Rare Presentation of Nasal Mucormycosis

Abstract

Nasal mucormycosis is a rare opportunistic infection of the nasal cavity and paranasal sinuses caused by saprophytic fungi which can rapidly lead to death. It usually affects individuals with poorly controlled diabetes mellitus (especially those with ketoacidosis), solid malignancies, iron overload, extensive burns, in patients undergoing treatment with glucocorticosteroid agents and in patients with neutropenia related to haematologic malignancies. Presentation of nasal mucormycosis is always very extensive, but in some patients, it can present in chronic indolent form also. Here, we present a case of 65-year old male with a history of exposed nasal bone after nasal trauma 8 months back. His diabetes was in control with oral hypoglycaemics. Debridement and local flap closure was done. Culture showed the growth of Lichtheimia corymbifera and in HPE, the fungus was seen branching at right angles. So, we conclude that the possibility of nasal mucormycosis should always be borne in mind so that early and effective treatment can be initiated on time to decrease the morbidity and mortality.

Introduction

Nasal mucormycosis is a rare opportunistic infection of the nasal cavity and paranasal sinuses caused by saprophytic fungi which can rapidly lead to death. It usually affects individuals with poorly controlled diabetes mellitus (especially those with ketoacidosis), solid malignancies, iron overload, extensive burns, in patients undergoing treatment with glucocorticosteroid agents and in patients with neutropenia related to haematologic malignancies.

Case Report

A 65-year old male patient presented to Otorhinolaryngology outpatient department with the complaint of exposed nasal bone for the past 8 months. He was a diabetic patient who had a history of trauma on nose one year back which caused a non-healing wound on the nose with exposed nasal bone (Fig. 1). His blood sugar levels were controlled on oral hypoglycaemics, metformin and glimipride. Glycosylated haemoglobin was 4.5%.

Fig. 1.

Pre operative

The patient was operated under general anaesthesia and nasal bone debridement with local flap closure was done. The necrotic bone consisted of bilateral nasal bones with perpendicular plate of ethmoid with medial part of bilateral frontal processes of maxilla. There was no evidence of fungal infection anywhere else in the body. The biopsy report of nasal bones confirmed fungal infection and culture confirmed growth of Lichtheimia corymbifera. Histopathological examination revealed presence of broad non-septate fungal hyphae with irregular branching at right angles.

The patient was given oral itraconazole 200 mg twice a day for 3 months. The wound healed and patient is free of symptoms at 6 months of follow up (Fig. 2). Approval was taken from the Departmental Board of Postgraduate Studies which is equivalent to IRB.

Fig. 2.

Post operative

Discussion

Mucormycosis is an opportunistic infection caused by ubiquitous molds of the order Mucorales. Important immunosuppressive conditions associated with mucormycosis include diabetes mellitus, hematological malignancies, use of corticosteroids and other immunosuppressive agents in transplant recipients and severe burn patients [1].

The common clinical manifestations of mucormycosis are rhinocerebral, pulmonary, gastrointestinal and cutaneous, depending on the routes of infection. The most common species of Mucorales associated with mucormycosis belong to the genera Rhizopus, Rhizomucor, Mucor and Absidia, which all belong to the family Mucoraceae [2]. Among the Absidia species, the most important species associated with mucormycosis is A. corymbifera. Most of these were cases of mucormycosis in traumatic wounds secondary to injuries following initial soil contamination [3].

Infection with Zygomycetes can be acquired by inhalation, ingestion or the deposition of spores in wounds. The fungi give rise to pathogenic lesions as a result of invasion and growth within the lumen and walls of major blood vessels, with ensuing thromboembolism resulting in ischaemia and tissue necrosis. Upon germination, the fungus may spread inferiorly to invade the palate, posteriorly to invade the sphenoid sinus and beyond into the cavernous sinus, laterally to involve the orbits, or cranially to invade the brain. The fungus has a propensity to grow along the elastic lamina of the blood vessels, dissecting the lamina away from the media. This direct invasion and dissection by the fungus causes extensive endothelial damage, resulting in thrombus formation and ischaemia to the surrounding tissues. The infarcted tissue creates an environment that promotes fungal proliferation and the resultant poor vascular supply prevents systemic medical therapy from eradicating the fungus. The nasal and sinus walls are invaded via these vessels and the orbit is invaded secondarily via freely communicating foramen and venous channels. The fungus invades the cranium through either the orbital apex or the cribriform plate of the ethmoids and ultimately kills its host. Four factors are critical for eradicating mucormycosis: rapidity of diagnosis, reversal of the underlying predisposing factors (if possible), appropriate surgical debridement of infected tissue and appropriate antifungal therapy.

In the literature, surgical debridement of the wound followed by amphotericin B and itraconazole is recommended treatment [4,5].

Conclusion

Management of patients suffering from mucormycosis should be multidisciplinary and initiated without delay. High-dose Ambisome® (3 to 5 mg/kg) should be prescribed for 1 month, with early surgery and subsequent replacement by posaconazole (800 mg/day) or itraconazole (200 mg twice a day). Hence, the possibility of mucormycosis should always be borne in mind while dealing with chronic indolent cases also.

Funding

None.

Compliance with Ethical Standards

Conflict of interest

The authors declare that there is no conflict of interest.

Ethical Approval

It was taken from Departmental Board of Postgraduate Studies which is equivalent to IRB.