Microglia are not protective against cryptococcal meningitis.

Microglia provide protection against a range of brain infections including bacteria, viruses and parasites, but how these glial cells respond to fungal brain infections is poorly understood. We investigated the role of microglia in the context of cryptococcal meningitis, the most common cause of fungal meningitis in humans. Using a series of transgenic- and chemical-based microglia depletion methods we found that, contrary to their protective role during other infections, loss of microglia did not affect control of Cryptococcus neoformans brain infection which was replicated with several fungal strains. At early time points post-infection, we found that microglia depletion lowered fungal brain burdens, which was related to intracellular residence of C. neoformans within microglia. Further examination of extracellular and intracellular fungal populations revealed that C. neoformans residing in microglia were protected from copper starvation, whereas extracellular yeast upregulated copper transporter CTR4. However, the degree of copper starvation did not equate to fungal survival or abundance of metals within different intracellular niches. Taken together, these data show how tissue-resident myeloid cells may influence fungal phenotype in the brain but do not provide protection against this infection, and instead may act as an early infection reservoir.

Retrospective Assessment of a National Reflex Cryptococcal Antigen Screening Program in South Africa Through Interlaboratory Comparison of Lateral Flow Assay Results.

OBJECTIVE: Reflex cryptococcal antigen (CrAg) screening of blood specimens with a CD4 count of <100 cells/µL was performed at 45 South African CD4 laboratories using a lateral flow assay (LFA). Our objective was to evaluate the reliability of routine LFA results through comparative interlaboratory testing. METHODS: All CrAg-positive and a selected number of CrAg-negative samples from the CD4 laboratories were retested at paired microbiology laboratories using the same LFA. Samples with discordant results were tested at a reference laboratory, using the LFA (with CrAg titers). RESULTS: During interlaboratory testing, 12,502 samples were retested, with 93 (0.7%) discordant results and a between-laboratory agreement of 99.3% (Cohen's kappa, 0.98). The proportion of retested samples with discordant results ranged from 0.17% to 5.31% per laboratory pair (median 0.28%), with 3 reporting >3% of results as discordant. CONCLUSION: Routine CrAg screening results were reliable, with <1% of samples having discordant results, mainly due to interpretation and transcription errors.

Evaluation of the initial 12 months of a routine cryptococcal antigen screening program in reduction of HIV-associated cryptococcal meningitis in Uganda.

BACKGROUND: Asymptomatic Cryptococcal Antigenemia (CrAg) patients develop meningitis within a month of testing positive. Pre-emptive antifungal therapy can prevent progression to Cryptococcal meningitis (CM). In April 2016, a national CrAg screening program was initiated in 206 high-volume health facilities that provide antiretroviral therapy in Uganda. We report the evaluation of the CrAg screening cascade focusing on linkage to care, fluconazole therapy for 10 weeks and 6 months follow up, and ART initiation in a subset of facilities. METHODS: We conducted a retrospective, cross-sectional survey of patients with CD4 < 100 at seven urban and seven rural facilities after 1 year of program implementation. We quantified the number of patients who transitioned through the steps of the CrAg screening cascade over six-months follow-up. We defined cascade completion as a pre-emptive fluconazole prescription for the first 10 weeks. We conducted semi-structured interviews with lab personnel and clinic staff to assess functionality of the CrAg screening program. Data was collected using REDCap. RESULTS: We evaluated 359 patient records between April 2016 to March 2017; the majority (358/359, 99.7%) were from government owned health facilities and just over half (193/359, 53.8%) had a median baseline CD4 cell count of < 50 cell/µL. Overall, CrAg screening had been performed in 255/359 (71.0, 95% CI, 66.0-75.7) of patients' records reviewed, with a higher proportion among urban facilities (170/209 (81.3, 95% CI, 75.4-86.4)) than rural facilities (85/150 (56.7, 95% CI, 48.3-64.7)). Among those who were CrAg screened, 56/255 (22.0, 95% CI, 17.0-27.5%) had cryptococcal antigenemia, of whom 47/56 (83.9, 95% CI, 71.7-92.4%) were initiated on pre-emptive therapy with fluconazole and 8/47 (17.0, 95% CI, 7.6-30.8%) of these were still receiving antifungal therapy at 6 months follow up. At least one CNS symptom was present in 70% (39/56) of those with antigenemia. In patients who had started ART, almost 40% initiated ART prior to CrAg screening. Inadequacy of equipment/supplies was reported by 15/26 (58%) of personnel as a program barrier, while 13/26 (50%) reported a need for training about CM and CrAg screening. CONCLUSION: There was a critical gap in the follow-up of patients after initiation on fluconazole therapy. ART had been initiated in almost 40% of patients prior to CrAg screening.. Higher antigenemia patients presenting with CNS symptoms could be related to late presentation. There is need to address these gaps after a more thorough evaluation.

