TABLE 121.2 Initial Antibiotic Therapy: Septic Arthritis a Age Pathogens Antibiotics Neonate 2 mo–5 yrs >5 yrs Adolescent Clindamycin b , c Clindamycin b , c Clindamycin c and ceftriaxone d a Common pathogens and empiric antibiotic coverage by age ceftriaxone for Gram stain without gram-positive cocci, PCR or culture positive for K kingae, or ill appearance c Vancomycin, if high incidence of clindamycin resistance in community or ill appearance, and consider for all hip and shoulder joints d Empiric treatment in sexually active adolescent b Add Clinical Indications for Discharge or Admission The management of septic arthritis consists of hospitalization, parenteral administration of antibiotics ( Table 121.2 ), and joint immobilization Joint irrigation should be performed in selected cases Empiric antibiotic therapy is dictated by the common organisms in the age group, local sensitivities, and by results of the synovial fluid Gram stain Antibiotic administration should be initiated as soon as blood and synovial cultures have been obtained Vancomycin or clindamycin may be indicated depending on the incidence of clindamycinresistant MRSA in the community; vancomycin should also be considered as part of the antimicrobial regimen for critically ill children Gram-negative coverage should be added in neonates and adolescents A third-generation cephalosporin