Cryptococcal Infection Research Articles

Cryptococcosis in non-HIV/non-transplant hematological patients: A 12-year retrospective clinical analysis in a Peruvian referral cancer center.

e19536 Background: Globally, cryptococcal infection has become a public health challenge. However, relatively little is known about cryptococcal infection in non-HIV/non-transplant oncohematological patients. Methods: We developed a retrospective cohort study that includes hematological patients who had cryptococcosis infection seen in the Instituto Nacional de Enfermedades Neoplasicas between 2007 and 2018. We exclude HIV and transplant recipients patients. Results: During the 12-year study period, among 14908 individuals with hematological malignancies (HM), a total of 21 cases of cryptococcosis were identified, representing an incidence rate of 1.41 per 1000 HM diagnosed in our center. Non-Hodgkin lymphoma (NHL) (47.6%), acute leukemias (23.8%), multiple myeloma (19.1%), and Hodgkin lymphoma (9.5%). Three cases of adult T-cell leukemia/lymphoma were identified. The sub-group analysis showed that NHL (7.35 per 1000 NHL) and Multiple myeloma (4.59 per 1000 MM) had the highest incidence rates. Regarding the clinical presentation, the time between the diagnosis of cryptococcosis and HM was 42 (18–161) days. Cryptococcal fungemia and antigenemia was the most frequent diagnosis (85.7%), followed by pulmonary (52.4%) and central nervous system (38.1%) involvement. At the time of the diagnosis of cryptococcosis, 61.5% were receiving chemotherapy, 53.9% were in the induction phase, and 7.7% were on maintenance therapy. The use of immunosuppressants and chemotherapy within a month of the diagnosis of cryptococcosis was the most common risk factor (90.5%). Regarding the subanalysis performed between the different types of malignancies (NHL versus other HM), age at admission (p = 0.02), site of cryptococcosis presentation (p = 0.01), and lymphocyte count at admission (p = 0.01) were statistically different between these groups. In the NHL subgroup, there was less involvement of the lungs and higher fungemia (p = 0.01). The overall survival (OS) of our cohort at 15 and 120 days was 70% (95%CI: 0.43-0.86) and 51% (95%CI: 0.26-0.72), respectively. OS for patients with NHL was 57% at 15 days (95% CI: 0.17-0.83) and 42% at 120 days (95%CI:0.09-0.73). OS for other HM was 90% at 15 days (95%CI:0.47-0.98) and 60% at 120 days (95%CI: 0.25-0.82). Conclusions: Our cohort characterized the distinct clinical presentation, risk factors, and outcomes of cryptococcal infection in hematologic malignancies subgroups. NHL was the HM with the worst prognosis and the highest incidence rate. [Table: see text]

Innate Pulmonary Phagocytes and Their Interactions with Pathogenic Cryptococcus Species.

Cryptococcus neoformans is an opportunistic fungal pathogen that causes over 180,000 annual deaths in HIV/AIDS patients. Innate phagocytes in the lungs, such as dendritic cells (DCs) and macrophages, are the first cells to interact with the pathogen. Neutrophils, another innate phagocyte, are recruited to the lungs during cryptococcal infection. These innate cells are involved in early detection of C. neoformans, as well as the removal and clearance of cryptococcal infections. However, C. neoformans has developed ways to interfere with these processes, allowing for the evasion of the host's innate immune system. Additionally, the innate immune cells have the ability to aid in cryptococcal pathogenesis. This review discusses recent literature on the interactions of innate pulmonary phagocytes with C. neoformans.

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.

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. 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. 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). 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.

Yeast–amoeba interaction influences murine cryptococcosis

The virulence of Cryptococcus spp. is modulated in the natural environment through interaction with abiotic and biotic factors, and this can occasionally have implications for the progression of cryptococcosis in mammals. Hence, we evaluated whether the prior interaction of highly virulent Cryptococcus gattii strain R265 with Acanthamoeba castellanii influenced the progression of cryptococcosis. The influence of the capsule on endocytosis was evaluated using amoeba and yeast morphometrics. Mice were intratracheally infected with yeast re-isolated from the amoeba (Interaction), yeast without prior contact with the amoeba (Non-Interaction), or sterile phosphate-buffered saline (SHAM). Morbidity signs and symptoms were monitored during the survival curve, while cytokine and fungal burden measurements and histopathological analysis were performed on the 10th day post infection. Morbidity and mortality parameters in experimental cryptococcosis were influenced by the prior interaction of yeast with amoeba, which led to phenotypic changes in the cryptococcal cells, polysaccharide secretion, and their tolerance to oxidative stress. Our results suggest that a prior yeast–amoeba interaction modulates yeast virulence, which is associated with a greater tolerance to oxidative stress related to the exo-polysaccharide content and influences the progression of cryptococcal infection.

