A case of malignant otitis externa caused by Candida glabrata in a patient receiving haemodialysis

Trends and Outcomes of Fungal Temporal Bone Osteomyelitis: A Scoping Review

INTRODUCTION

Temporal bone osteomyelitis is an invasive infection most often caused by bacteria and associated with high mortality. Fungal etiologies are rare and little is known of the predictors of disease severity and outcomes in fungal temporal bone osteomyelitis.

MATERIALS AND METHODS

A scoping review was performed to determine what is known from the literature on how clinical, diagnostic, and treatment characteristics relate to patient outcomes in fungal temporal bone osteomyelitis. Using PRISMA guidelines, three databases were searched to identify all published cases of fungal temporal bone osteomyelitis. Data were extracted from each study, including clinical, diagnostic, and treatment characteristics, and outcomes.

RESULTS

Sixty-eight studies comprising 74 individual cases of fungal temporal bone osteomyelitis were included. All studies were case reports. There were high rates of diabetes, facial nerve palsy, infectious complications, and need for surgical intervention, as well as a significant delay in the evaluation and diagnosis of fungal temporal bone osteomyelitis. Disease recovery was greater in patients presenting with otorrhea, comorbid diabetes, and in those without facial nerve palsy.

DISCUSSION

Many of the defining characteristics of fungal temporal bone osteomyelitis remain unknown, and future reports should focus on determining factors that improve timely diagnosis and treatment of fungal TBO in addition to identifying prognostic indicators for outcomes and survival.

Beware of covert enemies: Candida orthopsilosis malignant otitis externa with base of the skull osteomyelitis, a case report and review of literature

Background

Malignant otitis externa (MOE) is a serious infection of the external auditory canal that is frequently associated with skull base osteomyelitis (SBO) as well as secondary neurological sequelae. Patients with poorly controlled diabetes mellitus or immunosuppression are at increased risk of developing such critical infection for multiple local and systemic factors. While most cases are secondary to bacterial infections particularlyPseudomonas aeruginosa, fungal infections are also occasionally encountered, often associated with delayed diagnosis and high morbidity and mortality.

Case report

We report a case of a 63 years old man with uncontrolled diabetes mellitus who presented with symptoms and signs of MOE, supported by radiological assessments. The patient was treated presumptively with a prolonged course of antibiotics without clinical improvement, coupled with progression of radiological findings and significant disease extension. Reassessment with biopsies and tissue cultures from external auditory meatus, tempo-mandibular bone, as well as base of the skull grew Candida orthopsilosis. The patient received induction treatment with high dose liposomal amphotericin followed by fluconazole to control disease progression and complications.

Conclusion

Candida MOE with secondary skull base osteomyelitis is rare and difficult to diagnose with no clear guidance on assessment and management. Clinicians should be aware of the unusual presentations where microbiological and histopathological evaluations are essential for proper management.

Fungal Malignant Otitis Externa Involves a Cascade of Complications Culminating in Pseudoaneurysm of Internal Maxillary Artery: A Case Report

Patient: Male, 66

Final Diagnosis: Pseudoaneurysm of internal maxillary artery secondary to fungal malignant otitis externa

Symptoms: Epistaxis

Medication: —

Clinical Procedure: Functional endoscopic sinus surgery, endovascular embolization

Specialty: Infectious Diseases

Candida glabrata Has No Enhancing Role in the Pathogenesis of Candida-Associated Denture Stomatitis in a Rat Model

Many denture wearers suffer from Candida-associated denture stomatitis (DS), a fungal infection of the hard palate in contact with dentures. Biofilm formation by Candida albicans on denture/palate surfaces is considered a central process in the infection onset. Although Candida glabrata is frequently coisolated with C. albicans, its role in DS pathogenesis is unknown. We show here, using a contemporary rat model that employed a patented intraoral denture system, that C. glabrata established stable colonization on the denture/palate. However, in contrast to C. albicans inoculated rats, rats inoculated with C. glabrata exhibited minimal changes in weight gain or palatal tissue damage. Likewise, coinoculation with the two Candida species resulted in no exacerbation of C. albicans-induced DS pathology. Together, our findings indicate that C. glabrata has no inducing/enhancing role in DS pathogenesis.

