Preseptal and Orbital Cellulitis in Children

Unilateral eyelid inflammation is a common reason for pediatric consultations. When caused by infection, it is crucial to distinguish between preseptal (or periorbital) cellulitis and orbital cellulitis. The 2 entities can have a very similar presentation, and their clinical distinction can be challenging. However, differentiating between them promptly is essential due to significant differences in their management and prognostic implications.1–3 Epidemiology Both orbital and preseptal cellulitis are more common in children than in adults. Among children, preseptal cellulitis occurs far more frequently than orbital cellulitis. Preseptal cellulitis is mostly seen in children under 5 years of age. Orbital cellulitis, on the other hand, is more prevalent in older children, with a mean age of 7 years, although cases have been reported from less than a month of life up to 18 years.1,2,4 Anatomical Focus Understanding orbital anatomy is key to grasping the pathogenesis, clinical presentation, and complications of preseptal and orbital cellulitis. The orbital septum, a connective tissue barrier, delineates the 2: preseptal cellulitis involves the eyelid anterior to the septum, while orbital cellulitis affects orbital contents (fat and muscles) posterior to the septum. Neither condition involves the globe itself.1,5 The orbit is a conical structure housing the ocular globe, fat and extraocular muscles, bordered by paranasal sinuses. Its roof lies adjacent to the frontal sinus, the floor contacts the maxillary sinus and the medial wall is separated from the ethmoidal sinus by the thin lamina papyracea, which allows passage of vessels and nerves. Venous drainage from the orbit and surrounding structures converges in the cavernous sinus, facilitating infection spread. In children, thinner sinus walls and greater bone porosity further elevate this risk. Etiopathogenesis The primary routes of transmission and pathogenic agents are summarized below, though orbital cellulitis may rarely occur without predisposing conditions.2,4,6 Skin contiguous spread: more common in preseptal cellulitis, often originating from skin infections of the eyelid due to trauma, insect bites or infected wounds. Other sources include infections of ocular appendages (eg, dacryocystitis, dacryoadenitis and hordeolum).2,4 Skin-origin infections are typically caused by Staphylococcus aureus or group A Streptococcus.2 Sinusitis: the leading cause of orbital cellulitis and a frequent source of preseptal cellulitis, with the ethmoidal sinus being the most commonly involved, followed by the maxillary sinus. Common pathogens include S. aureus, Streptococcus spp. (S. anginosus, S. pyogenes and S. pneumoniae), Haemophilus influenzae (nontypeable), Moraxella catarrhalis and anaerobes (Bacteroides, Prevotella and Fusobacterium). Polymicrobial infections are common.6–10 Hematogenous spread: rare and primarily affecting infants, it involves bacteremia and seeding in the preseptal space. Previously, H. influenzae type B (Hib), together with S. pneumoniae, was a leading cause but has diminished due to vaccination.8–10 Occasional cases may involve S. pyogenes bacteremia.7 Monitoring local resistance patterns is crucial, given the variability in methicillin-resistant Staphylococcus aureus (MRSA) prevalence, although recent data suggest a stable trend rather than an increase.7,11,12 Cases of both preseptal and orbital cellulitis caused by MRSA have been reported with inconsistent findings regarding predisposing factors and clinical severity. While the data in the literature are conflicting—some studies suggest a more severe course, while others do not identify a clear difference—young age, particularly under 1 year, appears to be a potential predisposing factor for MRSA infection, although the underlying reasons remain uncertain.7,11–13 Classification The Chandler classification categorizes the severity of orbital and periorbital infections based on severity, although it does not represent a true continuum of disease5: Group I: preseptal or periorbital cellulitis. Group II: orbital cellulitis. Group III: subperiosteal abscess. Group IV: orbital abscess. Group V: cavernous sinus thrombosis. Clinical Manifestations As previously mentioned, distinguishing between preseptal and orbital cellulitis can be challenging, as both conditions typically present with unilateral eyelid swelling and erythema. However, erythema is not always observed in orbital cellulitis. Fever