Microbiology of Pediatric Orbital Cellulitis and Trends in Methicillin-Resistant Staphylococcus aureus Cases

Microbiology and Epidemiology of Orbital Cellulitis in Pediatric and Young Adult Patients

INTRODUCTION

Using data from the large and geographically diverse Military Health System (MHS) beneficiary population, we aimed to characterize and update the epidemiology and microbiology of pediatric orbital cellulitis given previous data are limited to small, single-center studies.

MATERIALS AND METHODS

Following institutional review board approval, we performed a retrospective analysis using the Military Health System admissions, microbiology, and pharmacy data between June 2009 and September 2019. Patients less than 22 years of age with radiological confirmation of orbital cellulitis were included. Demographic data, presence of sinusitis, advanced imaging reports, blood and wound culture results with antibiotic susceptibilities, and antibiotic prescriptions were collected. Descriptive statistics were used to summarize demographic characteristics. Imaging findings were grouped by Chandler's stage (CS), an imaging-based measure of the progressive severity of orbital involvement. A Cochran-Armitage trend test was used to evaluate the relationship between CS and likelihood of positive confirmatory culture.

RESULTS

There was a male predominance (66.9%) and 55.5% of subjects had comorbid sinusitis. Of the 130 subjects included, 33.8% had one or more positive cultures, 30.8% had a positive wound culture, and 4.6% had a positive blood culture. The most identified organism was coagulase-negative staphylococci (23.3%), followed by Staphylococcus aureus (18.9%), Streptococcus intermedius (17.8%), and strict anaerobes as a group (13.3%). Gram-negative organisms were rare. Twenty-five percent of S. aureus were methicillin-resistant. Clindamycin resistance was identified in 9% of all S. aureus, 50% of coagulase-negative staphylococci, and 25% of S. intermedius. Clindamycin plus ceftriaxone was the most prescribed empiric antibiotic regimen (36.2%). Likelihood of a positive culture significantly increased with advancing CS.

CONCLUSIONS

Orbital cellulitis occurs most frequently in males with sinusitis. Likelihood of positive wound culture is increased with a more advanced CS. Staphylococcus and Streptococcus spp. and anaerobes are the most identified pathogens in orbital cellulitis, while gram-negative organisms are rare. Empiric antibiotic selection should include an anti-methicillin-resistant S. aureus agent combined with a broad-spectrum beta-lactam and anaerobic coverage.

Association of empiric antibiotic selection and clinical outcomes in hospitalised children with severe orbital infections: a retrospective cohort study

OBJECTIVE

To determine the association of initial empiric antibiotic regimens with clinical outcomes in hospitalised children with severe orbital infections.

DESIGN

Multi-centre observational cohort study using data from 2009 to 2018 clinical records.

SETTING

Canadian children's hospitals (7) and community hospitals (3).

PATIENTS

Children between 2 months and 18 years hospitalised for >24 hours with severe orbital infections.

INTERVENTIONS

Empiric intravenous antibiotic regimen in the first 24 hours of hospitalisation.

MAIN OUTCOME MEASURES

Length of hospital stay and surgical intervention using multivariable median regression and multivariate logistic regression, with adjustment for covariates.

RESULTS

Of 1421 patients, 60.0% were male and the median age was 5.5 years (IQR 2.4-9.9). Median length of stay was 86.4 hours (IQR 56.9-137.5) and 180 (12.7%) received surgical intervention. Patients receiving broad-spectrum empiric antibiotics had an increased median length of stay, ranging from an additional 13.8 hours (third generation cephalosporin and anaerobic coverage) to 19.5 hours (third generation cephalosporin, staphylococcal and anaerobic coverage). No antibiotic regimen was associated with a change in the odds of surgical intervention. These findings remained unchanged in sensitivity analyses restricted to more severely ill patients. There was a twofold increase in the percentage of patients receiving the broadest empiric antibiotic regimens containing both staphylococcal and anaerobic coverage from 17.8% in 2009 to 40.3% in 2018.

CONCLUSIONS

Empiric use of broad-spectrum antibiotics with staphylococci and anaerobic coverage was associated with longer length of stay and similar rates of surgery in children with orbital infections. There is an urgent need for comparative effectiveness studies of various antibiotic regimes.

Subperiosteal and Orbital Abscesses: A Comparison of Clinical Features, Management, and Outcomes

PURPOSE

To compare the clinical features, management, and outcomes between orbital cellulitis patients with subperiosteal abscess (SPA) and those with orbital abscess (OA).