Cost-effectiveness of single-dose AmBisome pre-emptive treatment for the prevention of cryptococcal meningitis in African low and middle-income countries.

Cryptococcal antigen (CrAg) screening is recommended for patients with advanced HIV to reduce AIDS-related mortality. For asymptomatic CrAg-positive persons, fluconazole pre-emptive therapy is standard, despite a ∼25% failure rate. Single-dose liposomal amphotericin B (AmBisome) is non-inferior to standard treatment for cryptococcal meningitis. We evaluate the threshold of efficacy necessary for AmBisome + fluconazole to be cost-effective as pre-emptive therapy for CrAg-positive persons.We created a decision analytic model to evaluate CrAg screening and treatment in HIV-infected persons with CD4 < 100 cells/µL. Costs were estimated for screening, pre-emptive therapy, and hospitalization for an example low-income country (Uganda) and middle-income country (South Africa). We used a discounted price range of AmBisome® at ${\$}$16.25 to ${\$}$40 per 50 mg vial for both Uganda and South Africa. We estimated AmBisome efficacy from 75 to 95%. Parameter assumptions were based on prospective CrAg screening studies and clinical trials in Africa. Disability adjusted life years (DALYs) were calculated using the age-specific life expectancy in Uganda, per WHO Global Health Observatory data. We modeled the theoretical efficacy of adjunctive AmBisome to determine cost per DALY averted.In South Africa, at ${\$}$16.25 per vial cost and a minimum efficacy of 85%, adjunctive AmBisome is cost-saving compared to fluconazole monotherapy. Compared to fluconazole pre-emptive therapy in Uganda, AmBisome + fluconazole would cost ${\$}$475, ${\$}$220, or ${\$}$136 per DALY averted if meningitis-free survival efficacy was 80, 85, or 90% at ${\$}$24 per vial cost.Investing in AmBisome may be cost-effective in low-income settings compared to using fluconazole pre-emptive therapy alone, if efficacy is 85% or greater. AmBisome pre-emptive therapy appears more cost-efficient in middle-income settings where hospitalization costs for meningitis, and GDP per capita are higher. LAY SUMMARY: We evaluate the efficacy necessary for AmBisome + fluconazole to be cost-effective to prevent cryptococcal meningitis. We found that if AmBisome pre-emptive therapy has an efficacy of 85% or greater, it is likely to be cost-effective in low-income settings.

Cost-Effectiveness Analysis of the Implementation of Cryptococcal Antigen Lateral Flow Assay for the Diagnosis of Cryptococcal Meningitis in Symptomatic People Living With Human Immunodeficiency Virus in Brazil.

OBJECTIVES: Cryptococcal meningitis constitutes a significant source of mortality in the developing world. Annually, approximately 625 000 deaths occur worldwide among patients with human immunodeficiency virus (HIV) infection. This study aims to assess the cost-effectiveness of implementing cryptococcal antigen lateral flow assay (CRAG-LFA) screening in Brazil compared with the current practice. METHODS: An economic evaluation using a Monte Carlo microsimulation was conducted, considering the perspective of the Brazilian Public Health System, to calculate the cost-effectiveness of 4 diagnosis tests: (1) CRAG-LFA, (2) the cryptococcal antigen latex agglutination (CRAG-LA) test, (3) India ink, and (4) nontracking as a baseline. The time horizon comprised 1 year for the intervention and 5 years for the budgetary impact analysis. Two primary effectiveness outcomes were considered: years of life and quality-adjusted life-years. RESULTS: CRAG-LFA has extended dominance vis à vis CRAG-LA and India ink. CRAG-LFA would cost $418.46 more than CRAG-LA for the treatment of each symptomatic patient living with HIV, with an incremental cost effectiveness ratio of $2478.75/quality-adjusted life year. The budgetary impact analysis estimated that the incorporation of CRAG-LFA would have an additional cost of $1 959 236.50 in 5 years. CONCLUSIONS: These findings suggest that, for patients living with HIV in the Brazilian Public Health System, the adoption of CRAG-LFA screening is cost-effective compared with the use of CRAG-LA and India ink. It represents an opportunity to prevent cryptococcal meningitis and its mortality in Brazil.

