Septic arthritis (peds)

Background

• Most often in pts <3yo
• MSSA and MRSA are most common causes in all age groups
• Pts w/ SCD, RA and IBD at increased risk

Diagnosis

• Neonates
  • Do not appear ill
  • Only 50% have fever
• Older infants, toddlers, children
  • Fever (>101.3), localizing signs
• Labs
  • CRP >20
  • WBC >12K

Work-Up

• Labs
  • CBC, Blood cx, ESR, CRP, Throat cx
• Arthrocentesis
  • Cell count, GS, glucose, cx

DDx

1. Reactive or toxic synovitis
2. Trauma
3. Septic arthritis
4. Acute rheumatic fever
5. Poststreptococcal reactive arthritis
6. Gonococcal arthritis
7. Lyme disease
8. Sickle cell crisis
9. Henoch-Schönlein purpura
10. Legg-Calvé-Perthes disease
11. Slipped capital femoral epiphysis
12. Osteomyelitis
13. Juvenile rheumatic arthritis
14. Transient synovitis
15. Hemophilia
16. Osgood-Schlatter disease

Treatment

Age	Suspected Organism	Antibiotics
Newborn (0–2 mo)	Staphylococcus aureus	Vancomycin, 10 milligrams/kg every 6–8 h
		or
		Clindamycin, 10 milligrams/kg every 6–8 h
	Group B Streptococcus	Ampicillin, 50–100 milligrams/kg every 6 h
		and
		Cefotaxime, 50 milligrams/kg every 6–8 h
		or
		Ceftriaxone, 50 milligrams/kg every 12 h
	Gram-negative bacilli	Cefotaxime, 50 milligrams/kg every 8 h
	Neisseria gonorrhoeae	Cefotaxime, 50 milligrams/kg every 8 h
	Unknown	Vancomycin or clindamycin and cefotaxime or ceftriaxone (dosing as above)
Infant (2–36 mo)	S. aureus	Vancomycin or clindamycin (dosing as above)
	Streptococcus species	Clindamycin/cefotaxime/ceftriaxone (dosing as above)
	Gram-negative bacilli	Cefotaxime or ceftriaxone (dosing as above)
	Haemophilus influenzae	Cefotaxime or ceftriaxone (dosing as above)
	Unknown	Vancomycin or clindamycin and cefotaxime or ceftriaxone
Child (>36 mo)	S. aureus	Vancomycin or clindamycin
	Streptococcus species	Clindamycin/cefotaxime/ceftriaxone
	Gram-negative bacilli	Cefotaxime or ceftriaxone
	N. gonorrhoeae	Cefotaxime or ceftriaxone
	Unknown	Vancomycin or clindamycin and cefotaxime or ceftriaxone

Source

Tintinalli