METHODS

A retrospective study was conducted at a tertiary care center through medical record search to identify patients with orbital cellulitis from January 1, 2000 to December 31, 2022. Charts were screened for those with radiographic evidence of SPA or OA. Demographic data and presenting clinical features were compared between the 2 cohorts. Primary outcomes compared included rates of surgical intervention, reoperation, and readmission; and length of hospital stay and final vision.

RESULTS

A total of 189 patients, 162 with SPA and 27 with OA, met the criteria. The OA group (mean 46.5 ± 18.6 years) was older than the SPA group (mean 19.1 ± 21.4 years). Comorbid sinusitis was significantly more common in the SPA cohort (95.7% SPA; 70.4% OA; p < 0.001), while OA was more likely to occur with orbital trauma (29.6% vs. 8.0%; p = 0.003), implanted hardware (11.1% vs. 0.6%; p = 0.005), and comorbid diabetes (22.2% vs. 4.3%; p = 0.001). OA patients more often presented with a relative afferent pupillary defect (21.7% vs. 3.9%; p = 0.005), vision worse than 20 of 50 (42.3% vs. 16.2%; p = 0.005), and methicillin-resistant Staphylococcus aureus infection (20.8% vs. 5.8%; p = 0.036). OA was associated with a higher reoperation rate (47.8% vs. 21.3%; p = 0.019), readmission rate (18.5% vs. 5.6%, p = 0.047), and limited extraocular motility at follow-up (4.3% vs. 25%; p = 0.013); while mean length of hospital stay and final visual acuity were similar.

CONCLUSION

OA may affect an older population with a divergent risk factor profile compared with SPA. OA may cause more severe functional impairment on presentation, warranting more aggressive management to achieve visual outcomes similar to SPA.

Bugs Behind the Bulging Eyeball: Microbiology and Antibiotic Management in Orbital Cellulitis With or Without Subperiosteal Abscess

The objective of this study is to describe causative pathogens and current antibiotic management among hospitalized children with orbital cellulitis. This retrospective study, performed at a tertiary care children's health system, included patients up to 18 years old who presented with radiographic evidence of orbital cellulitis from 2012 to 2019. Of the 298 patients included in the study, 103 had surgery and an intraoperative culture obtained. A pathogen was recovered in 86 cultures (83.5%). The most common pathogens were Streptococcus anginosus group (26.2%), Streptococcus pyogenes (11.7%), methicillin-susceptible Staphylococcus aureus (10.7%), and Streptococcus pneumoniae (9.7%). Only 8/194 (4.1%) blood cultures returned positive. Median duration of intravenous antibiotics was 4 days and median total duration was 17 days. The most common empiric regimen prescribed was ceftriaxone and clindamycin (64.1%). Despite low incidence of methicillin-resistant S aureus, empiric antibiotics often consisted of 2 antibiotics to ensure coverage for this bacterium.

Methicillin-resistant Staphylococcus aureus-associated orbital cellulitis: a case series

PURPOSE

In recent years, methicillin-resistant Staphylococcus aureus (MRSA) orbital cellulitis (OC) has drawn increasing clinical and public health concern. We present a case series of MRSA OC encountered at four Australian tertiary institutions.

METHODS

A multi-centre retrospective case series investigating MRSA OC in Australia from 2013 to 2022. Patients of all ages were included.

RESULTS

Nine cases of culture-positive non-multi-resistant MRSA (nmMRSA) OC were identified at four tertiary institutions across Australia (7 male, 2 female). Mean age was 17.1 ± 16.7 years (range 13-days to 53-years), of which one was 13 days old, and all were immunocompetent. Eight (88.9%) patients had paranasal sinus disease, and seven (77.8%) had a subperiosteal abscess. Four (44.4%) had intracranial extension, including one (11.1%) case which was also complicated by superior sagittal sinus thrombosis. Empirical antibiotics, such as intravenous (IV) cefotaxime alone or IV ceftriaxone and flucloxacillin, were commenced. Following identification of nmMRSA, targeted therapy consisting of vancomycin and/or clindamycin was added. Nine (100%) patients underwent surgical intervention. Average hospital admission was 13.7 ± 6.9 days (range 3-25 days), with two patients requiring intensive care unit (ICU) admission due to complications related to their orbital infection. All patients had favourable prognosis, with preserved visual acuity and extraocular movements, following an average follow-up period of 4.6 months (range 2-9 months).

