Enterococcus faecalis ca agent patogen rar în sinuzita acută: prezentare de caz clinic și management chirurgical

1. Introduction and background

Acute bacterial rhinosinusitis is most commonly caused by Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis, in both pediatric and adult populations, especially in uncomplicated, community-acquired infections^(1,2). While these pathogens account for the majority of cases, other aerobic Gram-negative organisms may emerge in selected clinical contexts, mostly including nosocomial infections, immunocompromised states, or chronic sinonasal disease.

Enterococcus faecalis is a Gram-positive, facultatively anaerobic coccus, more frequently associated with uri­na­ry tract infections, endocarditis, or intraabdominal infections. Its implication in upper respiratory tract infections remains exceedingly rare, and is typically reported in patients with prolonged hospitalization, recent surgeries or instrumentation, immunosuppression or exposure to broad-spectrum antibiotics^(3,4). In the context of acute or exacerbated chronic rhinosinusitis in young adults with no predisposing factors, Enterococcus species are seldom isolated.

The available literature suggests that the detection of Enterococcus faecalis in paranasal sinus infections may reflect either contamination, biofilm-driven colonization, or the presence of unrecognized host or environmental risk factors. These include poor hygiene, previous dental manipulation, or community-acquired antimicrobial resistance patterns^(5,6). While rare, such isolates must be taken seriously, due to their increasing multidrug resistance and potential for aggressive local tissue invasion.

This case report describes a 27-year-old male patient with acute exacerbation of chronic rhinosinusitis complicated by palpebral cellulitis and acute sinus infection, in whom Enterococcus faecalis was identified as the primary pathogen. The patient’s lack of prior immunodeficiency, hospitalization, or other conventional risk factors highlights the unusual nature of the infection and underlines the evolving microbiological profile of sinusitis in the post-antibiotic era.

2. Case presentation

We present the case of a 27-year-old male with a long-standing history of untreated chronic rhinosinusitis, who presented at the Emergency Department of the County Emergency Clinical Hospital Craiova, Romania, in January 2024, with a severe exacerbation of symptoms related to an acute sinus infection. He reported a gradual worsening of right-sided facial pain, headache and upper eyelid swelling over the past 10 days, which had acutely deteriorated in the previous 48 hours. The patient had self-administered over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) and nasal decongestants without medical supervision, but noted no significant relief. Upon presentation, he exhibited intense right hemifacial pain, purulent nasal discharge, and marked swelling and erythema of the right upper eyelid, raising concerns for complicated rhinosinusitis with orbital involvement.

On clinical examination, the patient presented low-grade fever, but showed signs of systemic inflammation, with significant right periorbital edema, tenderness over the maxillary and ethmoid regions, and purulent nasal discharge emanating from the right nasal cavity. The upper eyelid was tense, erythematous and partially ulcerated, with crust formation suggestive of a suppurative process involving pre-septal and possible post-septal orbital tissue. Nasal endoscopy confirmed the severe edema and the complete obstruction of the right nostril, the middle nasal meatus being partially visualized. Thick, foul-smelling discharge was present. Laboratory tests revealed elevated leukocyte count (17,400/mm³) and associated neutrophilia, a C-reactive protein level of 138 mg/L, and an erythrocyte sedimentation rate of 68 mm/h, all consistent with acute bacterial infections. Given the alarming local signs and unclear extension of the process, an urgent cranial computed tomography (CT) scan was performed to assess the paranasal sinuses and orbit. The imaging demonstrated complete opacification of the right maxillary sinus, anterior ethmoid sinus and osteomeatal complex, and also complete opacification of the frontal sinus. The palpebral regions presented fluid build-up, but the orbital muscles and eye were unaffected (Figure 1).

Given the clinical severity and the absence of improvement under self-administered treatment, the patient was admitted in the otorhinolaryngology department of our hospital. A nasal swab was obtained from the right middle meatus prior to initiating any antimicrobial treatment, being sent for microbiological analysis, including aerobic and anaerobic bacterial cultures and antimicrobial susceptibility testing. Empirical intravenous therapy was started with ceftriaxone (2 g/day) as a broad-spectrum beta-lactam antibiotic. Concurrently, intravenous dexamethasone was administered to mitigate inflammation and prevent orbital complications, while topical nasal decongestants and mechanical aspiration of nasal secretions were performed to improve sinus drainage and reduce mucosal edema.

After approximately 24 hours of conservative medical therapy, no significant improvement was noted in patient symptoms. The right upper eyelid remained significantly swollen, tender and partially necrotic at its center, and the patient continued to report intense unilateral headache. Considering orbital and other intracranial complications and despite the patient’s young age, a surgical intervention was deemed necessary. The patient underwent urgent sinus surgery under general anesthesia. The surgical intervention consisted of a limited endoscopic anterior ethmoidectomy and a wide maxillary antrostomy aimed at restoring patency of the right osteomeatal complex and facilitating drainage of the affected sinuses. Simultaneously, an external Ogston-Luc approach via the superior palpebral region was performed to access the frontal sinus, allowing for meticulous debridement and removal of necrotic tissue extending into the upper palpebral region. Intraoperatively, the maxillary and ethmoidal sinuses were found to be extensively filled with dense purulent secretions, while the mucosa appeared markedly inflamed, friable and hypertrophic. The purulent material was thoroughly suctioned, and all involved sinus cavities were copiously irrigated with warmed sterile saline. Hypertrophic and necrotic mucosa was excised and submitted for histopathological analysis, which revealed no evidence of neoplasia or granulomatous disease. To maintain frontal sinus drainage and prevent postoperative obstruction, a stent tube was placed from the frontal sinus through the frontonasal duct and directed inferiorly into the nasal cavity, exiting into the inferior meatus to allow for ongoing aspiration and aeration during the postoperative healing phase (Figure 2).

