Rhino-Orbitocerebral Mucormycosis Caused by Apophysomyces elegans

Abstract

Rhino-orbitocerebral mucormycosis (ROCM) caused by more common zygomycetes (e.g., Mucor) is known to cause rapidly fatal infections in immunocompromised patients. Apophysomyces elegans is an emerging zygomycete that has been reported to cause invasive cutaneous and rhino-orbitocerebral infections in immunocompetent individuals. Limited data exist describing the syndrome of ROCM caused by A. elegans. We describe a recent case and performed a comprehensive literature review to delineate the clinical characteristics of ROCM caused by A. elegans. Our case is a 50-year-old man with diabetes mellitus who presented with facial pain and right eye proptosis. Endoscopic sinus sampling revealed A. elegans. He was treated with liposomal amphotericin B and multiple debridements, with no disease on 1.5-year follow-up examination. Seven cases were identified on literature review, including the present case. Most patients (86%) were male, with a mean age of 40 years. Most patients (71%) did not have predisposing medical conditions. Three patients had predisposing head trauma. All presented with facial and/or periorbital pain. All had magnetic resonance imaging or computed tomography of the head showing intraorbital and/or sinus inflammation. Diagnosis was confirmed by histopathology and deep tissue culture in all cases. All patients required eye exenteration and extensive surgical debridement, in addition to intravenous amphotericin B. Six of the seven patients (86%) recovered. ROCM caused by A. elegans is rarely reported in the literature. Most such infections occurred in immunocompetent patients, often after facial trauma. Survival in ROCM caused by A. elegans is favorable in reported cases, with prompt surgical debridement and antifungal therapy. Mucormycosis is a rare necrotizing infection caused by fungi within the class Zygomycetes and the order Mucorales (7). These fungi can cause serious and rapidly fatal infections, particularly in the immunocompromised, such as poorly controlled diabetics with ketoacidosis (17). The genera reported to cause invasive infection include Absidia, Mucor, Rhizomucor, Rhizopus, Apophysomyces, Saksenaea, Cunninghamella, Cokeromyces, and Syncephalastrum, with the first four being the most commonly reported pathogens (7). Apophysomyces elegans is an emerging pathogen that, unlike the other members of Mucorales, has been reported to cause invasive cutaneous and rhino-orbitocerebral infections in immunocompetent individuals (37). In rhino-orbitocerebral infections, inhalation is the natural route of infection. However, traumatic inoculation has been described, particularly with Apophysomyces elegans (17).In 2001, Garcia-Covarrubias et al. reported a review of the literature of mucormycosis attributable to Apophysomyces elegans (17). At that time, there were 21 reported cases of mucormycosis caused by A. elegans since 1985, only 4 of which were rhino-orbitocerebral mucormycosis (ROCM) (2-4, 8-10, 13, 17, 19-22, 24-28, 31, 36-37). Since then, there have been 13 more reported cases of Apophysomyces ...

“Apophysomyces elegans causing Rhino-Orbital Mucormycosis.”

“…1 Two case reports of rhino-orbito-cerebral mucormycosis caused by Apophysomyces elegans have also been reported by Chakrabarti A et al (2003) from India. 3 Our case is similar to the case report described by Liang et al (2006) including the symptoms, signs, treatment and outcome. Apophysomyces elegans shows good response to treatment with amphotericin B.…”

“…The genera reported to cause invasive infection include Absidia, Mucor, Rhizomucor, Rhizopus, Apophysomyces, Saksenaea, Cunninghamella, Cokeromyces, and Syncephalastrum, with the first four being the most commonly reported. 1 These fungi can produce serious and rapidly fatal infections, especially in the immunocompromised patient. Apophysomyces elegans has been reported as an emerging pathogen that can cause primary cutaneous zygomycosis in healthy patients.…”

Apophysomyces elegans Caused Rhino-Orbito Mucormycosis: An Emerging Infection in Immunocompetent Individuals: Case Series with Review of the Literature

“…Two similar cases of ROCM reported earlier as otherwise healthy individuals had predisposing systemic conditions and were omitted from our review [14,15].…”

“…Commonly observed presenting signs and symptoms of A. elegans caused ROCM which include fever, headache, orbital pain, proptosis, orbital cellulitis, ophthalmoplegia, progressive loss of vision, sinusitis, nasal congestion, mucosal ulceration and necrosis, and central retinal artery occlusion, are similar to the classical features of ROCM caused by other mucorales [4][5][6][7][8][9][10][11][12][13][14][15][16]. Skin or mucosal necrosis, and necrotic echar in nasal cavity, though reported in A. elegans caused ROCM in diabetic patients, are unlikely in immunocompetent / otherwise healthy individuals [10].…”

Evidence Implicating Thamnostylum lucknowense as an Etiological Agent of Rhino-Orbital Mucormycosis

“…Note that our data strongly suggest but do not confirm that T. lucknowense caused the infection, because no cultures were made using tissue samples from deep within the patient and an autopsy was not performed. As is common with rhino-orbital infections (9,12,13,17), our patient had the predisposing condition of uncontrolled diabetes mellitus. She presented with symptoms consistent with rhino-orbital mucormycosis, including fever, nasal obstruction, orbital proptosis with swelling and painful erythema, and loss of vision.…”