CONCLUSION

NMMRSA OC can follow an aggressive clinical course causing severe orbital and intracranial complications across a wide demographic. However, early recognition, initiation of targeted antibiotics and surgical intervention when required can effectively manage these complications and achieve favourable visual outcomes.

Microbiology of bacterial orbital cellulitis-tertiary institutional experiences in South Australia: a multi-centre retrospective study

PURPOSE

This study describes the microbiology of bacterial orbital cellulitis (OC) over an 11-year period and its clinical associations at three tertiary institutions in Adelaide, South Australia.

METHODS

Multi-centre retrospective study of the microbiology of bacterial OC between January 2012 and August 2022. Pre-septal cellulitis was excluded. Differences in means were determined by the Independent Samples t-test, and categorical data was analysed via Pearson's Chi square. A P-value < 0.05 was statistically significant.

RESULTS

99 patients (male: 69, mean age: 22.0 ± 23.8 years old), of which 70.7% were aged ≤ 18 years. Sinus and orbital abscess cultures had the greatest positive yield (73.7%). Frequency of organisms: Streptococcus species (34.3%), Staphylococcus aureus (28.3%), Haemophilus species (5.1%), mixed anaerobes (3.0%), Enterobacter cloacae (2.0%), Moraxella catarrhalis (1.0%), Pseudomonas aeruginosa (1.0%), Corynebacterium species (1.0%), Klebsiella pneumoniae (1.0%), Proteus mirabilis (1.0%), Citrobacter koseri (1.0%), and Enterococcus species (1.0%). Streptococcus species predominated in the paediatric population, with a statistically significant difference in mean age between Streptococcus species and Staphylococcus aureus (14.1 ± 16.5 vs 27.6 ± 24.6 years old, respectively) (P = 0.028). No organism was cultured in 32.3% of cases. Methicillin-resistant Staphylococcus aureus (MRSA) accounted for 28.6% of all Staphylococcus aureus isolates, with 50% occurring between 2021 and 2022.

CONCLUSION

Yearly microbiological trends have remained largely constant in South Australia. The causative organism was not identified in 32.3% of cases, further emphasising appropriate empirical antibiotics, and obtaining microbiology from various sources. MRSA OC remains of increased clinical and public health concern and may be associated with a more aggressive disease course.

Epidemiology and Management of Orbital Cellulitis in Children

BACKGROUND

The epidemiology of orbital cellulitis likely has evolved due to the emergence of methicillin-resistant Staphylococcus aureus (MRSA) and the adoption of pneumococcal conjugate vaccination. In the absence of published guidelines, management is highly variable. We characterized epidemiology and management over an 11-year period.

METHODS

A retrospective cohort study of children 0 to 21 years of age with orbital cellulitis +/- subperiosteal orbital abscess hospitalized at a large quaternary children's hospital from January 2008 to June 2018. We reviewed charts for demographic characteristics, clinical features, management, and outcomes. Using multivariable logistic regression, we evaluated predictors of surgical intervention and assessed whether corticosteroid use or antibiotic duration was related to clinical outcomes.

RESULTS

Among 220 patients, methicillin-susceptible S. aureus was the most common organism (26.3%), with MRSA found in only 5.0%. Rates of vancomycin use fluctuated annually from 40.9% to 84.6%. Surgery was performed in 39.5% of the patients. Corticosteroids, used in 70 patients (32.1%), were unrelated to treatment failure (n = 9), defined as persistent signs and symptoms or initial clinical improvement followed by worsening (P = .137). The median antibiotic duration was 17 days (interquartile range 14-26). After controlling for age, gender, proptosis, eye pain with movement, eyelid swelling, neutrophil count, and corticosteroid use, treatment failure was not significantly associated with receipt of ≥ 3 weeks of antibiotic therapy (8/84, 9.5%) compared with > 2 but < 3 weeks (0/51, 0.0%) or ≤ 2 weeks (1/85, 1.2%) (adjusted odds ratio = 5.83 for ≥ 3 vs ≤2 weeks; 95% confidence interval: 0.58, 59.0).

CONCLUSIONS

Although MRSA was rare, empiric vancomycin use was high. Treatment failure was uncommon in patients who received ≤ 2 weeks of therapy, suggesting that shorter durations are adequate in some patients.

Management of periorbital cellulitis at the Pediatric Emergency Department: A ten years study

Periorbital cellulitis is a diagnostic and therapeutic emergency, jeopardizing the prognosis for vision and survival.

