Bronchiolitis - LSU School of Medicine

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Transcript Bronchiolitis - LSU School of Medicine

ID Part Deux
Test Question

I will watch the summer olympics this
year.
 A. True
 B. False
Intro
Bronchiolitis is caused by inflammation of the
bronchioles by an acute viral infection
 *Most common lower respiratory tract
infection in infants and children under 2
 Infectious agents:

 RSV (most common)
 Adenovirus
 Metapneumovirus
 Influenza virus
 Parainfluenza virus
*Epidemiology of RSV

*Know the mode of transmission
 Direct or close contact with contaminated
secretions
○ Large droplets at short distances
○ Fomites
 RSV can persist on environmental surfaces
for several hours
○ ½ hour on hands
*Epidemiology of RSV

*Incubation period
 Ranges from 2 to 8 days

*Period of communicability
 Usually 3 to 8 days
○ Shedding can last longer in young infants and
immunosuppressed people (3 to 4 weeks)

*Age of onset
 Most infants infected during 1st year of life
 Virtually all by 2 years of age

*Peak season
 Winter and early spring
Question #1

All of the following patients are at high
risk for morbidity and mortality from RSV
infection EXCEPT:
 A. A premature infant
 B. A 1-month-old with unrepaired congenital
heart disease
 C. A 4-month-old ex-32 WGA with BPD
 D. A full-term infant with hyperbilirubinemia
 E. A 2-month-old with cerebral palsy
*Epidemiology of RSV

*Risk factors for morbidity and mortality
 Prematurity
 Unrepaired congenital heart disease
○ Pulmonary overcirculation
 Chronic lung disease
 Airway abnormalities
○ Laryngomalacia
○ Tracheomalacia
○ Cleft lip/palate
 Neurologic abnormalities
*Clinical Manifestations
History of recent upper respiratory tract
symptoms followed by cough, tachypnea, and
increased work of breathing
 Physical findings:






Nasal congestion
Rhinorrhea
Cough
Tachypnea
Increased respiratory effort
○ Nasal flaring, grunting, retractions
 Crackles, wheezes, upper airway noise
 Apnea
○ May be only presenting sign in young infants
Course
Characteristic pattern
 Expect worsening symptoms

 Peak symptomatology on day 3 to 4
 “Day of illness” important for anticipatory
guidance, admission/discharge decisions,
etc.
Diagnosis


Based on history and
physical
Routine lab and
radiologic studies are not
recommended
 CXR not routinely
recommended
○ Often are abnormal
appearing (hyperinflation,
atelectasis, infiltrates)
○ Do not correlate with
disease severity
○ Do not guide
management
○ May prompt unnecessary
antibiotics for PNA which
is rare in viral bronchiolitis
Diagnosis
Viral studies are not recommended for
diagnosis
 *Know the laboratory diagnosis of RSV

 Viral antigen detection
○ Enzyme immunoassay technique
○ Sensitivity mostly 80 to 90%
○ From nasopharyngeal specimens
 Viral culture
○ Requires 1 to 5 days
○ From nasopharyngeal secretions
○ Sensitivity varies among laboratories
Question #2


A 3-month-old male ex-38 WGA comes to the
emergency room with a history of upper respiratory
symptoms for 3 days, fever, decreased appetite and
increased work of breathing. On PE his vitals are T
99 RR 45 HR 185 BP 90/65 and Sat 96% on room
air, he has nasal congestion, mild retractions, and
course breath sounds He has an older sister in preK.
Of the following the MOST appropriate next step in
management is:





A. Start albuterol nebs
B. Give Orapred 2mg/kg
C. IVFs with normal saline
D. Supplemental oxygen
E. Nasal decongestants
Management

*Plan the management of RSV infection
 Supportive care
 Hydration
 Oxygenation
 Other measures (bronchodilators,
corticosteroids, antiviral agents, CPT, nasal
suction, decongestant drops) have been
shown to have impact on duration of illness,
severity of clinical course, or subsequent
outcomes
Management

