II. Pathophysiology

  1. Opportunistic Fungal Infection
  2. Caused by filamentous molds of the order Mucorales (phyllum Zygomycota), ubiquitous in the environment
    1. Rhizopus
    2. Rhizomucor
    3. Mucor
    4. Lichtheimia
  3. Vascular invasion
    1. Risk of thrombosis and tissue infarction
  4. Transmission
    1. Contaminated food
    2. Spore inhalation (nose, lungs)
    3. Skin Wounds

III. Risk Factors

  1. Otherwise healthy patients represent <10% of cases
  2. Severe Immunocompromised State (developed countries)
    1. Hematologic Malignancy
    2. Organ Transplant
    3. Neutropenia
    4. Autoimmune disorders
    5. Defuroxamine Use (for iron chelation)
  3. Other associated conditions (esp. developing countries)
    1. Poorly controlled Diabetes Mellitus
    2. Trauma or Burn Injury

IV. Types: Based on Distribution

  1. Rhino-orbital-cerebral Mucormycosis (ROCM)
    1. Most common type in Diabetes Mellitus
    2. Aggressive invasion of sinuses, cranial bones and vasculature
  2. Pulmonary Mucormycosis
    1. Common type in Hematologic Malignancy
    2. Uncommon type in Diabetes Mellitus
  3. Cutaneous Mucormycosis
  4. Gastrointestinal Mucormycosis
  5. Disseminated Mucormycosis
    1. Common type in Hematologic Malignancy
  6. Mucormycosis of uncommon sites

V. Diagnosis

  1. Diagnosis is based on lesion histopathology, PCR and culture
    1. Mucorales are irregular, nonseptate hyphae and with branching at right angles
  2. Blood Cultures are typically negative

VI. Management

  1. Precautions
    1. Prompt management is critical to survival
    2. Mucormycosis may be rapidly progressive
    3. Prognosis may worsen with each day of delayed diagnosis
  2. First-Line Antifungals
    1. Amphotericin BLipid Formulation (LFAB)
  3. Alternative Antifungals (Triazoles)
    1. Posaconazole (POSA)
    2. Isavuconazole (ISAV)
  4. Surgical management (adjunctive)
    1. Surgical Debridement or excision

VII. Prognosis

  1. Localized, cutaneous Mucormycosis: 10-30% mortality
  2. Invasive Mucormycosis: 30-50% mortality
  3. Disseminated Mucormycosis: 90% mortality

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