Laboratory Reflex and Clinic-Based Point-of-Care Cryptococcal Antigen Screening for Preventing Meningitis and Mortality Among People Living With HIV.

INTRODUCTION: Cryptococcosis remains a leading cause of meningitis and mortality among people living with HIV (PLHIV) worldwide. We sought to evaluate laboratory-based cryptococcal antigen (CrAg) reflex testing and a clinic-based point-of-care (POC) CrAg screening intervention for preventing meningitis and mortality among PLHIV in South Africa. METHODS: We conducted a prospective pre-post intervention study of adults presenting for HIV testing in Umlazi township, South Africa, over a 6-year period (2013-2019). Participants were enrolled during 3 phases of CrAg testing: CrAg testing ordered by a clinician (clinician-directed testing, 2013-2015); routine laboratory-based CrAg reflex testing for blood samples with CD4 ≤100 cells/mm3 (laboratory reflex testing, 2015-2017); and a clinic-based intervention with POC CD4 testing and POC CrAg testing for PLHIV with CD4 ≤200 cells/mm3 with continued standard-of-care routine laboratory reflex testing among those with CD4 ≤100 cells/mm3 (clinic-based testing, 2017-2019). The laboratory and clinical teams performed serum CrAg by enzyme immunoassay and lateral flow assay (Immy Diagnostics, Norman, OK). We followed up participants for up to 14 months to compare associations between baseline CrAg positivity, antiretroviral therapy and fluconazole treatment initiation, and outcomes of cryptococcal meningitis, hospitalization, and mortality. RESULTS: Three thousand one hundred five (39.4%) of 7877 people screened were HIV-positive, of whom 908 had CD4 ≤200 cells/mm3 and were included in the analyses. Laboratory reflex and clinic-based testing increased CrAg screening (P < 0.001) and diagnosis of CrAg-positive PLHIV (P = 0.011). When compared with clinician-directed testing, clinic-based CrAg testing showed an increase in the number of PLHIV diagnosed with cryptococcal meningitis (4.5% vs. 1.5%; P = 0.059), initiation of fluconazole preemptive therapy (7.2% vs. 2.5%; P = 0.010), and initiation of antiretroviral therapy (96.8% vs. 91.3%; P = 0.012). Comparing clinic-based testing with laboratory reflex testing, there was no significant difference in the cumulative incidence of cryptococcal meningitis (4.5% vs. 4.1%; P = 0.836) or mortality (8.1% vs. 9.9%; P = 0.557). CONCLUSIONS: Laboratory reflex and clinic-based CrAg testing facilitated the diagnosis of HIV-associated cryptococcosis and fluconazole initiation but did not reduce cryptococcal meningitis or mortality. In this nonrandomized cohort, clinical outcomes were similar between laboratory reflex testing and clinic-based POC CrAg testing.

Benefits of enhanced infection prophylaxis at antiretroviral therapy initiation by cryptococcal antigen status.