Methods for Antifungal Susceptibility Testing of the Cryptococcus neoformans/C. gattii Complex: Strengths and Limitations

When method-dependent categorical endpoints are available, namely either BPs or ECVs, MICs could aid in selecting the best treatment agent(s). BPs can categorize an isolate as either susceptible or resistant while the ECVs/ECOFFs can distinguish the wild type (WT, no known resistance mechanisms) from the Non-WT (NWT, harboring resistant mechanisms). Our literature review focused on the Cryptococcus species complex (SC) and the available methods and categorization endpoints. We also covered the incidence of these infections as well as the numerous Cryptococcus neoformans SC and C. gattii SC genotypes. The most important agents to treat cryptococcal infections are fluconazole (widely used), amphotericin B, and flucytosine. We provide data from the collaborative study that defined CLSI fluconazole ECVs for the most common cryptococcal species or genotypes and modes. EUCAST ECVs/ECOFFs are not yet available for fluconazole. We have summarized the incidence of cryptococccal infections (2000-2015) where fluconazole MICs were obtained by reference and commercial antifungal susceptibility tests. This occurrence is documented all over the world and those fluconazole MICs are mostly categorized by available CLSI ECVs/BPs as "resistant" instead of non-susceptible strains, including those by the commercial methods. As expected, the agreement between the CLSI and commercial methods is variable because SYO and Etest data could yield low/variable agreement (<90%) versus the CLSI method. Therefore, since BPs/ECVs are species and method dependent, why not gather sufficient MICs by commercial methods and define the required ECVs for these species?

Cryptococcosis Inhibits the Immune Response of Dendritic Cells Through the snhg1-miR-145a-3p-Bcl2 Axis.

Dendritic cells are one of the first host cells that cryptococcus encounters. However, the correlations among cryptococcus, dendritic cells, and long noncoding RNA remain unclear. This study was undertaken to investigate the effects of long noncoding RNAs on dendritic cells with cryptococcus infection. We treated dendritic cells with cryptococcus and then detected expression of CD80, CD86, and major histocompatibility complex class II in dendritic cells with a real-time fluorescent quantitative polymerase chain reaction assay. We used nextgeneration sequencing and bioinformatics analysis to determine the competitive endogenous RNA mechanisms, confirmed via real-time polymerase chain reaction, dual luciferase reporter, and RNA-binding protein immunoprecipitation assays. After treatment of dendritic cells with 1 × 108 CFU/mL cryptococcus for 12 hours, dendritic cell viability was normal, whereas mRNA expression levels of CD80, CD86, and major histocompatibility complex class II in dendritic cells were substantially increased. With next-generation sequencing, we discovered 4 small nucleolar RNA host genes (snhg1, snhg3, snhg4, and snhg16) in cryptococcus-treated dendritic cells compared with wild-type dendritic cells. Bioinformatics analysis combined with real-time polymerase chain reaction led us to speculate that cryptococcus may affect the maturation and apoptosis of dendritic cells by regulating snhg1-miR-145a-3p-Bcl2. Further polymerase chain reaction, dual luciferase reporter, and RNA-binding protein immunoprecipitation experiments revealed that snhg1 acted as a sponge for miR145a-3p to inhibit the expression of miR-145a-3p and that miR-145a-3p promoted the expression of Bcl2 by directly targeting the 3'-UTR of Bcl2. Functional recovery experiments showed that cryptococcus promoted the maturation and apoptosis and inhibited the proliferation of dendritic cells through the snhg1-Bcl2 pathway. This study lays a foundation for the further understanding of the pathogenic role of snhg1-miR-145a-3p-Bcl2 axis in cryptococcosis.

