1. Core Tutorial in Pediatric Infectious Diseases for Third Year Medical Students Infectious Disease Emergencies

2. How would you evaluate this patient?
A sixteen-year-old girl presents with fever and lower abdominal pain but denies urinary urgency or frequency. She is sexually active and uses condoms infrequently.

3. How would you evaluate this patient?
A sixteen-month-old presents with a history of nasal discharge for the past week presents with a swollen, red eye and fevers to 1030 F.

4. Learning Objectives
Be able to recognize an infectious disease emergency
Understand the age-appropriate approach to diagnosis and initial management of infectious disease emergencies
Be familiar with various agents with bioterrorism potential

5. Bacteremia and Sepsis
Bacteremia = Presence of pathogenic bacteria in the blood of mildly or moderately ill child
Incidence peak at age 6 to 18 months
See “Fever” tutorial for complete discussion of work-up and management
Sepsis = Bacteremia with serious systemic illness
Pathogens
birth to 2 months: Group B Streptococcus, E. coli
older infants: Strep. pneumoniae, N. meningitidis, Group A Streptococcus, S. aureus, Salmonella
Risk factors
neoplasia, immunodeficiency syndromes, immunosuppressive therapy, asplenia, sickle cell disease

6. Sepsis Signs and Symptoms Work-up Treatment
fever, tachycardia, tachypnea, hypotension, metabolic acidosis, thrombocytopenia, leukocytosis (leukopenia with overwhelming infection)
Work-up
CBC
blood culture
coagulation studies, electrolytes, LFT’s, BUN and creatinine
Treatment
fluids, vasopressors; close monitoring in ICU
age < 2 months: ampicillin and gentamicin or cefotaxime
age > 2 months ceftriaxone or cefotaxime +/- vancomycin

7. Meningococcemia Neisseria meningitidis
Peak incidence is first year of life, 40% in age < 5 yrs
Risk factors include overcrowding, poverty, cigarette smoke exposure, prior respiratory infection, congenital impairment of phagocytosis
Transmission by respiratory droplets, close direct contact
Endotoxin (lipopolysaccharide) causes endothelial damage, systemic inflammatory response
Can progress from asymptomatic to death within hours

8. Meningococcemia, con’t
Signs and symptoms
Fever, headache, myalgias
Altered mental status , high fever or hypothermia, tachypnea, hypotension
Petechial rash progressing to purpura may begin as macules, maculopapules, or urticaria
Case fatality rate > 40%
Work-up
Culture blood, CSF, skin lesions
CSF antigen testing (latex agglutination)

9. Meningococcemia, con’t
Treatment
Penicillin G if susceptible (most are but start with third generation cephalosporin until sensitivities are known)
Supportive care
Prevention
chemoprophylaxis of contacts
rifampin, ceftriaxone, ciprofloxacin
vaccine
A/C/Y/W135

10. Meningitis Incidence peak at age 6 to 24 months
Cerebrospinal fluid normal values vary with age
Meningeal signs (neck stiffness, Kernig’s sign and Brudzinski’s sign) may be absent in young infants
Most common bacterial pathogens vary with age:
Neonate: Group B Strep, E. coli, L. monocytogenes
Older infants and children: S. pneumoniae, N. meningitidis, H. influenzae

11. Meningitis, con’t
Colonization (nasopharynx) resulting in bacteremia can lead to hematogenous seeding of meninges; also can have direct extension from a parameningeal focus (i.e., sinusitis)
Work-up
CBC, electrolytes, BUN, creatinine, glucose, coagulation studies
blood culture
CSF analysis: cell counts, protein, glucose, gram stain and culture,
Management
ABC’s, monitoring
supportive care
age < 1 month: ampicillin and cefotaxime
age > 1 month; vancomycin and ceftriaxone or cefotaxime

12. Other CNS Infections Encephalitis
viral, bacterial, post-infectious, non-infectious
treatment depends on etiology
Subdural empyema
immediate surgical drainage
Brain abscess
antibiotics, steroids
management of elevated intracranial pressure
frequently requires surgical drainage
Orbital cellulitis
I.V. antibiotics and frequent evaluation by ophthalmologist with consideration of surgical drainage

13. Epiglottitis
Common etiology was H. influenzae type b prior to the introduction of vaccine
Other etiologies: Strep. pneumoniae, Strep. pyogenes, Staph. aureus
Incidence was highest in age 3 to 6 years but with vaccine incidence has declined dramatically
Presentation is toxic-appearing child with fever, drooling, stridor, tachycardia, tachypnea, and a preference for sitting up leaning forward
This is a true emergency and can progress rapidly to complete airway obstruction especially if the child is disturbed
If epiglottitis is suspected priority is control of the airway before any other intervention or diagnostic evaluation

14. Epiglottitis, con’t
Infection leads to edema of epiglottis, spreads to aryepiglottic folds, arytenoids, and entire supraglottic larynx
Work-up and treatment after securing airway
Work-up
WBC (leukocytosis with left shift)
blood culture
epiglottis culture
lateral neck film (“thumb sign”)
Treatment
ceftriaxone or cefotaxime
close observation in ICU

15. Bacterial Tracheitis
Bacterial complication of viral laryngotracheobronchitis
Pathogens: Staph aureus, Strep pyogenes, H. influenzae, Strep pneumoniae; rarely M. catarrhalis, anaerobes
As viral infection wanes, abrupt worsening of symptoms with new fever and stridor
Toxic-appearing, agitated
Priority is establishment of an artificial airway
Work-up and management: see Epiglottitis