OBJECTIVES: To assess baseline prevalence of cryptococcal antigen (CrAg) positivity; and its contribution to reductions in all-cause mortality, deaths from cryptococcus and unknown causes, and new cryptococcal disease in the REALITY trial. DESIGN: Retrospective CrAg testing of baseline and week-4 plasma samples in all 1805 African adults/children with CD4+ cell count less than 100 cells/µl starting antiretroviral therapy who were randomized to receive 12-week enhanced-prophylaxis (fluconazole 100 mg/day, azithromycin, isoniazid, cotrimoxazole) vs. standard-prophylaxis (cotrimoxazole). METHODS: Proportional hazards models were used to estimate the relative impact of enhanced-prophylaxis vs. standard-cotrimoxazole on all, cryptococcal and unknown deaths, and new cryptococcal disease, through 24 weeks, by baseline CrAg positivity. RESULTS: Excluding 24 (1.4%) participants with active/prior cryptococcal disease at enrolment (all treated for cryptococcal disease), 133/1781 (7.5%) participants were CrAg-positive. By 24 weeks, 105 standard-cotrimoxazole vs. 78 enhanced-prophylaxis participants died. Of nine standard-cotrimoxazole and three enhanced-prophylaxis cryptococcal deaths, seven and two, respectively, were CrAg-positive at baseline. Among deaths of unknown cause, only 1/46 standard-cotrimoxazole and 1/28 enhanced-prophylaxis were CrAg-positive at baseline. There was no evidence that relative reductions in new cryptococcal disease associated with enhanced-prophylaxis varied between baseline CrAg-positives [hazard-ratio = 0.36 (95% confidence interval 0.13-0.98), incidence 19.5 vs. 56.5/100 person-years] and CrAg-negatives [hazard-ratio = 0.33 (0.03-3.14), incidence 0.3 vs. 0.9/100 person-years; Pheterogeneity = 0.95]; nor for all deaths, cryptococcal deaths or unknown deaths (Pheterogeneity > 0.3). CONCLUSION: Relative reductions in cryptococcal disease/death did not depend on CrAg status. Deaths of unknown cause were unlikely to be cryptococcus-related; plausibly azithromycin contributed to their reduction. Findings support including 100 mg fluconazole in an enhanced-prophylaxis package at antiretroviral therapy initiation where CrAg screening is unavailable/impractical.

An Antivirulence Approach for Preventing Cryptococcus neoformans from Crossing the Blood-Brain Barrier via Novel Natural Product Inhibitors of a Fungal Metalloprotease.

Cryptococcus neoformans (Cn) is the leading cause of fungal meningitis, a deadly disease with limited therapeutic options. Dissemination to the central nervous system hinges on the ability of Cn to breach the blood-brain barrier (BBB) and is considered an attribute of Cn virulence. Targeting virulence instead of growth for antifungal drug development has not been fully exploited despite the benefits of this approach. Mpr1 is a secreted fungal metalloprotease not required for fungal growth, but rather, it functions as a virulence factor by facilitating Cn migration across the BBB. This central role for Mpr1, its extracellular location, and lack of expression in mammalian cells make Mpr1 a high-value target for an antivirulence approach aimed at developing therapeutics for cryptococcal meningitis. To test this notion, we devised a large-scale screen to identify compounds that prohibited Cn from crossing the BBB by selectively blocking Mpr1 proteolytic activity, without inhibiting the growth of Cn A phytochemical natural product-derived library was screened to identify new molecular scaffolds of prototypes unique to a Cn microecosystem. Of the 240 pure natural products examined, 3 lead compounds, abietic acid, diosgenin, and lupinine inhibited Mpr1 proteolytic activity with 50% inhibitory concentration (IC50) values of <10 µM, displayed little to no mammalian cell toxicity, and did not affect Cn growth. Notably, the lead compounds blocked Cn from crossing the BBB, without damaging the barrier integrity, suggesting the bioactive molecules had no off-target effects. We propose that these new drug scaffolds are promising candidates for the development of antivirulence therapy against cryptococcal meningitis.IMPORTANCE Fungal infections like cryptococcal meningitis are difficult to resolve because of the limited therapies available. The small arsenal of antifungal drugs reflect the difficulty in finding available targets in fungi because like mammalian cells, fungi are eukaryotes. The limited efficacy, toxicity, and rising resistance of antifungals contribute to the high morbidity and mortality of fungal infections and further underscore the dire but unmet need for new antifungal drugs. The traditional approach in antifungal drug development has been to target fungal growth, but an attractive alternative is to target mechanisms of pathogenesis. An important attribute of Cryptococcus neoformans (Cn) pathogenesis is its ability to enter the central nervous system. Here, we describe a large-scale screen that identified three natural products that prevented Cn from crossing the blood-brain barrier by inhibiting the virulence factor Mpr1 without affecting the growth of Cn We propose that compounds identified here could be further developed as antivirulence therapy that would be administered preemptively or serve as a prophylactic in patients at high risk for developing cryptococcal meningitis.

Tackling cryptococcal meningitis in Nigeria, one-step at a time; the impact of training.