Hydration
 ↑ RR, secretions, fever, poor feeding →
dehydration
 May require IV fluids or NG feeds
 Bronchiolitis causes ADH release → risk for
hyponatremia
○ Use isotonic fluids
Management

Oxygenation
 Results from impaired diffusion, V/Q mismatch,
plugging of bronchioles
 Goal is to maintain normal sats
 No clear consensus on pulse ox range
○ Aim for sats between 90 to 92%
 Monitoring
○ Schedule spot checks
○ Continuous pulse ox only for those with previous O2
requirement, risk for apnea, or with underlying
cardiopulmonary conditions
Managment

Bronchodilators
 AAP does not recommend routine use
 A monitored trial may be considered, but
only continued if clinical response is
documented
○ Diminished work of breathing
○ Decrease in RR
○ Improvement in hypoxemia
Managment

Steroids
 Based on current evidence, corticosteroids
should not be used to treat bronchiolitis

Ribavirin
 Should not be used routinely
 May be considered in special situations:
○ Organ transplant, malignancy, congenital
immunodeficiencies
 Very expensive
Management

CPT
 Bronchiolitis (V/Q mismatch) is unaffected by
regional CPT

Nasal suction
 May increase comfort and improve feeding
 Most beneficial before feedings and in response
to copious secretions

Nasal decongestants
 No proven efficacy, potential harmful side effects
 Should not be used in children under 2
Question #3

The major benefit of palivizumab
prophylaxis is:
 A. Decreased hospitalization rate
 B. Improved treatment
 C. Increased cost-effectiveness
 D. Lower mortality rate
 E. Shorter duration of illness
*Prevention

*Identify patients who may benefit from
prophylaxis
 Palivizumab (Synagis)
○ Monoclonal antibody (IgG) against RSV
 Candidates
○ History of prematurity
○ Infants with chronic lung disease
○ Infants with hemodynamically significant
congenital heart disease
Prevention
•Effectiveness of palivizumab beyond the second year is unknown
•Prophylaxis should be administered in 5 monthly doses
beginning in November
•Not overall cost-effective
Question #4
It’s December and a mom is in your office
with her 6 week-old daughter is worried
about RSV. Her older son who is now 4years-old had it as a baby and had to be
hospitalized. She asks you if there is
anything she can do at home to help
prevent her daughter from catching it.
 All of the following are ways to reduce the
risk of RSV EXCEPT:

 A. Avoid tobacco smoke
 B. Encourage breastfeeding
 C. Washing hands with soap and water
thoroughly
 D. Vitamin C supplements
 E. Alcohol-based hand sanitizer after contact
Prevention
Strict hand hygiene and isolation
policies
 Avoidance of tobacco smoke

 Independent risk factor for contracting
bronchiolitis

Encouragement of breastfeeding
 Contains immune factors that can prevent
RSV
 Neutralizing activity against RSV
Prognosis
Most recover without sequelae
 A portion develop recurrent wheezing

 40% have subsequent wheezing episodes
through 5 years of age
 10% have subsequent wheezing episodes
after 5 years
Question #5


An 11-month-old boy presents to your office with a
5-day history of fever, nasal congestion,
conjunctivitis, and the development of a rash over
the past 24 hours. The rash began on his head and
neck and spread to his trunk and extremities. The
family recently returned from a trip to Ireland. His
past medical history is unremarkable, and his
immunizations are up to date.
Of the following, the BEST test for diagnosing this
child’s condition is:





A. Measles IgM serology
B. Nasal aspirate for viral culture
C. Rubella IgM serology
D. Skin biopsy
E. Throat culture for Group A Streptococcus
Transmission

*Transmission:
 Direct droplet contact
 Airborne spread
Incubation period: 8-12 days
 Period of communicability: 1-2 days
before any symptoms appear until 4
days after the rash appears

