Cryptococcal Antigen in Serum and Cerebrospinal Fluid for Detecting Cryptococcal Meningitis in Adults Living With Human Immunodeficiency Virus: Systematic Review and Meta-Analysis of Diagnostic Test Accuracy Studies

HIV-associated disseminated cryptococcosis-An unusual clinical and diagnostic picture with successful cure by single dose liposomal amphotericin B treatment

BACKGROUND

Cryptococcosis is an invasive, opportunistic fungal infection seen especially in human immunodeficiency virus (HIV) infected patients. Cryptococcal meningitis (CM) is the second leading cause of mortality in HIV patients. We report a case of disseminated cryptococcosis presenting with altered mental status in a newly diagnosed HIV infection.

METHODS AND RESULTS

A 50-year-old with a short history of altered mental sensorium and a history of low-grade fever and weight loss for few months presented at a tertiary care hospital in North India. He was detected positive for HIV-1. Cryptococcal antigen (CRAG) was positive in Cerebrospinal fluid (CSF), and negative in serum. The fungal culture in CSF was sterile while the fungal blood culture grew Cryptococcus neoformans. The patient was treated with single high-dose Liposomal Amphotericin B (LAmB) therapy followed by Fluconazole and Flucytosine for the next two weeks followed by fluconazole daily for consolidation and maintenance therapy. Antiretroviral therapy (ART) was started 4 weeks after induction therapy. After 6 months, the patient is doing fine.

CONCLUSION

Single dose LAmB along with the backbone of fluconazole and flucytosine appears promising in disseminated cryptococcal infection in HIV-infected individuals.

Central nervous system infections in the tropics

PURPOSE OF REVIEW

Emerging and re-emerging central nervous system (CNS) infections are a major public health concern in the tropics. The reasons for this are myriad; climate change, rainfall, deforestation, increased vector density combined with poverty, poor sanitation and hygiene. This review focuses on pathogens, which have emerged and re-emerged, with the potential for significant morbidity and mortality.

RECENT FINDINGS

In recent years, multiple acute encephalitis outbreaks have been caused by Nipah virus, which carries a high case fatality. Arboviral infections, predominantly dengue, chikungunya and Zika are re-emerging increasingly especially in urban areas due to changing human habitats, vector behaviour and viral evolution. Scrub typhus, another vector borne disease caused by the bacterium Orientia tsutsugamushi , is being established as a leading cause of CNS infections in the tropics.

SUMMARY

A syndromic and epidemiological approach to CNS infections in the tropics is essential to plan appropriate diagnostic tests and management. Rapid diagnostic tests facilitate early diagnosis and thus help prompt initiation and focusing of therapy to prevent adverse outcomes. Vector control, cautious urbanization and deforestation, and reducing disturbance of ecosystems can help prevent spread of vector-borne diseases. Regional diagnostic and treatment approaches and specific vaccines are required to avert morbidity and mortality.

Clinical treatment of cryptococcal meningitis: an evidence-based review on the emerging clinical data

Cryptococcal meningitis (CM) is a fatal fungal central nervous system (CNS) infection caused by Cryptococcus infecting the meninges and/or brain parenchyma, with fever, headache, neck stiffness, and visual disturbances as the primary clinical manifestations. Immunocompromised individuals with human immunodeficiency virus (HIV) infection or who have undergone organ transplantation, as well as immunocompetent people can both be susceptible to CM. Without treatment, patients with CM may have a mortality rate of up to 100% after hospital admission. Even after receiving therapy, CM patients may still suffer from problems such as difficulty to cure, poor prognosis, and high mortality. Therefore, timely and effective treatment is essential to improve the mortality and prognosis of CM patients. Currently, the clinical outcomes of CM are frequently unsatisfactory due to limited drug choices, severe adverse reactions, drug resistance, etc. Here, we review the research progress of CM treatment strategies and discuss the suitable options for managing CM, hoping to provide a reference for physicians to select the most appropriate treatment regimens for CM patients.

Clinical, radiological, and laboratory features of HIV-negative pulmonary cryptococcosis with regard to serum lateral flow assay

Introduction

Cryptococcosis is the second most common invasive yeast infection in China. Pulmonary cryptococcosis (PC) is difficult to diagnose due to the lack of specific clinical features and the limitation of diagnostic techniques. Although lateral flow assay was very useful in diagnosing cryptococcal infection, quite a few patients with PC presented negative serum lateral flow assay (sLFA).

Methods

We conducted a retrospective study of HIV-negative patients who were diagnosed with PC in our hospital over the past decade to explore the potential relationship between the clinical profiles and sLFA in PC.

Results

In total, 112 patients with sLFA tested were enrolled in this study, of which 58.93% were male. The positivity rate of sLFA for PC was 91.07%. The extent of pulmonary lesions was positively correlated with sLFA grade (Spearman r = 0.268, p < 0.01). Solitary nodule (SN) and pneumonia were the most common imaging findings in PC with negative and positive sLFA respectively. Among 65 symptomatic PC patients, 14 presented with fever and had higher hypersensitive C-reactive protein (hsCRP) level and more extensive pulmonary involvement (Mann-Whitney U test, p < 0.05) than those without fever. Symptomatic PC patients were more likely to have positive results of sLFA (Mann-Whitney U test, p = 0.05) compared against asymptomatic ones.

Discussion

In conclusion, negative sLFA cannot exclude PC in patients with a solitary nodule in lung. Positive sLFA is more reliable in diagnosing PC in symptomatic patients with diffused lesions in lung who generally experience a more severe systemic inflammatory reaction.

Anti-GM-CSF autoantibodies predict outcome of cryptococcal meningitis in patients not infected with HIV: A cohort study

OBJECTIVES

To explore the seroprevalence of anti-granulocyte-macrophage colony-stimulating factor (GM-CSF) autoantibodies in non-HIV cryptococcal meningitis (CM) and assess its predictive value for survival.

METHODS

This is a retrospective study of 12 years of non-HIV CM. We detected serum anti-GM-CSF autoantibodies, and evaluated the clinical features and outcomes, together with the exploration of prognostic factors for 2-week and 1-year survival.

RESULTS

A total of 584 non-HIV CM cases were included. 301 of 584 patients (51.5%) were phenotypically healthy. 264 Cryptococcus isolates were obtained from cerebrospinal fluid (CSF) culture, of which 251 were identified as C. neoformans species complex and 13 as C. gattii species complex. Thirty-seven of 455 patients (8.1%) tested positive for serum anti-GM-CSF autoantibodies. Patients with anti-GM-CSF autoantibodies were more susceptible to C. gattii species complex infection (66.7% vs. 6.3%; p < 0.001) and more likely to develop pulmonary mass lesions with a diameter >3 centimetres (42.9% vs. 6.5%; p 0.001). Of 584 patients 16 (2.7%) died within 2 weeks, 77 of 563 patients (13.7%) died at 1 year, and 93 of 486 patients (19.1%) lived with disabilities at 1 year. Univariant Cox regression analysis found that anti-GM-CSF autoantibodies were associated with lower 1-year survival (HR, 2.66; 95% CI, 1.34-5.27; p 0.005). Multivariable Cox proportional hazards modelling revealed that CSF cryptococcal antigen titres ≥1:1280 were associated with both, reduced 2-week and 1-year survival rates (HR, 5.44; 95% CI, 1.23-24.10; p 0.026 and HR, 5.09; 95% CI, 1.95-13.26; p 0.001).