BACKGROUND: Nigeria is estimated to have 25,000 cases of cryptococcal antigenemia (CrAg) annually. CrAg screening with pre-emptive fluconazole treatment is recommended but not yet implemented in Nigeria. Trainings were conducted to improve health-care provider (HCP) awareness and clinical skills in the management and prevention of cryptococcal meningitis (CM). METHODS: HCPs providing care for people living with HIV were targeted for training at 13 sites from April to November 2018 Course content was adapted from CDC Cryptococcal Screening Program Training Manual and LIFE-website. "Hands-on" training on CrAg testing and lumbar puncture was included. A 14-point pre and post-test assessment instrument was designed to capture the impact of the training and focus group discussions (FGDs) were conducted. RESULTS: A total of 761 HCPs were trained. 519 HCPs completed the pre-test evaluation while 470 (90.6%) took part in the post-test evaluation. Post-training, HCPs were significantly more likely to respond correctly to all 14 assessment items, with the mean percentage score rising to 91.0% from a pre-training value of 60.0%. FGDs revealed that many of the HCPs were not aware of the CrAg screening and pre-emptive treatment recommendations in Nigerian guidelines, and reported not having seen or managed a case of CM. Also, they highlighted challenges with routine CrAg screening due to a lack of access to CD4 testing, CrAg test kits, antifungal drugs, as well as the need for similar trainings across all tiers of care in Nigeria. CONCLUSION: Training significantly improved HCPs' understanding of Nigerian policy on CrAg screening, CM diagnosis and best management practices. This training could be included in routine capacity building efforts for HCPs involved in HIV care in Nigeria.

The prevalence of cryptococcal antigen (CrAg) and benefits of pre-emptive antifungal treatment among HIV-infected persons with CD4+ T-cell counts < 200 cells/µL: evidence based on a meta-analysis.

BACKGROUND: Current WHO guidelines (2018) recommend screening for cryptococcal antigen (CrAg) in HIV-infected persons with CD4+ T cell counts< 100 cells/µL, followed by pre-emptive antifungal therapy among CrAg positive (CrAg+) persons, to prevent cryptococcal meningitis related deaths. This strategy may also be considered for those persons with a CD4+ T cell count of < 200 cells/uL according the WHO guidelines. However, there is sparse evidence in the literature supporting CrAg screening and pre-emptive antifungal therapy in those HIV-infected persons with this CD4+ T cell counts< 200 cells/µL. METHOD: We conducted a meta-analysis using data extracted from randomized controlled studies (RCTs) and cohort studies found in a search of Pubmed, Web of Science, the Cochrane Library and the EMBASE/MEDLINE database. RESULTS: The pooled prevalence of CrAg positivity in HIV-infected persons with CD4+ T cell counts< 200 cells/µL was 5% (95%CI: 2-7). The incidence of CM in CrAg+ persons was 3% (95%CI: 1-6). Among those CrAg+ persons who did not receive pre-emptive treatment, or those who received placebo, the incidence of CM was 5% (95%CI: 2-9), whereas the incidence of CM among those who received pre-emptive antifungal therapy was 3% (95%CI: 1-6), which is a statistically significant reduction in incidence of 40% (RR: 7.64, 95%CI: 2.96-19.73, p < 0.00001). As for persons with CD4+ T cell counts between 101 ~ 200 cells/µL, the risk ratio for the incidence of CM among those receiving placebo or no intervention was 1.15, compared to those receiving antifungal treatment (95%CI: 0.16-8.13). CONCLUSIONS: In our meta-analysis the incidence of CM was significantly reduced by pre-emptive antifungal therapy in CrAg+ HIV-infected persons with CD4 <  200 cells/µL. However, more specific observational data in persons with CD4+ T cell counts between 101 ~ 200 cells/µL are required in order to emphasize specific benefit of CrAg screening and pre-emptive antifungal treating in CrAg+ persons with CD4+ T cell counts < 200 cells/µL.

Adjunctive sertraline for asymptomatic cryptococcal antigenemia: A randomized clinical trial.