*Clinical Presentation
8-12d

24h
Exposure Fever, malaise Coryza, cough,
48h
2-3d
conjunctivits Koplik spots Exanthum
 Exanthem: red/ purple papules appear at
hairline, then spread downward (@ toes by
day 3)
 Coalescence common on face and upper body
 Fades in same fashion (headtoe)
Measles
Koplik spots
*Control Measures


Isolation (airborne precautions)
Immunization/ Immune globulin
 First determine who is susceptible
○ <2 doses of MMR vaccine after the first birthday
○ Low titers in response to vaccine administration
○ No documentation of measles by a physician
○ Immunocompromised patients
 If susceptible:
○ MMR vaccine within 72hours of exposure
○ IM Immune globulin within 6 days of exposure:
 Household contacts if vaccine not given within 72h
 Immunocompromised patients
 Infants <12mo***
*Complications
OM
 Bronchopneumonia
 Laryngotracheobronchitis
 Diarrhea
 Acute encephalitis
 Subacute sclerosing panencephalitis
(SSPE)

Transmission

*Transmission:
 Person-to-person spread via droplet
inhalation
*Incubation period: 2 to 3 weeks
 *Period of communicability: several days
before to 2 weeks after the onset of the
rash
 In 2005, the CDC announced that
rubella had been eliminated from the US

 But, it’s still on the Boards!!
*Postnatal Clinical Presentation
14-21 d
Exposure Tender adenopathy (postauricular, posterior cervical, and occipital);
malaise, HA, low-grade fever, sore throat
1-5 d
 Exanthem (+/- Forchheimer spots)
 Exanthem: rose-pink maculopapules on face
that spread quickly to involve trunk and then
extremities

 Day 2: rash on face disappears, truncal rash
coalesces
 Day 3: rash disappears
Rubella
Forchheimer Spots
Question #6

All of the following are sequelae of
congenital rubella syndrome, EXCEPT:
 A. Sensorineural hearing loss
 B. Cataracts
 C. Radiolucenicies in the metaphyses of
long bones
 D. Heart disease
 E. Craniofacial abnormalities
*Congenital
Rubella
rate of infection 1st
and 3rd trimesters, morbidity
associated with 1st trimester
infection
Presentation:
Highest
 Blueberry muffin lesions
 Radiolucencies in





metaphyseal long bones
PDA (or ASD/VSD)
Sensorineural deafness
Cataracts/ glaucoma
HSM
IUGR
Question #7

A mother of one of your patients is in her first
trimester of pregnancy and just found out that her
internationally adopted niece has contracted rubella.
She wonders when it will be safe for her to be
around her niece again. You tell her:
 A. She should stay out of contact until the LAD resolves
 B. She should stay out of contact until the fever resolves
 C. She should stay out of contact until the exanthem
resolves
 D. She should stay out of contact until the exanthem
appears
 E. She does not need to worry…contracting rubella in this
stage of her pregnancy is unlikely to cause any sequelae
*Control Measures

Primary focus: preventing CRS
 Maintaining elevated vaccine coverage rates
in children and adolescents
 Providing adequate surveillance systems
 Timely investigations during outbreaks
○ Active cases should be reported to local public
health authorities
 Susceptible individuals should be kept out of
contact with anyone infected with rubella
○ Despite widespread vaccination, some women
of childbearing age may be susceptible
Neisseria meningitidis
*Know the epidemiology of
Neisseria meningitidis

 Five serotypes: A, B, C, Y, and W-135
○ B, C, and Y cause most cases in North America
○ More than 50% of cases in infants caused by
serogroup B → *NOT preventable with vaccines
 *Leading cause of bacterial meningitis in young
children
 Most often occurs in kids 2 and younger
○ Peak in kids under 1
○ Another peak in adolescents age 15 to 18
*Epidemiology

Asymptomatic colonization of the upper
respiratory tract is how the organism is
spread
 10 to 40% of adolescents and adults are carriers

Transmission occurs from person to person
through droplets from respiratory tract
 Requires close contact
 Outbreaks get media coverage
○ Less than 5% of cases associated with
outbreaks