16. Retropharyngeal Abscess
Potential space between anterior border of cervical vertebrae and posterior wall of esophagus
Group A Strep, anaerobes, Staph. aureus
Age < 4 years more common
Fever, toxic-appearance, stridor, drooling, meningismus
Lateral neck film or CT
Risk of airway obstruction
Treatment: Clindamycin or penicillin and cefazolin; drainage

17. Septic Arthritis
Presentation is systemic illness with fever and refusal to use joint
Exam reveals warmth, swelling, tenderness, and limited passive range of motion
Usual etiology is hematogenous seeding of synovial tissue
May also result from extension of osteomyelitis
Most are monoarticular
Boys more commonly affected than girls
Bacterial etiologies: Staph. aureus, Strep. pneumoniae, Strep. pyogenes, H. influenzae (also Group B Strep and gram-negatives in neonates; N. gonorrheae in adolescents)

18. Septic Arthritis, con’t
Work-up
CBC (leukocytosis with left shift)
ESR
joint fluid analysis (WBC, glucose, culture)
blood culture
Treatment
hip: immediate surgical drainage
age birth to 2 months: oxacillin and gentamicin
2 months to 3 years: cefotaxime, ampicillin/clavulanate
3 to 12 years: oxacillin
adolescents: ceftriaxone

19. Toxic Shock Syndrome
Staphylococcus aureus of phage group I that produces epidermal toxin, toxic shock syndrome toxin-I (TSST-I)
Also toxin-producing Streptococcus pyogenes
Presenting signs/symptoms: fever, hypotension, erythrodermatous sunburnlike rash with subsequent desquamation of palms and soles, multiorgan system involvement (diarrhea, vomiting, myalgias, azotemia, hepatitis, thrombocytopenia, change in mental status)
Treatment includes fluid resuscitation, vasopessors, intensive care monitoring, antibiotics
Mortality due to cardiac arrhythmias, respiratory failure, bleeding

20. Appendicitis Most common pediatric abdominal surgical emergency
Polymicrobial with enteric flora
Age > 5 years (peak years)
Perforation in one-third of cases; more common in age < 6 years
Mid-abdominal pain initially, then RLQ pain
Fever, anorexia, nausea, vomiting, rebound tenderness
Psoas and obturator signs
Elevated WBC
Imaging modalities most helpful U/S and CT scan

21. Appendicitis, con’t
IV antibiotics directed against gram negatives and anaerobes
Antibiotics prior to surgery
Complications: peritonitis, abscess, wound infection, multiorgan failure, hernia, adhesions, death

22. Biological Terrorism Features of a potential bioterrorism event
multiple patients with same symptoms
severe illness among young, previously healthy
unusual organisms
unusual antibiotic resistance patterns
atypical presentations
unusual patterns of disease (geographic clustering)
intelligence information
sick or dead animals or plants
adapted from Annals of Emergency Medicine 1999;34:183-90

23. Biological Terrorism, con’t
Biological agents (highest priority per CDC)
Smallpox
Bacillus anthracis (anthrax)
Yersinia pestis (plague)
Clostridium botulinum toxin (botulism)
Francisella tularensis (tularemia)
Filoviruses
Ebola and Marburg hemorrhagic fevers
Arenaviruses
Lassa (Lassa fever), Junin (Argentine hemorrhagic fever)

24. Biological Terrorism Click to link to the CDC web site
on biological terrorism

25. References
Fleisher GR and Ludwig S, eds. Textbook of Pediatric Emergency Medicine, Fourth Edition. Lippincott Williams and Wilkins, 2000.
Reece RM, ed. Manual of Emergency Pediatrics, Fourth Edition. W. B. Saunders Company, 1992.
Centers for Disease Control and Prevention. Biological and chemical terrorism: strategic plan for preparedness and response. Morbidity and Mortality Weekly Report 2000;49(RR-4).
Richards CF, et al. Emergency physicians and biological terrorism. Annals of Emergency Medicine 1999;34:

26. Questions for Discussion
1 of 8 ?
Questions for Discussion
A sixteen-year-old girl presents with fever and lower abdominal pain but denies urinary urgency or frequency. She is sexually active and uses condoms infrequently.
How would you evaluate this patient?

27. 2 of 8 ?
Questions, con’t
A sixteen-month-old presents with a history of nasal discharge for the past week presents with a swollen, red eye and fevers to 1030 F.
What are you most concerned about?
How would you evaluate this patient?

28. 3 of 8 ?
Questions, con’t
A fourteen-year-old male presents with six hours of severe abdominal pain that is now more right sided. He has had no diarrhea.
How would you evaluate this patient?
How would your approach differ if the patient were a girl?

29. 4 of 8 ?
Questions, con’t
A 14-month-old girl presents with the sudden onset of fever and refusal to walk.
Discuss your differential diagnosis and evaluation of this child.

30. ? Questions, con’t A five-year-old presents with a swollen, red knee.
5 of 8 ?
Questions, con’t
A five-year-old presents with a swollen, red knee.
Discuss your differential diagnosis and evaluation of this child.

31. 6 of 8 ?
Questions, con’t
A three-year-old child presents to the Emergency Department with acute onset of stridor and tachypnea.
Discuss your approach to this patient, including important aspects of the history and physical exam, the differential diagnosis, and management principles.

32. 7 of 8 ?
Questions, con’t
A four-month-old baby presents to the Emergency Department with a fever of 1040 F and petechiae.
What is your differential diagnosis?
How would you evaluate and manage this patient?

33. Questions, con’t
8 of 8 ?
A previously healthy 14-month-old presents to the Emergency Department following 2-3 minutes of generalized, symmetric tonic-clonic movements.
Discuss your approach to the following scenarios:
(a) The child was sleepy initially but is now awake, alert and easily consoled by her parents. Her temperature is 104 F.
(b) The child remains somnolent and appears to have nuchal rigidity.