Successful Treatment with High-Dose Immunoglobulin of a Complicated Patient with Catatonia and Central Nervous System Autoantibodies

Ms. X is a 52-year-old Filipino female with no prior psychiatric or medical history who initially presented to an outside hospital for new onset headache, neck pain, and altered mental status. She was admitted inpatient medicine service and was found to have HIV/AIDs and cryptococcal meningoencephalitis. Ms. X had a good response to appropriate antifungal therapies and was able to discharge home with full resolution of symptoms on high dose fluconozaole. Unfortunately, Ms. X developed transaminitis on high dose fluconazole, the dose was reduced and she presented to our institution with recurrent cryptococcal meningoencephalitis as evidenced by elevated titers of cryptococcal antigen in CSF and MRI studies showing T2 and FLAIR hyperintensities in bilateral basal ganglia, thalamus and medial temporal lobes and evidence of intracranial hypertension. Consequently, Ms. X developed prominent neuropsychiatric symptoms including agitation, cognitive impairment, paranoia, visual hallucinations and symptoms of catatonia. Despite adequate treatment of the cryptococcal infection evidenced by decreasing cryptococcal antigen titers in CSF, and appropriate psychiatric treatment, her neuropsychiatric symptoms persisted and her MRI studies continued to show signs of neuroinflammation in the aforementioned areas. Antibody testing for basal ganglia targets was completed to investigate a possible non-infectious cause of neuroinflammation and neuropsychiatric symptoms. Ms. X was found to have elevated titers of anti-D1, anti-GM1 and anti-tubulin receptor antibodies in her CSF. Due to the severity and treatment resistant nature of her neuropsychiatric symptoms, she was treated with 2 g/kg/day IVIG for 4 days. She showed significant improvement in her neuropsychiatric symptoms after 3 days and full resolution of her neuropsychiatric symptoms 1 week following IVIG. Given remarkable clinical response to IVIG a second round of IVIG was administered 2 weeks later in order to sustain the response. After several months of prolonged hospitalization, Ms X was able to discharge to the care of her family and to date her neuropsychiatric symptoms remain in remission. We propose Ms. X’s persistent, treatment resistant neuropsychiatric symptoms were related to a post-infectious inflammatory encephalopathy that responded robustly to IVIG.

Glucuronoxylomannan intranasal challenge prior to Cryptococcus neoformans pulmonary infection enhances cerebral cryptococcosis in rodents

The encapsulated fungus Cryptococcus neoformans is the most common cause of fungal meningitis, with the highest rate of disease in patients with AIDS or immunosuppression. This microbe enters the human body via inhalation of infectious particles. C. neoformans capsular polysaccharide, in which the major component is glucuronoxylomannan (GXM), extensively accumulates in tissues and compromises host immune responses. C. neoformans travels from the lungs to the bloodstream and crosses to the brain via transcytosis, paracytosis, or inside of phagocytes using a "Trojan horse" mechanism. The fungus causes life-threatening meningoencephalitis with high mortality rates. Hence, we investigated the impact of intranasal exogenous GXM administration on C. neoformans infection in C57BL/6 mice. GXM enhances cryptococcal pulmonary infection and facilitates fungal systemic dissemination and brain invasion. Pre-challenge of GXM results in detection of the polysaccharide in lungs, serum, and surprisingly brain, the latter likely reached through the nasal cavity. GXM significantly alters endothelial cell tight junction protein expression in vivo, suggesting significant implications for the C. neoformans mechanisms of brain invasion. Using a microtiter transwell system, we showed that GXM disrupts the trans-endothelial electrical resistance, weakening human brain endothelial cell monolayers co-cultured with pericytes, supportive cells of blood vessels/capillaries found in the blood-brain barrier (BBB) to promote C. neoformans BBB penetration. Our findings should be considered in the development of therapeutics to combat the devastating complications of cryptococcosis that results in an estimated ~200,000 deaths worldwide each year.

Herpes Simplex Virus (HSV), Varicella-Zoster Virus (VZV), and Cryptococcal Infections Associated With Sphingosine-1-Phosphate Receptor (S1PR) Modulators: A Review (P12-10.005)

