Evaluation of arthritis and arthralgia in the pediatric patient.

The records of 250 consecutive children presenting to a university pediatric service with joint complaints of unknown cause were reviewed to determine the frequency of diagnoses and the utility of laboratory data and physical examination findings. Eighteen per cent of children had orthopedic disorders (Group I), 17.6 per cent had autoimmune disorders (Group II), 19.6 per cent had joint complaints related to a bacterial infection (Group III), and 44 per cent had miscellaneous problems (Group IV). Autoimmune or infectious disd/or erythrocyte sedimentation rate was greater than or equal to 30 mm/h was present than if absent (65% vs. 8% respectively); the sensitivity of fever and/or elevated erythrocyte sedimentation rate was 93 per cent for Group II and III patients. The presence of rash was predictive of an autoimmune disorder in 67 per cent of the instances; a positive joint examination was seen disproportionately in Group I patients. A negative joint examination all but ruled out an infectious etiology. Other test results, such as diagnostic radiograms, WBC greater than or equal to 15,000 per cu mm; or a positive ANA or rheumatoid factor were predictive but not sensitive indicators of selected groups. If the tiology of a child's joint complaints is unknown, the likelihood of an orthopedic, autoimmune or infectious disorder may be suggested by reviewing temperature and ESR data and skin and joint findings.