Mucormycosis

Reviewed and revised 29 July 2015

OVERVIEW

• Mucormycosis is the unifying term used to describe infections caused by fungi belonging to the order Mucorales (e.g. Rhizopus, Rhizomucor, Mucor, and Absidia).
• Rhinocerebral mucormycosis is severe sinusitis with caused by a non-Aspergillus mold, most commonly Rhizopus arrhizus

CLINICAL FEATURES

Rhinocerebral mucormycosis

• headache
• facial pain
• confusion
• fever
• purulent nasal discharge (black)

Other manifestations:

• pneumonia (associated with prolonged neutropenia): dyspnea, cough, hemoptysis
• cutaneous (black lesions)
• GI
• CNS

Complications

• intraorbital extension
• intracranial extension (e.g. leptomeningeal enhancement, intracranial granulomas, epidural abscess)
• vascular invasion (e.g. cavernous or venous sinus thrombosis, mycotic aneurysm formation, cerebral infarction or haemorrhage, systemic dissemination)

RISK FACTORS

• diabetes mellitus (especially wit ketoacidosis)
• burns
• chronic renal failure
• cirrhosis
• immunosuppression
• iron overload and desferrioxime treatment (iron chelator)

INVESTIGATIONS

• blood cultures
• tissue biopsies

Pulmonary mucormycosis

• CXR and CT Chest – lobar consolidation, isolated masses, nodular disease, cavitation, or wedge-shaped infarcts (angioinvasive disease); reversed halo sign on CT (a focus of ground glass surrounded by a solid ring of consolidation)
• BAL

Rhinocerebral mucormycosis

• CT:
  • mucosal thickening (hypoattenuating; e.g. black turbinate sign)
  • opacification of the sinus (in acute fungal sinusitis, unlike in chronic infection, hyperdense material may not be seen in the sinus cavity)
  • bone destruction
  • stranding of fat on the outside of the sinus
• MRI is the modality of choice for demonstrating soft tissue involvement

MANAGEMENT

General

• resuscitation
• supportive care and monitoring
• treat underlying cause and complications (e.g. DKA, immunosuppression, nutrition, GCSF)

Specific

• surgical debridement
• amphotericin B
• consider hyperbaric oxygen

PROGNOSIS

• depending on comorbidities and underlying immunosuppression, mortality may range from ~ 20-80%

References and Links

Journal articles

• Kontoyiannis DP, Lewis RE. How I treat mucormycosis. Blood. 2011 Aug 4;118(5):1216-24. doi: 10.1182/blood-2011-03-316430. Epub 2011 May 26. Review. PubMed PMID: 21622653; PubMed Central PMCID: PMC3292433.
• Pak J, Tucci VT, Vincent AL, Sandin RL, Greene JN. Mucormycosis in immunochallenged patients. J Emerg Trauma Shock. 2008 Jul;1(2):106-13. doi: 10.4103/0974-2700.42203. PubMed PMID: 19561989; PubMed Central PMCID: PMC2700608.
• Quan C, Spellberg B. Mucormycosis, pseudallescheriasis, and other uncommon mold infections. Proc Am Thorac Soc. 2010 May;7(3):210-5. doi: 10.1513/pats.200906-033AL. Review. PubMed PMID: 20463250; PubMed Central PMCID: PMC3266012.

FOAM and web resources

• Radiopaedia — Pulmonary mucormycosis, Rhinocerebral mucormycosis,
• Radiology signs — Black turbinate sign