Mucormycosis

Facts You Should Know About Mucormycosis

Symptoms of mucormycosis depend on the area of the body affected by the fungal infection.
Symptoms of mucormycosis depend on the area of the body affected by the fungal infection.
  • Mucormycosis is a rare fungal infection caused by a group of molds called Mucoromycotina found in soil and decaying organic matter.
  • Mucormycosis is a serious illness and is more common in people with weakened immune systems.
  • Mucormycosis infection occurs in two ways: when people inhale fungal spores, as in the pulmonary or sinus form; and cutaneous, when fungus enters through an open wound on the skin.
  • Risk factors for developing mucormycosis include diabetes mellitus, cancer, long-term corticosteroid use, transplants, HIV/AIDS, skin trauma, excess iron, and injection drug use.
  • Mucormycosis signs and symptoms depend the part of the body affected by the fungus.
  • Symptoms of mucormycosis that affects the sinuses, brain, and eyes include fever, nasal ulcers, stuffy nose, facial swelling, vision problems, sinus infection, and headache.
  • Symptoms of mucormycosis that affects the lungs include cough, shortness of breath, pneumonia, fever, and chest pain.
  • Symptoms and signs of mucormycosis that affects the skin include blisters or ulcers, black skin on the infected area, and pain, redness, swelling, or warmth around a wound.
  • Medical professionals diagnose mucormycosis with a medical history and physical exam. They may also take fluid or tissue samples send them to a lab. Other tests may include CT scan or MRI. There are no specific blood tests to detect mucormycosis.
  • Treatment of mucormycosis involves antifungal medications and sometimes surgical removal of affected tissue.
  • The prognosis of mucormycosis depends on a number of factors. The overall mortality rate is about 50%.
  • The fungi that cause mucormycosis are common in the environment, so it may not be possible to prevent inhaling fungal spores.

What Is Mucormycosis?

Mucormycosis (previously called zygomycosis) is a rare fungal infection of the sinuses, lungs, or skin caused by a group of molds called Mucoromycotina. These molds live in soil and in decaying organic matter, such as spoiled foods, leaves, compost piles, or rotten wood.

Mucormycosis is a serious illness and appears mainly in people with weakened immune systems.

What Causes Mucormycosis?

Sorangia of a Mucor spp
Picture of sporangia of a Mucor spp. fungus; SOURCE: CDC/Dr. Lucille K. Georg

A group of molds called Mucoromycotina cause Mucormycosis. The genera of mold most commonly seen in human infections include Rhizopus and Mucor.

Other genera of Mucoromycotina that less commonly cause infection are Rhizomucor, Cunninghamella, Lichtheimia (previously called Absidia), Saksenaea, and Apophysomyces.

Mucormycosis infection occurs in two ways:

  • Pulmonary or sinus form: When people inhale the fungal spores, the infection can develop in the sinuses and lungs. It can also affect the eyes, face, and rarely, the central nervous system.
  • Cutaneous form: The fungus enters the skin through cuts, scrapes, burns, or other open wounds.

Is Mucormycosis Contagious?

Mucormycosis is not contagious and cannot spread from person-to-person contact.

What Is the Incubation Period for Mucormycosis?

The mucormycosis incubation period is unknown.

What Are Risk Factors for Mucormycosis?

Most patients with mucormycosis have a weakened immune system or other underlying medical condition disease that predisposes them to infection. Risk factors for mucormycosis include the following:

What Are Mucormycosis Symptoms and Signs?

Mucormycosis signs and symptoms depend the part of the body the fungus affects.

Symptoms and signs of rhinocerebral mucormycosis affect the sinuses, brain, and eyes and include the following:

  • Fever
  • Nasal ulcers
  • Stuffy nose
  • Facial swelling
  • Vision problems
  • Sinus infection
  • Headache

Symptoms of pulmonary mucormycosis affect the lungs and include

Signs and symptoms of cutaneous mucormycosis affect the skin and include

  • blisters or ulcers,
  • black skin on the infected area, and
  • pain, redness, swelling, or warmth around a wound.

