A Rare Modality of Concurrent Cryptococcal and Tubercular Meningitis in a Patient Living With HIV.

Patients with Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/AIDS) and a low CD4 count have decreased humoral and cellular immunity, predisposing them to opportunistic infections. Opportunistic infections are one of the main causes of morbidity and mortality in immunocompromised individuals due to impaired immune systems, particularly in persons living with HIV/AIDS. Common opportunistic infections in patients living with HIV include bacterial infections such as Mycobacterium tuberculosis and Mycobacterium avium complex (MAC); viral infections such as cytomegalovirus (CMV) and herpes simplex virus 1 (HSV-1); fungal infections such as Pneumocystis carinii pneumonia (PCP) and cryptococcal meningitis; and parasitic infections such as cryptosporidiosis and toxoplasmosis. Concurrent infection with cryptococcal and tubercular meningitis in patients with HIV is very rare. Here, we present the case of a 48-year-old male living with HIV who presented with complaints of breathlessness, fever, and weight loss and was evaluated and put on antitubercular medications for pulmonary tuberculosis. However, the presence of a continuous headache led us to investigate further. Upon brain imaging and cerebrospinal fluid evaluation, it was determined to be meningitis due to co-infection with Mycobacterium tuberculosis and Cryptococcus neoformans. The patient was treated with antitubercular therapy along with antifungal therapy. He is under regular follow-up without any further events.

Deciphering Prognostic Indicators in Non-HIV Cryptococcal Meningitis: Constructing and Validating a Predictive Nomogram Model.

Cryptococcal meningitis (CM) is a well-recognized fungal infection, with substantial mortality in HIV-infected individuals. However, the incidence, risk factors, and outcomes in non-HIV adults remain poorly understood. This study aims to investigate the characteristics and prognostic indicators of CM in non-HIV adult patients, integrating a novel predictive model to guide clinical decision-making. A retrospective cohort of 64 non-HIV adult CM patients, including 51 patients from previous studies and 13 from the First Hospital of Shanxi Medical University, was analyzed. We assessed demographic features, underlying diseases, intracranial pressure, cerebrospinal fluid characteristics, and brain imaging. Using the LASSO method, and multivariate logistic regression, we identified significant variables and constructed a Nomogram prediction model. The model's calibration, discrimination, and clinical value were evaluated using the Bootstrap method, calibration curve, C index, goodness-of-fit test, ROC analysis, and DCA analysis. Age, brain imaging showing parenchymal involvement, meningeal and ventricular involvement, and previous use of immunosuppressive agents were identified as significant variables. The Nomogram prediction model displayed satisfactory performance with an AIC value of 72.326, C index of 0.723 (0.592-0.854), and AUC of 0.723, Goodness-of-fit test P=0.995. This study summarizes the clinical and imaging features of adult non-HIV CM, and introduces a tailored Nomogram prediction model to aid in patient management. The identification of predictive factors and the development of the nomogram enhance our understanding and capacity to treat this patient population. The insights derived have potential clinical implications, contributing to personalized care and improved patient outcomes.

Cryptococcal meningitis (CM) is a serious fungal infection that can affect the brain and spinal cord. It is well known to occur in people with HIV, but it can also affect those without HIV, although this is less common. This study focuses on understanding how CM affects non-HIV patients, which is not as well understood as its effects on HIV patients. We analyzed data from 64 non-HIV patients with CM to identify factors that might influence their recovery or lead to poor outcomes, such as severe disability or death. Using advanced statistical methods, we developed a predictive tool called a nomogram. This tool helps doctors estimate the likelihood of a poor outcome in non-HIV CM patients based on specific factors like age, brain imaging results, and the use of certain medications. Our findings suggest that older patients and those with specific brain imaging abnormalities may be at higher risk. On the other hand, patients who have previously used immunosuppressive drugs might have a better prognosis, which is a surprising and new insight. This research is important because it provides new knowledge that could help doctors better manage CM in non-HIV patients, leading to more personalized and effective treatments. The predictive tool we developed could be used in hospitals to improve decision-making and patient care, ultimately improving outcomes for those suffering from this serious condition.