DISCUSSION

Presence of serum anti-GM-CSF autoantibodies is predictive of poor outcomes, regardless of host immune status and the causative Cryptococcus species complex.

The diagnosis of central nervous system infections in resource-limited settings and the use of novel and molecular diagnostic platforms to improve diagnosis

INTRODUCTION

Central nervous system infections (CNSI) disproportionately affect individuals in low-resource settings where diagnosis is challenging; large proportions of patients never receive a confirmed microbiological diagnosis resulting in inadequate management and high mortality. The epidemiology of CNSI varies globally and conventional diagnostics deployed in resource-limited settings have significant limitations, with an urgent need for improved diagnostic strategies.

AREAS COVERED

This review describes molecular platforms and other novel diagnostics used in the diagnosis of CNSI that are applicable to resource-limited settings. An extensive literature search of Medline and PubMed was performed. The emphasis is on investigations targeting infections of relevance to resource-limited settings either due to variation in regional CNSI epidemiology or due to increased prevalence in patients with immunosuppression. This includes commercially available multiplex PCR platforms, mycobacterial PCR platforms, and rapid diagnostics tests. To offer a framework for the optimal implementation in clinical settings, existing evidence highlighting the advantages and limitations of available platforms is reviewed.

EXPERT OPINION

The implementation of molecular platforms and other novel diagnostics has the potential to transform CNSI diagnosis in resource-limited settings, with several examples of successful rollout of novel diagnostics such as Xpert MTB/RIF Ultra and cryptococcal antigen testing.

Development and validation of quantitative PCR assays for HIV-associated cryptococcal meningitis in sub-Saharan Africa: a diagnostic accuracy study

BACKGROUND

HIV-associated cryptococcal meningitis is the second leading cause of AIDS-related deaths, with a 10-week mortality rate of 25-30%. Fungal load assessed by colony-forming unit (CFU) counts is used as a prognostic marker and to monitor response to treatment in research studies. PCR-based assessment of fungal load could be quicker and less labour-intensive. We sought to design, optimise, and validate quantitative PCR (qPCR) assays for the detection, identification, and quantification of Cryptococcus infections in patients with cryptococcal meningitis in sub-Saharan Africa.

METHODS

We developed and validated species-specific qPCR assays based on DNA amplification of QSP1 (QSP1A specific to Cryptococcus neoformans, QSP1B/C specific to Cryptococcus deneoformans, and QSP1D specific to Cryptococcus gattii species) and a pan-Cryptococcus assay based on a multicopy 28S rRNA gene. This was a longitudinal study that validated the designed assays on cerebrospinal fluid (CSF) of 209 patients with cryptococcal meningitis at baseline (day 0) and during anti-fungal therapy (day 7 and day 14), from the AMBITION-cm trial in Botswana and Malawi (2018-21). Eligible patients were aged 18 years or older and presenting with a first case of cryptococcal meningitis.

FINDINGS

When compared with quantitative cryptococcal culture as the reference, the sensitivity of the 28S rRNA was 98·2% (95% CI 95·1-99·5) and of the QSP1 assay was 90·4% (85·2-94·0) in CSF at day 0. Quantification of the fungal load with QSP1 and 28S rRNA qPCR correlated with quantitative cryptococcal culture (R2=0·73 and R2=0·78, respectively). Both Botswana and Malawi had a predominant C neoformans prevalence of 67% (95% CI 55-75) and 68% (57-73), respectively, and lower C gattii rates of 21% (14-31) and 8% (4-14), respectively. We identified ten patients that, after 14 days of treatment, harboured viable but non-culturable yeasts based on QSP1 RNA detection (without any positive CFU in CSF culture).

INTERPRETATION

QSP1 and 28S rRNA assays are useful in identifying Cryptococcus species. qPCR results correlate well with baseline quantitative cryptococcal culture and show a similar decline in fungal load during induction therapy. These assays could be a faster alternative to quantitative cryptococcal culture to determine fungal load clearance. The clinical implications of the possible detection of viable but non-culturable cells in CSF during induction therapy remain unclear.

FUNDING

European and Developing Countries Clinical Trials Partnership; Swedish International Development Cooperation Agency; Wellcome Trust/UK Medical Research Council/UKAID Joint Global Health Trials; and UK National Institute for Health Research.

Nanopore targeted sequencing-based diagnosis of central nervous system infections in HIV-infected patients

BACKGROUND

Early and accurate etiological diagnosis is very important for improving the prognosis of central nervous system (CNS) infections in human immunodeficiency virus (HIV)-infected patients. The goal is not easily achieved by conventional microbiological tests. We developed a nanopore targeted sequencing (NTS) platform and evaluated the diagnostic performance for CNS infections in HIV-infected patients, with special focus on cryptococcal meningitis (CM). We compared the CM diagnostic performance of NTS with conventional methods and cryptococcal polymerase chain reaction (PCR).

METHODS

This study included 57 hospitalized HIV-infected patients with suspected CNS infections from September 2018 to March 2022. The diagnosis established during hospitalization includes 27 cases of CM, 13 CNS tuberculosis, 5 toxoplasma encephalitis, 2 cytomegalovirus (CMV) encephalitis and 1 Varicella-zoster virus (VZV) encephalitis. The 2 cases of CMV encephalitis also have co-existing CM. Target-specific PCR amplification was used to enrich pathogen sequences before nanopore sequencing. NTS was performed on stored cerebrospinal fluid (CSF) samples and the results were compared with the diagnosis during hospitalization.

RESULTS

53 (93.0%) of the patients were male. The median CD4 cell count was 25.0 (IQR: 14.0-63.0) cells/uL. The sensitivities of CSF culture, India ink staining, cryptococcal PCR and NTS for CM were 70.4% (95%CI: 51.5 - 84.1%), 76.0% (95%CI: 56.6 - 88.5%), 77.8% (59.2 - 89.4%) and 85.2% (95%CI: 67.5 - 94.1%), respectively. All those methods had 100% specificity for CM. Our NTS platform could identify Cryptococcus at species level. Moreover, NTS was also able to identify all the 5 cases of toxoplasma encephalitis, 2 cases of CMV encephalitis and 1 VZV encephalitis. However, only 1 of 13 CNS tuberculosis cases was diagnosed by NTS, and so did Xpert MTB/RIF assay.

CONCLUSIONS

NTS has a good diagnostic performance for CM in HIV-infected patients and may have the ability of simultaneously detecting other pathogens, including mixed infections. With continuing improving of the NTS platform, it may be a promising alterative microbiological test for assisting with the diagnosis of CNS infections.

