Mucormycosis

Mucormycosis (Zygomycosis) is an opportunistic fungal infections caused by Mucor and Rhizopus. These fungi grow in decaying matter. Mucormycosis is a disease of those who are severely compromised by diabetes, trauma, or organ transplantation. Rhinocerebral/sinus disease is most common.

CASES/YEAR
500 (US); 10,000 (Global)
CATEGORY
AGENT TYPE
Fungi (Opportunistic Molds)
OTHER NAMES
Zygomycosis; Fungal infections caused by Mucor and Rhizopus;
ACUITY
Subacute/Chronic
INCUBATION
Unknown; Mucormycosis spreads rapidly in the debilitated patient in which case it is, "the most fulminant fungal infection known." [CCDM, p. 416-7] Estimated: 3 days to 3 months;
INITIAL SYMPTOMS
Sinusitis with progression to fever, diplopia, and lethargy; Severe pneumonia; Necrotic skin ulcers; Gastrointestinal ulcers;
PRECAUTIONS
Standard; "Not transmitted from person to person." [CDC 2007 Guideline for Isolation Precautions]
COMMENTS
FINDINGS
These fungi are common in the environment growing in decaying matter. Mucormycosis is a disease of those who are severely compromised by diabetes, trauma, or organ transplantation. Rhinocerebral/sinus disease is most common (34% of patients) followed by pulmonary (22%), cutaneous (18%), or disseminated disease (3%), and kidney or gastrointestinal disease (7%). Patients with rhinocerebral disease often have facial pain, headache, fever, and orbital cellulitis. Meningitis is rare. Tissue necrosis is evident in ulcers that turn black. The infection may cause cranial nerve dysfunction and cerebral abscesses. Invasion of the cavernous sinus, ophthalmic artery, or orbit causes blindness. IV drug abusers are susceptible to endocarditis and brain abscesses. [PPID, p. 1253, 3121-5] Most culture positive cases of mucormycosis are caused by species of Rhizopus. [CDCM, p. 694] Lung infections and pleural effusions occur in immunocompromised patients (severe neutropenia or diabetes mellitus). Other sites of infection include the mediastinum. [Cohen, p. 1697-8] Causes allergic respiratory symptoms in the healthy and invasive sinusitis and pneumonia in the immunocompromised; Other findings are hematemesis, hematochezia, seizures, and sputum production. Hematuria, fever, and flank pain may indicate renal infection after IV drug use or central venous catheter. [Guerrant, p. 597-600] "Progressive extension of necrosis to the brain can cause signs of cavernous sinus thrombosis, seizures, aphasia, or hemiplegia." [Merck Manual, p. 1575]

EPIDEMIOLOGY:
Mucormycosis is acquired by inhalation of spores; Risk factors include poorly controlled diabetes, neutropenia, deferoxamine therapy, and glucocorticoid therapy. [Harrisons, p. 598] Acquired mainly by inhalation; Also by ingestion and skin trauma; Mortality rates for underlying condition: diabetes ~40-50%; cancer ~66%; none ~35%; [ABX Guide: Zygomycetes] Mortality was 62% in one series of patients with rhinocerebral mucormycosis. [Cecil, p. 2057] "Rhizopus species have also been implicated in an allergic alveolitis described in farm workers as well as Scandinavian sawmill workers (wood-trimmer's disease." [PPID, p. 3123] See "Hypersensitivity pneumonitis."
DIAGNOSTIC
Notify lab that mucormycosis is suspected so that tissue sections instead of tissue homogenates can be cultured; Hyphae are ribbon-like, aseptate, and branch at right angles. [Harrisons, p. 598-9]
SCOPE
Global
SIGNS & SYMPTOMS
  • >fever
  • E epistaxis
  • E nasal ulcers
  • E rhinitis
  • G abdominal mass
  • G abdominal pain
  • G blood in stool
  • G diarrhea
  • G hematemesis
  • G nausea, vomiting
  • H leukocytosis
  • N headache
  • N lethargy
  • N muscle weakness
  • N seizure
  • R chest pain
  • R cough
  • R dyspnea
  • R hemoptysis
  • R sputum production
  • S pustule
  • S ulcer of skin
  • U hematuria
  • X cystic or cavitary lesions
  • X lung infiltrates
  • X pleural effusions
  • *blindness
  • *brain abscess or lesion
  • *cranial neuropathy
  • *endocarditis
  • *mediastinitis
  • *meningitis
  • *osteomyelitis
  • *pancreatitis
  • *paralysis
  • *pneumonia
ANTIMICROBIC

Yes

VACCINE

No

ENTRY
Inhalation
RESERVOIR
RISK FACTORS
  • Cancer patients
  • Injection drug users
REFERENCES FOR CASES/YEAR
1. (US) Occurs in immunosuppressed patients (diabetes, transplantation, neutropenia, and malignancy); [Harrison ID, p. 1020] Estimated at about 500 cases per year in US; [Gorbach, p. 272]
2. (Global) Calculate: 20 x 500 (US cases/yr) = 10,000;