The emerging links between immunosenescence in innate immune system and neurocryptococcosis.

Immunosenescence refers to the age-related progressive decline of immune function contributing to the increased susceptibility to infectious diseases in older people. Neurocryptococcosis, an infectious disease of central nervous system (CNS) caused by Cryptococcus neoformans (C. Neoformans) and C. gattii, has been observed with increased frequency in aged people, as result of the reactivation of a latent infection or community acquisition. These opportunistic microorganisms belonging to kingdom of fungi are capable of surviving and replicating within macrophages. Typically, cryptococcus is expelled by vomocytosis, a non-lytic expulsive mechanism also promoted by interferon (IFN)-I, or by cell lysis. However, whereas in a first phase cryptococcal vomocytosis leads to a latent asymptomatic infection confined to the lung, an enhancement in vomocytosis, promoted by IFN-I overproduction, can be deleterious, leading the fungus to reach the blood stream and invade the CNS. Cryptococcus may not be easy to diagnose in older individuals and, if not timely treated, could be potentially lethal. Therefore, this review aims to elucidate the putative causes of the increased incidence of cryptococcal CNS infection in older people discussing in depth the mechanisms of immunosenscence potentially able to predispose to neurocryptococcosis, laying the foundations for future research. A deepest understanding of this relationship could provide new ways to improve the prevention and recognition of neurocryptococcosis in aged frail people, in order to quickly manage pharmacological interventions and to adopt further preventive measures able to reduce the main risk factors.

Choroid Plexitis and Obstructive Hydrocephalus Secondary to Cryptococcal Meningoencephalitis in an Immunocompetent Individual With Remarkable Imaging Findings: A Case Report.

Cryptococcus is an invasive and opportunistic fungus usually associated with immunocompromised individuals. Invasion of the choroid plexus by Cryptococcus is rare. This report presents the radiologic findings of a previously healthy male with bilateral choroid plexus invasion complicated by obstructive hydrocephalus.

Trends in Clinico-Epidemiological Profile and Outcomes of Patients with HIV-Associated Cryptococcal Meningitis in Shanghai, China, 2013-2023.

The study aimed to analyze changes in the clinical and epidemiological aspects of HIV-associated cryptococcal meningitis (CM) patients and to identify factors influencing their prognosis. Clinical data of patients with HIV-associated CM treated in Shanghai, China between 2013 and 2023 were collected. This study included 279 cases, 2.89% of AIDS patients, showing a yearly decrease in CM prevalence among AIDS patients (p < 0.001). Overall mortality was 10.39% with rates declining from a 2013 peak of 15.38% to 0% in 2023 despite no significant temporal pattern (p = 0.265). Diagnosis took an average of 18 ± 1 days post-symptoms, and admission CD4 counts averaged 29.2 ± 2.5 cells/µL, hinting at a non-significant decline. Frequent symptoms included fever (62.4%), headache (61.6%), fatigue (44.1%), and appetite loss (39.8%), with younger patients more likely to initially show signs of meningeal irritation. Logistic regression analysis underscored the prognostic importance of cerebrospinal fluid (CSF) white blood cell (WBC) count and procalcitonin levels. Over the decade spanning from 2013 to 2023, the incidence and mortality rates of CM among AIDS patients exhibited a downward trend. The average duration from the onset of CM to confirmation of diagnosis remained prolonged. CSF WBC count and procalcitonin levels were associated with unfavorable outcomes.

Efficacy of Liposomal Nystatin in a Rabbit Model of Cryptococcal Meningitis.

