A POST COVID-19 INFECTION: BLACK FUNGUS (MUCORMYCOSIS)

 

                       

Recently, several cases of mucormycosis in people with COVID-19 have been increasingly reported world-wide, in particular from India. The primary reason that appears to be facilitating Mucorales spores to germinate in people with COVID-19 is an ideal environment of low oxygen (hypoxia), high glucose (diabetes, new-onset hyperglycemia, steroid-induced hyperglycemia), acidic medium (metabolic acidosis, diabetic ketoacidosis [DKA]), high iron levels (increased ferritins) and decreased phagocytic activity of white blood cells (WBC) due to immunosuppression (SARS-CoV-2 mediated, steroid-mediated or background comorbidities) coupled with several other shared risk factors including prolonged hospitalization with or without mechanical ventilators.

The Indian government reported that more than 11,700 people were receiving care for mucormycosis as of 25 May 2021. Many Indian media outlets called it "black fungus" because of the black discoloration of dead and dying tissue the fungus causes. Even before the COVID-19 pandemic, rates of mucormycosis in India were estimated to be about 70 times higher than in the rest of the world. Due to its rapidly growing number of cases many Indian state governments have declared it an epidemic.

Mucormycosis (previously called zygomycosis) is a serious but rare fungal infection caused by a group of molds called mucormycetes. These molds live throughout the environment. Mucormycosis mainly affects people who have health problems, weak immunity or take medicines that lower the body’s ability to fight germs and sickness. It most commonly affects the sinuses or the lungs after inhaling fungal spores from the air. It can also occur on the skin after a cut, burn, or other type of skin injury.

Immunocompromising conditions are the main risk factor for mucormycosis. Patients with uncontrolled diabetes mellitus, especially those with ketoacidosis, are at high risk.

Doctors believe mucormycosis, which has an overall mortality rate of 50%, may be being triggered by the use of steroids, a life-saving treatment for severe and critically ill Covid-19 patients.

Steroids reduce inflammation in the lungs for Covid-19 and appear to help stop some of the damage that can happen when the body's immune system goes into overdrive to fight off coronavirus. But they also reduce immunity and push up blood sugar levels in both diabetics and non-diabetic Covid-19 patients. It's thought that this drop in immunity could be triggering these cases of mucormycosis.

 SIGNS AND SYMPTOMS OF MUCORMYCOSIS

Signs and indications of Mucormycosis rely upon the area in the body of the infection. Infection normally starts in the mouth or nose and enters the focal sensory system through the eyes.

In the event that the contagious contamination starts in the nose or sinus and reaches out to mind, side effects and signs may incorporate uneven eye torment or migraine, and might be joined by torment in the face, deadness, fever, loss of smell, a hindered nose or runny nose. The individual may seem to have sinusitis. The face may look swollen on one side, with quickly advancing "dark sores" across the nose or upper within mouth. One eye may look swollen and swelling, and vision might be blurred.

The symptoms of mucormycosis depend on where in the body the fungus is growing.  Contact your healthcare provider if you have symptoms that you think are related to mucormycosis.

Symptoms of rhinocerebral (sinus and brain) mucormycosis include:

• One-sided facial swelling
• Headache
• Nasal or sinus congestion
• Black lesions on nasal bridge or upper inside of mouth that quickly become more severe
• Fever

Symptoms of pulmonary (lung) mucormycosis include:

• Fever
• Cough
• Chest pain
• Shortness of breath

Cutaneous (skin) mucormycosis can look like blisters or ulcers, and the infected area may turn black. Other symptoms include pain, warmth, excessive redness, or swelling around a wound.

Symptoms of gastrointestinal mucormycosis include:

• Abdominal pain
• Nausea and vomiting
• Gastrointestinal bleeding

Disseminated mucormycosis typically occurs in people who are already sick from other medical conditions, so it can be difficult to know which symptoms are related to mucormycosis. Patients with disseminated infection in the brain can develop mental status changes or coma.

