Diagnosis of invasive Mucormycosis on Histopathological examination at a tertiary referral hospital

Abstract

This study is conducted with an aim to Diagnosis of invasive Mucormycosis on Histopathological examination at a tertiary referral hospital. Rhino cerebral Mucormycosis is the current life-threatening infection commonly affecting immunocompromised patients especially post COVID-19 within 6 weeks having poor glycemic control, Intravenous drug users, ICU patients, post chemotherapy, iron overload, persistent neutropenia and follow-up cases of hematological malignancies. It affects the nasal and paranasal sinuses by air-borne spores producing the infection. A prospective case series conducted at the department of pathology, KAMSRC ‘between’ May 1to September 30th 2021 with a study population of 27 cases. Variables included age, gender, and history of covid, duration and development of symptoms, Clinical presentation, clinical diagnosis, co-morbidities, histopathological examination and microbiological correlation. The most prevalent isolated agent is Mucor (48.1%) followed by Rhizopus (18.5%), Aspergillus (11.1%) and mixed mucor with aspergillus (11.1%).A prospective case series conducted at the department of pathology, KAMSRC, reported 27 cases of post covid-19 Mucormycosis aged 30-68 years. Clinical features at presentation included unilateral facial pain with proptosis (80%), loss of vision, headache, nasal crusting, Cough with dyspnea and mild fever. All cases were admitted in ICU with severity in symptoms with 7 deaths recorded during treatment (25.9%). Immunofluorescence with Robin blue/Calcofluor white stainfor fungal elements was also combined to highlight Mucor species.Fungal cultures were diagnostic for fungal elements obtained after 48hrs on Sabouraud’s/Potato dextrose agar(SDA/PDA). Three cases were negative for fungal elements withonly dense mixed inflammatory infiltrate admixed necrosis. Correlation with KOH mount & fungal culture on SDA/PDA showed 13 cases of mucor, 5 cases of rhizopus, 3 cases of aspergillus & 2 cases of mucor with aspergillus growth, 3 cases were negative with no fungal growth. Also correlated with the microbiology department where nasal crusting and nasal tissue was obtained for fungal elements for KOH wet mount and fungal culture. KOH wet mount microscopy revealed Broad aseptate hyphae with wide angle branching suggestive of Mucormycosis. Simultaneous analytical study of CBP showed raised total WBC counts in 4 individuals (19,620-24,670 cumm) with others having normal CBC.CRP was in the range of 32-68mg/dl with ESR 35-98 mm/hr. : Understanding the mechanism of host innate immunity and specific preventive strategies are important for favorable prognosis. Histopathological examination aids in early diagnosis of Mucormycosis.