Cryptococcal meningitis (CM) causes significant global morbidity and mortality. Current therapeutic strategies rely on deoxycholated or liposomal forms of the polyene amphotericin B. Nystatin is also a polyene with broad-spectrum antimicrobial activity. Treatment with systemic nystatin has been limited by toxicity, which is a consistent challenge with polyene therapeutics. One mechanism to improve the toxicity is usage of a liposomal form of the active agent. Previous data from a murine candidemia model indicated that liposomal nystatin may be an effective antifungal drug formulation. Since the rabbit model of CM is a highly predictive preclinical system for evaluating antifungal therapeutics, we tested the effectiveness of two doses of daily liposomal nystatin, 3 and 8 mg/kg in the rabbit model of CM. Treatment with liposomal nystatin in this model did not reduce the fungal burden in the cerebrospinal fluid. A subsequent clinical trial also did not find activity in a human population. These data indicate that liposomal nystatin in the current form and at the tested dosages is not an effective therapy for CM. The data provide further evidence for the predictive power of the rabbit model of CM as a vital preclinical system for testing novel antifungal therapeutics for CM.

Baseline C-reactive Protein as a Risk Factor for Cryptococcal Meningitis and Death in HIV-associated Cryptococcal Antigenemia With CrAg Titer as an Effect Modifier.

Background: Persons with HIV and cryptococcal antigenemia are at high risk of progression to cryptococcal meningitis or death. Baseline cryptococcal antigen (CrAg) plasma titer ≥1:160 is a known risk factor for poor outcomes, but other risk factors are unknown. In HIV-associated cryptococcal meningitis, baseline serum C-reactive protein (CRP) concentrations are positively associated with increased mortality. We hypothesized that CRP might also be associated with meningitis or death in persons with cryptococcal antigenemia. Methods: We measured plasma CrAg titers and CRP concentrations on cryopreserved serum from prospectively enrolled persons with HIV and cryptococcal antigenemia. Using time-to-event analyses, we compared 24-week meningitis-free survival in persons with normal CRP (<8 mg/L) and elevated CRP (≥8 mg/L). Logistic regression was used to assess how CRP concentration and CrAg titer might interact as covariates. Results: Of the 94 persons with elevated CRP, 19 (20.2%) developed meningitis or death, whereas of the 88 persons with normal CRP, 8 (9.1%) developed meningitis or death (P = .035). Persons with CrAg titer <1:160 and normal CRP had an ∼5% (3/61) event rate, whereas those with CrAg titer <1:160 but elevated CRP had an ∼20% (12/59) event rate. Importantly, we identified a statistically significant interaction effect between CrAg titer and CRP groups, in which elevated CRP increased risk in the low CrAg titer group (odds ratio, 1.54; 95% confidence interval, 1.16-2.04), but this effect was not present in high CrAg titer group (odds ratio, 0.78; 95% confidence interval, .53-1.15). Conclusions: Our findings demonstrate that CrAg titer may modify the direction of effect of CRP with meningitis-free survival; future studies should account for this interaction.

Implementation of single high-dose liposomal amphotericin B based induction therapy for treatment of HIV-associated cryptococcal meningitis in Uganda: a comparative prospective cohort study.

BACKGROUND: In 2022, the World Health Organization (WHO) recommended a single 10mg/kg dose of liposomal amphotericin B in combination with 14 days of flucytosine and fluconazole (AMBITION-cm regimen) for induction therapy of HIV-associated cryptococcal meningitis, based on the results of the multisite AMBITION-cm trial. We evaluated outcomes after real-world implementation of this novel regimen in Uganda. METHODS: We enrolled Ugandan adults with cryptococcal meningitis into an observational cohort receiving the AMBITION-cm regimen with therapeutic lumbar punctures in routine care during 2022-2023. We compared 10-week survival and CSF early fungicidal activity with the outcomes observed in the AMBITION-cm clinical trial conducted at the same sites. RESULTS: During 2022-2023, 179 adults were treated with the AMBITION-cm regimen via routine care and compared to the 171 adults randomized to the AMBITION-cm trial interventional arm in Uganda from 2018-2021. No significant difference in 10-week survival occurred between the observational cohort (68.6%; 95%CI 61.6%-76.3%) and AMBITION-cm trial participants in the intervention arm (71.7%; 95%CI 65.2%-78.8%; absolute risk difference = -3.1%; 95%CI -13.1% to 6.9%; p=.61). Early fungicidal activity did not differ (0.42 vs 0.39 log10CFU/mL/day; p=.80) between groups. Among observational cohort participants discharged alive initially and for whom follow up data were available, the incidence of re-hospitalizations due to persistently elevated intracranial pressure was 2.8% (4/144). CONCLUSION: The AMBITION-cm regimen for cryptococcal meningitis resulted in similar outcomes as observed in the AMBITION-cm clinical trial when implemented in routine care. Intracranial pressure management during hospitalization and awareness after discharge are key components of optimizing outcomes.