can occur in both cases, though it is more commonly associated with orbital cellulitis. Importantly, initial orbital cellulitis might present only with eyelid inflammation and eye pain and findings such as limited eye movements, proptosis, decreased visual acuity and diplopia, although specific to orbital cellulitis, typically manifest only in severe and/or complicated cases.2–4,9 Complications Complications are rare in preseptal cellulitis, but may include, for example, eyelid abscesses.4In case of orbital cellulitis, practitioners should have an increased clinical suspicion for intracranial extension in those with headache, vomiting, mental status changes and any focal neurologic findings.1,2,4,9 The main complications associated with orbital cellulitis are1,3,9: Abscess formation: subperiosteal abscesses are the most common, followed by orbital abscesses.9,10 Cavernous sinus thrombosis: suspect with bilateral proptosis or VI/VII cranial nerves involvement. When severe, internal carotid artery thrombosis with cerebral infarct can occur. Visual loss: may result from increased orbital pressure, retinal artery occlusion, optic neuritis or atrophy or exposure keratitis. Intracranial spread: may cause meningitis, subdural or epidural empyema or brain abscesses. Diagnosis A thorough clinical history (eg, trauma, dental procedures and vaccinations) and a comprehensive physical examination, including assessment of intrinsic and extrinsic eye movements, meningeal signs and a neurologic examination, are essential. Preseptal cellulitis is typically diagnosed clinically. If orbital cellulitis is suspected, further evaluation is warranted.2–4,14 Imaging Contrast-enhanced CT of the Orbits and Sinuses Contrast enhanced computed tomography (CT) is most useful and commonly used test in the initial management. Common findings in orbital cellulitis include diffuse involvement of the periorbital fat and extrinsic ocular muscles. CT is also effective for identifying complications, both intraorbital and intracranial, such as abscesses or superior ophthalmic vein thrombophlebitis, which may precede or coexist with cavernous sinus thrombosis. Key indications for a CT scan, as outlined in the literature, include gross proptosis, significant ophthalmoplegia, deteriorating visual acuity, bilateral edema, lack of clinical improvement after 24 hours of intravenous antibiotics, signs or symptoms of central nervous system involvement or inability to adequately assess the ocular globe.14,15 Additionally, a retrospective study of 918 patients identified neutrophilia >10,000/μL and edema extending beyond the eyelid margins as potential predictors of a higher risk for orbital abscess.16 In contrast, children without significant ophthalmoplegia or vision loss, and in whom an eye examination can be reliably performed, may initially be managed without imaging. Brain MRI Brain magnetic resonance imaging allows for better visualization of the orbit and its contents compared to CT scan, and it does not involve irradiation.17,18 However, its use may be limited by the need for sedation, variable availability and higher cost. Nonetheless, it should definitely be considered when intracranial complications are suspected.11,14 Orbital Ultrasound Its accessibility, absence of ionizing radiation exposure and lack of need for general anesthesia render it a promising future diagnostic tool for differentiating orbital inflammation. It may also play a role in serial assessments to monitor response to therapy. However, the quality of the available evidence is poor, being mostly based on case reports and outdated studies, particularly in the pediatric population. Further research is needed to better define the sensitivity, specificity and clinical impact of orbital ultrasound compared to cross-sectional imaging.18 Paranasal Sinus Radiography Paranasal sinus radiography is no longer recommended as it is common in upper respiratory viral infection to show sinus occupation. Blood Tests Blood tests are not routinely indicated for preseptal cellulitis, as the diagnosis is primarily clinical and such tests do not aid in differentiating it from orbital cellulitis. However, patients with orbital cellulitis typically exhibit higher levels of leukocytosis and C-reactive protein compared to those with preseptal cellulitis, although no universally accepted cutoff exists.4,14 A retrospective study from a Spanish tertiary hospital proposed a C-reactive protein cutoff of 117.5 mg/L, with a specificity of 93.4%, for