Mucormycosis (Black Fungus Eschar) Causes, Symptoms, Invesigations, Treatment

Mucormycosis

Causes Of Mucormycosis:-

Most common-non-Aspergillus invasive mold infection.

Mucormycosis- opportunistic infections, caused by Rhizopus, Mucor, Lichtheimia & Cunninghamella.

Risk factors: hematologic malignancy (leukemia), diabetic ketoacidosis, chronic kidney disease, stem cell transplantation, solid organ transplantation, and treatment with corticosteroids (eg. used in COVID- 19 treatment), desferoxamine, or cytotoxic drugs, wound contamination by soil.

Symptoms Of Mucormycosis:-

Most common disease sites- Pulmonary, rhinocerebral, & skin.

Other orbital, gastrointestinal, disseminated, miscellaneous form involve bone, trachea, kidney, mediastinum, etc.

Invasive disease- sinuses, orbits, & lungs.

Necrosis by hyphal tissue invasion- hemoptysis, ulceration of the hard palate, nasal palate.

Eye or facial pain & facial numbness.

Fever absent in half of cases.

Cavernous sinus thrombosis development suggested by proptosis, chemosis, opthalmoplegia, vision loss.

Black necrotic eschar.

Pulmonary involvement leads to cough, dyspnoea, chest pain, often fever.

Investigations Of Mucormycosis:-

Biopsy of involved tissue – cornerstone of diagnosis, organisms- seen in tissues as broad, branching nonseptate hyphae.

No biochemical or blood cultures are helpful.

Molecular identification (like PCR) from tissue and/or mass spectrometry-base detection of a panfungal serum disaccharide.

Chest CT- A reverse “halo sign”:- (focal area of ground glass diminution- surrounded by a ring of consolidation).

Cultures are frequently negative.

Treatment Of Mucormycosis:-

Removal of predisposing conditions, surgical debridement, extensive repeated surgical removal of nonperfused, necrotic tissue, and prompt antifungal treatment.

Early use of Lipid preparation of I/V Liposomal amphotericin B (5–10 mg/kg) & higher doses given for CNS involvement.

Oral posaconazole 300mg 12 hourly for 1 day then 300 mg/day or

Oral or I/V Isavuconazole 200 mg every 8 hours for 1–2 days, then 200 mg daily.

in less severe disease,

step-down therapy after stabilization of disease, or

salvage therapy as poor response or tolerance to amphotericin.

Mucormycosis is rapidly fatal disease without treatment.

Prolonged course of treatment depends on clinician.

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