Diagnostic and Therapeutic Paradoxes in PCR-Positive, Histopathology-Negative CNS Aspergillosis in A Patient with HIV and Hodgkin Lymphoma.

Abstract

Background: Invasive central nervous system (CNS) aspergillosis is rare among human immunodeficiency virus (HIV)-positive patients due to preserved neutrophil function, despite significant CD4+ T-cell depletion. Diagnosis typically requires histopathologic confirmation, but polymerase chain reaction (PCR) testing has introduced new challenges due to its high sensitivity but limited specificity.

Case presentation: We describe a newly diagnosed 43-year-old HIV-positive male with concurrent Hodgkin lymphoma who presented with progressive neurological decline and a ring-enhancing brain lesion. While histopathological analysis of the brain biopsy demonstrated features of HIV-associated leukoencephalopathy, PCR testing paradoxically identified Aspergillus fumigatus; however, histopathological examination failed to demonstrate definitive fungal elements. Despite negative cerebrospinal fluid galactomannan and β-D-glucan assays, empiric voriconazole therapy was initiated in accordance with current treatment guidelines. Over the ensuing month, the patient returned with worsening neurologic status, radiographic lesion progression, and ultimately developed Torsades de Pointes, and multiorgan failure, resulting in death.

Discussion: This case underscores the diagnostic and therapeutic complexities of PCR-positive, histopathology-negative CNS aspergillosis in HIV. Overreliance on molecular results without confirmatory pathology may lead to unnecessary antifungal therapy and severe drug toxicity. Additionally, overlapping immunosuppressive conditions-such as HIV and lymphoma-complicate clinical interpretation and management.

Conclusion: In HIV-positive patients with CNS lesions, PCR detection of Aspergillus should not independently justify antifungal therapy. Histological confirmation and multidisciplinary evaluation are essential to avoid misdiagnosis and adverse outcomes. This case highlights the urgent need for more precise treatment guidelines on when to initiate and discontinue antifungal treatment in complex immunocompromised populations.

Learning points: Polymerase chain reaction positivity for Aspergillus in the absence of histopathologic confirmation presents a major diagnostic dilemma, particularly in human immunodeficiency virus (HIV)-positive patients, where overreliance on molecular diagnostics may lead to misdiagnosis, unnecessary antifungal exposure, and significant toxicity.Empiric antifungal treatment should be re-evaluated when central nervous system lesions progress or fail to improve, as prolonged use of agents like voriconazole can result in serious toxicity, including arrhythmias like Torsades de Pointes; clearer guidelines are needed to define when empiric treatment is appropriate in complex cases.HIV-positive patients with coexisting malignancy require a multidisciplinary, evidence-based approach, as overlapping immunosuppressive conditions can obscure diagnosis and complicate treatment decisions.