Orofacial Cryptococcosis: A Challenging Clinical Report and a Systematic Analysis of the Literature

Cryptococcosis is a neglected fungal disease. The scarcity of studies on oral cryptococcosis is certainly due to rarity and/or underreporting of the disease, especially in Brazil. We describe an example of orofacial cryptococcosis affecting a 57-year-old man after heart transplantation, who presented with multiple erythematous ulcers and erosions distributed in the chin, nasal cavity, labial mucosa, hard palate, and buccal vestibule. Computed tomography revealed opacities and micronodules in the lungs. Histopathological features of the oral and pulmonary lesions were compatible with Cryptococcus spp. Amphotericin B and fluconazole were used for treatment during hospitalization and itraconazole for prolonged therapy after hospital discharge. The patient has been under follow up for 6 months without signs of disease. According to a review conducted in PubMed, Web of Science, Scopus, Embase, and LILACS for data analysis of oral cryptococcosis, 26 reports were described in the literature. Predilection for men was observed (85%), with a male:female ratio of 5.5:1. The mean age of the individuals was 49 ± 15.3 years. Oral cryptococcosis mostly presented as an ulcer (n = 17). The palate and tongue were the most affected sites (n = 9 for each). Amphotericin B was the primary therapy utilized in most patients. Seventeen (65%) individuals survived. Knowledge of the clinicodemographic aspects of oral cryptococcosis is important for clinicians in decision making and surveillance.

Concomitant of Cryptococcal Meningitis and COVID-19 in a Female Patient with Primary Nephrotic Syndrome and Type 2 Diabetes

Background

Patients with primary nephrotic syndrome (PNS) are at an increased risk of developing various infections due to the long-term use of immunosuppressive agents. Cryptococcal meningitis (CM) is an uncommon but severe complication that can occur in patients with PNS, particularly those receiving immunosuppressive medications.

Case Description

This case report describes a middle-aged female patient with PNS and type 2 diabetes mellitus (T2DM) who developed CM. She received a combination regimen of cyclophosphamide and prednisone, achieving partial remission of PNS. However, she later returned to the hospital with high fever and headache. At admission, her nasopharyngeal swab test was positive for severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) and she received therapy of dexamethasone and favipiravir, but her fever and headache were not improved. Following a lumbar puncture was performed for her and CM was diagnosed based on a positive Cryptococcus culture in the cerebrospinal fluid. The patient's cyclophosphamides were temporarily discontinued, and antifungal therapy with amphotericin B liposome and fluconazole was initiated. Despite a noticeable increase in her blood glucose levels due to infection during her hospitalization, she showed improvement with intensified glycemic control treatment. The anti-infection showed significant effectiveness, and the patient's proteinuria remained stable during follow-up.

Conclusion

The patient with PNS and T2DM was concurrently diagnosed with both CM and coronavirus disease 2019 (COVID-19), marking the first reported case of such co-infections in these patients. Prompt diagnosis and appropriate antifungal therapy are crucial for improved outcomes of PNS patients with CM and COVID-19.

Pleural cryptococcosis diagnosed by pleural biopsy in an immunocompromised patient: a case report

Objective

The aim of this study is to report an isolated pleural cryptococcosis with pleural effusion as the only manifestation, confirmed by pleural biopsy in a patient with thymoma combined with myasthenia gravis, who developed pleural effusion of unknown origin after long-term glucocorticoids and tacrolimus therapy.

Methods

Pathological examination of the right pleural biopsy tissue from a patient with unexplained recurrent pleural effusion was implemented. Morphological analysis of the fungal component and metagenomic next-generation sequencing (mNGS) on the pleural tissue were performed.

Results

A biopsy specimen of the right pleura revealed numerous yeast-like organisms surrounded by mucous capsules and Cryptococcus neoformans was detected by mNGS with a species-specific read number (SSRN) of 4, confirming the diagnosis of pleural cryptococcosis. Pleural effusion was eliminated with amphotericin B and fluconazole, and healthy status was maintained at the time of review 1 year later.

Conclusion

Cryptococcosis, manifested by simple pleural effusion, is extremely rare, but when repeated pleural effusion occurs in immunocompromised patients or in patients with malignant tumors, the possibility of cryptococcosis should be treated with high vigilance and pleural biopsy is recommended if necessary in order to confirm the diagnosis.

Current Epidemiology and Clinical Features of Cryptococcus Infection in Patients Without Human Immunodeficiency Virus: A Multicenter Study in 46 Hospitals in Australia and New Zealand

BACKGROUND

Patients without human immunodeficiency virus (HIV) are increasingly recognized as being at risk for cryptococcosis. Knowledge of characteristics of cryptococcosis in these patients remains incomplete.

METHODS

We conducted a retrospective study of cryptococcosis in 46 Australian and New Zealand hospitals to compare its frequency in patients with and without HIV and describe its characteristics in patients without HIV. Patients with cryptococcosis between January 2015 and December 2019 were included.

RESULTS

Of 475 patients with cryptococcosis, 90% were without HIV (426 of 475) with marked predominance in both Cryptococcus neoformans (88.7%) and Cryptococcus gattii cases (94.3%). Most patients without HIV (60.8%) had a known immunocompromising condition: cancer (n = 91), organ transplantation (n = 81), or other immunocompromising condition (n = 97). Cryptococcosis presented as incidental imaging findings in 16.4% of patients (70 of 426). The serum cryptococcal antigen test was positive in 85.1% of tested patients (319 of 375); high titers independently predicted risk of central nervous system involvement. Lumbar puncture was performed in 167 patients to screen for asymptomatic meningitis, with a positivity rate of 13.2% where meningitis could have been predicted by a high serum cryptococcal antigen titer and/or fungemia in 95% of evaluable cases. One-year all-cause mortality was 20.9% in patients without HIV and 21.7% in patients with HIV (P = .89).

CONCLUSIONS

Ninety percent of cryptococcosis cases occurred in patients without HIV (89% and 94% for C. neoformans and C. gattii, respectively). Emerging patient risk groups were evident. A high level of awareness is warranted to diagnose cryptococcosis in patients without HIV.

Diagnostic Performance of Metagenomic Next-Generation Sequencing in Central Nervous System Cryptococcosis Using Cerebrospinal Fluid

Purpose

Metagenomic next-generation sequencing (mNGS) has been widely used to diagnose infectious diseases. However, there are few studies on its diagnostic performance in the central nervous system (CNS) cryptococcosis. This study examined the diagnostic efficacy of mNGS in identifying Cryptococcus spp. in cerebrospinal fluid (CSF) samples.

Patients and Methods

From March 2021 to March 2023, 290 patients with suspected CNS infection were recruited from the First Affiliated Hospital, School of Medicine, Zhejiang University, and 74 patients were ultimately included in the study. Lastly, 22 patients with CNS cryptococcosis were included. Of these patients, 25 CSF samples were enrolled. The diagnostic performance of conventional assays [including India ink, cryptococcal antigen (CrAg) testing, and culture] and mNGS was evaluated for CNS cryptococcosis.

