April 18, 2024
A 35-year-old, type 2 diabetic woman presents with subacute onset swelling within right nasofacial groove, pain, and fever.
Rhino-Orbito-Cerebral Mucormycosis (ROCM)
- Background:
- Rhino-orbito-cerebral mucormycosis (ROCM) is a rare and potentially life-threatening fungal infection that affects the paranasal sinuses, orbits, and brain caused by a group of fungi called Mucorales, which can gain access to the body through inhalation, ingestion, or direct skin contact with contaminated material.
- Risk factors include individuals with weakened immune systems, diabetic ketoacidosis, and iron overload disorders. Once the fungal spores enter the body, they can invade the blood vessels, leading to tissue necrosis and the characteristic symptoms of ROCM.
- Clinical Presentation:
- ROCM can present with features of sinusitis, facial pain, progressive facial swelling and cellulitis, ocular manifestations, proptosis, chemosis, diplopia, ptosis, and restricted eye movements, black eschar formation, and neurologic complications. In advanced cases, the infection can extend intracranially, leading to headache, seizures, altered mental status, cranial nerve palsies, and coma.
- Key Diagnostic Features:
- Clinical suspicion based on the typical presentation of ROCM is required for the initiation of suitable diagnostic tests. It infiltrates nasal mucosa, causing nonenhancing tissue infarction with potential restricted diffusion.
- Black turbinate sign is present: nonenhancing infarcted nasal turbinates (noninfarcted inflammatory mucosa shows enhancement).
- Soft tissue thickening, sinus opacification, bone erosion, and orbital or cerebral involvement may be seen.
- Always assess critical anatomic structures such as periantral fat, orbit, pterygopalatine fossa, nasolacrimal duct, lacrimal sac invasion, and nasal septal ulceration, and assess for bone integrity.
- The detection of fungal hyphae in tissue samples collected from affected areas is the major diagnostic hallmark of ROCM.
- In severe involvement: cavernous sinus thrombosis, cerebral abscesses, meningitis, and vascular blockages leading to ischemic stroke and tissue necrosis.
- Differential Diagnosis:
- Bacterial sinusitis: Less extensive involvement without associated tissue invasion or necrosis in bacterial sinusitis.
- Malignant tumor: More heterogeneous irregular enhancement with significant bony destruction with discrete mass of variable shape and size seen in malignant tumor compared with invasive mucormycosis. Histopathology with clinical correlation is also needed to reach definitive diagnosis.
- Treatment:
- ROCM requires a multidisciplinary approach involving antifungal therapy, surgical intervention, and management of underlying predisposing factors to control the fungal infection, remove necrotic tissue, restore tissue function, and address any contributing factors. Our patient received 6 weeks of Liposomal IV amphotericin and extensive debridement of involved sinuses and wall of nasal cavity with exenteration of the right orbit. Follow-up evaluation showed good outcome without residual findings.
