EVALUATION OF THE ERYTHROCYTE SEDIMENTATION-RATE IN CHILDREN PRESENTING WITH LIMP, FEVER, OR ABDOMINAL-PAIN

An erythrocyte sedimentation rate (ESR) is commonly ordered as part of the evaluation of patients with nonspecific but potentially serious s ymptoms. To investigate the performance of ESR in this setting, we use d a computerized database and medical chart review to identify childre n (n = 299) with ESR done for a previously undiagnosed condition. Medi cal records were reviewed to determine symptoms at presentation, refer ral status, and subsequent diagnoses, which were classified as serious (n = 93) or benign (n = 206). We found that serious underlying diseas e was about 7 times as likely in patients with ESR>50 mm/hr (57/102) t han in patients with ESR<20 mm/hr (7/89), Although the prevalence of s erious disease was higher among referral patients, the likelihood rati os were similar for referral and primary-care patients. An erythrocyte sedimentation rate greater than 50 mm/hr was most informative in pati ents presenting with limp (likelihood ratio [LR] = 8.2) and abdominal pain (LR = 6.0) and least informative in patients presenting with feve r (LR = 2.5). On the other hand, an ESR<20 mm/hr is reassuring in pati ents presenting with fever (LR = 0) or limp (LR = 0.3), but not in pat ients presenting with abdominal pain (LR = 0.8). An ESR between 20 and 50 mm/hr (23% of the patients) provided little information (LR 1.2-1. 5) in each of the three groups. These results suggest that the ESR oft en provides useful information about the likelihood of serious illness among children presenting with worrisome but nonspecific symptoms, in particular in patients presenting with limp.