBC, ESR, and blood culture; imaging, consult
What antibiotics do you give for bacterial arthritis
Antistaph: Naficillin, Oxacillin, Vancomycin
+ Cefotaxime (also covers gonorrhea)
consider antifungals
What do you order and how do you treat osteomyelitis
CBC, ESR, CRP, blooc culture
Consult
IV abx
