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ID Part Deux. June Board Review. Test Question. I will watch the summer olympics this year. A. True B. False. Bronchiolitis. Intro. Bronchiolitis is caused by inflammation of the bronchioles by an acute viral infection
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ID Part Deux June Board Review
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 symptomsfollowed 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 pre-K. • 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 4-years-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, 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 (headtoe) 48h 2-3d
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 • Subacutesclerosingpanencephalitis (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 (post-auricular, posterior cervical, and occipital); malaise, HA, low-grade fever, sore throat 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 1-5 d
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
Highest rate of infection 1st and 3rd trimesters, morbidity associated with 1st trimester infection Presentation: Blueberry muffin lesions Radiolucencies in metaphyseal long bones PDA (or ASD/VSD) Sensorineural deafness Cataracts/ glaucoma HSM IUGR *Congenital Rubella
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
Neisseriameningitidis • *Know the epidemiology of Neisseriameningitidis • 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 Neisseriameningitidis • 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 • Purpurafulminans • Aggressive spread of purpura to large areas with iscemic necrosis • Likely to have sudden drops in blood pressure and acute adrenal hemorrhage (Waterhouse-Friderichsen)
*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