Integration of genomic and pharmacokinetic data to predict clinical outcomes in HIV-associated cryptococcal meningitis.

Cryptococcal meningitis causes an estimated 112,000 global deaths per annum. Genomic and phenotypic features of the infecting strain of Cryptococcus spp. have been associated with outcomes from cryptococcal meningitis. Additionally, population-level pharmacokinetic variability is well documented in these patient cohorts. The relative contribution of these factors to clinical outcomes is unknown. Based in Malawi, we conducted a sub-study of the phase 3 Ambition-CM trial (ISRCTN72509687), collecting plasma and cerebrospinal fluid at serial time points during the first 14 days of antifungal therapy. We explored the relative contribution of pathogen genotype, drug resistance phenotype, and pharmacokinetics on clinical outcomes including lumbar opening pressure, pharmacodynamic effect, and mortality. We report remarkable genomic homogeneity among infecting strains of Cryptococcus spp., within and between patients. There was no evidence of acquisition of antifungal resistance in our isolates. Genotypic features of the infecting strain were not consistently associated with adverse or favorable clinical outcomes. However, baseline fungal burden and early fungicidal activity (EFA) were associated with mortality. The strongest predictor of EFA was the level of exposure to amphotericin B. Our analysis suggests the most effective means of improving clinical outcomes from HIV-associated cryptococcal meningitis is to optimize exposure to potent antifungal therapy. IMPORTANCE: HIV-associated cryptococcal meningitis is associated with a high burden of mortality. Research into the different strain types causing this disease has yielded inconsistent findings in terms of which strains are associated with worse clinical outcomes. Our study suggests that the exposure of patients to potent anti-cryptococcal drugs has a more significant impact on clinical outcomes than the strain type of the infecting organism. Future research should focus on optimizing drug exposure, particularly in the context of novel anticryptococcal drugs coming into clinical use.

Lactate dehydrogenase-1 may play a key role in the brain energy disturbance caused by cryptococcal meningitis.

BACKGROUND: Cryptococcal meningitis (CM) may affect the conversion of lactate to pyruvate in the brain, resulting in abnormal levels of adenosine triphosphate (ATP) throughout the brain. Lactate conversion to pyruvate is mainly caused by lactic dehydrogenase 1 (LDH1), which is composed of four LDHB subunits. However, the underlying mechanism of LDH1 in CM remains unclear. METHODS: Cerebrospinal fluid (CSF) from 17 patients was collected, including eight patients with non-infectious diseases of the central nervous system and nine patients with CM. Based on clinical data and laboratory reports, data regarding intracranial pressure, CSF white cell counts, lactate dehydrogenase (LDH), adenosine deaminase, glucose, protein, and chloridion were collected. Meanwhile, LDH1, LDH5, lactate, pyruvate, and ATP levels were detected in CSF. Whereafter, the levels of lactate, pyruvate, ATP, and the amplitude and frequency of action potentials in the neurons with low expression of LDHB were explored. RESULTS: Intracranial pressure and white cell count in CSF were significantly increased in patients with CM. In patients with CM, the LDH1, pyruvate, and ATP levels in the CSF were significantly decreased, and the levels of lactate were found to be increased. Furthermore, pyruvate and ATP levels were decreased, while lactate was increased in the neurons with low expression of LDHB. The amplitude and frequency of APs in the neurons with low expression of LDHB were significantly decreased. CONCLUSION: Reduced levels of LDH1 in the brain of patients with CM may lead to increased lactate levels, decreased pyruvate and ATP levels, and negatively affect neuronal activity.

