Mucormycosis a rare but rising fungal infection in post-COVID-19 patients
Mucormycosis, a potentially life-threatening fungal infection, is adding to India’s COVID-19-related death toll.
It typically affects patients recovering from COVID-19 who are immunocompromised due to COVID or by the use of steroids and/or concomitant diabetes.
“In the most common form, it colonizes the nose, the sinuses and the eyes, and from there it makes its way to the brain,” Sundaram Natarajan, MD, said in an interview with Healio/OSN.
Mucor is a mold commonly found in wet, damp areas, including soil, damp walls of old buildings, manure, and decaying fruits and vegetables. Due to high affinity for blood vessels, mucor infection blocks blood flow, causing ischemia, tissue infarction and necrosis. A healthy immune system can fight it off, but it spreads fast in immunocompromised individuals, causing death in a high percentage of cases. As it spreads to the eye, it rapidly causes vision loss and blindness, and enucleation must be performed to prevent deadly invasion of the brain.
Mucormycosis is a rare infection, but sporadic cases and small outbreaks have been reported all over the world. Now, alongside with the dramatic surge of COVID-19 in India, the number of cases of mucormycosis has risen accordingly.
“The officially reported cases are over 4,000 in Maharashtra, a state in India, but this is for sure an underestimation, and more likely they are thousands. We are currently launching a survey in collaboration with the ENT surgeons and dental surgeons of India,” Natarajan said.
The perfect storm
The combination of COVID-19, corticosteroid therapy and diabetes creates the perfect storm in which mucormycosis takes roots and thrives. Corticosteroids are a life-saving treatment used to reduce the dysregulated immune response observed in patients with COVID-19. However, they increase the blood sugar level, and fungi enjoy the sugar, Natarajan said. Hyperglycemia in patients with diabetes creates an even more favorable environment.
“Diabetes affects many people in India and, due to the weakened immune system, predisposes to more severe COVID-19 infection, which is typically treated with corticosteroids. With this combination of dysfunctional immune system — that is, a common denominator of COVID-19 and diabetes — plus the use of corticosteroids, the risk of mucormycosis increases exponentially,” Natarajan said.
In addition, COVID-19 damages and weakens the superior respiratory tract and the eye, increasing susceptibility to fungal infection. Another contributing factor is the use of antibiotics, also commonly prescribed in patients with COVID-19 to fight secondary infections, he said.
Prompt diagnosis, aggressive treatment
Common symptoms of mucormycosis that an eye doctor can easily detect are eyelid edema, orbital pain, eyelid ptosis, protruding eyes, ocular motility restrictions, double vision and sudden vision loss. They may be preceded by or associated with other symptoms, such as dental pain, stuffy nose, poor smell, nasal discharge and bleeding, facial paresthesia and palsy.
“It is extremely important to promptly diagnose and treat the infection because it evolves very rapidly. Post-COVID-19 patients need to be aware that they should watch for any suspicious symptoms and immediately contact the doctor,” Natarajan said.
Imaging, microscopy and histopathological analysis of biopsy specimens are used to confirm the clinical diagnosis. MRI with contrast can help detect the affected areas and guide surgical intervention to remove the necrotic tissue. Repeated debridement may be needed, and more severe cases may require orbital exenteration and removal of the sinuses. At the same time, aggressive antifungal therapy should be promptly started.
“We need to raise awareness on this devastating threat among people, doctors and ophthalmologists,” Natarajan said.
He said it is necessary to educate patients on using precautions, such as hand and ambient hygiene, avoiding contact with dirty surfaces and wearing masks to avoid breathing mucor spores. Post-COVID patients who are treated with steroids and patients with diabetes should be even more careful. Physicians, on the other hand, should avoid prescribing corticosteroids, tocilizumab and antibiotics, if they are not strictly necessary.
“Since mucormycosis involves the eye, ophthalmologists may be the first to see the signs of mucormycosis. It is important for them to be aware of this potential infection, taking it into account in any differential diagnosis and acting promptly with medical and surgical treatment. Hence, our ophthalmologists’ association is organizing CME for ophthalmologists, ENT surgeons and physicians/diabetologists. Delays can be fatal to vision and life,” Natarajan said.
- For more information:
- Sundaram Natarajan, MD, can be reached at Aditya Jyot Eye Hospital, Plot No. 153, Road No. 9, Mumbai, Mahashtra 400031, India; email: email@example.com.