diagnosing orbital cellulitis.3 Microbiology Blood cultures should be obtained in cases of orbital cellulitis, despite their typically low yield.7,8,14 They may also be indicated for patients with presumed preseptal cellulitis, particularly in young infants, severely ill individuals, those who are not immunized or when bacteremic spread is suspected. In cases where an abscess is drained, samples should be sent for Gram stain and culture. Cultures from sinus aspirates or eyelid secretions are often contaminated and rarely influence management decisions.6,7,14 Treatment A multidisciplinary approach is essential for achieving optimal clinical outcomes. Management should initially involve collaborative evaluations by pediatricians and otorhinolaryngologists. Ophthalmologists and neurosurgeons may also need to be consulted if there are signs of ocular or central nervous system involvement that warrant their expertise or intervention. This coordinated approach ensures early diagnosis and timely management, helping to prevent or address potential complications effectively.14,19 Management can be primarily conservative, centered on antibiotic therapy. The role of corticosteroids as an adjunctive treatment remains controversial, as discussed ahead. In some cases, a more invasive approach may be required. However, in recent years, the literature has reported a tendency toward more conservative management strategies.9,10 Antibiotic Therapy Antibiotics should be initiated early and empirically, as microorganism isolation is often unavailable, and no clinical trials currently guide antibiotic selection nor its duration. The choice of antibiotics depends on the suspected pathogen, informed by local epidemiology, clinical history, physical examination, drug availability and the prescribing physician’s expertise or preference. Therefore, the following indications are based on the data available from case series and retrospective data.3,4,6,7,9,20–22 Preferred antibiotic regimens for both preseptal and orbital cellulitis are detailed in Table 1. TABLE 1. - Antibiotic Regimens for Preseptal and Orbital Cellulitis Infection Type Relevant Risk Factors/Clinical Context Antibiotic Treatment Options Preseptal cellulitis Presence of skin trauma:(suspected to be caused by skin flora. Include coverage for Group A Streptococcus and Staphylococcus aureus. Consider covering MRSA depending on epidemiology) Oral antibiotic:-First-generation cephalosporin (eg, cefalexin, cefadroxil)-Alternative: Amoxicillin-clavulanic acidIV antibiotic:-Cefazolin-Alternative: Amoxicillin-clavulanic acid Absence of skin trauma:(Include coverage for Streptococcus pneumoniae, S. aureus. Consider covering MRSA depending on epidemiology) Oral antibiotic:-Amoxicillin-clavulanic acidor-CefuroximeIV antibiotic:-Amoxicillin-clavulanic acid or Cefuroxime Orbital cellulitis Uncomplicated orbital cellulitis:(cover S. aureus, including MRSA, Streptococci spp, and anaerobes) IV antibiotic:Possible regimens:-Third-generation cephalosporin + clindamycinor-Amoxicillin-clavulanate (if intracranial involvement excluded and likely rhinosinusitis focus). Oral antibioticOnly after at least 3–5 days of IV therapy: -Amoxicillin-clavulanic acidor-cefuroxime+/− MRSA coverage depending on local prevalence Complicated orbital cellulitis:Intracranial involvement suspected or confirmed(cover S. aureus, including MRSA, Streptococci spp, gram-negative bacilli +/− anaerobes) IV antibiotic:-Third-generation cephalosporin + MRSA coverage + metronidazole (if Intracranial involvement suspected or confirmed)-Third-generation cephalosporin + clindamycin (if subperiostal abscess or orbital abscess without intracranial involvement) If pathogens are isolated from blood cultures or from samples obtained via invasive procedures, therapy should be adjusted according to the antibiogram. Hospitalization Versus Outpatient Management Hospitalization and treatment with intravenous antibiotics are recommended for all cases of orbital cellulitis, regardless of complications.2–4,7,9 For preseptal cellulitis, hospitalization is indicated in the following situations: Infants under 1 year of age. Severely ill patients. Suspect of hematogenous spread. Lack of improvement or worsening within 24–48 hours of oral antibiotic therapy. Family or social circumstances that make outpatient treatment unsuitable or impractical. In other cases, outpatient management may be attempted initially. While in the case of orbital cellulitis, empirical initial coverage of MRSA