Saksenaea oblongispora Rhinosinusitis in Advanced HIV: A Rare and Lethal Mucormycosis.

Mucormycosis is a severe invasive infection caused by the Mucorales fungi. The most frequently implicated genera are Rhizopus species, Mucor species, and Lichtheimia species. These fungi do not typically cause infections in immunocompetent individuals. Risk factors include diabetes mellitus, malignancies, transplant recipients, and current or past COVID-19 infection. Mucorales have also been linked to outbreaks in healthcare settings and following natural disasters. We describe a case of rapidly progressing rhinosinusitis in a patient with advanced HIV infection due to Saksenaea oblongispora, a rare cause of mucormycosis that, in contrast to the other Mucorales, primarily affects immunocompetent hosts following traumatic inoculation. A 32-year-old male patient presented with right-sided facial swelling. His clinical condition deteriorated rapidly. Biopsies and computerized tomography (CT) of the brain and sinuses were performed. Tuberculosis and bacterial workups were negative. Histological examination showed thick-walled angioinvasive fungal elements. Fungal cultures were positive. Molecular testing identified the organism as S. oblongispora. Due to his rapid deterioration, he neither underwent surgical intervention nor received any antifungal therapy and subsequently demised. This is the first case of S. oblongispora infection described in sub-Saharan Africa and in the setting of HIV. Infection by this fungus accounts for approximately 3% of human mucormycosis cases. S. oblongispora-associated rhinosinusitis is extremely uncommon and has been associated with rapid progression with high morbidity and mortality. A combination of different testing platforms was required to make a diagnosis. This case emphasizes the challenge of diagnosing invasive mold infections timeously. A high index of suspicion, combined with a multidisciplinary diagnostic and treatment approach, is essential for the management of these infections.