Association of Serum Iron Studies in COVID Associated Mucormycosis with Stage of the Disease

Mucormycosis (Zygomycosis) is a rare and lethal invasive fungal infection, often acute and extremely severe caused by opportunist and ubiquitous fungi belonging to the class Phygomycetes, subclass Zygomycetes, order Mucorales, family Mucoraceae. India has reported surge in cases of post COVID 19 Mucormycosis over the past few months due to the increasing frequency of risk factors like corticosteroid therapy, uncontrolled diabetes, DKA, neutropenia and iron overload. Patients with a history of COVID-19 infection are at increased risk of developing fungal infections like Mucormycosis. The emergence of COVID-19 associated mucormycosis (CAM) across several nations, particularly India, warrants a detailed study to identify potential contributing factors.

Material: This cross sectional study conducted at Bowring and Lady Curzon Hospital, Bangalore, involving 75 subjects diagnosed with CAM either clinically, radiological or microbiologically. The objective was to study the clinical profile of patients with COVID associated Mucormycosis and to correlate the levels of Serum ferritin and iron profile with severity and extent of disease in COVID associated Mucormycosis patients Data was collected on demographic details, co morbidities, vaccination status, history of treatment with remedesvir, oxygen therapy or steroid use, complications of past COVID 19 infection and stage of current Mucormycosis infection. Clinical outcome of the patients measured based on Iron profile, length of hospital stay, need for ICU admission, presence of diabetic ketoacidosis and mortality. The blood investigations which included were CBC with differential leukocyte count, qCRP, FBS, PPBS, HbA1c serum iron studies and serum ferritin.

Observation: The mean age of the subjects was 48.19 with 52 males, 23 females. Among 75 patients with CAM, 90.7% were unvaccinated against COVID-19, 62.7% had oxygen usage and steroid therapy, 44% had use of remedesvir. Most common co morbidity was diabetes mellitus 60% with 20% of patients having DKA. Rhino orbital-cerebral mucormycosis(Stage 4- 44.6%) was the most common clinical presentation. The mean serum iron (50.37) and TIBC (255.37) were significantly higher in Stage 4 CAM cases compared with less invasive stage 2 CAM cases. Patients with Stage 4 CAM had elevated levels of inflammatory markers LDH (292) DDimer (457) CRP(74.64). Case fatality rates of CAM was 12%.

Conclusion: The results of this study revealed significant correlation between the clinical severity of CAM and higher mortality, increased serum iron levels and inflammatory markers in this population of patients. Therefore, patients with elevated levels of available serum iron are uniquely susceptible to mucormycosis infection, suggesting dysregulated iron metabolism in its pathogenesis.