Exploring complexity: A compelling case of chronic allergic fungal sinusitis caused by Alterna Alternata with intracranial expansion and orbital involvement in an immunocompetent male - An illuminating case study and in-depth literature review.

Allergic Fungal Rhinosinusitis (AFRS), is a rare IgE-mediated hypersensitivity its prevalence is in rising, challenging its historical rarity. This case study explores a unique presentation of AFRS caused by Alternaria alternata, on an immunocompetent 16-year-old male presenting with right exophthalmos, nasal obstruction, and visual acuity decline with a focus on its clinical complexities, complications involving intracranial expansion and orbital involvement, and its impact. The fungal invasion was completely eradicated through an endoscopic endonasal resection combined with frontal craniectomy and orbital roof reconstruction. The clinical diversity, complex presentations and challenges posed by pediatric cases underline the need for individualized management strategies. Furthermore, molecular techniques proved essential for the precise identification of Alternaria alternata as the causative organism.