Coronavirus disease-associated mucormycosis (CAM): A case control study during the outbreak in India

The recent second wave of COVID-19 cases in India has been marked by an unexpected increase in cases of mucormycosis reported in the context of COVID illness. Herein we aim to identify risk factors that may explain the sudden surge of cases and help develop preventive strategies.

We performed a case-control study comparing cases diagnosed with CAM and those who had recovered from COVID-19 without developing mucormycosis (controls). Information on comorbidities, glycemic control, and practices related to COVID-19 treatment was recorded.

100 patients of CAM (cases) and 150 patients of COVID-19 without mucormycosis (controls) were included in the study. The spectrum of involvement of CAM cases included rhino-sinus (n=98, 98%), rhino orbital (n=58, 58%), rhino-orbito-cerebral (n=29, 29%). In CAM group symptoms of mucormycosis began a mean of 13.46 days after onset of COVID-19. The mean age of the CAM study group was 51.16 years with 69 males (69%) and 31 females (31.0). The most frequent comorbidities seen in our study population was diabetes (n=113, 45.2%) and hypertension (n=54, 21.6%). Diabetes was significantly more frequent among cases than controls (89% vs 24%, p <0.001). 31% of patients in CAM case group showed a common practise of steam inhalation during covid illness. Most common symptom reported in CAM was related to the eye which included eye pain (58%), lid swelling (54%), eye swelling (47%). Sino-nasal symptoms were nasal discharge (25%), nasal stuffiness (21%), and epistaxis (4%). Other common symptoms were headache (51%) and facial pain (36%). On examination of nasal cavity, crusting and ulceration were present in 83% patients. Eye involvement was present in 60% of cases, of which 27% of cases had vision loss. For definitive diagnosis of CAM, Potassium hydroxide (KOH) mount was positive for aseptate hyphae in 31 patients (31%). Use of systemic steroids for the management of COVID-19, was more frequent in CAM case group than control group (n=70, 70%). The CAM case group showed mean Hba1c of 10.7 ± 2.45, mean Serum Iron levels was 49.01 ± 18.69, mean ferritin was 913.37, mean CRP was 131.56 and mean LDH was 428.70.

Overzealous use of steroids, uncontrolled sugars and repeated steam inhalation provided a favourable environment for the growth of mucormycosis. Judicious use of steroids and stringent glycemic control are vital to preventing mucormycosis.