is usually preferred, especially in areas of high prevalence of MRSA, in the case of preseptal cellulitis MRSA should be covered if suspected or confirmed. Oral options for MRSA coverage include clindamycin, linezolid and trimethoprim-sulfamethoxazole. Intravenous options include clindamycin, linezolid and vancomycin.7,12 In case of allergy to penicillins, in nonserious cases it is possible to choose among second and third-generation cephalosporins based on local availability (cefuroxime, cefpodoxime and cefdinir); in case of serious life-threatening allergy levofloxacin is a viable option. Response to Therapy Improvement should be seen after 24–48 hours of adequate antibiotic therapy; otherwise, it would be indicated to rule out complications. Antibiotic Duration Preseptal cellulitis: 5–10 days, depending on evolution (clinical signs must be resolved before stopping therapy).4,20,21 Orbital cellulitis: 14–21 days. In case of complications, antibiotic therapy should be prolonged (at least 28 days). In case of uncomplicated orbital cellulitis, with good response to therapy and favorable evolution (afebrile and with substantial improvement of orbital signs), switch to oral antibiotics may be possible, usually after 3–5 days. If, however, complications are present (eg, an abscess), it is reasonable to provide at least 10–14 days of intravenous therapy.4,7,9,20–22 Systemic Corticosteroids as Adjuvant Therapy Corticosteroids may theoretically benefit orbital cellulitis by reducing inflammation and edema, which contribute to elevated orbital pressure, vascular compression and potential optic nerve damage. This reduction in pressure could prevent visual impairment, reduce scarring and mitigate long-term complications. While the evidence remains inconsistent, corticosteroids are commonly used in practice as an adjunct to antibiotics due to their potential to accelerate recovery and improve outcomes. Notably, a small randomized controlled trial by Pushker et al23 demonstrated that corticosteroids hastened the resolution of inflammation, improved ocular motility, and reduced hospital stays in a group of 11 to 59-year-old patients with orbital cellulitis, without increasing adverse effects. Some studies also suggest corticosteroids may shorten hospital stays, though larger studies, such as an analysis of 5645 children, found no consistent benefit and highlighted potential risks, including increased operative interventions and pediatric intensive care unit admissions.24 The limitations of existing data, such as reliance on retrospective designs and administrative databases, highlight the need for further prospective trials to clarify the role of corticosteroids in managing orbital cellulitis.25,26 Complications Treatment There is no need for surgery intervention in preseptal cellulitis in the absence of skin collections. In case of orbital cellulitis, surgery should be considered from the onset in cases where complications are present, especially in those cases with intracranial spread confirmed (including cavernous sinus thrombosis and brain abscesses) or vision threatened.19 Subperiosteal Abscess The most common complication is the formation of a subperiosteal abscess. In many cases, with small medial abscesses, antimicrobial therapy alone is often sufficient. However, the need and timing of drainage remain topics of debate. Independent risk factors for surgical intervention, as reported in the literature,19,27,28 include: Size: “Large” abscesses, with reported cutpoints varying from 0.5 to 3.8 mL. Location: nonmedial abscesses or those near the orbital apex. Age: older children (>9 years). Clinical features: severe proptosis, worsening visual acuity, elevated intraocular pressure, color vision impairment or intracranial involvement. Response to antibiotics: poor response after 24–48 hours of intravenous antibiotics. Both large and nonmedial abscesses often fail medical management due to poor antibiotic penetration into avascular, thick-walled cavities. Most subperiosteal abscesses can be successfully drained via functional endoscopic sinus surgery, avoiding external incisions. Other approaches include orbital or endoscopic transcaruncular drainage. Cavernous Sinus Thrombosis Management typically includes a combination of antibiotics, anticoagulation and surgical intervention. A systematic review has recently shown a reduction of mortality in adults with septic cavernous sinus thrombosis in adults.29 The optimal duration of anticoagulation remains undefined.