Cryptococcal antigen (CrAg) screening in HIV-infected persons with CD4 < 100 cells/µl can reduce meningitis and death, yet preemptive fluconazole therapy fails in ∼25%. Sertraline has in vitro and in vivo activity against Cryptococcus and is synergistic with fluconazole in mice. We evaluated the efficacy and safety of sertraline in asymptomatic cryptococcal antigenemia. We conducted a randomized trial of asymptomatic CrAg-positive Ugandans from November 2017 to February 2018. All subjects received WHO standard therapy of fluconazole 800 mg for 2 weeks, then 400 mg for 10 weeks, then 200 mg through 24 weeks. Participants were randomized to receive adjunctive sertraline or placebo, given in once-weekly escalating 100 mg/day doses up to 400 mg/day, which was then given for 8 weeks, then tapered. The primary endpoint was meningitis-free 6-month survival. The data and safety monitoring board halted the trial after 21 subjects were enrolled due to safety concerns. Meningitis-free 6-month survival occurred in 9 of 11 of placebo participants and 10 of 10 of sertraline participants. However, seven serious adverse events (SAEs) occurred (n = 4 sertraline group; n = 3 placebo group). Three SAEs in the sertraline group presented with psychosis and aggressive behavioral changes with one meeting Hunter's criteria for serotonin syndrome while receiving 200 mg/day sertraline. Two transient psychoses were associated with antecedent fluconazole and sertraline interruption. The serotonin syndrome resolved within 1 day, but psychosis persisted for 4 months after sertraline discontinuation. Sertraline was associated with excess SAEs of psychosis. Due to early stopping, we were unable to determine any efficacy for cryptococcal antigenemia.

CNS infections in HIV.

PURPOSE OF REVIEW: Central nervous system (CNS) infections associated with HIV remain significant contributors to morbidity and mortality, particularly among people living with HIV (PLWH) in resource-limited settings worldwide. In this review, we discuss several recent important scientific discoveries in the prevention, diagnosis, and management around two of the major causes of CNS opportunistic infections-tuberculous meningitis (TBM) and cryptococcal meningitis including immune reconstitution syndrome (IRIS) associated with cryptococcal meningitis. We also discuss the CNS as a possible viral reservoir, highlighting Cerebrospinal fluid viral escape. RECENT FINDINGS: CNS infections in HIV-positive people in sub-Saharan Africa contribute to 15-25% of AIDS-related deaths. Morbidity and mortality in those is associated with delays in HIV diagnosis, lack of availability for antimicrobial treatment, and risk of CNS IRIS. The CNS may serve as a reservoir for replication, though it is unclear whether this can impact peripheral immunosuppression. SUMMARY: Significant diagnostic and treatment advances for TBM and cryptococcal meningitis have yet to impact overall morbidity and mortality according to recent data. Lack of early diagnosis and treatment initiation, and also maintenance on combined antiretroviral treatment are the main drivers of the ongoing burden of CNS opportunistic infections. The CNS as a viral reservoir has major potential implications for HIV eradication strategies, and also control of CNS opportunistic infections.

New Insights Into Cryptococcus Spp. Biology and Cryptococcal Meningitis.

PURPOSE OF REVIEW: Defective cell-mediated immunity is a major risk factor for cryptococcosis, a fatal disease if untreated. Cryptococcal meningitis (CM), the main presentation of disseminated disease, occurs through hematogenous spread to the brain from primary pulmonary foci, facilitated by yeast virulence factors. We revisit remarkable recent improvements in the prevention, diagnosis and management of CM. RECENT FINDINGS: Cryptococcal antigen (CrAg), main capsular polysaccharide of Cryptococcus spp. is detectable in blood and cerebrospinal fluid of infected patients with point of care lateral flow assays. Recent World Health Organization guidelines recommend 7-day amphotericin B plus flucytosine, then 7-day high dose (1200 mg/day) fluconazole for induction treatment of HIV-associated CM. Management of raised intracranial pressure, a consequence of CM, should rely mainly on daily therapeutic lumbar punctures until normalisation. In HIV-associated CM, following introduction of antifungal therapy, (re)initiation of antiretroviral therapy should be delayed by 4-6 weeks to prevent immune reconstitution inflammatory syndrome, common in CM. CM is a fatal disease whose diagnosis has recently been simplified. Treatment should always include antifungal combination therapy and management of raised intracranial pressure. Screening for immune deficiency should be mandatory in all patients with cryptococcosis.

Prospective cohort of AIDS patients screened for cryptococcal antigenaemia, pre-emptively treated and followed in Brazil.