TESTING OF MUCORMYCOSIS

• Healthcare providers consider your medical history, symptoms, physical examinations, and laboratory tests when diagnosing mucormycosis. 
• Healthcare providers who suspect that you have mucormycosis in your lungs or sinuses might collect a sample of fluid from your respiratory system to send to a laboratory. 
• Your healthcare provider may perform a tissue biopsy, in which a small sample of affected tissue is analyzed in a laboratory for evidence of mucormycosis under a microscope or in a fungal culture. 
• You may also need imaging tests such as a CT scan of your lungs, sinuses, or other parts of your body, depending on the location of the suspected infection. 
• There are no specific blood tests to detect mucormycosis.

TREATMENT OF MUCOURMYCOSIS

Treatment involves a combination of antifungal drugs, surgically removing infecting tissue and correcting underlying medical problems such as diabetic ketoacidosis.

Medicines

Intravenous bag for antifungal medicine, usually Amphotericin B, Posaconazole, or Isavuconazole. Mucormycosis is a serious infection and needs to be treated with prescription antifungal medicine, usually Amphotericin B, Posaconazole, or Isavuconazole. These medicines are given through a vein (Amphotericin B, Posaconazole, Isavuconazole) or by mouth (Posaconazole, Isavuconazole). Other medicines, including fluconazole, voriconazole, and echinocandins, do not work against fungi that cause mucormycosis.

Surgery

Often, mucormycosis requires surgery to cut away the infected tissue. Surgery can be very drastic, and in some cases of disease involving the nasal cavity and the brain, removal of infected brain tissue may be required. Removal of the palate, nasal cavity, or eye structures can be very disfiguring. Sometimes more than one operation is required.

The prognosis (outcomes) of mucormycosis infections range from fair to poor; there is about a 50% death rate that rises to about 85% for rhinocerebral and GI infections.

WAYS TO PROTECT / PREVENT FROMMUCORMYCOSIS

It’s difficult to avoid breathing in fungal spores because the fungi that cause mucormycosis are common in the environment. There is no vaccine to prevent mucormycosis. For people who have weakened immune systems, there may be some ways to lower the chances of developing mucormycosis.

A)     Protect yourself from the environment

It’s important to note that although these actions are recommended, they haven’t been proven to prevent mucormycosis.

o    Try to avoid areas with a lot of dust like construction or excavation sites. If you can’t avoid these areas, wear an N95 respirator (a type of face mask) while you’re there. 

o    Avoid direct contact with water-damaged buildings and flood water after hurricanes and natural disasters.

o    Avoid activities that involve close contact to soil or dust, such as yard work or gardening. If this isn’t possible,

o    Wear shoes, long pants, and a long-sleeved shirt when doing outdoor activities such as gardening, yard work, or visiting wooded areas.

o    Wear gloves when handling materials such as soil, moss, or manure.

o    To reduce the chances of developing a skin infection, clean skin injuries well with soap and water, especially if they have been exposed to soil or dust.

B)      Antifungal medication

If you are at high risk for developing mucormycosis (for example, if you’ve had an organ transplant or a stem cell transplant), your healthcare provider may prescribe medication to prevent mucormycosis and other mold infections. Doctors and scientists are still learning about which transplant patients are at highest risk and how to best prevent fungal infections.

CONCLUSION

Mucormycosis isn’t contagious, so you can’t get it from an infected person. Self-care measures are the best way to prevent this type of infection. If you have a weakened immune system, it’s important to keep yourself safe outdoors. Wearing a mask while doing yardwork and bandaging all wounds until they heal will help prevent fungal infections.

You may also consider taking extra precautions during the summer and autumn months, when there’s an increased amount of the fungi in the environment. Preventive measures include wearing a face mask in dusty areas, washing hands, avoiding direct contact with water-damaged buildings, and protecting skin, feet, and hands where there is exposure to soil or manure such as gardening or certain outdoor work. In high-risk groups such as organ transplant, antifungal drugs may be given as a preventative.

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