Oral mycetoma of the upper lip nasolabial region in a healthy host: A case report and minireview of diagnostic and therapeutic considerations

Oral mycetoma, or fungal ball, is a rare entity typically affecting immunocompromised individuals; its presentation in the oral cavity, particularly the upper lip of healthy hosts, is exceedingly rare. We report a unique instance of upper lip nasolabial mycetoma in a 60-year-old immunocompetent male presenting with painless swelling. Initial imaging (magnetic resonance imaging/ultrasonography) revealed a well-defined, fluid-filled nodule, mimicking a benign neoplasm or mucocele. Excisional biopsy and subsequent histopathological examination with Grocott methenamine silver staining definitively diagnosed mycetoma, revealing encapsulated abscesses with filamentous fungal hyphae, suggestive of Aspergillus etiology. This case highlights the diagnostic ambiguity of atypical fungal infections in immunocompetent patients and underscores the necessity to consider fungal etiologies in the differential diagnosis of oral lesions, irrespective of patient immune status. Histopathology remains crucial for definitive diagnosis and appropriate management. Surgical excision with 1-year follow-up proved to be an effective therapeutic modality for localized oral fungal mycetoma in this healthy individual.