BACKGROUND: Cryptococcal meningitis has a high morbidity and mortality among AIDS population. Cryptococcal antigen (CrAg) detection is considered an independent predictor for meningitis and death. Since 2011, the World Health Organization recommends CrAg screening for people living with HIV/AIDS (PLHAs) with CD4 counts <100-200 cells/µl. Its implementation is still limited in low-middle-income countries. We aimed to estimate the prevalence and predictors of CrAg positivity in PLHAs. We also evaluated outcomes among those who were CrAg-positive. METHODS: Prospective cohort conducted at an infectious diseases hospital, in Brazil. Adults with CD4 <200 cells/µl, without previous cryptococcal disease and regardless of symptoms, were enrolled from 2015 to 2018. CrAg tests were performed by LFA. Lumbar puncture was done in CrAg+ individuals and pre-emptive therapy was offered for those without meningitis. RESULTS: Of 214 individuals recruited, 88% were antiretroviral experienced, of which only 11.6% with viral suppression. Overall, CrAg prevalence was 7.9% (95% CI, 4.7-12.4). In CD4 ≤100 cells/µl group it was 7.5% (95% CI, 4.1-12.6) and 9.1% (95% CI, 3.4-19.0) in the group with CD4 101 to 199 cells/µl (p = 0.17). Prevalence in asymptomatic subjects was 5.3% (95% CI, 1.4-13.1). One among 17 CrAg+ participants had documented meningoencephalitis and no subclinical meningitis was detected. Adherence to pre-emptive treatment was 68.7% (11/16). There were no statistically significant differences in sociodemographic, clinical or laboratory characteristics to predict CrAg positivity. No case of cryptococcal disease was diagnosed among CrAg + subjects, followed by a median of 12 months. CONCLUSIONS: CrAg screening for severely immunosuppressed PLHAs in Brazil yielded a prevalence of 7.9%. No difference was found in the prevalence of CrAg stratified by CD4 values (CD4 <100 versus CD4 101-199 cells/µl). No clinical nor laboratory factors predicted CrAg positivity, corroborating the need for the implementation of universal CrAg screening for PLHAs with CD4 <200 cells/µl in similar settings.

Advanced HIV: diagnosis, treatment, and prevention.

Substantial progress has been made this century in bringing millions of people living with HIV into care, but progress for early HIV diagnosis has stalled. Individuals first diagnosed with advanced HIV have higher rates of mortality than those diagnosed at an earlier stage even after starting antiretroviral therapy (ART), resulting in substantial costs to health systems. Diagnosis of these individuals is hindered because many patients are asymptomatic, despite being severely immunosuppressed. Baseline CD4 counts and screening for opportunistic infections, such as tuberculosis and cryptococcus, is crucial because of the high mortality associated with these co-infections. Individuals with advanced HIV should have rapid ART initiation (except when found to have symptoms, signs, or a diagnosis of cryptococcal meningitis) and those in treatment failure should switch treatment. Overcoming barriers to testing and adherence through the development of differentiated care models and providing psychosocial support will be key in reaching populations at high risk of presenting with advanced HIV.

Evaluation of a national cryptococcal antigen screening program for HIV-infected patients in Uganda: A cost-effectiveness modeling analysis.

BACKGROUND: Cryptococcal meningitis accounts for 15% of AIDS-related mortality. Cryptococcal antigen (CrAg) is detected in blood weeks before onset of meningitis, and CrAg positivity is an independent predictor of meningitis and death. CrAg screening for patients with advanced HIV and preemptive treatment is recommended by the World Health Organization, though implementation remains limited. Our objective was to evaluate costs and mortality reduction (lives saved) from a national CrAg screening program across Uganda. METHODS: We created a decision analytic model to evaluate CrAg screening. CrAg screening was considered for those with a CD4<100 cells/µL per national and international guidelines, and in the context of a national HIV test-and-treat program where CD4 testing was not available. Costs (2016 USD) were estimated for screening, preemptive therapy, hospitalization, and maintenance therapy. Parameter assumptions were based on large prospective CrAg screening studies in Uganda, and clinical trials from sub Saharan Africa. CrAg positive (CrAg+) persons could be: (a) asymptomatic and thus eligible for preemptive treatment with fluconazole; or (b) symptomatic with meningitis with hospitalization. RESULTS: In the base case model for 1 million persons with a CD4 test annually, 128,000 with a CD4<100 cells/µL were screened, and 8,233 were asymptomatic CrAg+ and received preemptive therapy. Compared to no screening and treatment, CrAg screening and treatment in the base case cost $3,356,724 compared to doing nothing, and saved 7,320 lives, for a cost of $459 per life saved, with the $3.3 million in cost savings derived from fewer patients developing fulminant meningitis. In the scenario of a national HIV test-and-treat program, of 1 million HIV-infected persons, 800,000 persons were screened, of whom 640,000 returned to clinic, and 8,233 were incident CrAg positive (CrAg prevalence 1.4%). The total cost of a CrAg screening and treatment program was $4.16 million dollars, with 2,180 known deaths. Conversely, without CrAg screening, the cost of treating meningitis was $3.09 million dollars with 3,806 deaths. Thus, despite the very low CrAg prevalence of 1.4% in the general HIV-infected population, and inadequate retention-in-care, CrAg screening averted 43% of deaths from cryptococcal meningitis at a cost of $662 per death averted. CONCLUSION: CrAg screening and treatment programs are cost-saving and lifesaving, assuming preemptive treatment is 77% effective in preventing death, and could be adopted and implemented by ministries of health to reduce mortality in those with advanced HIV disease. Even within HIV test-and-treat programs where CD4 testing is not performed, and CrAg prevalence is only 1.4%, CrAg screening is cost-effective.

