Background: Coronavirus disease 2019 (COVID-19) is an acute viral illness affecting multiple systems caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Ever since its first detection in Wuhan, China in Nov 2019, SARS-CoV-2 has infected over 220 million people causing more than 4.5 million deaths worldwide and the numbers are increasing.  Dexamethasone, a steroid has been used as a treatment of choice in COVID-19 pneumonia with hypoxia ever since the REMAP study demonstrated its effectiveness in reducing mortality . Tocilizumab is being used to mitigate the risk of a cytokine storm. Several opportunistic infections have been reported in patients with COVID-19. Mucormycosis has emerged during this second wave of the pandemic, particularly in South Asian countries. The risk and prevalence of this particular opportunistic fungal infection among COVID-19 patients are currently unknown. During the pre-pandemic era, the global cases of Mucormycosis varied from 0.005 to 1.7 per million population.  It is necessary to re-evaluate any changes in traditional risk factors associated with mucormycosis in the precedent of ongoing COVID-19 pandemic.
Methods: We searched electronic databases from inception until June 21, 2021, using keywords COVID-19, SARS-CoV-2, and mucormycosis or mucor or zygomycosis. Case reports and case series of both suspected and confirmed cases of COVID-19 infection were included in the study.
Results: A total of 115 COVID-19 patients were diagnosed with Mucormycosis. Diabetes Mellitus was the most common co-morbidity with 77.1 %, followed by hypertension (29.5%) and renal disease (14.3%). The average HbA1C level was 10.1%. 55.2 % of the patients had received dexamethasone for COVID-19 infection. Eighty patients (91.9%) had received some form of steroids to treat COVID-19 infection. 10 patients (11.5%) had received tocilizumab. A total of 8 patients (7.6%) were on chronic immunosuppressive therapy (excluding steroids that were prescribed to treat COVID-19) and 7 patients (6.7%) had hematological malignancies. 7 patients (6.7%) had a history of transplants and kidney transplantation was the most common among them.Sinuses were the most common site of mucormycosis in patients with COVID-19 infection at 79.4% with maxillary sinus (47.4%) being most commonly infected. Orbits were the second most prevalent site at 56.7 % and lungs were infected with mucor at 11.3 %. The average duration between the symptom onset or COVID-19 diagnosis and the mucormycosis was 16.15 days (range 2-90 days). Cavernous sinus was either infiltrated or encased in 14 patients (14.4%). Cerebral involvement was seen in terms of abscess, infarcts, or edema in 12 patients (12.4%). Only 76 patients had data on the outcomes, out of which 37 (48.7%) patients had died. Diabetes mellitus is still the most common co-morbidity similar to non-covid patients. Complications such as cavernous sinus thrombosis, cerebral infarcts, abscesses were common.
Conclusions: Diabetes mellitus is still the most common co-morbidity similar to non-covid patients. More than 90 % of the patients with mucormycosis had exposure to steroids. Indiscriminate use of steroids in patients need to be avoided and focus needs to be put on tight blood sugar control in diabetic patients. Despite advances in medical and surgical treatment options, the mortality rate was significantly higher in these patients. Studies are needed to confirm the role of the SARS-CoV-2 virus in causing immune dysfunction and mucormycosis.