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Changing bacteriology of periorbital cellulitis
1Department of Emergency Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
Insights
In the post-Haemophilus influenzae type B (HIB) vaccination era, streptococcal bacteria are the primary cause of bacteremic periorbital cellulitis in children. Invasive Haemophilus influenzae infections are now rare, and meningitis is uncommon.
Area of Science:
- Pediatric Infectious Diseases
- Bacteriology
- Vaccinology
Background:
- Periorbital cellulitis traditionally linked to Haemophilus influenzae.
- Standard diagnostic evaluation includes blood culture and CSF analysis for children.
- Impact of Haemophilus influenzae type B (HIB) vaccination on bacteremic periorbital cellulitis is under investigation.
Purpose of the Study:
- To determine the prevalence of H. influenzae bacteremia in pediatric periorbital cellulitis post-HIB vaccination.
- To assess the diagnostic yield of routine cerebrospinal fluid (CSF) analysis in these cases.
Main Methods:
- Retrospective case series of pediatric patients (2 months–17 years) diagnosed with periorbital cellulitis.
- Data collected from 1986–1994 at an urban university referral hospital.
- Chart review to ascertain prevalence of bacteremia and meningitis.
Main Results:
- Of 49 children, 10% had positive blood cultures, predominantly streptococcal species; one H. influenzae case occurred pre-vaccination.
- CSF analysis in 41% of patients revealed no abnormalities or positive cultures.
- Radiographic sinusitis was diagnosed in 19% of patients.
Conclusions:
- Streptococcal species are now the leading cause of bacteremic periorbital cellulitis.
- H. influenzae bacteremia is infrequent following HIB vaccination.
- Meningitis is uncommon, suggesting lumbar puncture may not be routinely necessary for well-appearing children. Sinusitis is common and often underdiagnosed.
Study Objective:
Bacteremic periorbital cellulitis has traditionally been associated with Haemophilus influenzae infection, and the recommended diagnostic evaluation in young children includes blood culture and cerebrospinal fluid (CSF) analysis. The objectives of this study were to examine in pediatric patients with periorbital cellulitis (1) the prevalence of H influenzae bacteremia in the era of vaccination for H influenzae type B (HIB) and (2) the yield of routine CSF analysis.
Methods:
This was a retrospective case series of children aged 2 months to 17 years with a final discharge diagnosis of periorbital cellulitis who were treated from 1986 through 1994 at an urban university referral hospital. The prevalence of bacteremia and meningitis was obtained from chart review.
Results:
Forty-nine children were enrolled, of whom 3 were treated as outpatients. The mean age was 36 months (median, 19 months). A blood culture was obtained for 92% of the patients. Five patients (10%; 95% confidence interval, 3% to 22%) had a positive blood culture (four streptococcal species, one H influenzae). The patient with H influenzae bacteremia was treated in 1987 and had not had the HIB vaccine. CSF was analyzed for 41% of the patients, and none had an abnormal cell count or a positive culture. Sinusitis was diagnosed radiographically in 19% of the subjects.
Conclusion:
Streptococcal organisms are the most common cause of bacteremia associated with periorbital cellulitis in the post-HIB vaccination era. H influenzae bacteremia is now a rare occurrence. Meningitis is uncommon, and lumbar puncture may not be mandatory in well-appearing children. Sinusitis is common and was probably underdiagnosed in our series because most children were not evaluated radiographically. Outpatient management may be indicated in selected children.
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