PURPOSE

The goal of this study was to analyze the epidemiological and therapeutic features and outcomes of periorbital cellulitis cases treated in the pediatric emergency department.

PATIENTS AND METHODS

A retrospective study including all the children aged between 1 month and 15 years treated for periorbital cellulitis in the Pediatric Emergency Department of the Mohamed VI University Teaching Hospital in Marrakech over a period of 10 years (January 1, 2010-December 31, 2019).

RESULTS

In all, 168 cases of periorbital cellulitis were recorded, with an increasing of the number of cases, from 2 in 2010 to 39 in 2019. The most affected age bracket was the group under 5 years of age (62.5%). The most frequent mode of entry was sinusitis (22%). Preseptal cellulitis was most common (76.7%). The main clinical signs found in orbital cellulitis were proptosis (64%) and chemosis (35.8%), versus conjunctival hyperemia (78%) in preseptal cellulitis. Ophthalmoplegia was present in two cases of orbital cellulitis. The right side was most affected (44%). An orbital CT scan was performed in all cases in our study, showing preseptal cellulitis in 129 patients (76.7%), orbital cellulitis in 14 cases (8.3%), subperiosteal abscess in 20 cases (12%) and orbital abscess in 5 cases (3%). Prior treatment with non-steroidal anti-inflammatory medication was noted in 6%. The most commonly used antibiotic was amoxicillin-clavulanic acid. Steroid treatment was prescribed in 6% of cases. Surgical treatment was indicated in 12 patients (7.1%). The mean hospital length of stay was 3 days for the preseptal cases and 8 days for the orbital cases. All patients had good outcomes with medical and/or surgical treatment. With follow-up of over one year, no complications were noted.

CONCLUSION

The majority of our cases had positive outcomes, highlighting the advantage of early diagnosis, adapted antibiotic treatment and multidisciplinary care, rendering surgery rarely necessary.

Microbiological profile and antibiotic susceptibility trends in orbital cellulitis in India: an analysis over 15 years

PURPOSE

To report the microbiologic profile and antibiotic susceptibility trends in orbital cellulitis.

METHODS

Retrospective review of microbiology records of orbital cellulitis between 2005 and 2019. Orbital pus or conjunctival swab underwent culture for bacteria and fungi and antibiotic susceptibility testing for bacterial isolates. The microbiological profile and trends in antibiotic susceptibility were analyzed over the three study periods: 2005-2009, 2010-2014, and 2015-2019.

RESULTS

Of the 203 patient samples, 189 (93%) were orbital pus samples, and 146 (72%) were culture positive. Organisms included bacteria (167/203, 82.3%), fungi (13/203, 6.4%), and mixed infection (25/203, 10.3%). Among bacteria, 79% were gram positive, with Staphylococcus aureus and Streptococcus species being commonest, and 21% were gram negative, with Pseudomonas aeruginosa and Enterobacteriaceae group being the commonest. Aspergillus flavus was the most common fungus isolated. Trend analysis revealed no change in the number of sterile cases and fungal cellulitis. Increase in gram positive bacteria was statistically significant (p = .0002) between 2005-2009 and 2015-2019. The increase in gram negative bacteria was statistically significant (p = .047) between all three time periods. Susceptibility patterns showed increasing trend of resistance to fluoroquinolones, that reached statistical significance for Ciprofloxacin, Moxifloxacin and Gatifloxacin (p < .05). Sterile sample was not found in any of the pediatric (0-16 years) cases (n = 55), compared to 28% in adults.

CONCLUSION

There was a significant rise in gram positive and negative orbital infections over the 15 year period, with increased resistance to fluoroquinolones. Fungal cellulitis and sterile samples showed a steady trend. Orbital aspirate provides accurate detection of the causative organism.

Evaluation and Medical Management of the Pediatric Patient With Orbital Cellulitis/Abscess: A Systematic Review

BACKGROUND AND OBJECTIVES

Pediatric orbital cellulitis/abscess (OCA) can lead to vision loss, intracranial extension of infection, or cavernous thrombosis if not treated promptly. No widely recognized guidelines exist for the medical management of OCA. The objective of this review was to summarize existing evidence regarding the role of inflammatory markers in distinguishing disease severity and need for surgery; the role of imaging in OCA evaluation; and the microbiology of OCA over the past 2 decades.

