Flashcards in LRT Infections in Kids Deck (55):
Define lower respiratory infection?
any sublaryngeal airway infection is LRT
-inflammation or infection of the lungs - especially the gas exchange units (terminal and respiratory bronchioles and interstitium)
most common cause of pneumonia (a LRT infection) in children (<1 year old?
number 1 cause (organism) of bacterial/pyogenic pneumonia through childhood?
How does pneumonia happen?
-deposition and replication of viral/bacterial agents on resp tract mucosa or the lung can be seeded hematogenously during bacteremia (from the blood to lungs)
How do bacteria often cause pneumonia?
-colonize the respiratory tract
how do viruses cause pneumonia?
-viral infections impair HOST DEFENSES = secondary bacterial pneumonias
ALL MUST WORK
-nasopharyngeal air filtration
-laryngeal protection of the airway
-normal cough reflexes and strength
-unobstructed airway drainage
-normal cellular and humoral immune function
-3 main findings of pneumonia??? -Which symptom is most specific for pneumonia?
-tachypnea --> MOST **SENSITIVE** AND SPECIFIC SIGN OF PNEUMONIA IN INFANTS!
Clinical findings of pneumonia in children on physical exam?
-refusal to eat
-dec breath sounds
-normal breath sounds (less mass so the sounds distribute better throughout chest so may be normal sounding)
-accessory muscle use/retractions
Global health standards for pneumonia if youre out in the world?
need to have tachypnea and retractions to diagnose pneumonia
Bordatella pertusis- info:
-gram NEG pleomorphic
-humans only host
-transmission=droplet from cough
-incubation 6 days
3 phases of whooping cough:
1) catarhal phase
-low grade fever
2) Paroxysmal phase
-2-4 weeks coughing inc in frequency and intensity
-WHOOP** - uncommon in child <6mo
-POST TUSSIVE EMESIS***
-hypoxia and fatigue from constant cough
3) Convalescent phase
-cough and vomit dec in frequency
-cough may continue for weeks
Pertusis testing/lab results
-leukocytosis (HIGH ABS LYMPH COUNT --> DIFFERENT BC THIS ISNT VIRAL BUT LYMPHS ARE UP!!!)
-CXR=perihilar infiltrates, atelectasis or emphysema
-nasopharyngeal swabs for PCR
Pertusis TX in child:
-hospitalize (if infant)
-oxygen & IV fluids
-erythromycin 40mg/kg divided q 6hrs for 14 days
-isolate patient for 5 days to prevent spread
Antibiotic of choice for pertussis in child?
influenza - info
-A, B, and C types - A and B causing epidemics
-H1N1 predominated last year
-H3N2 have greater mortality
Type A influenza surface antigens:
-surface antigens hemagglutinin (HA) and neuraminidase
3 types of hemagglutinin types:
H1 H2 and H3
2 types of neuramidase types:
N1 and N2`
Major changes of hemagglutinin type is called? Minor?
-antigenic shift = major
-antigenic drift = minor
influenza - spread?
influenza - who gets? when?
-school age children
-community outbreaks occur in winter and peak within 2 weeks of onset and last 4-8 weeks
influenza - infectious?
-infectious > 10 days after the onset of symptoms
-severely immunocomp patients shed virus for weeks to months
influenza - symptoms
-1-4 days onset (ABRUPT)
-mimics bacterial sepsis
-coryza (perfuse runny nose)
- dry cough
-can localize anywhere in resp tract = URI, croup, bronchiolitis, pneumonia
most common secondary bacterial infection due to influenza?
-strep pneumo (MOST COMMON)
-staph aureus ( ALSO COMMON)
What is Reye syndrome:
-affects brain and liver post viral (varicella) or influenza infection
Stages of Reye syndrome:
1=vomit, confusion, lethargy
2=agitation, delirium, DECORTICATE (elbows flexed) posturing, hyperventilation
3=coma and DECEREBRATE (elbows extended) posturing
4=flaccidity, apnea, and dilated fixed pupils
Progression from stage 1 to 4 can happen in 24 hours
-worse outcome if younger
What inc risk of Reye syndrome during viral illness?
Diagnosis of reye syndrome:
Definitive diagnosis with?
-inc liver enzymes
Definitive with liver biopsy
Reye syndrome tx?
-correct hypoglycemia and inc ICP
diagnosis of influenza:
-based on clinical presentation, time of year, and community surveillance
-rapid nasal swab tests of Influ A and B
-blood count short normal WBC or mild dec in leukocytes
Tx for influenza?
-supportive most - fluids, fever control, rest
-neuraminidase inhibitors (zanamivir & oseltamivir) in children if bad
Vaccination against influenza?
vaccinate everyone above 6mo
RSV epidemic when?
-resp droplets and fomites
classic finding in RSV?
recovery from RSV how long?
x-ray of RSV?
-inc interstitial markings
-DO NOT ORDER X-RAY
Tx for RSV bronchiolitis
-maintain patency of nasal airway
-maintain adequate hydration and nutrition
-optimize ventilation and oxygenation
Aim of tx of RSV bronchiolitis
-releive resp distress
-overcome airway obstruction
-enhance mucociliary clearance
-return child to normal resp status
tachypnea + rales heard but no wheezing, no fever, 6 weeks old, conjunctivitis - organism?
-chlamydia trachomatis pneumonia
presentation of chlamydia trachomatis?
-1-3 months (NONE OLDER THAN 4mo)****
-repetitive staccato cough, tachypnea, and absence of fever, wheezing some nasal stuffiness
-CXR no sig abnormalities or hyperinflation (shaggy heart sometimes)
-WBC usually normal with peripheral eosinophilia
chlamydia trachomatis - tx:
-macrolides (*ORAL AZITHROMYCIN for 5 days or ORAL ERYTHROMYCIN for 14days)
If there is evidence of chlamydial conjunctivits without pneumonia tx how?**
-still give oral erythromycin**
sudent onset fever to 102.5
hgih WBC count
left shift-inc bands
what organism present similarly?
pneumonia - strep pneumo
(since its not viral strep pneumo is most common)
-influenza similar BUT RARELY has hypoxemia and doesnt have high WBC
CXR of strep pneumo?
-lobar or segmental consolidation
strep pneumo if child is untable symptoms?
-IV antibiotics - ampicillin / sulbactam, cefuroxime, ceftriaxone
-continueuntil patient stable then give 10 day course of oral antibiotics
strep pneumo if child is stable tx?
-->amoxicillin/clavulanic acid, cefuroxime, or other 2nd gen ceph
mycoplasma pneumonia - info
-most common in school age child
-RARE BEFORE AGE 3-4
presumptive diagnosis of m pneumo with what test?
definitive diagnosis of mycoplasma via?
-drawing mycoplasma titers
clinical manifestation of mycoplasma
-intractable nonproductive to mild cough ***
-squeaky door breathing
Tx of choice for mycoplasma?