Gastrointestinal mucormycosis that affects the digestive tract is rare and severe. Symptoms and signs include

How Do Medical Professionals Diagnose Mucormycosis?

A doctor will take a medical history and perform a physical exam, noting your symptoms.

If mucormycosis is suspected in the lungs or sinuses, a health care professional may perform an endoscopy (a thin tube with a camera on the end is inserted into the body) to take a sample of fluid from the lungs or a tissue biopsy to send to a lab. A medical professional will examine the fluid or tissue to detect evidence of mucormycosis under a microscope or in a fungal culture. It may be necessary to perform a CT scan or MRI of the lungs or sinuses.

There are no specific blood tests that can detect mucormycosis.

What Is the Treatment for Mucormycosis?

Treatment of mucormycosis involves antifungal medications and sometimes surgical removal of affected tissue.

Early intervention with antifungal medications improves the outcome of infection with mucormycosis. The initial therapy is usually amphotericin B, administered intravenously. Once patients have responded to amphotericin B, or for those who cannot tolerate it, oral posaconazole (Noxafil) or isavuconazole (Cresemba) may be used.

Mucormycosis often requires surgery to remove infected tissue.

There is currently no vaccine to prevent mucormycosis.

What Is the Prognosis for Mucormycosis?

The prognosis of mucormycosis depends on a number of factors, such as how quickly the diagnosis is made and how soon treatment is started, the site of infection, and the patient's underlying medical condition. It is a difficult infection to cure.

Early intervention with antifungal medications improves the outcome of infection but the overall mortality rate is about 50%. The mortality rate for rhino-orbital-cerebral (sinuses-eyes-brain) mucormycosis ranges from 25%-62%. Patients with infection confined to the sinuses have the best chance of a good outcome. Patients with brain, cavernous sinus, or carotid involvement are more likely to have a poor outcome. Patients with pulmonary mucormycosis have mortality rates as high as 87%. Disseminated mucormycosis has a 96% mortality rate.

Surgical debridement to remove affected tissue can be disfiguring.

Is It Possible to Prevent Mucormycosis?

The fungi that cause mucormycosis are common in the environment, so it may not be possible to prevent inhalation of the fungal spores.

For those with weakened immune systems, the Centers for Disease Control (CDC) recommends protecting yourself from the environment (while these actions are recommended, they have not been proven to prevent the disease):

  • Avoid construction areas or places with a lot of dust. If you can't avoid these areas, wear a type of facemask called an N95 respirator.
  • Avoid yard work or gardening or coming into contact with soil and dust. If you can't avoid this, wear gloves, closed shoes, long pants, and a long-sleeved shirt.
  • Clean cuts and other skin injuries well with soap and water, especially when exposed to soil or dust.
  • If you are at high risk of developing mucormycosis, a medical professional may prescribe antifungal medication for prevention of infection.

Diagnosis of Mucormycosis

CT Scan

CT, or CAT scans, are special X-ray tests that produce cross-sectional images of the body using X-rays and a computer. CT scans are also referred to as computerized axial tomography. CT was developed independently by a British engineer named Sir Godfrey Hounsfield and Dr. Alan Cormack. It has become a mainstay for diagnosing medical diseases. For their work, Hounsfield and Cormack were jointly awarded the Nobel Prize in 1979.

References
Cox, Gary M. "Mucormycosis (zygomycosis)." Jan. 4, 2021. <https://www.uptodate.com/contents/mucormycosis-zygomycosis?search=Mucormycosis&source=search_result&selectedTitle=1~77&usage_type=default&display_rank=1>.

Rammaert, Blandine, et al. "Healthcare-Associated Mucormycosis." Clinical Infectious Diseases 54, Issue suppl_1 Feb. 1, 2012: S44-S54. <https://academic.oup.com/cid/article/54/suppl_1/S44/285017 >.

United States. Centers for Disease Control and Prevention. "Mucormycosis." Feb. 25, 2021. <https://www.cdc.gov/fungal/diseases/mucormycosis/index.html>.