Postoperatively, intravenous ceftriaxone was continued, and empirical coverage was expanded to include vancomycin (1 g every 12 hours), given the suspicion of a Gram-positive etiology with potential multidrug resistance or Gram-negative cocci. Renal function was monitored closely throughout the antibiotic course, and urea and creatinine levels remained within physiological limits.

On the third day of hospitalization, culture results identified Enterococcus faecalis as the predominant pathogen isolated from the sinus secretions. The strain was sensitive to both ceftriaxone and vancomycin, confirming the appropriateness of the selected antibiotic regimen. Although no vancomycin-resistant Enterococcus (VRE) markers were identified, the presence of a robust local infection and the pathogen’s known capacity for horizontal gene transfer prompted a cautious continuation of targeted therapy under close surveillance.

The patient showed marked clinical improvement within 48 hours of surgery. The remaining periorbital edema began to regress, and the facial pain resolved completely. He was discharged on the 14^th postoperative day with normalized inflammatory markers, and he was instructed to continue saline nasal irrigation and mucolytic therapy at home (Figure 3). Follow-up nasal endoscopy at 30 and 60 days postoperatively demonstrated a well-healed sinonasal cavity with no purulent discharge or residual inflammation. Given the favorable clinical outcome and a clean endoscopic field, no diplopia and normal eye movements, repeating the CT imaging was not deemed necessary. A topical intranasal probiotic formulation containing Streptococcus salivarius was recommended to prevent recolonization or dysbiosis.

3. Discussion

Previously classified within the Lancefield group D streptococci, enterococci have since been redefined as a distinct genus based on DNA homology analyses. Although once regarded as low-virulence commensals with limited clinical relevance, enterococci have emerged as significant nosocomial pathogens⁽⁷⁾.

Enterococci are Gram-positive cocci arranged in pairs or chains, exhibiting facultative anaerobic metabolism. They are part of the normal human gastrointestinal microbiota, where they exist as commensals. However, under certain conditions, they can act as opportunistic pathogens⁽⁸⁾. Clinically, they are most frequently associated with urinary tract infections, intraabdominal infections, bacteremia and infective endocarditis. Less commonly, enterococci may cause central nervous system infections such as meningitis, as well as osteomyelitis, septic arthritis, or pulmonary infections. Enterococcus spp. have emerged as potential etiological agents in both upper and lower respiratory tract infections, including those involving the paranasal sinuses⁽⁹⁾. 

Recent epidemiological surveillance places enterococci as the third most frequently isolated pathogens in hospital settings, accounting for approximately 12% of all nosocomial infections – preceded only by coagulase-negative staphylococci and Staphylococcus aureus⁽¹⁰⁾.

Enterococcus spp. represent a significant cause of nosocomial infections, particularly among immunocompromised individuals. The increasing incidence of vancomycin-resistant Enterococcus (VRE) across Europe is a growing public health concern, especially given the emergence of resistance to last-line antimicrobial agents⁽¹¹⁾. Enterococcus spp. have acquired multiple mechanisms of resistance to a broad spectrum of antimicrobial agents, including aminoglycosides, b-lactams, tetracyclines, quinolones, and glycopeptides such as vancomycin. Intrinsically, they exhibit low-affinity penicillin-binding proteins, possess the ability to produce b-lactamases, and demonstrate reduced cellular permeability to various antibiotic classes, all of which contribute to their resilience in clinical settings⁽¹²⁾. Enterococcal infections have been associated with several independent risk factors, including abdominal surgery, structural abnormalities of the urinary tract, male sex, and hypoalbuminemia; additionally, immunosuppressive therapy and the presence of indwelling medical devices further increase the risk, particularly for Enterococcus faecium infections⁽¹³⁾. Several studies listed before have brought forward a host of resistance genes which, if identified in target bacterial isolate, may complicate the clinical outcomes.

Enterococcus species are part of the normal human microbiota, but they can become opportunistic pathogens in certain conditions. In chronic sinusitis, the microbiological flora is often polymicrobial, with bacteria such as Staphylococcus aureus, Pseudomonas aeruginosa and Haemophilus influenzae being more commonly implicated^(14,15). However, Enterococcus species can also contribute to sinus infections, particularly in cases where there is a disruption of the normal microbiota or in immunocompromised patients.