METHODS

This review was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Searches were performed in MEDLINE (Ovid), Web of Science Core Collection, Scopus, CINAHL (EBSCO), and Cochrane Central Register of Controlled Trials (CENTRAL), most recently on February 9, 2021.

RESULTS

A total of 63 studies were included. Most were descriptive and assessed to have poor quality with high risk of bias. The existing publications evaluating inflammatory markers in the diagnosis of OCA have inconsistent results. Computed tomography imaging remains the modality of choice for evaluating orbital infection. The most common organisms recovered from intraoperative cultures are Streptococcus species (Streptococcus anginosus group, group A Streptococcus, and pneumococcus) and Staphylococcus aureus. Methicillin-resistant S aureus in culture-positive cases had a median prevalence of 3% (interquartile range, 0%-13%).

CONCLUSION

This systematic review summarizes existing literature concerning inflammatory markers, imaging, and microbiology for OCA evaluation and management. High-quality evidence is still needed to define the optimal medical management of OCA.

Lesion-Mapping Software for the Measurement of Subperiosteal Abscess Volume for Pediatric Orbital Cellulitis: A Retrospective Chart Review

Introduction

Our objective was to assess the utility of using lesion-mapping software to calculate precise orbital volumes to predict patients who would benefit from early surgical intervention.

Methods

We retrospectively reviewed patients diagnosed with subperiosteal orbital abscess (SPOA) secondary to sinusitis at a tertiary pediatric hospital from 2005 to 2016. Diagnoses were confirmed by CT scans. Lesion-mapping software was used to measure SPOA volume using initial CT images. Data collected included patient demographics, length of hospital stay, and subsequent medical or surgical treatment.

Results

Thirty-three (52%) patients ultimately underwent surgical intervention, while 30 (48%) were managed medically. Between the surgical and medical groups, there were no differences in gender, age, or comorbidities. The surgical group had larger abscess volumes than the medically managed group (0.94 mL vs. 0.31 mL, p < 0.01). Overall, increased SPOA volume was associated with increased age (Pearson’s coefficient = 0.374, p ≤ 0.01) and increased total days of intravenous (IV) antibiotic administration (Pearson’s coefficient = 0.260, p = 0.039). Patients who underwent surgery on the day of admission had 25% shorter hospital stay than patients who had delayed surgery (p < 0.01). Our calculated sensitivity-optimized SPOA volume cutoff of 0.231 mL yielded sensitivity of 90.9% and specificity of 70.0%.

Conclusions

This is the first study to use lesion-mapping software for precise calculation of SPOA volumes, which can help refine indications for early surgical intervention and help decrease length of hospital stay.

Clinical Characteristics and Prognosis of Adult Orbital Cellulitis in a Tertiary General Hospital

Purpose

Adult orbital cellulitis (OC) occurs relatively rarely, and comprehensive studies that retrospectively evaluate OC are lacking. Here, we aimed to examine the clinical characteristics and prognosis of OC in a tertiary general hospital.

Methods

Between October 2010 and May 2019, patients presenting with clinical symptoms of OC in a tertiary general hospital were analyzed in this retrospective study. Twenty-six cases were identified for a detailed review. In these cases, 16 males and 10 females were diagnosed with orbital cellulitis by clinical characteristics and multimodal examinations. We divided patients into three groups: (1) patients secondary to rhinosinusitis, (2) patients secondary to endogenous infection(s) without endophthalmitis, and (3) patients secondary to endophthalmitis. For each group, age, gender, eye type, combined systemic diseases, clinical presentation, leukocyte count, blood culture, diagnostic imaging, therapeutic methods, length of stay, time of postoperation, and patient prognosis were analyzed in detail.

Results

There were no significant differences regarding age, gender, preoperative leukocyte count, exophthalmia, blood culture, treatment, or visual changes within the three groups (P < 0.05). There were significant differences, however, in postoperative leukocyte count and ophthalmoplegia between the three groups (P < 0.05). The preoperative and postoperative logarithms of the minimum resolution angle scored by the best-corrected visual acuity (LogMAR BCVA) of group 3 were statistically significant compared to group 1 and group 2 (P < 0.05).

Conclusion

We confirmed that the prognosis of OC patients combined with systemic diseases was poor. Patients with OC secondary to endophthalmitis infrequently experience ophthalmoplegia; however, these patients still have poor visual outcomes. Patients cultured positive for Klebsiella pneumoniae infection may not be associated with liver abscess. The level of leukocytes may indicate the condition of the disease.