Acute-phase reactants and acute bacterial otitis media
M. A. Del Beccaro, P. M. Mendelman, A. F. Inglis, M. A. Richardson, N. O. Duncan and R. P. Shugerman
Emergency Services, Children's Hospital and Medical Center, Seattle, WA 98105.
OBJECTIVE--To determine if the erythrocyte sedimentation rate and
C-reactive protein level are elevated in uncomplicated acute bacterial
otitis media. DESIGN--Investigator-blinded, antibiotic efficacy trial.
SETTING--The emergency department of an urban regional children's hospital
with 24,000 annual visits. PARTICIPANTS--Thirty-one children with symptoms
of acute bacterial otitis media of 7 days' duration or less. SELECTION
PROCEDURE--Volunteer sample. INTERVENTIONS--Tympanocentesis, oral
antibiotics for 10 days, and three follow-up visits in the next 30 days.
MEASUREMENTS/RESULTS--The erythrocyte sedimentation rate and C-reactive
protein level were obtained at time of entry into the antibiotic study.
Seventeen patients (55%; 95% confidence interval, 37% to 72%) had either an
erythrocyte sedimentation rate above 20 mm/h or a C-reactive protein level
above 8 mg/L. Eleven patients (35%) had a recurrent episode of acute
bacterial otitis media during the follow-up period. The relative risk of
recurrence of otitis media given an elevated erythrocyte sedimentation rate
or C-reactive protein level was 8.24 (95% confidence interval, 1.20 to
56.74; Fisher's Exact Test; P = .007). CONCLUSIONS--Clinicians who use
elevated acute-phase reactants as possible indicators of invasive bacterial
infections should be aware that an elevated erythrocyte sedimentation rate
or C-reactive protein level is also consistent with acute bacterial otitis
media. An elevated erythrocyte sedimentation rate or C-reactive protein
level also appears to be associated with an increased risk of recurrence of
acute bacterial otitis media. If these findings can be confirmed in a
larger study, the erythrocyte sedimentation rate or C-reactive protein
level could be used to assess the risk of recurrent otitis media.