CSF Cytokines and Chemokines Involved in Cytotoxic Cell Function and Risk of Acute 14-Day Mortality in Persons with Advanced HIV and Cryptococcal Meningitis.

BACKGROUND: Despite availability of HIV treatment globally, cryptococcal meningitis continues to cause considerable morbidity and mortality. The role of the immune response in acute mortality remains unclear. METHODS: To investigate the immune environment in the central nervous system, cerebrospinal fluid (CSF) from 337 Ugandans with advanced HIV and first-episode cryptococcal meningitis was collected at time of hospitalization. Participants were treated with standard of care amphotericin-B and fluconazole. Cytokines and chemokines in the CSF were quantified and compared by 14-day survival, stratification by quartiles, and logistical regression to determine association with acute mortality. RESULTS: 84 (24.9%) of the participants died by day 14 of hospitalization. Persons who survived to day 14 had higher levels of proinflammatory macrophage inflammatory protein (MIP)-3ß and interferon (IFN)-ß and cytotoxicity-associated Granzyme-B and inflammatory protein (IP)-10 compared to those who died (P<.05 for each). Logistical regression analysis revealed that per two-fold increase in proinflammatory IL-6, IL-1α, MIP-1ß, MIP-3ß, and IFN-ß and cytotoxicity-associated IL-12, TNF-α, Granzyme-B, and IP-10 CSF concentrations, the risk of acute 14-day mortality decreased. Similar biomarkers were implicated when stratified by quartiles and further identified that lower concentrations of anti-inflammatory IL-10 and IL-13 as associated with 14-day mortality (P<.05 for each). CONCLUSION: Proinflammatory and cytotoxicity-associated cytokine and chemokine responses in the CSF decrease the risk of acute 14-day mortality. These data suggest that a cytotoxic immune environment in the CSF could potentially improve acute survival. Further research on cytotoxic cells is crucial to improve understanding of innate and adaptive immune responses in cryptococcal meningitis.

Mid-Upper Arm Circumference Is a Strong Predictor of Mortality Among Ugandan Adults With HIV-Associated Cryptococcal Meningitis: A Prospective Cohort Study.

Background: Mortality among adults diagnosed with HIV-associated cryptococcal meningitis remains high (24%-40%). We hypothesized that nutritional state, as measured by mid-upper arm circumference (MUAC), is a potentially modifiable risk factor for mortality. Methods: Ugandan adults hospitalized with HIV-associated cryptococcal meningitis had MUAC measurements performed at baseline. We compared MUAC measurements with baseline clinical and demographic variables and investigated associations with survival using Cox regression. Results: Of 433 participants enrolled, 41% were female, the median CD4 T-cell count (interquartile range [IQR]) was 15 (6-41) cells/µL, and 37% were antiretroviral therapy naïve. The median MUAC (IQR) was 24 (22-26) cm, the median weight (IQR) was 53 (50-60) kg, and MUAC correlated with weight (Pearson r = 0.6; P < .001). Overall, 46% (200/433) died during the 18-week follow-up. Participants in the lowest MUAC quartile (≤22 cm) had the highest mortality: 39% (46/118) at 2 weeks and 62% (73/118) at 18 weeks. A baseline MUAC ≤22 cm was associated with an 82% increased risk of 18-week mortality as compared with participants with an MUAC >22 cm (unadjusted hazard ratio, 1.82; 95% CI, 1.36-2.42; P < .001). Following adjustment for antiretroviral therapy status, CD4 count, hemoglobin, amphotericin dose, and tuberculosis status, the adjusted hazard ratio was 1.84 (95% CI, 1.27-2.65; P < .001). As a continuous variable, 18-week mortality was reduced by 10% for every 1-cm increase in MUAC. CSF Th17 immune responses were positively associated with MUAC quartile. Conclusions: MUAC measurement is a simple bedside tool that can identify adults with HIV-associated cryptococcal meningitis at high risk for mortality for whom an enhanced bundle of care, including nutritional supplementation, should be further investigated.

Characteristics of HIV-associated cryptococcal meningitis in a tertiary Chilean hospital: An observational retrospective study.