Results

In the 25 samples collected, the coincidence rates of mNGS with India ink, CrAg, and culture were 64.0% (16/25), 80.0% (20/25), and 80.0% (20/25), respectively. Without antifungal drug exposure, the coincidence rates were increased to 66.7% (10/15), 100.0% (15/15), and 93.3% (14/15), respectively. The coincidence rates after antifungal therapy were all decreased to 60.0% (6/10), 50.0% (5/10), and 60.0% (6/10), respectively. Moreover, in the 25 samples, the sensitivity of mNGS reached 80.0%, and of India ink, CrAg testing, and culture were 68.0, 100.0, and 60.0%, respectively. The mNGS showed an excellent positive rate (100.0%) in the 15 samples collected without antifungal drug exposure, which was significantly higher than the antifungal drug-exposed group (n = 10) (50.0%) (P = 0.005). The reads of Cryptococcus spp. before antifungal therapy were significantly higher than after it (median, 25,915 vs 2, P = 0.008).

Conclusion

mNGS is an effective tool for diagnosing CNS cryptococcosis using CSF; however, its sensitivity decreases considerably in patients who have been effectively treated with antifungal drugs.

Clinical metagenomics-assisted diagnosis of relapsed HIV-associated cryptococcal meningitis

To date, the identification of crypotococcal relapse remains clinically challenging as it often has similar manifestation with paradoxical immune reconstitution inflammatory syndrome. This study reports on the use of metagenomics assisted next generation sequencing to aid in diagnosing recurrent cryptococcal meningitis in an person living with HIV experiencing recurring symptoms, despite negative culture results for Cryptococcus neoformans in the cerebrospinal fluid. Although fungal culture was negative, when reads from metagenomic and metatranscriptomic sequencing performed on the Day 308 cerebrospinal fluid sample were mapped onto the genome from the Day 4 isolate, 589 specific reads were identified. NCBI BLAST search also revealed Cryptococcus-specific 18S/25S/28S ribosomal RNA, indicating a relapse of the disease.

Diagnosis, Prevention, and Treatment of Infections in Kidney Transplantation

Kidney transplant often is complicated by infections in the recipient from therapy-related and patient-related risk factors. Infections in kidney transplant recipients are associated with increased morbidity, mortality, and allograft dysfunction. There is a predictable timeline after kidney transplant regarding the types of pathogens causing infections, reflecting the net state of immunosuppression. In the early post-transplant period, bacterial infections comprise two thirds of all infections, followed by viral and fungal infections. Infections occurring early after kidney transplantation are generally the result of postoperative complications. In most cases, opportunistic infections occur within 6 months after kidney transplantation. They may be caused by a new infection, a donor-derived infection, or reactivation of a latent infection. Community-acquired pneumonia, upper respiratory tract infections, urinary tract infections, and gastrointestinal infections are the most common infections in the late period after transplantation when the net immunosuppression is minimal. It is crucial to seek information on the time after transplant, reflecting the net state of immunosuppression, previous history of exposure/infections, geography, and seasonal outbreaks. It is imperative that we develop regionally specific guidelines on screening, prevention, and management of infections after kidney transplantation.

Cryptococcal Meningitis Developing in a Patient with Neurosarcoidosis

Cryptococcal meningitis is a critical disease that occasionally involves immunosuppressed patients. We herein report a 79-year-old Japanese man who received low-dose prednisolone therapy for neurosarcoidosis and panhypopituitarism. He presented a 10-day history of a fever and altered mental status. The FilmArray® Meningitis/Encephalitis Panel and serum cryptococcal antigen tests were both negative, but the cerebrospinal fluid sample became positive for Cryptococcus neoformans after seven-day incubation. After the diagnosis of cryptococcal meningitis, we successfully treated the patient with a recommended treatment regimen. When an immunocompromised patient presents with a subacute fever accompanying any central nervous symptoms, cryptococcal meningitis should be screened for.

Advanced HIV disease: A review of diagnostic and prophylactic strategies

BACKGROUND

Despite expanded access to antiretroviral therapy (ART) and the rollout of the World Health Organization's (WHO) 'test-and-treat' strategy, the proportion of people with HIV (PWH) presenting with advanced HIV disease (AHD) remains unchanged at approximately 30%. Fifty percent of persons with AHD report prior engagement to care. ART failure and insufficient retention in HIV care are major causes of AHD. People living with AHD are at high risk for opportunistic infections and death. In 2017, the WHO published guidelines for the management of AHD that included a comprehensive package of care for screening and prophylaxis of major opportunistic infections (OIs). In the interim, ART regimens have evolved: integrase inhibitors are first-line therapy globally, and the diagnostic landscape is evolving. The objective of this review is to highlight novel point-of-care (POC) diagnostics and treatment strategies that can facilitate OI screening and prophylaxis for persons with AHD.

METHODS

We reviewed the WHO guidelines for recommendations for persons with AHD. We summarized the scientific literature on current and emerging diagnostics, along with emerging treatment strategies for persons with AHD. We also highlight the key research and implementation gaps together with potential solutions.

RESULTS

While POC CD4 testing is being rolled out in order to identify persons with AHD, this alone is insufficient; implementation of the Visitect CD4 platform has been challenging given operational and test interpretation issues. Numerous non-sputum POC TB diagnostics are being evaluated, many with limited sensitivity. Though imperfect, these tests are designed to provide rapid results (within hours) and are relatively affordable for resource-poor settings. While novel POC diagnostics are being developed for cryptococcal infection, histoplasmosis and talaromycosis, implementation science studies are urgently needed to understand the clinical benefit of these tests in the routine care.

CONCLUSIONS

Despite progress with HIV treatment and prevention, a persistent 20%-30% of PWH present to care with AHD. Unfortunately, these persons with AHD continue to carry the burden of HIV-related morbidity and mortality. Investment in the development of additional POC or near-bedside CD4 platforms is urgently needed. Implementation of POC diagnostics theoretically could improve HIV retention in care and thereby reduce mortality by overcoming delays in laboratory testing and providing patients and healthcare workers with timely same-day results. However, in real-world scenarios, people with AHD have multiple comorbidities and imperfect follow-up. Pragmatic clinical trials are needed to understand whether these POC diagnostics can facilitate timely diagnosis and treatment, thereby improving clinical outcomes such as HIV retention in care.

