Mucormycosis of the Central Nervous System

Abstract

Mucormycosis involves the central nervous system by direct extension from infected paranasal sinuses or hematogenous dissemination from the lungs. Incidence rates of this rare disease seem to be rising, with a shift from the rhino-orbital-cerebral syndrome typical of patients with diabetes mellitus and ketoacidosis, to disseminated disease in patients with hematological malignancies. We present our current understanding of the pathobiology, clinical features, and diagnostic and treatment strategies of cerebral mucormycosis. Despite advances in imaging and the availability of novel drugs, cerebral mucormycosis continues to be associated with high rates of death and disability. Emerging molecular diagnostics, advances in experimental systems and the establishment of large patient registries are key components of ongoing efforts to provide a timely diagnosis and effective treatment to patients with cerebral mucormycosis.

Molecular Diagnostics of Mucormycosis in Hematological Patients: A Literature Review

“…This indicates the representativeness of the examined patients: lungs are the main localization of mucormycosis in hematological patients, rhinocerebral form and disseminated process are common [6,21]. According to a recent review, in allo-HSCT recipients CNS mucormycosis was diagnosed in 11% of all cases, in patients with malignancies-in 4-19% [22].…”

A closer look at pathogenesis of cerebral mucormycosis in diabetic condition: A mini review

“…The CM begins with the inhalation of sporangiospores, asexual spores, which is the best form of penetrating the respiratory tract and colonizing nasal mucosa. Then, it develops in paranasal sinuses, especially ethmoid and maxillary sinuses; rapidly spreads into orbit, cavernous sinuses, and sphenoid sinuses; and finally reaches intracranial fossa [3,10,11]. An important site of infection is ethmoid sinus, which may facilitate the spread of infection through the lamina papyracea into the orbit, extraocular muscles, eye, and optic nerve.…”

“…The diplopia or blindness could be the first clinical sign, and eye fundus is important for the examination as well, which could reveal thrombosis in artery or central vein of the retina, venous congestion, optic atrophy, or panophthalmia [12,14,15]. Furthermore, penetration into the central nervous system (CNS) occurs through either circulation or diffusion directly from paranasal to cranial sinuses [3]. CM occurs as a complication of sino‐orbital mucormycosis, and brain invasion may be mediated by ethmoidal and orbital veins that facilitate the involvement of cavernous sinuses [13].…”

“…Mucormycosis is an uncommon and life‐threatening fungal infection caused by fungi of the order Mucorales, and it is the second most common invasive mold infection after aspergillosis [1–3]. Mucorales usually infect patients with uncontrolled diabetes mellitus and immunosuppressed patients like those affected with hematological cancer or recipients of solid organ [3,4]. Incidence of mucormycosis has increased over the last two decades and the mortality rate is high despite antifungal therapy and surgical operation [5,6].…”

“…In developed countries, malignancy has been recognized as the main risk factor for mucormycosis, whereas in developing nations, uncontrolled diabetes mellitus is still the main factor related to the development of this disease. Furthermore, in developing countries, mucormycosis is frequently reported as a presenting event of diabetes mellitus [3,9]. So, the current mini review was performed to investigate the pathogenesis of CM, especially its corresponding molecular interactions in the body of the patients with diabetes, making them more susceptible to this infection.…”