Septic arthritis (peds)

Background

• Most often in patients < 3yo
• MSSA and MRSA are most common causes in all age groups
• Patients with sickle cell disease, rheumatoid arthritis, and inflammatory bowel disease are at increased risk

Evaluation

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

Kocher Criteria

• One point each
  • Non-weight bearing on affected side
  • ESR >40mm/hr
  • Fever
  • WBC >12,000
• Probability by points
  • 1 of 4 - 3%
  • 2 of 4 - 40%
  • 3 of 4 - 93%
  • 4 of 4 - 99%

Work-Up

• Labs
  • CBC, ESR, CRP, , blood/throat cultures
• Arthrocentesis
  • Cell count, gram stain, glucose, cultures

Differential Diagnosis

• Trauma
• Septic arthritis
• Acute Rheumatic Fever
• Reactive Arthritis (Poststreptococcal)
• Gonococcal arthritis
• Lyme disease
• Sickle cell crisis
• Henoch-Schonlein Purpura (HSP)
• Legg Calve Perthes Disease
• Slipped Capital Femoral Epiphysis (SCFE)
• Osteomyelitis
• Juvenile Idiopathic Arthritis
• Transient (Toxic) Synovitis (Hip)
• Hemophilia
• Osgood Schlatter Disease

Treatment

1. Joint drainage/wash out
2. IV antibiotics

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

Disposition

Admit

See Also

• Septic Arthritis (General)
• Arthrocentesis