BACKGROUND: Central nervous system opportunistic infections can be the first presentation of an HIV infection. Our aim is to describe clinical and laboratory characteristics of HIV-associated Cryptococcal Meningitis (CM), in-hospital outcomes and analyze associations of these parameters with adverse outcomes. METHODS: Observational study of local cohort of HIV-associated cryptococcal meningitis in a high complexity tertiary urban hospital in Santiago, Chile. Descriptive analysis through chart review of all episodes of HIV-associated CM in adults, from 1995 to 2019. Inclusion criteria were confirmed CM with cerebrospinal fluid culture or India ink in the appropriate clinical context and HIV diagnosis. We selected relevant variables that have been described as predictors of adverse outcomes in the literature and explore associations in our cohort. RESULTS: There were 37 HIV associated CM cases, occurring from 2000 to 2019. Majority were men (86 %) with a median age of 35 years. CM was the first HIV manifestation in 32 %. Opening pressure was measured in 10 % of patients at admission. Most CSF parameters were mildly altered, and two patients presented with completely normal CSF findings. Most patients -94,4 %- suffered adverse events secondary to antifungal therapy. Despite of recommendations against their use, steroids were frequently prescribed. Mortality was 18,9 %, and was associated with older age, and more days of headache prior to admission. CONCLUSIONS: CM clinical presentation and CSF characteristics are variable at presentation, which can lead to delayed diagnosis. Inappropriate use of corticosteroids, antifungal toxicity and suboptimal management of elevated intracranial pressure are key aspects to improve.

Epidemiology of cryptococcal meningitis and fluconazole heteroresistance in Cryptococcus neoformans isolates from a teaching hospital in southwestern China.

Cryptococcal meningitis (CM), a common and serious opportunistic infection mostly caused by Cryptococcus neoformans, is primarily treated with fluconazole. Nevertheless, Cryptococcus neoformans strains that undergo repeated exposure to azoles can gradually acquire heteroresistance to fluconazole. The management of this specific CM infection poses a substantial challenge. Determining a globally accepted definition for fluconazole heteroresistance and developing effective and prompt methods for identifying heteroresistance is of utmost importance. We collected data on the clinical and epidemiological characteristics of patients diagnosed with CM. All the available Cryptococcus neoformans strains isolated from these patients were collected and subjected to antifungal susceptibility testing and evaluation of fluconazole heteroresistance. AIDS was present in 40.5% of the patients, whereas 24.1% did not have any underlying diseases. Patients with chronic diseases or impaired immune systems are susceptible to infection by Cryptococcus neoformans, a fungus that frequently (39.6%, 19/48) shows heteroresistance to fluconazole, as confirmed by population analysis profile (PAP).IMPORTANCEFluconazole heteroresistance poses a significant threat to the efficacy of fluconazole in treating cryptococcal meningitis (CM). Unfortunately, the standard broth microdilution method often misses the subtle percentages of subpopulations exhibiting heteroresistance. While the population analysis profile (PAP) method is esteemed as the gold standard, its time-consuming and labor-intensive nature makes it impractical for routine clinical use. In contrast, the Kirby-Bauer (KB) disk diffusion method offers a simple and effective screening solution. Our study highlights the value of KB over PAP and minimum inhibitory concentration (MIC) by demonstrating that when adjusting the inoculum concentration to 1.0 McFarland and subjecting samples to a 72-hour incubation period at 35°C, the KB method closely mirrors the outcomes of the PAP approach in detecting fluconazole heteroresistance. This optimization of the KB method not only enhances assay efficiency but also provides a blueprint for developing a timely and effective strategy for identifying heteroresistance.

Cryptococcal Meningitis in an Immunocompetent Patient With Underlying Risk Factors.

