Case Presentation: A 53-year-old male, post-allogeneic hematopoietic stem cell transplant (HSCT) for relapsed acute myeloid leukemia (AML) presented to an outside hospital with high fevers, frontal lobe headaches, and blood-tinged sinus drainage, two weeks after completing chemotherapy. Days later, the patient was transferred to our hospital for advanced care, reporting continued fevers (up to 38.6oC), headaches and nasal secretions. Lab results showed pancytopenia (WBC 400/mm3, hemoglobin 11.2 g/dL, and platelets 30,000/mm3). Alongside standard prophylaxis (acyclovir, fluconazole, and trimethoprim-sulfamethoxazole) and reduced immunosuppressive therapy, empirical antimicrobials were initiated for neutropenic fever. Concerns for invasive fungal sinusitis (IFS) prompted a CT scan, revealing worsening mucosal disease without bony erosions or extension. Antimicrobials were broadened and posaconazole was initiated for antifungal coverage. Nasal endoscopy revealed meatus crusting with pale mucosa, and biopsy confirmed IFS with worrisome elements suggesting mucormycosis. This led to dual mold therapy initiation with liposomal Amphotericin B and Isavuconazonium sulfate (Cresemba). Serum Fungitell and serum Aspergillus antigen returned with values of 42 pg/mL and < 0.500 respectively. Subsequent nasal endoscopy, debridement, and bilateral functional endoscopic sinus surgery (FESS) revealed Aspergillus niger in cultures, contrary to initial histopathological observations. Following improvement on antifungal therapy and surgical management, the patient was discharged on outpatient Cresemba treatment. However, upon returning weeks later with persistent symptoms, worsening sinus changes and orbital extension were observed on CT scan, requiring extensive regional removal and retrobulbar Amphotericin B injections. Despite symptomatic improvement, the patient’s critical condition and prolonged neutropenia led to the decision to transition to home hospice care.
Discussion: This report highlights a rare presentation of invasive fungal sinusitis with Aspergillus niger in a relapsed AML patient post-HSCT. In immunocompromised individuals, especially those with hematological malignancies and history allogeneic HSCT, IFS poses a grave and fatal threat, particularly amidst profound neutropenia [1]. While invasive aspergillosis (IA), a subtype of IFS, remains rare in immunocompetent individuals, allogeneic HSCT recipients face a notable surge in incidence ranging from 8 to 15 percent [2]. Despite the rapid onset and progression of IFS, its clinical presentation is subtle and insidious, contributing to mortality rates up to 80% [3]. Early detection becomes imperative, demanding heightened clinical suspicion for a timely diagnosis, a critical prognostic component, with delays in therapy ≥ 6 days linked to a twofold increase in mortality [4,5]. Employing a multidisciplinary approach with prompt surgical debridement and systemic antifungal therapy is paramount. ENT evaluation triggered after five days of febrile neutropenia, regardless of symptoms, may improve outcomes [6]. Limited data suggests careful consideration of mold-active prophylaxis (e.g., posaconazole or voriconazole) for high-risk allogeneic HSCT patients [7].
Conclusions: In conclusion, this case underscores the importance of heighted clinical suspicion, multidisciplinary care, proactive management strategies, and ongoing research for optimal management of IFS in allogeneic HSCT recipients.