Denture stomatitis (DS) is a condition characterized by inflammation of the oral mucosa in direct contact with dentures and affects a significant number of otherwise healthy denture wearers. Candida-associated DS is predominantly caused by Candida albicans, a dimorphic fungus that readily colonizes and forms biofilms on denture materials. Previous studies showed a requirement for Candida biofilm formation on both palate and dentures in infection and identified fungal morphogenic transcription factors, Efg1 and Bcr1, as key players in DS pathogenesis. While both C. albicans and Candida glabrata are frequently coisolated in mucosal candidiasis, a pathogenic role for C. glabrata in DS remains unknown. Using an established rat model of DS, we sought to determine whether C. glabrata alone or coinoculation with C. albicans establishes colonization and causes palatal tissue damage and inflammation. Rats fitted with custom dentures were inoculated with C. albicans and/or C. glabrata and monitored over a 4-week period for fungal burden (denture/palate), changes in body weight, and tissue damage via lactate dehydrogenase (LDH) release as well as palatal staining by hematoxylin and eosin (H&E) and immunohistochemistry for myeloperoxidase (MPO) as measures of inflammation. C. glabrata colonized the denture/palate similarly to C. albicans. In contrast to C. albicans, colonization by C. glabrata resulted in minimal changes in body weight, palatal LDH release, and MPO expression. Coinoculation with both species had no obvious modulation of C. albicans-mediated pathogenic effects. These data suggest that C. glabrata readily establishes colonization on denture and palate but has no apparent role for inducing/enhancing C. albicans pathogenesis in DS.

IMPORTANCE Many denture wearers suffer from Candida-associated denture stomatitis (DS), a fungal infection of the hard palate in contact with dentures. Biofilm formation by Candida albicans on denture/palate surfaces is considered a central process in the infection onset. Although Candida glabrata is frequently coisolated with C. albicans, its role in DS pathogenesis is unknown. We show here, using a contemporary rat model that employed a patented intraoral denture system, that C. glabrata established stable colonization on the denture/palate. However, in contrast to C. albicans inoculated rats, rats inoculated with C. glabrata exhibited minimal changes in weight gain or palatal tissue damage. Likewise, coinoculation with the two Candida species resulted in no exacerbation of C. albicans-induced DS pathology. Together, our findings indicate that C. glabrata has no inducing/enhancing role in DS pathogenesis.

Diagnosis and treatment of necrotising otitis externa and diabetic foot osteomyelitis - similarities and differences

OBJECTIVE

Necrotising otitis externa is a severe inflammatory process affecting soft tissue and bone, mostly in diabetic patients. Diabetic patients are also at risk of diabetic foot osteomyelitis, another inflammatory condition involving soft tissue and bone. This review aimed to describe the similarities and differences of these entities in an attempt to further advance the management of necrotising otitis externa.

METHOD

A PubMed search was conducted using the key words 'otitis externa', 'necrotising otitis externa', 'malignant otitis externa', 'osteomyelitis' and 'diabetic foot'.Results and conclusionThe similarities regarding patient population and pathophysiology between necrotising otitis externa and diabetic foot osteomyelitis raise basic questions concerning the effects of long-standing diabetes on the external ear. The concordance between local swabs and bone cultures in diabetic foot osteomyelitis is less than 50 per cent. If this holds true also to necrotising otitis externa, the role of deep tissue cultures should be strongly considered. Similar to diabetic foot osteomyelitis, magnetic resonance imaging should be considered in selected necrotising otitis externa subgroups.

Management of malignant (necrotising) otitis externa

Although malignant (necrotising) otitis externa is not a common diagnosis, there have been a number of recently reported cases with pathogens other than Pseudomonas aeruginosa as the causative organism. In addition, there are many published reports of resistance to antibiotics in cases of malignant otitis externa caused by Pseudomonas aeruginosa. This review aims to assess the cases reported and to clarify the current opinion on the diagnostic criteria and management of such cases.

Prognostic scoring in necrotising otitis externa

Objective:

To collect and analyse data from the published literature concerning the rare condition necrotising otitis externa, in order to formulate a prognostic scoring model based on signs and symptoms.

Design:

Retrospective data collection from published literature, and binary logistic regression analysis of the effect on outcome of identified signs and symptoms.

Results:

Six factors were identified as prognostic of a poorer outcome, including facial nerve involvement, additional cranial nerve involvement, non-cranial nerve neurological involvement, extensive granulations (or oedema) in the external auditory canal, bilateral symptoms and aspergillus species as the causative organism. A four-point scoring model based on these findings is presented.

Conclusions:

A novel, systematic method of data analysis was utilised to construct a prognostic scoring model for necrotising otitis externa. This will better equip clinicians to treat this potentially fatal condition.