Retrospective analysis of pulmonary cryptococcosis and extrapulmonary cryptococcosis in a chinese tertiary hospital

Cryptococcosis is an invasive fungal disease with increased morbidity in China over the past two decades. Cryptococci can infect immunocompromised hosts as well as immunocompetent ones. In this study, we reviewed data of 71 inpatients with cryptococcosis at Ningbo First Hospital from May 2010 to May 2020 and compared the clinical profiles of pulmonary cryptococcosis (PC) and extrapulmonary cryptococcosis (EPC). Of 71 patients (38 males, 33 females), 70 were non-HIV. The annual inpatient population increased dramatically, especially in the PC group. PC was confirmed in 77.46% (55/71) of cases by pathology. The rest were EPC including intracranial infection (15.49%, 11/71) and cryptococcemia (7.04%, 5/71). Compared with PC, a larger proportion of EPC patients were found to have immunocompromised conditions judged by predisposing factors (p < 0.01), or detectable humoral or cellular immunodeficiency. Fever and headache were more common in EPC patients (p < 0.001). Patients with EPC had lower serum sodium level (p = 0.041), lower monocyte counts (p = 0.025) and higher C-reactive protein (p = 0.012). In our study, the sensitivity of cryptococcus antigen detection for EPC was 100% regardless of sample type, while serum lateral flow assay (LFA) tested negative in 25% (5/20) of PC. Immunocompromised hosts are more likely to suffer from EPC than PC.

Preemptive Therapy in Cryptococcosis Adjusted for Outcomes

Cryptococcosis is one of the most serious opportunistic diseases in patients living with HIV. For this reason, early diagnosis and appropriate treatment are important.

OBJECTIVES

The aim of the study was to understand the development of patients diagnosed with cryptococcosis by detection of Cryptococcus antigen in serum by lateral flow assay (CrAg LFA) without nervous system involvement and with treatment in accordance with the results.

MATERIALS AND METHODS

A retrospective, longitudinal, analytical study was performed. Seventy patients with cryptococcosis initially diagnosed by serum CrAg LFA without meningeal involvement between January 2019 and April 2022 were analyzed for medical records. The treatment regimen was adapted to the results of blood culture, respiratory material, and pulmonary tomography imaging.

RESULTS

Seventy patients were included, 13 had probable pulmonary cryptococcosis, 4 had proven pulmonary cryptococcosis, 3 had fungemia, and 50 had preemptive therapy without microbiological or imaging findings compatible with cryptococcosis. Among the 50 patients with preemptive therapy, none had meningeal involvement or cryptococcosis recurrences to date.

CONCLUSION

Preemptive therapy avoided progression to meningitis in CrAg LFA-positive patients. Preemptive therapy with dose adjustment of fluconazole in patients with the mentioned characteristics was useful despite the use of lower doses than recommended.

Diagnosis and Treatment of Fungal Infections in Lung Transplant Recipients

Fungal infections are a significant source of morbidity in the lung transplant population via direct allograft damage and predisposing patients to the development of chronic lung allograft dysfunction. Prompt diagnosis and treatment are imperative to limit allograft damage. This review article discusses incidence, risk factors, and symptoms with a specific focus on diagnostic and treatment strategies in the lung transplant population for fungal infections caused by Aspergillus, Candida, Coccidioides, Histoplasma, Blastomyces, Scedosporium/Lomentospora, Fusarium, and Pneumocystis jirovecii. Evidence for the use of newer triazole and inhaled antifungals to treat isolated pulmonary fungal infections in lung transplant recipients is also discussed.

The incidence of histoplasmosis and cryptococcal antigenemia among patients attending a large HIV clinic in Trinidad

Our aim was to determine the incidence disseminated histoplasmosis and cryptococcal antigenemia among 280 patients with a CD4<350 cells/mm³ attending a large HIV clinic in Trinidad over the period November 2021-June 2022. Sera were screened for cryptococcal antigen (CrAg) using the Immy CrAg Immunoassay (EIA) and the Immy CrAg lateral flow assay (LFA). Urine was screened for Histoplasma antigen using the Immy EIA and the Optimum Imaging Diagnostics (OIDx) LFA. For the purposes of analysis, it was assumed, that all patients with positive urine Histoplasma antigen tests by both EIA and LFA and those with a single positive urine Histoplasma antigen test and clinical features of disseminated histoplasmosis were true positives. The incidence of probable disseminated histoplasmosis and cryptococcal antigenemia were 6.4% (18/280) and 2.5% (7/280) respectively. The sensitivity and specificity of the Immy Histoplasma EIA were 100% (95% CI, 81.5%-100%) and 98.5% (95% CI, 96.1% - 99.6%) respectively as compared to the OIDx Histoplasma LFA of 88.9% (95% CI, 65.3% - 98.6%) and 93.9% (95% CI, 90.3% - 96.5%) respectively, with substantial agreement between the 2 test kits (Kappa value = 0.763; 95% CI 0.685, 0.841). Testing for disseminated histoplasmosis in HIV patients is important in endemic areas.

Diagnostic accuracy of cryptococcal antigen test in pulmonary cryptococcosis: a protocol for a systematic review and meta-analysis

BACKGROUND

The cryptococcal antigen (CrAg) test was proposed as a rapid diagnostic tool to identify cryptococcal meningitis in patients suffering from AIDS. Several studies have demonstrated its diagnostic performance in cryptococcal meningitis. However, the diagnostic performance of the CrAg test in serum or bronchoalveolar lavage fluid in patients with pulmonary cryptococcosis remains uncertain. Therefore, the purpose of this systematic review is to summarise the evidence concerning diagnostic performance of the CrAg test in patients with pulmonary cryptococcosis.

METHODS AND ANALYSIS

Databases such as PubMed, EMBASE, Cochrane Database of Systematic Reviews, Web of Science, ClinicalTrials.gov, International Clinical Trials Registry Platform, Wanfang Database and China National Knowledge Infrastructure will be searched systematically. The titles and abstracts will be reviewed by two independent reviewers. The Quality Assessment of Diagnostic Accuracy Studies 2 tool will be used to evaluate the risk of bias and clinical applicability of each study. Potential sources of heterogeneity will be investigated through visual inspection of the paired forest plots and summary receiver operating characteristic plots. The pooled summary statistics for the area under the curve, sensitivities, specificities, likelihood ratios and diagnostic ORs with 95% CI will be reported.

ETHICS AND DISSEMINATION

The underlying study is based on published articles thus does not require ethical approval. The findings of the systematic review and meta-analysis will be published in a peer-reviewed journal and disseminated in various scientific conferences and seminars.

PROSPERO REGISTRATION NUMBER

CRD42022373321.

Diagnostic performance of the IMMY cryptococcal antigen lateral flow assay on serum and cerebrospinal fluid for diagnosis of cryptococcosis in HIV-negative patients: a systematic review

BACKGROUND

The incidence of cryptococcosis amongst HIV-negative persons is increasing. Whilst the excellent performance of the CrAg testing in people living with HIV is well described, the diagnostic performance of the CrAg LFA has not been systematically evaluated in HIV-negative cohorts on serum or cerebrospinal fluid.

METHODS

We performed a systematic review to characterise the diagnostic performance of IMMY CrAg® LFA in HIV-negative populations on serum and cerebrospinal fluid. A systematic electronic search was performed using Medline, Embase, Global Health, CENTRAL, WoS Science Citation Index, SCOPUS, Africa-Wide Information, LILACS and WHO Global Health Library. Studies were screened and data extracted from eligible studies by two independent reviewers. A fixed effect meta-analysis was used to estimate the diagnostic sensitivity and specificity.