<h3>Objective:</h3> To summarize the existing data on the incidence of herpes simplex virus (HSV), varicella-zoster virus (VZV), and Cryptococcus sp. infections with sphingosine-1-phosphate receptor (S1PR) modulators. <h3>Background:</h3> S1PR modulators are a novel class of disease-modifying therapies for multiple sclerosis (MS) that produce immunosuppression and potential lymphopenia. Herpesvirus and cryptococcal diseases were the most common opportunistic infections in clinical trials. Several post-hoc analyses have subsequently been published with revised incidence rates (IRs) for these conditions. <h3>Design/Methods:</h3> A literature review and descriptive analysis of phase-3 trials (n=6), post-marketing studies (n=8), and case reports (n=17) were conducted using PubMed and Google Scholar. Further data was accessed through Novartis AG, Bristol-Myers Squibb, and Janssen Pharmaceuticals. <h3>Results:</h3> <h3>FINGOLIMOD:</h3> Herpesvirus infection rates were similar between placebo (2.8%) and 0.5 mg (2.1%) but increased with 1.25 mg (5.5%) in the TRANSFORMS study. VZV rates were higher with fingolimod 0.5 mg (3.0%; 11 per 1000 patient-years [PY]) than with placebo (1.0%; 6 per 1000 PY), but comparable post-marketing. Cryptococcal infections (n=74) had an IR of 9 per 100,000 PY, and 13 cases were individually reported. <h3>SIPONIMOD:</h3> VZV reactivation occurred more frequently with siponimod (2%) than with placebo (1%); EXPAND extension analyses calculated an IR of 0.9 for HSV and 1.8 for VZV infections. One case of cryptococcal meningitis (from 7236 PY of exposure) was documented. <h3>OZANIMOD:</h3> An integrated safety analysis reported oral herpes at 1.5%, VZV at 1.4%, and HSV at 0.5% from all clinical trials versus 0.7%, 0.6%, and 0.1% from the phase-3 trials. The IR of herpes zoster was 5.3/1000 PY. <h3>PONESIMOD:</h3> The incidence of herpetic infections was equal between both groups (4.8%) in the OPTIMUM trial. Cryptococcal infections have not yet been reported with ozanimod or ponesimod. <h3>Conclusions:</h3> Overall, the incidence of these opportunistic infections associated with S1PR modulators in MS was low, with favorable outcomes and limited fatalities. <b>Disclosure:</b> Dr. Sharma has nothing to disclose. Mr. JHA has nothing to disclose. Dr. Khanal has nothing to disclose. Dr. Sriwastava has nothing to disclose.

Tetrahydrocurcumin (THC) enhanced the clearance of Cryptococcus deneoformans during infection in vivo

Cryptococcal species often cause lung infections and are the main cause of fungal meningitis. Claudin-4 appears to be a major structural component that maintains a tight alveolar barrier and prevents fluid and electrolyte leakage into the alveolar space. We aimed to determine whether S7-tetrahydrocurcumin (THC) could clearance of C. deneoformans and regulate claudin-4 expression during C. deneoformans infection. We investigated the effect of THC on C. deneoformans infection and its possible mechanism in vivo. Transmission electron microscopy was used to observe the ultrastructure of the lung tissue and the invasion of Cryptococcus. To clarify the effect of THC, we examined claudin-4, c-Jun, and Smad2 expression. We also measured claudin-4 expression in pulmonary specimens from clinical patients. THC reduced cryptococcal cell invasion in the lungs, improved alveolar exudation, and reduced inflammation. Pretreatment with THC suppressed c-Jun and Smad2 expression, resulting in significantly increased claudin-4 levels. In contrast, the expression of claudin-4 in clinical specimens from patients with cryptococcal infection was higher than that in normal specimens. THC enhanced the clearance of C. deneoformans during infection in vivo. We investigated the expression of claudin-4 and the possible mechanism of THC against C. deneoformans infection.

A Case of Brainstem Cryptococcoma Causing Pontine Stroke in an Immunocompetent Male (P1-10.003)