Cryptococcal meningitis, a severe fungal infection of the central nervous system, is usually found in immunocompromised patients, especially those with human immunodeficiency virus/acquired immunodeficiency syndrome. Its occurrence in immunocompetent individuals is rare and the presentation can be nonspecific. We present a case of cryptococcal meningitis in a young, immunocompetent male with a known history of intravenous drug abuse who was also found to have hepatitis C during admission. Induction therapy with amphotericin B and flucytosine was completed for 14 days. This shorter duration was considered as he had a good clinical response with rapid improvement in mental status and intracranial pressure with an extraventricular drain and negative repeat cerebrospinal fluid (CSF) culture. However, during the consolidation phase with fluconazole, the patient developed new neurologic symptoms and the induction phase had to be re-initiated for a total of 28 days. The patient likewise required the re-placement of an extraventricular drain and the creation of a ventriculoperitoneal shunt due to persistent CSF accumulation and increased intracranial pressure. He was eventually discharged on fluconazole for a planned consolidation phase of eight weeks, followed by a prolonged maintenance phase, but the patient was lost to follow-up.

Cryptococcosis-a systematic review to inform the World Health Organization Fungal Priority Pathogens List.

Cryptococcosis causes a high burden of disease worldwide. This systematic review summarizes the literature on Cryptococcus neoformans and C. gattii infections to inform the World Health Organization's first Fungal Priority Pathogen List. PubMed and Web of Science were used to identify studies reporting on annual incidence, mortality, morbidity, antifungal resistance, preventability, and distribution/emergence in the past 10 years. Mortality rates due to C. neoformans were 41%-61%. Complications included acute renal impairment, raised intracranial pressure needing shunts, and blindness. There was moderate evidence of reduced susceptibility (MIC range 16-32 mg/l) of C. neoformans to fluconazole, itraconazole, ketoconazole, voriconazole, and amphotericin B. Cryptococcus gattii infections comprised 11%-33% of all cases of invasive cryptococcosis globally. The mortality rates were 10%-23% for central nervous system (CNS) and pulmonary infections, and ∼43% for bloodstream infections. Complications described included neurological sequelae (17%-27% in C. gattii infections) and immune reconstitution inflammatory syndrome. MICs were generally low for amphotericin B (MICs: 0.25-0.5 mg/l), 5-flucytosine (MIC range: 0.5-2 mg/l), itraconazole, posaconazole, and voriconazole (MIC range: 0.06-0.5 mg/l). There is a need for increased surveillance of disease phenotype and outcome, long-term disability, and drug susceptibility to inform robust estimates of disease burden.

Infectious Diseases Physician Management of Cryptococcal Meningitis in North America-Is Single High-Dose Liposomal Amphotericin B Being Used?

Background: Several recent randomized trials have been conducted in resource-limited settings for cryptococcal meningitis that have rapidly innovated international guidelines. The 2010 Infectious Diseases Society of America (IDSA) cryptococcal meningitis guideline has not been updated with recent trials. The 2022 AMBITION-cm trial found that a single 10-mg/kg dose of liposomal amphotericin B plus daily flucytosine and fluconazole for 2 weeks was noninferior to 1 week of amphotericin B deoxycholate with flucytosine. It is unknown whether physicians in high-resource settings are using this regimen or more traditional regimens. Methods: We developed an electronic survey in June 2023 to better understand whether physician members of the IDSA Emerging Infections Network (EIN) and Mycoses Study Group Education and Research Consortium (MSG-ERC) had used the AMBITION-cm induction regimen, would use the regimen in hypothetical clinical scenarios, and what perceived barriers to use existed. Results: A total of 242 of 561 (43%) physicians responded to the survey, of whom 205 provided care for persons with cryptococcal meningitis in the last year. Overall, 29 (14%) had used the AMBITION-cm regimen, and 176 (86%) had not. In various hypothetical clinical scenarios, only ∼10% of 209 respondents selected the AMBITION-cm regimen as preferred. Perceived barriers to uptake included the applicability of trials performed in low-resource settings to high-resource settings, that the regimen is not recommended in the 2010 IDSA guidelines, and the applicability to persons without HIV. Conclusions: Most respondents had not used the single-dose liposomal amphotericin B regimen, but the regimen is being used. Further study of this regimen in other patient populations and settings is necessary.