RESULTS

Of 447 records assessed for eligibility, nine studies met our inclusion criteria, including 528 participants overall. Amongst eight studies that evaluated the diagnostic performance of the IMMY CrAg® LFA on serum, the pooled median sensitivity was 96% (95% Credible Interval (CrI) 68-100%) with a pooled specificity estimate of 96% (95%CrI 84-100%). Amongst six studies which evaluated the diagnostic performance of IMMY CrAg® LFA on CSF, the pooled median sensitivity was 99% (95%CrI 95-100%) with a pooled specificity median of 99% (95%CrI 95-100%).

CONCLUSIONS

This review demonstrates a high pooled sensitivity and specificity for the IMMY CrAg® LFA in HIV-negative populations, in keeping with findings in HIV-positive individuals. The review was limited by the small number of studies. Further studies using IMMY CrAg® LFA in HIV-negative populations would help to better determine the diagnostic value of this test.

How to use biomarkers of infection or sepsis at the bedside: guide to clinicians

Sepsis is defined as a life-threatening organ dysfunction caused by a dysregulated host response to infection. In this context, biomarkers could be considered as indicators of either infection or dysregulated host response or response to treatment and/or aid clinicians to prognosticate patient risk. More than 250 biomarkers have been identified and evaluated over the last few decades, but no biomarker accurately differentiates between sepsis and sepsis-like syndrome. Published data support the use of biomarkers for pathogen identification, clinical diagnosis, and optimization of antibiotic treatment. In this narrative review, we highlight how clinicians could improve the use of pathogen-specific and of the most used host-response biomarkers, procalcitonin and C-reactive protein, to improve the clinical care of patients with sepsis. Biomarker kinetics are more useful than single values in predicting sepsis, when making the diagnosis and assessing the response to antibiotic therapy. Finally, integrated biomarker-guided algorithms may hold promise to improve both the diagnosis and prognosis of sepsis. Herein, we provide current data on the clinical utility of pathogen-specific and host-response biomarkers, offer guidance on how to optimize their use, and propose the needs for future research.

An Alternative Diagnostic Method for C. neoformans: Preliminary Results of Deep-Learning Based Detection Model

Cryptococcus neoformans is an opportunistic fungal pathogen with significant medical importance, especially in immunosuppressed patients. It is the causative agent of cryptococcosis. An estimated 220,000 annual cases of cryptococcal meningitis (CM) occur among people with HIV/AIDS globally, resulting in nearly 181,000 deaths. The gold standards for the diagnosis are either direct microscopic identification or fungal cultures. However, these diagnostic methods need special types of equipment and clinical expertise, and relatively low sensitivities have also been reported. This study aims to produce and implement a deep-learning approach to detect C. neoformans in patient samples. Therefore, we adopted the state-of-the-art VGG16 model, which determines the output information from a single image. Images that contain C. neoformans are designated positive, while others are designated negative throughout this section. Model training, validation, testing, and evaluation were conducted using frameworks and libraries. The state-of-the-art VGG16 model produced an accuracy and loss of 86.88% and 0.36203, respectively. Results prove that the deep learning framework VGG16 can be helpful as an alternative diagnostic method for the rapid and accurate identification of the C. neoformans, leading to early diagnosis and subsequent treatment. Further studies should include more and higher quality images to eliminate the limitations of the adopted deep learning model.

The Use of Host Biomarkers for the Management of Invasive Fungal Disease

Invasive fungal disease (IFD) causes severe morbidity and mortality, and the number of IFD cases is increasing. Exposure to opportunistic fungal pathogens is inevitable, but not all patients with underlying diseases increasing susceptibility to IFD, develop it. IFD diagnosis currently uses fungal biomarkers and clinical risk/presentation to stratify high-risk patients and classifies them into possible, probable, and proven IFD. However, the fungal species responsible for IFD are highly diverse and present numerous diagnostic challenges, which culminates in the empirical anti-fungal treatment of patients at risk of IFD. Recent studies have focussed on host-derived biomarkers that may mediate IFD risk and can be used to predict, and even identify IFD. The identification of novel host genetic variants, host gene expression changes, and host protein expression (cytokines and chemokines) associated with increased risk of IFD has enhanced our understanding of why only some patients at risk of IFD actually develop disease. Furthermore, these host biomarkers when incorporated into predictive models alongside conventional diagnostic techniques enhance predictive and diagnostic results. Once validated in larger studies, host biomarkers associated with IFD may optimize the clinical management of populations at risk of IFD. This review will summarise the latest developments in the identification of host biomarkers for IFD, their use in predictive modelling and their potential application/usefulness for informing clinical decisions.

The importance of antimicrobial resistance in medical mycology

Prior to the SARS-CoV-2 pandemic, antibiotic resistance was listed as the major global health care priority. Some analyses, including the O'Neill report, have predicted that deaths due to drug-resistant bacterial infections may eclipse the total number of cancer deaths by 2050. Although fungal infections remain in the shadow of public awareness, total attributable annual deaths are similar to, or exceeds, global mortalities due to malaria, tuberculosis or HIV. The impact of fungal infections has been exacerbated by the steady rise of antifungal drug resistant strains and species which reflects the widespread use of antifungals for prophylaxis and therapy, and in the case of azole resistance in Aspergillus, has been linked to the widespread agricultural use of antifungals. This review, based on a workshop hosted by the Medical Research Council and the University of Exeter, illuminates the problem of antifungal resistance and suggests how this growing threat might be mitigated.

Interpretation, pitfalls of biomarkers in diagnosis of invasive fungal diseases

BACKGROUND

Invasive Fungal Diseases (IFD), account for high morbidity and mortality in immunocompromised and seriously ill patients worldwide. Early, faster and accurate diagnosis with timely and appropriate patient management is critical for improved patient outcome and antifungal stewardship. Clinical/radiological presentations in IFD are non-specific and microscopy/culture based tests have low sensitivity and long turnaround time. Biomarkers have clinical utility for diagnosing IFD but their interpretation is not straight forward.

OBJECTIVES

This review discusses the salient characteristics, clinical usefulness and limitations of common biomarkers such as Galactomannan (GM), 1-3, β D glucan (βDG), mannan, anti-mannan antibody (Mn/antiMn), Cryptococcal antigen test (CrAg), Nucleic Acid Amplification (NAA) tests and next generation sequencing for diagnosing IFD.

CONTENTS

Fungal biomarkers are useful adjuncts as screening and diagnostic tools for IFD and are much more suited for 'ruling out' rather than 'ruling in' disease. GM, NAA tests are promising biomarkers for screening of invasive Aspergillosis in high risk asymptomatic patients who are not on antifungal therapy and for diagnosis of breakthrough infections in symptomatic patients. 1-3, β D glucan has limitations both as a 'rule in' and 'rule out' test and is useful in only specific clinical settings. Two consecutive positive 1-3-βDG tests or combined positivity with GM increases its specificity. Mn/antiMn, T2Candida nano diagnostic panel are promising candidates for diagnosing invasive candidiasis. Combining two or more biomarkers improves the sensitivity for prompt initiation of antifungal therapy and the negative predictive value for suspension of empirical treatment. Serum CrAg test is a good 'rule in' rather than a 'rule out' test in immunocompetent patients but has good diagnostic accuracy in immunocompromised patients. Detection of single nucleotide polymorphisms by next generation sequencing is useful for fungal characterization and identification of host determinants responsible for increased susceptibility to fungal infections but is still in experimental stages.