Incubation period is 1 to 10 days
Question #8
You are discussing with medical students the
risk factors that increase the likelihood that
transmission from carriers will result in
meningococcal disease.
 Of the following groups, the risk of disease is
HIGHEST among:






A. School children
B. Vaccinated students living in college dorms
C. Healthy nonsmoking adults
D. Household contacts of an index case
E. Toddler in child care centers
*Risk factors

Environmental factors
 Crowded living conditions
○ College dorms, military barracks
 Secondary infection among household contacts is up
to 800 times that in the general population
 Active and passive tobacco smoke

*Understand which patients are at increased
risk of invasive and recurrent meningococcal
disease
 Terminal complement deficiency
 Hypogammaglobulinemia
 Anatomic or functional asplenia
Clinical Syndromes

*Know the major clinical syndromes of
Neisseria meningitidis
 Severe meningococcal septicemia
 Meningococcal meningitis

Systemic manifestations of the organism
reproducing in the blood
 50% have isolated meningitis
 10 to 15% have severe meningococcal
septicemia
 40% have a mixed picture
*Severe Meningococcal
Septicemia
Characterized by sudden onset, rapid
progression, and absence of localizing
findings
 More severe than meningitis
 Fatality rate is high (40 to 50%)
 Most patients have no
immunocompromise

*Severe Meningococcal
Septicemia

Symptoms and physical findings
 High fever, shaking chills, myalgias, extremity or back
pain
 Deteriorate within 6 hours
 Rash
○ Classically petechial
○ Often become hemorrhagic
○ Coalesce to form widespread purpura
 Purpura fulminans
○ Aggressive spread of purpura to large areas with
iscemic necrosis
○ Likely to have sudden drops in blood pressure and acute
adrenal hemorrhage (Waterhouse-Friderichsen)
Rash
*Severe Meningococcal
Septicemia
Early diagnosis and treatment still evades
clinicians
 Look for early clues

 Tachycardia
 Rash
○ Typically present in 24 hours
○ Fever and petechial rash is SMS until proven otherwise
 True rigors
 Severe pain in neck, back, and extremities
 Vomiting
 Concern of parent
 Exposure
Meningococcal Meningitis

*Signs and symptoms of typical bacterial
meningitis
 1 to 3 day non-specific prodrome with low-grade






fever and URI symptoms
Cushing triad can occur (bradycardia, HTN, resp.
depression) as ICP rises
Meningismus
Mental status changes
Sudden and severe headache with photophobia
GI complaints
Myalgias
Question #9


You are working in the ER and see a 14-month-old
boy, previously healthy and fully immunized, who
has had cold symptoms for the past 2 days. Late
this morning, he developed a temp of 101, malaise,
and discomfort. On PE you see scattered petechiae
over his trunk. He is alert, but very fussy.
Of the following, which is the GOLD standard to
make the bacteriologic diagnosis in this case?





A. PCR
B. Culture of normally sterile site
C. Gram stain
D. Antigen detection
E. Antibody titers
Diagnostic studies

*Know the diagnostic tests for invasive
meningococcal disease
 Gram stain
○ Of CSF is highly sensitive and specific
 Culture of sterile site
○ Gold standard
○ Can culture aspirate of purpuric lesion
 Antigen detection
○ In CSF can support diagnosis, but high false-negative
rates
 PCR
○ Useful in patients who have already received abx
○ Use in UK, but not widely in US
Diagnostic Studies
Lab tests may return too late or may fall
within normal range in a precipitous
course
 CSF

 WBC elevated, low glucose, elevated
protein
 However, a negative LP result is an ominous
finding in a patient with invasive
meningococcal disease
Question #10


You admitted a patient to the hospital with rapid
onset of fever, petechial rash, myalgias, and mental
status changes. You are worried about invasive
meningococcal infection. You intubate the patient,
begin IVFs, draw blood cultures and start
ceftriaxone. The patient is placed on droplet
precautions. The blood culture grows N.
meningitidis the next day. The nurse asks how long
the patient needs to be in respiratory isolation.
Of the following, the BEST answer is until the child:





A. completes 1 day of antimicrobial therapy
B. deferveces
C. is clinically stable
D. is extubated
E. is proven not to have meningitis
*Management

*Plan the treatment of a Neisseria
meningitidus infection
 First step is recognition and aggressive
treatment
 Refer to emergency care facility

IVFs
 Large isotonic fluid boluses
 Giving 60 to 100 ml/kg in first hour assoc.
with improved survival
*Management

Vasoactive agents
 Consider inotropic/vasoactive agents such as
dopamine or dobutamine
 Works best when intravascular fluid volume is
maximized

Airway
 Large volume IVFs may lead to pulm edema

Corticosteroids
 Physiologic doses of hydrocortisone may be
beneficial in those with SMS and poor response
to vasopressors
 Dexamethasone in MM
*Management

Antibiotics
•Patients treated with penicillin require oral rifampin to eradicate nasal
pharyngeal carriage state
•Require isolation and droplet precautions for 24 hours after start of
antibiotics
Vaccine
*Recognize that vaccines are
not available against N. meningitidis
serogroup B

 Meningococcal conjugate vaccine (MCV4)
○ Protects against A, C, Y, W-135 capsular groups
○ Recommended at 11 to 12 years of age
 Booster at 16
○ Unvaccinated adolescents through age 18 should
receive a dose at earliest opportunity
○ Age 2 to 55 for those at high risk
 Vaccine for infants under investigation
Question #11

A 2-year-old boy is diagnosed with
meningococcal meningitis. IV penicillin was
administered on admission, droplet precautions
were begun immediately, and he received oral
rifampin the next morning. No special
resuscitative measures were ever required. To
reduce the risk of secondary cases, prophylaxis
with oral rifampin is necessary for:
 A. Physicians who examined the patient
 B. Nurses who delivered routine bedside care
 C. Grandparents who live out of state and visited him
in the hospital
 D. Laboratory personnel who drew blood samples
 E. His companions in child care
Treatment of contacts

*Know that certain close contacts of patients
with N. meningitidis require
chemoprophylaxis
 Household contacts
 Child care or pre-school contact
 Direct exposure to index case’s oral secretions (7
days before onset of illness)
○ Kissing, toothbrushes or utensils, mouth-to-mouth
 Slept in the same dwelling during 7 days before
 Passengers seated directly next to index case on
flight longer than 8 hours
Treatment of Contacts

*Know what to recommend to a parent
when it is reported that a child has been
exposed to meningitis in school
 Low risk
 No history of direct contact to index patient’s
oral secretions
 NO chemoprophylaxis is recommended for
school or work
○ Only child care centers
Treatment of Contacts
Rifampin
 Ciprofloxacin
 Azithromycin
 Ceftriaxone

The Virus
Hepadnavirus family
 HBcAg: protein that
forms the nucleocapsid
that encloses the viral
DNA
 HBeAg: secreted soluble
antigen believed to induce
tolerance
 HBsAg: surface antigen

Epidemiology

One third of the world’s population is
infected (!)
 Endemic areas: Africa, Eastern Europe, the
Middle East, Southeast and Central Asia, the
Pacific Islands, and the Amazon Basin of South
America
Vaccine administration has greatly reduced
disease burden
 *Risk groups

 Injection drug users
 Immigrants from endemic countries
Epidemiology

Transmission
 Virus present to some degree in most body
fluids, but highest concentration is in the
serum
 *Routes of transmission
○ Percutaneous injection of body fluids
○ Sexual contact
○ Perinatal vertical transmission
 *Incubation period: 2-6 mos
 *Period of communicability: higher chance of
transmission when patient is HBeAg+
*Clinical Manifestations

Extrahepatic
 Polyarteritis nodosa
 Membranoproliferative glomerulonephritis
 Leukocytoclastic vasculitis
 Arthalgias/arthritis
 Erythematous or urticarial rash that
precedes hepatic manifestations
*Clinical Manifestations

