Introduction: Human immunodeficiency virus (HIV) enters the brain early, where it can persist, evolve, and become compartmentalized. Central nervous system (CNS) disease can be attributed to HIV alone or to the complex interplay between the virus and other neurotropic pathogens. Aim: The current review aims to describe the direct impact of HIV on the brain as well as its relationship with other pathogens from a practitioner’s perspective, to provide a general clinical overview, brief workup, and, whenever possible, treatment guidance. Methods: A review of PubMed was conducted to identify studies on neuropathogenesis of HIV in relation to host responses. Furthermore, the interaction between the CNS pathogens and the host damage responses were revised in the setting of advanced and also well-controlled HIV infection. Results: Similar to other pathogens, HIV leads to CNS immune activation, inflammation, and viral persistence. Therefore, almost half of the infected individuals present with neurocognitive disorders, albeit mild. Compartmentalized HIV in the CNS can be responsible in a minority of cases for the dramatic presentation of symptomatic HIV escape. Disruption of the immune system secondary to HIV may reactivate latent infections or allow new pathogens to enter the CNS. Opportunistic infections with an inflammatory component are associated with elevated HIV loads in the cerebrospinal fluid and also with greater cognitive impairment. The inflammatory immune reconstitution syndrome associated with CNS opportunistic infections can be a life-threatening condition, which needs to be recognized and managed by efficiently controlling the pathogen burden and timely balanced combination antiretroviral therapy. Latent neurotropic pathogens can reactivate in the brain and mimic HIV-associated severe neurological diseases or contribute to neurocognitive impairment in the setting of stable HIV infection. Conclusions: As HIV can be responsible for considerable brain damage directly or by facilitating other pathogens, more effort is needed to recognize and manage HIV-associated CNS disorders and to eventually target HIV eradication from the brain.
Introduction: A group of approximately 15 Candida species are frequently found to be responsible for human invasive candidiasis, an infection that appears in patients with prolonged hospitalization, particularly in Intensive Care Units, and in immunosuppressed individuals. Given the considerable burden if not rapidly treated, clinicians face diagnostic challenges in distinguishing infection. The objective of this narrative review is to summarize the clinically applicable biomarkers used for invasive candidiasis and to evaluate their performance and create a diagnostic algorithm for clinical practice. Methods: This narrative review was conducted by searching PubMed and Scopus for studies published between 1990 and 2025, using keywords related to invasive candidiasis and non-culture diagnostic biomarkers. Clinical guidelines and consensus documents from major infectious diseases societies were additionally reviewed to supplement. Results: Blood cultures, which are considered the “gold standard” for diagnosis, face important fallouts caused by the limited sensitivity of 50%. Polymerase Chain Reaction assays can identify Candida species at an early stage when compared to blood cultures, demonstrating high specificity that ranges between 91% and 98, due to their high cost, and the limitations regarding only the identification of certain species, their widespread use remains limited. Non-culture serological tests such as mannan, anti-mannan and 1-3-β-D-glucan can detect fungal cell wall components or antibodies directed towards them. These tests have the advantage of being performed directly from blood samples. Reported sensitivity and specificity are 83% and 86% for mannan/anti-mannan, and 73% and 80% for 1-3-β-D-glucan, respectively. They are used for early detection of candidemia in high-risk patients, including immunocompromised individuals. Conclusions: Our report suggests that the traditional “gold standard” for diagnosing invasive candidiasis can be improved by integrating and combining novel biomarkers in the diagnostic pathways, and, thus, potentially reducing the time spent for diagnosing and facilitating early treatment access.