Breaking the mold with newer diagnostic tools- A case series

ABSTRACT

Objectives: Aspergillus is a ubiquitous mold, which causes a wide spectrum of illnesses. Pulmonary disease is caused mainly by Aspergillus fumigatus. Pulmonary aspergillosis is a common infection in the immunocompromised, but it is also seen in patients with chronic debilitating diseases who require corticosteroids and/or immunosuppressive therapy. The aim of this work was to focus on the diagnosis of invasive pulmonary aspergillosis (IPA), with the use of a relatively new test, Galactomannan assay. Methods: We report a case series of 6 patients with suspected fungal infection over the course of 2020-2021. The diagnosis of IPA was obtained by use of galactomannan assay. Patients underwent routine sputum examination, and when indicated, bronchoscopy. Sputum and/or BAL fungal cultures were negative for all patients. Results: The patients mean age was 48.3±12 years. The most common clinical presentation was cough with expectoration. Comorbidities included past history of pulmonary tuberculosis (1), severe COVID-19(1), HIV infection (1), chronic kidney disease (1) and diabetes mellitus (2). Galactomannan levels were obtained in BAL in five patients, and serum in one patient. All patients were given voriconazole. Outcome was favourable in all patients. Conclusion: Galactomannan is a polysaccharide cell wall component of Aspergillus species which is released during fungal growth. ELISA is capable of detecting galactomannan levels at concentrations as low as 0.5ng/ mL. It is a non- invasive test with high specificity that can be used both for diagnosis as well as for monitoring of patients. Serum galactomannan levels, though diagnostic, become positive later in the disease. BAL galactomannan provides an early diagnosis.