Hepatic
 Acute self-limited hepatitis
 Acute fulminant hepatitis
 Chronic hepatitis
 Cirrhosis
 Hepatocellular carcinoma
Clinical Manifestations

Acute self-limited hepatitis
 Nausea, fever, abdominal pain, jaundice,
fatigue, general malaise
 Increased transaminases
 Resolution of infection within 6 months
○ HBsAb seroconversion

Acute fulminant hepatitis
 Associated change in mental status brought
on by hepatic encephalopathy
 More common presentation during infancy
Question #12

True or False: Perinatally-acquired HBV
infections are less likely to cause
chronic infections than infections
acquired later in life
 A. True
 B. False
Clinical Manifestations

Chronic HBV infection
 Presence of HBsAg in serum for at least 6
months or presence of HBsAg without IgM
HBcAb
 *The younger a person is exposed, the more
likely he/she will become chronically infected
○ 90% of exposed infants become chronically
infected
○ 25-50% of exposed 1-5yo
○ Only 6-10% of those exposed >5yo
 Usually asymptomatic in childhood
Clinical Manifestations

Chronic HBV infection (con’t)
 Progresses through 3 phases:
○ Immune tolerance
 No liver inflammation
 High viral counts
 HBeAg+
○ Immune clearance
 Increasing liver inflammation (with resulting damage)
 Decreasing viral counts
 HBeAb seroconversion
○ Residual
Clinical Manifestations

Cirrhosis/ HCC
 Up to 25% of children with chronic HBV
infection develop cirrhosis or HCC
 Factors that contribute to risk
○ Race
○ Genotype of the virus
○ Alcohol consumption
○ Coinfection with HCV,
HDV, HAV, or HIV
Question #13

You are reviewing a patient’s HBV serum
markers. You see that the patient’s HBsAb
is positive, along with the total HBcAb. The
HBsAg and the HBcAb IgM are both
negative. Of the following, the most
appropriate interpretation of these labs is:





A. Immune recovery after HBV infection
B. No prior infection, not immune
C. Chronic HBV infection
D. Acute HBV infection
E. Immune after Hep B vaccination
Question #14

You are reviewing yet another patient’s
HBV serum markers. This patient has a
positive HBsAg and total HBcAb, with a
negative HBcAb IgM and HBsAb. Of the
following, the most appropriate
interpretation of these labs is:





A. Immune recovery after HBV infection
B. No prior infection, not immune
C. Chronic HBV infection
D. Acute HBV infection
E. Immune after Hep B vaccination
*Serum Markers
Screening In Chronic HBV
Infections

Liver enzymes
 Q6mos

Serum AFP
 Q6mos

Ultrasound of the liver
 Q12 mos
Treatment

Goal of therapy: long-term remission
(eradication not possible with current
therapies)
 Loss of detectable HBV in the serum
 Loss of HBeAg

Available therapies:
 Interferon
○ Stimulates host immune system to maximize its
own antiviral effect
 Nucleotide/side antivirals (lamivudine)
○ Interferes with the reverse transcription of HBV
Question #15

A 38 wga M is born to a 24 yo G1P0 via NSVD.
Upon review of the maternal labs, you notice that
Mom is HBsAg+. The baby is currently 10h old
and is eating, sleeping, urinating and stooling
normally. Of the following, the most appropriate
course of action in this infant is:
 A. Immediate administration of the Hep B vaccine
 B. Immediate administration of HBIG
 C. Immediate administration of both the Hep B vaccine
and HBIG
 D. Start lamivudine
 E. No interventions are necessary in the infant
Immunoprophylaxis

Two types of therapy:
 HBV vaccine
 HBIG

CDC has set a goal for eliminating
transmission of HBV in the US
 Universal immunization of infants at birth
 Prevention of perinatal HBV transmission via routine
screening of all pregnant woman and appropriate
immunoprophylaxis for exposed infants
 Routine immunization of children and adolescents
that have not been previously immunized
 Immunization of previously unimmunized adults
Thank you for participating in
board review this year!!