Impact of Routine Cryptococcal Antigen Screening and Targeted Preemptive Fluconazole Therapy in Antiretroviral-naive Human Immunodeficiency Virus-infected Adults With CD4 Cell Counts <100/µL: A Systematic Review and Meta-analysis.

Cryptococcal antigen (CrAg) screening and targeted preemptive fluconazole in antiretroviral-naive human immunodeficiency virus-infected adults with CD4 cell counts <100/µL seems promising as a strategy to reduce the burden of cryptococcal meningitis (CM). We searched MEDLINE, EMBASE, and Web of Science and used random-effect meta-analysis to assess the prevalence of blood CrAg positivity (31 studies; 35644 participants) and asymptomatic CM in CrAg-positive participants and the incidence of CM and the all-cause mortality rate in screened participants. The pooled prevalence of blood CrAg-positivity was 6% (95% confidence interval [CI], 5%-7%), and the prevalence of asymptomatic CM in CrAg-positive participants was 33% (95% CI, 21%-45%). The incidence of CM was 21.4% (95% CI, 11.6%-34.4%) without preemptive fluconazole and 5.7% (95% CI, 3.0%-9.7%) with preemptive fluconazole therapy initiated at 800 mg/d. In CrAg-positive participants, postscreening lumbar puncture before initiating preemptive fluconazole at 800 mg/d further reduced the incidence of CM to null and showed some survival benefits. However, the all-cause mortality rate remained significantly higher in CrAg-positive than in CrAg-negative participants (risk ratio, 2.2; 95% CI, 1.7-2.9; P < .001).

Cryptococcal meningitis following umbilical cord blood transplantation, association between the occurrence of cryptococcal infection and tacrolimus discontinuation among allogeneic hematopoietic stem cell recipients.

Few cases of cryptococcal infection following umbilical cord blood transplantation (UCBT) have been reported. We report a case, where cryptococcal infection occurred soon after rapidly reducing the dose of tacrolimus in a UCBT recipient who received micafungin prophylaxis during the early phase of transplantation. The etiology of cryptococcal infection following allogeneic hematopoietic stem cell transplantation (allo-HSCT), including UCBT, might be associated with rapid dose-reduction of calcineurin inhibitors, such as tacrolimus during early phase of allo-HSCT. To our knowledge, this is the first English-language report to describe in detail a case of cryptococcal meningitis with fungemia during early phase of UCBT.

Cryptococcal Meningitis Diagnostics and Screening in the Era of Point-of-Care Laboratory Testing.

Over the past ten years, standard diagnostics for cryptococcal meningitis in HIV-infected persons have evolved from culture to India ink to detection of cryptococcal antigen (CrAg), with the recent development and distribution of a point-of-care lateral flow assay. This assay is highly sensitive and specific in cerebrospinal fluid (CSF), but is also sensitive in the blood to detect CrAg prior to meningitis symptoms. CrAg screening of HIV-infected persons in the blood prior to development of fulminant meningitis and preemptive treatment for CrAg-positive persons are recommended by the World Health Organization and many national HIV guidelines. Thus, CrAg testing is occurring more widely, especially in resource-limited laboratory settings. CrAg titer predicts meningitis and death and could be used in the future to customize therapy according to burden of infection.