Lived experience of people with cryptococcal meningitis: A qualitative study.

Background: The high burden of cryptococcal meningitis (CM) among people living with HIV persists despite widespread access to antiretroviral therapy. Efforts to prevent CM among people living with HIV could be hindered by a limited understanding of their lived experiences of CM and its diagnosis. Objectives: To explore and describe the experiences of people diagnosed with HIV-associated CM in routine care. Two public healthcare facilities in Johannesburg, South Africa. Method: This was a qualitative-methods exploratory, descriptive, phenomenological study. We conducted semi-structured, individual in-depth interviews with nine purposively sampled participants (comprising 5 men and 4 women). Data were analysed using the Moustakas phenomenological approach. Results: Five themes and several sub-themes emerged from the data. Participants described their experiences of being diagnosed, which were marked by intense headaches. Diagnosis of CM led to reduced quality of life, fear of death, and loss of income. Participants described their CM treatment experience and health-seeking behaviour including self-medication, seeking help from traditional healers and general practitioners and utilising public health facilities as a last resort. Barriers to care included negative healthcare workers' attitudes, unhealthy lifestyles, and poor knowledge of CM. Conclusion: People with HIV-associated CM face negative impacts prior to and after diagnosis. These patients struggled to access timely quality healthcare. Patients starting or restarting antiretroviral therapy, and thus at risk for CM, should receive CM education as part of HIV counselling.

Inbred Mouse Models in Cryptococcus neoformans Research.

Animal models are frequently used as surrogates to understand human disease. In the fungal pathogen Cryptococcus species complex, several variations of a mouse model of disease were developed that recapitulate different aspects of human disease. These mouse models have been implemented using various inbred and outbred mouse backgrounds, many of which have genetic differences that can influence host response and disease outcome. In this review, we will discuss the most commonly used inbred mouse backgrounds in C. neoformans infection models.

Comparison of early fungicidal activity and mortality between daily liposomal amphotericin B and daily amphotericin B deoxycholate among patients with HIV-associated cryptococcal meningitis.

BACKGROUND: Limited data exist on the antifungal activity of daily liposomal amphotericin B with flucytosine induction regimens for cryptococcal meningitis, which are recommended in high-income countries. Liposomal amphotericin B monotherapy at 3 mg/kg previously failed to meet non-inferiority criteria compared to amphotericin B deoxycholate in its registrational clinical trial. We aimed to compare the quantitative antifungal activity and mortality between daily amphotericin B deoxycholate and daily liposomal amphotericin among persons with HIV-related cryptococcal meningitis receiving adjunctive flucytosine 100 mg/kg/day. METHODS: We analyzed data from three clinical studies involving participants with HIV-associated cryptococcal meningitis receiving either daily liposomal amphotericin B at 3 mg/kg/day with flucytosine (N = 94) or amphotericin B deoxycholate at 0.7-1.0 mg/kg/day with flucytosine (N = 404) as induction therapy. We compared participant baseline characteristics, CSF early fungicidal activity (EFA), and 10-week mortality. RESULTS: We included 498 participants in this analysis, of whom 201 had available EFA data (N = 46 liposomal amphotericin; N = 155 amphotericin deoxycholate). Overall, there is no statistical evidence that the antifungal activity of liposomal amphotericin B (mean EFA = 0.495 log10 CFU/mL/day; 95%CI, 0.355-0.634) differ from amphotericin B deoxycholate (mean EFA = 0.402 log10 CFU/mL; 95%CI, 0.360-0.445) (P = 0.13). Mortality at 10 weeks trended lower for liposomal amphotericin (28.2%) vs amphotericin B deoxycholate (34.6%) but was not statistically different when adjusting for baseline characteristics (adjusted Hazard Ratio = 0.74; 95%CI, 0.44-1.25; P = 0.26). CONCLUSIONS: Daily liposomal amphotericin B induction demonstrated a similar rate of CSF fungal clearance and 10-week mortality as amphotericin B deoxycholate when combined with flucytosine for the treatment of HIV-associated cryptococcal meningitis.