Clinical Characteristics and Risk Factors for Mortality in Cryptococcal Meningitis: Evidence From a Cohort Study

Introduction

Despite advances in the diagnosis and management, cryptococcal meningitis (CM) is still associated with high mortality due to insufficient knowledge about clinical characteristics and risk factors for poor outcomes. The aim of the present study is to provide additional evidence for regarding clinical characteristics, diagnosis, and factors associated with increased risk of mortality in CM patients.

Methods

In this cohort study, we included eligible patients consecutively admitted to West China Hospital between January 2009 and December 2018. The clinical characteristics and diagnosis method of cerebrospinal fluid culture and India ink stain were analyzed. Independent risk factors were identified by a multivariable logistic regression.

Results

A total of 186 CM patients were included in the analysis. After a 1-year follow-up, 63 patients had died. Headache is the most common presenting symptom (97.3%), followed by vomiting (72%), fever (71.5%), altered consciousness (45.7%), abnormal vision (32.8%), and seizure (15.1%). Older age, altered consciousness or seizures, lower white blood cell count or total protein in cerebrospinal fluid (CSF), and unidentified CSF cryptococcal antigen (CrAg) are all factors associated with increasing risk of death (P < 0.05). We also found a dose-dependent trend between the number of symptoms and risk of death (trend p < 0.001). Multivariate logistic regression revealed that age (P = 0.004, OR = 1.042, 95% CI 1.013–1.071), seizure (P = 0.025, OR = 3.105, 95% CI 1.152–8.369), altered consciousness (P < 0.001, OR=6.858, 95% CI 3.063–15.38), and unidentified CSF CrAg are the independent prognostic factors. In addition, we observed that diagnosis of 28.5% and 22.5% CM could not be established by a single testing of CSF India ink stain or culture, respectively. Use of multiple testing methods or combination of the two assays increases the detection rate.

Conclusion

Our data show that older age, seizures, altered consciousness, and an inability to detect CSF CrAg are the independent risk factors of death within 1 year in CM patients. Moreover, we recommend use of multiple testing methods with CSF culture and India ink stain. Combined testing with both assays should be considered for initial CM diagnosis.

Diagnosis of invasive fungal disease in coronavirus disease 2019: approaches and pitfalls

PURPOSE OF REVIEW

This review will comment on the current knowledge for the diagnosis of the main causes of COVID-19-associated invasive fungal disease (IFD); it will discuss the optimal strategies and limitations and wherever available, will describe international recommendations.

RECENT FINDINGS

A range of secondary IFDs complicating COVID-19 infection have been described and while COVID-19-associated pulmonary aspergillosis was predicted, the presentation of significant numbers of COVID-19-associated candidosis and COVID-19-associated mucormycosis was somewhat unexpected. Given the range of IFDs and prolonged duration of risk, diagnostic strategies need to involve multiple tests for detecting and differentiating various causes of IFD. Although performance data for a range of tests to diagnose COVID-19-associated pulmonary aspergillosis is emerging, the performance of tests to diagnose other IFD is unknown or based on pre-COVID performance data.

SUMMARY

Because of the vast numbers of COVID-19 infections, IFD in COVID-19 critical-care patients represents a significant burden of disease, even if incidences are less than 5%. Optimal diagnosis of COVID-19-associated IFD requires a strategic approach. The pandemic has highlighted the potential impact of IFD outside of the typical high-risk clinical cohorts, given the ever-increasing population at risk of IFD and enhanced surveillance of fungal infections is required.

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.

Symptomatic Cryptococcal Meningitis with Negative Serum and Cerebrospinal Fluid Cryptococcal Antigen Tests

Background

Cryptococcal meningitis is a leading cause of mortality in advanced HIV disease. A positive cerebrospinal fluid cryptococcal antigen (CrAg) test defines cryptococcal meningitis. Herein, we present a patient with serum and cerebrospinal fluid CrAg negative cryptococcal meningitis, despite a positive cerebrospinal fluid India ink examination and quantitative culture.

Case Details

A 56-year-old HIV-positive Ugandan woman, with an undetectable HIV RNA viral load and CD4+ T-cell count of 766 cells per microlitre presented with signs and symptoms consistent with cryptococcal meningitis. Her serum and cerebrospinal fluid CrAg tests were negative despite having a positive cerebrospinal fluid India ink and quantitative culture. On day 1, she was commenced on intravenous amphotericin B deoxycholate (1mg/kg) for 3 days (considering 10 CFU growth of Cryptococcus spp) in combination with oral flucytosine (100mg/kg) for 7 days and then fluconazole 1200mg once daily for the next 11 days. By day 7, she was symptom free and quantitative cerebrospinal fluid culture was negative for Cryptococcus spp. She was discharged on day 9. At 10 weeks (day +40) and 18 weeks (day +72), she was well and adherent to her antiretroviral therapy and on maintenance phase of cryptococcal meningitis on fluconazole at a dose of 400mg once daily.

Conclusion

This report alerts clinicians managing patients with HIV-associated cryptococcal meningitis to four uncommon clinical scenarios; first, the possibility of negative serum and cerebrospinal fluid CrAg lateral flow assay results in the context of low cerebrospinal fluid fungal burden in a symptomatic patient. Second, possible occurrence of cryptococcal meningitis in a patient with high CD4 T-cell lymphocyte counts. Third, an early seroconversion of cryptococcal antigenaemia following effective fluconazole therapy. Fourth, an early symptomatic relapse of cryptococcal meningitis albeit negative serum CrAg.

Differences in cytokine and chemokine profiles in cerebrospinal fluid caused by the etiology of cryptococcal meningitis and tuberculous meningitis in HIV patients

The roles of cytokines and chemokines in HIV-associated cryptococcal meningitis (HCM) and HIV-associated tuberculous meningitis (HTBM) are debatable. In sum, 34 HIV-infected patients without meningitis, 44 HCM patients and 27 HTBM patients were enrolled for study. The concentrations of 22 cytokines/chemokines in cerebrospinal fluid (CSF) were assayed at admission. Principal component analysis (PCA), Pearson's and logistic regression analyses were used to assess the role of cytokines/chemokines in HCM and HTBM. We found the levels of T helper (Th)17, Th1 [interleukin (IL)-12p40, interferon (IFN)-γ, tumor necrosis factor (TNF)-α and TNF-β and Th2 (IL-2/4/5/6/10)] cytokines were elevated in patients with meningitis compared with those in HIV-infected patients without central nervous system (CNS) infection. Furthermore, the IL-1Ra, IL-12p40, IL-17α and monocyte chemotactic protein-1 (MCP-1) levels were higher in HCM patients, while the IFN-γ, regulated upon activation, normal T cell expressed and secreted (RANTES) and interferon-inducible protein-10 (IP)-10 levels were higher in HTBM patients. Elevated CSF concentrations of IL-17a, TNF-β, IL-5, IL-12p40 and IL-1Rα were closely related to meningitis, but elevated IP-10, MCP-1, RANTES and IFN-γ levels and CSF white blood cells (WBCs) were protective factors against HCM. Our study suggested that HIV-infected patients with low CSF WBCs have a high risk of HCM. Th1, Th2 and Th17 cytokines/chemokines mediate differences in the pathogenesis of HCM and TBM. Overexpressed proinflammatory MCP-1, RANTES, IFN-γ and IP-10 in CSF are protective factors against HCM but not HTBM.