The presence of Enterococcus in sinus infections may be associated with biofilm formation, which can complicate treatment by reducing the efficacy of antibiotics and host immune responses⁽¹⁶⁾. Additionally, Enterococcus spp. are known for their ability to develop antibiotic resistance, including resistance to beta-lactams and macrolides, which are commonly used in treating sinus infections⁽¹⁷⁾.

Chronic sinusitis affects a wide range of patients, with studies indicating a male predominance in some populations⁽¹⁴⁾. Enterococcus infections, in general, can occur across all age groups, but may be more prevalent in older adults or in those with underlying health conditions. How­ever, specific data on the demographics of Enterococcus sinus infections in chronic sinusitis are limited. Patients with compromised immune systems or underlying conditions such as diabetes, cystic fibrosis or allergic rhinitis are more susceptible to chronic sinusitis and may be at higher risk for Enterococcus infections^(17,18). Additionally, patients with nasal polyps often have higher rates of comorbidities such as asthma, which may further complicate treatment and increase the likelihood of microbial colonization⁽¹⁹⁾.

Although Enterococcus species are not traditionally associated with primary sinonasal infections, emerging reports suggest they may colonize the nasal and paranasal sinuses, particularly in the context of disrupted mucosal integrity or altered local immunity. In immunocompetent individuals without prior hospitalizations or comorbidities, colonization by Enterococcus faecalis may reflect poor hygiene or environmental exposure rather than underlying systemic immunosuppression. The ability of enterococci to form biofilms on mucosal surfaces contributes to their persistence and resistance to conventional antibiotic therapy, particularly in ca­ses where epithelial barriers are compromised. Given the rarity of Enterococcus-related acute rhinosinusitis in other­wise healthy adults, the identification of this path­o­­­gen should prompt clinicians to consider nontradi­tio­nal risk factors – most notably inadequate personal hygiene or exposure to contaminated communal en­viron­­ments – as potential sources of infection^(20-23).

The severity and progression of bacterial sinusitis play a pivotal role in determining the necessity for surgical intervention, especially when medical therapy proves insufficient. Endoscopic sinus surgery is primarily indicated in patients with chronic rhinosinusitis unresponsive to maximum medical therapy or in cases of acute sinusitis with complications such as orbital cellulitis, subperiosteal abscess, or intracranial extension^(24,25). While most cases of acute bacterial sinusitis resolve with antibiotics, surgical intervention becomes essential when there is no clinical improvement, or when imaging confirms complications that threaten ocular or neurological integrity⁽²⁶⁾.

Specific surgical indications include:

• failure of maximal medical management in chronic or recurrent acute rhinosinusitis⁽²⁷⁾;
• complicated acute sinusitis presenting with orbital cellulitis, abscess or cavernous sinus thrombosis⁽²⁴⁾;
• frontal sinus involvement requiring external drainage approaches such as a modified Ogston-Luc procedure in cases where endoscopic access is limited⁽²⁸⁾.

Although Enterococcus faecalis is rarely implicated in sinonasal infections, when isolated in the setting of purulent, necrotic sinusitis – particularly in immunocompetent individuals –, it may reflect a pathogen with biofilm-forming potential and heightened resistance patterns. This microbiological profile, combined with extensive tissue involvement, reinforces the need for early and aggressive surgical debridement to prevent further complications and to achieve source control⁽²⁹⁾.

4. Conclusions

This case highlights an emerging clinical phenomenon in which traditionally nosocomial or opportunistic pathogens such as Enterococcus faecalis can manifest as primary etiological agents in community-acquired sinonasal infections – even in immunocompetent patients without classical risk factors. The identification of Enterococcus faecalis in acute complicated rhinosinusitis, coupled with its known capacity for biofilm formation and multidrug resistance, emphasizes the evolving microbiology of upper respiratory tract infections in the post-antibiotic era. In this case, the lack of systemic immunosuppression, prior hospitalization, or recent antibiotic exposure points toward alternative acquisition routes such as poor hygiene or community-level transmission, aligning with similar observations in contemporary microbiome studies^(30,31).

Early imaging, microbiological sampling and decisive surgical intervention were central to the very good outcome in this patient. The dual approach of endoscopic sinus surgery and external drainage via Ogston-Luc approach ensured the complete evacuation of purulent material and prevention of orbital complications. In such cases, culture-directed therapy – particularly when rare pathogens like Enterococcus faecalis are identified – remains critical for achieving resolution. The presence of resistant virulence genes further highlights the importance of considering prompt surgical debridement not only for main disease control, but also for minimizing the potential dissemination of resistant strains⁽³²⁾. Future reports and surveillance are essential to determine whether such pathogens represent isolated events or an under-recognized trend in community-acquired sinonasal infections.

Institutional review board statement: The study was conducted in accordance with the Declaration of Helsinki.

Informed consent statement: Informed consent was obtained from all subjects involved in the study.

Autor corespondent: Alexandra Bucătaru E-mail: alexandra.catana95@gmail.com; Andrei Osman E-mail: andrei.osman@umfcv.ro

CONFLICT OF INTEREST: none declared.

FINANCIAL SUPPORT: none declared.

This work is permanently accessible online free of charge and published under the CC-BY.