Black Fungus: Symptoms, Causes & Treatment

Black fungus, medically known as mucormycosis, is a rare but serious fungal infection. It can cause symptoms such as headache, fever, and discharge from the eyes or nose.

In severe cases, black fungus may lead to seizures and loss of consciousness. The infection is caused by several types of mucormycete molds, including Rhizopus spp. and Lichtheimia spp., which are found in soil and decaying organic matter.

Anyone with symptoms of mucormycosis should seek immediate medical care. Early diagnosis and appropriate treatment are important for reducing the risk of serious or life-threatening complications.

Common symptoms

The symptoms of mucormycosis vary depending on the person’s immune system and the part of the body affected. They may include:

• Stuffy nose

• Sinus pain and headache

• Fever

• Nasal discharge or nosebleeds

• Changes in vision and swelling around the eyes

• Swelling on one side of the face

• Coughing up blood or mucus

• Seizures, confusion, and difficulty speaking

• Chest pain and shortness of breath

When the fungus affects the skin, it can cause red, firm, swollen, and painful lesions. These may develop into blisters or open sores with a blackened appearance.

In more advanced cases, the skin may turn bluish and the fingers may appear purple because the lung infection reduces oxygen levels in the blood.

If the infection is not diagnosed and treated, the fungus can quickly spread to other organs. This is especially dangerous for people with severely weakened immune systems, as the infection may reach the kidneys and heart and become life-threatening.

Main types

The types of mucormycosis are classified according to the part of the body affected:

• Rhinocerebral mucormycosis: This is the most common form of the infection. The fungus affects the nose, sinuses, eyes, mouth, and brain.
• Pulmonary mucormycosis: In this form, the fungus affects the lungs. It is the second most common type of mucormycosis.
• Cutaneous mucormycosis: This type affects the skin. The infection may spread through the skin and reach the muscles.
• Gastrointestinal mucormycosis: In this form, the fungus affects the gastrointestinal tract.

Disseminated mucormycosis is another, less common form of the infection. It occurs when the infection spreads through the bloodstream and reaches several organs, such as the heart, kidneys, spleen, and brain.

Confirming a diagnosis

Mucormycosis is diagnosed based on the person’s symptoms, medical history, physical examination, imaging tests, and laboratory findings. The healthcare team may include specialists in infectious diseases, radiology, surgery, or other areas, depending on the part of the body affected.

The doctor may order a CT scan or MRI to locate the infection and determine how far it has spread. MRI may be preferred when the eyes or brain may be affected.

To confirm the diagnosis, a sample of tissue or fluid from the affected area is usually examined under a microscope and tested with a fungal culture. A biopsy is often needed, while sputum testing may be helpful when pulmonary mucormycosis is suspected.

In some cases, specialized molecular tests, such as PCR, may be used to help identify the fungal species.

Possible causes

Mucormycosis is caused by several types of molds known as mucormycetes. These include Rhizopus spp., Mucor spp., Lichtheimia spp., Rhizomucor spp., Cunninghamella spp., and Apophysomyces spp.

These molds are commonly found in the environment, especially in soil and decaying organic matter, such as leaves, compost, and rotting wood.

Mucormycosis can develop when a person inhales fungal spores or consumes contaminated food or drinks. The spores can also enter the body through damaged skin, such as a cut, wound, burn, or surgical incision.

Risk factors

The fungi that cause mucormycosis are opportunistic and mainly affect people with weakened immune defenses.

People at higher risk include those with uncontrolled diabetes, cancer, persistent neutropenia, malnutrition, or a history of organ or stem cell transplant. According to the CDC, long-term corticosteroid use can also increase the risk.

Mucormycosis has also been reported in people with severe COVID-19, particularly in the presence of uncontrolled diabetes or corticosteroid treatment.

Treatment options

Treatment for black fungus (mucormycosis) should start as early as possible and is usually coordinated by a multidisciplinary healthcare team. According to the CDC, prompt management typically includes antifungal medication, surgery, and careful control of underlying health conditions.

Treatment may involve:

• Intravenous antifungal medication, most often amphotericin B, followed by or replaced with an oral or intravenous antifungal such as posaconazole, depending on the person’s clinical status

• Surgery to remove dead and infected tissue (surgical debridement)

• Management of underlying health problems, which may include controlling blood sugar levels and reducing or stopping corticosteroid medicines under medical supervision

Treatment often continues for several weeks or months. The duration depends on where the infection is located, how severe it is, how well the person responds to therapy, and whether underlying risk factors have been brought under control.