Cost-effectiveness analysis and budgetary impact of the Cryptococcal Antigen Lateral Flow Assay (CRAG-LFA) implementation for the screening and diagnosis of cryptococcosis in asymptomatic people living with HIV in Brazil

Cryptococcal infection is a frequent cause of mortality in Brazilian HIV-infected patients. The present study aimed to evaluate the cost-effectiveness and budgetary impact of four cryptococcosis screening strategies in HIV-infected patients with CD4+ ≤ 200 cells/mm³, in Brazil. A Monte Carlo microsimulation was used to compare the following diagnostic tests: a systematic serum cryptococcal antigen (CRAG) screening with latex agglutination (CRAG-LA), a lateral flow immunochromatographic test (CRAG-LFA), India ink staining and no intervention. The rationale was that of the Unified Health System (SUS), and the time horizon was of one year for the intervention and of five years for the budgetary impact analysis (BIA). The effectiveness outcomes were years of life and years of life adjusted for quality (QALY). The cost-effectiveness analysis showed that the two cryptococcal antigen tests were cost-effective, presenting with superior results in comparison with India ink and no screening. CRAG-LFA, compared to CRAG-LA, has an incremental cost of US$0.25 and an incremental cost-effectiveness ratio of US$73.36 (considering the US dollar equal to 5 reais, the Brazilian current money). The probabilistic sensitivity analysis between CRAG-LFA and CRAG-LA, despite showing a high agreement between the two tests, indicated the superiority of CRAG-LFA. The BIA estimated that the incorporation of CRAG-LFA would have an additional cost of approximately U$S 10.4 million dollars in five years. These findings suggest that, for the group of studied patients, the adoption of CRAG-LFA and CRAG-LA are cost-effective, while the India ink test and no intervention are less effective strategies. The BIA showed that using the CRAG-LFA test for people living with HIV (PLHIV) with CD4+ ≤ 200 cells/mm³ could reduce costs for the Brazilian Unified Health System (SUS).

Update on Pulmonary Cryptococcosis

Pulmonary cryptococcosis is a common but underdiagnosed opportunistic fungal infection in both immunocompromised and immunocompetent patients. The causal agents include at least eight evolutionary distinct haploid lineages as well as their hybrids of the human pathogenic Cryptococcus complex. In this update, we review recent advances in epidemiology, mode of transmission, risk factors, diagnostic methods, and therapy of pulmonary cryptococcosis. Our review suggests significant challenges and opportunities for research, from bedside to benchside and back to bedside.

Implementation of rapid diagnostics assays for detection of histoplasmosis and cryptococcosis in central american people living with HIV

Objectives

Histoplasmosis and cryptococcosis are important public health problems in people living with HIV (PLHIV) in Central America. Conventional laboratory assays, based on microscopy and culture, are not optimal for the diagnosis of either disease. However, antigen (Ag) assays are rapid and highly accurate for the diagnosis of these infections.

Methods

Laboratory surveillance of PLHIV was carried out in four hospitals in Panama, Honduras and Nicaragua, between 2015 and 2019. Detection of Histoplasma antigens in urine was performed by enzyme immunoassay (EIA), and Cryptococcus antigen detection in sera and cerebrospinal fluid specimens was performed by lateral flow assay (LFA).

Results

A total of 4,453 PLHIV with clinical suspicion of histoplasmosis (n = 1,343) or cryptococcosis (n = 3,110; 2,721 sera and 389 CSF) were tested. Of 1,343 patients suspected of having histoplasmosis, 269 (20%) were Histoplasma Ag positive. Of 3,110 patients tested using the Cryptococcus Ag assay, 329 (11%) were positive. Honduras reported the highest positivity rates (32% for Histoplasma Ag, and 16% for Cryptococcus Ag); Panama reported the largest number of patients testing positive using the Histoplasma Ag assay (n = 201); and Nicaragua reported the largest number of patients testing positive using the Cryptococcus Ag assay (n = 170).

Conclusion

Here, we show how the implementation of rapid diagnostics assays impacted case detection and was useful for the care of people with advanced HIV. Rapid and accurate diagnosis could reduce mortality associated with histoplasmosis and cryptococcosis in PLHIV.

Efficacy of induction regimens for cryptococcal meningitis in HIV-infected adults: a systematic review and network meta-analysis

Cryptococcal meningitis (CM) is the most fatal adult meningitis in patients with human immunodeficiency virus (HIV). There is no conclusive evidence for the superiority of 1-week amphotericin B deoxycholate (AmphB) + flucytosine (5-FC) regimen over other antifungals in the management of HIV patients with CM (HIV-CM patients). We aimed to evaluate the differences in efficacy and tolerability of different antifungal agents in HIV-CM patients by conducting a current network meta-analysis NMA. Overall, 19 randomized controlled trials were included with 2642 participants. A regimen indicated a possibly lower early mortality rate, namely, AmphB + 5-FC + Azole (OR = 1.1E-12, 95% CIs = 1.3E-41 to 0.06) comparing to AmphB + 5-FC. The current NMA provides evidence that AmphB + 5-FC + Azole are superior to all the investigated treatments for induction regimen in HIV-CM patients.

Associations between Cryptococcus Genotypes, Phenotypes, and Clinical Parameters of Human Disease: A Review

The genus Cryptococcus contains two primary species complexes that are significant opportunistic human fungal pathogens: C. neoformans and C. gattii. In humans, cryptococcosis can manifest in many ways, but most often results in either pulmonary or central nervous system disease. Patients with cryptococcosis can display a variety of symptoms on a spectrum of severity because of the interaction between yeast and host. The bulk of our knowledge regarding Cryptococcus and the mechanisms of disease stem from in vitro experiments and in vivo animal models that make a fair attempt, but do not recapitulate the conditions inside the human host. To better understand the dynamics of initiation and progression in cryptococcal disease, it is important to study the genetic and phenotypic differences in the context of human infection to identify the human and fungal risk factors that contribute to pathogenesis and poor clinical outcomes. In this review, we summarize the current understanding of the different clinical presentations and health outcomes that are associated with pathogenicity and virulence of cryptococcal strains with respect to specific genotypes and phenotypes.