An Emergent Entity: Indolent Mucormycosis of the Paranasal Sinuses. A Multicenter Study

Abstract

Introduction Indolent or chronic mucormycosis is a rare entity that affects both immunosuppressed and immunocompetent individuals. Additionally, its clinical evolution is nonspecific and there is no standardized treatment for this condition. Objective To describe the clinical characteristics and management of patients with indolent mucormycosis. Methods In the project of study with chart review in the Interinstitutional secondary care centers, patients with evidence of indolent mucormycosis, defined as pathological confirmation of nasal/paranasal sinus mucormycosis for more than 1 month, were included. All patients underwent complete laboratory workup, imaging studies, surgical treatment and adequate follow-up. No evidence of disease status was defined when patient had subsequent biopsies with no evidence of mucormycosis. Results We included seven patients, three female and four male subjects. The mean age was 53.14 years. Four patients were immunosuppressed and three immunocompetent. Among the immunosuppressed patients three had diabetes and one had dermatomyositis. The symptoms were nonspecific: facial pain/headache, mucoid discharge and cacosmia were the ones most frequently reported. Maxillary sinus involvement was present in all patients. Two immunosuppressed subjects received amphotericin. Posaconazole was the only treatment in one immunosuppressed patient. All immunocompetent patients had single paranasal sinus disease and received only surgical treatment. All patients are alive and free of disease. Conclusion Indolent mucormycosis is a new and emerging clinical entity in immunosuppressed and immunocompetent patients. Single paranasal sinus disease is a frequent presentation and should not be overlooked as a differential diagnosis in these patients. Immunocompetent patients should only be treated surgically.

Keywords: chronic mucormycosis; mucorales; mucormycosis; mycoses; paranasal sinuses; sinusitis.

Fig. 1

Case 1. Chronic orbital mucormycosis. (A-D) Computed tomography scan shows intraorbital density, predominantly on the apex region. (E). Periodic acid-Schiff (PAS) stain showing mucormycosis with 90-degrees non-septated hyphae.

Fig. 2

Case 2. (A and B) Computed tomography scan shows left maxillary sinus with heterogeneous density and osteitis. (C) Hematoxylin eosin stain (100x) and (D) Periodic acid-Schaff stain (400x) demonstrate respiratory epithelium with thick hyphae; at higher magnification, non-septated hyphae with right angles are confirmed (red arrow).

Fig. 3

Case 3. Pathology specimen shows edematous mucosa with lymphocyte and plasmatic cells infiltration. Abundant irregular hyphae were observed, with 15 to 30µm, broad with thin wall, non septated, with irregular ramifications filling blood vessels.

Fig. 4

Case 4. Computed tomography scan showing osteitis of maxillary walls and occupation with heterogeneous density of left maxillary sinus.

Fig. 5

Case 5. (A) Computed tomography scan demonstrates left maxillary sinus occupation. (B) Periodic acid-Schaff stain (100x): necrotic tissue with mixed inflammatory cells and hyphae with diverse diameters non septated, with some showing 90-degrees angulation, compatible with mucor (red arrow). (C, D, E, F) Grocott Gomori stain (40x, 100x, 400x): abundant non-septated hyphae with 90-degree angulation; this stain was highly positive on hyphae walls.

Fig. 6

Case 6. (A) Computed tomography scan with total right maxillary sinus heterogeneous occupation. (B) Periodic acid-Schiff stain (400x) shows numerous thick hyphae semi-septated (yellow arrow) with 90-degrees angulation (red arrow) (C) Hematoxylin eosin stain (100x) shows abundant pauci-septated hyphae with right angles and necrosis. (D) Grocott Gomori stain (100X) shows abundant hyphae compatible with zygomycetes.

Fig. 7

Case 7. (A) Computed tomography scan with left total maxillary sinus occupation. (B) Periodic acid-Schiff (PAS) stain (400x) showing spores and scant hyphae compatible with mucormycosis. (C) Hematoxylin eosin stain (400 x) showing inflammatory cells, spores and hyphae compatible with mucor. Figure D and E show non-septated hyphae on PAS stain (100x).