<h3>Objective:</h3> N/A <h3>Background:</h3> Cryptococcus is an invasive fungal disease seen in immune compromised individuals and usually present as meningitis when involved in the Central Nervous System. Cerebral cryptococcoma is a rare form of cryptococcal infection which is often misdiagnosed. Literature reviews showed most of them are located in frontal lobe, parietal lobe or basal ganglia. The involvement of pons only has been extremely rare. There are cases of cryptococcal meningitis causing ischemic stroke due to vasculitis but this case was complicated by perforator infarct adjacent to the lesion. <h3>Design/Methods:</h3> N/A <h3>Results:</h3> <h3>Case presentation:</h3> We are going to discuss a 58 years old immunocompetent male who initially presented with dizziness and double vision. MRI of brain showed small acute infarct in right paramedian pons with adjacent edema out of proportion to the infarct. The contrast showed ring enhancing lesion. The patient returned after 4 months with severe headache and double vision. Repeat MRI of brain showed slightly enlarged ring enhancing lesion in right ventral pons. CSF study was positive for Cryptococcus neoformans both times. <h3>Conclusions:</h3> Diagnosis of cryptococcoma is often challenging especially in immunocompetent individuals where the clinical suspicion is low. There have been case reports where it has been misdiagnosed as neoplasm, tumefactive demyelinating disease and stroke. Therefore, causing delays in treatment leading to increased mortality and morbidity. This discussion indicates that physicians should have low threshold to suspect cryptococcoma in immunocompetent individual with ring enhancing lesion as timely intervention can save lives from this invasive fungal disease. <b>Disclosure:</b> Dr. Jabeen has nothing to disclose. Dr. Maghsoudlou has nothing to disclose.

PROLONGED FEVER ETIOLOGIES IN HIV/AIDS PATIENTS AND THE RELATION WITH TCD4 COUNT (1/2016 - 6/2019)

Objectives: Prolonged fever is a challenge for clinician in managing patients with HIV/AIDS. Their TCD4 counts can be helpful in the diagnosis and treatment. Our goal was to determinethe most common etiologies of prolonged fever and their distribution in different TCD4 count levels in HIV/AIDS patients. &#x0D; Subjects and method: A cross - sectional descriptive study was conducted on 195 HIV/AIDS patients with fever of unknown origin admitted to our hospital from January 2016 to June 2019. We recorded clinical parameters, immune status and etiologies for each patient. Patient immune status based on TCD4 counts was stratified into three levels: &lt; 50 cells/mm3; 50 - 100 cells/mm3 and &gt; 100 cells/mm3. We determined the prolonged fever etiologies in HIV infected patients and compared the distributionof these etiologies in different TCD4 count levels. &#x0D; Results: Among 195 HIV - infected cases with fever of unknown origin, opportunistic infections accounted for 93.3%, non - infectious etiologies took 3.6% and 3.1% were not identified causes. M. tuberculosis was the most common opportunistic infection (46.7%), followed by Talaromycosis (29.2%) and Pneumocytisjiroveci (20.5%), Bacterial pneumonia (11.3%), sepsis (10.3%), CMV (10.3%), Toxoplasma (5.6%), Cryptococcus (2.6%) and MAC (1.0%). Tuberculosis was predominant in all stratified CD4 levels. Most of cases with Talaromycosis had CD4 counts below 50cells/mm3. Besides, CD4 count below 50cells/mm3 was reported in all cases with either Cryptococcus infection or MAC infection. Infections with CMV and toxoplasma were not seen in patients with CD4 count over 100cells/mm3. -7 out of 195 cases were non - infectious etiologies including 4 cases (2.1%) with hemophagocytic lymphohistiocytosis (HLH) syndrome and 3 cases (1.5%) with non - Hodgkin lymphoma. -53.8% of cases were infected by one pathogen while 38% of patients were co - infected by two different pathogens. Co - infection of three pathogens was recognized in 8.2% of study patients.There is no difference between the number of concurrent etiologies and TCD4 levels. &#x0D; Conclusion: Opportunistic infections, especially M. tuberculosis is still the leading cause of prolonged fever in HIV/AIDS patients. T. marnefei should be screened in patients with CD4 &lt; 50cells/mm3. It is important to note that there may be many concurrent etiologies of prolonged fevers in HIV/AIDS patients.

The function and regulation of heat shock transcription factor in Cryptococcus.

Cryptococcus species are opportunistic human fungal pathogens. Survival in a hostile environment, such as the elevated body temperatures of transmitting animals and humans, is crucial for Cryptococcus infection. Numerous intriguing investigations have shown that the Hsf family of thermotolerance transcription regulators plays a crucial role in the pathogen-host axis of Cryptococcus. Although Hsf1 is known to be a master regulator of the heat shock response through the activation of gene expression of heat shock proteins (Hsps). Hsf1 and other Hsfs are multifaceted transcription regulators that regulate the expression of genes involved in protein chaperones, metabolism, cell signal transduction, and the electron transfer chain. In Saccharomyces cerevisiae, a model organism, Hsf1's working mechanism has been intensively examined. Nonetheless, the link between Hsfs and Cryptococcus pathogenicity remains poorly understood. This review will focus on the transcriptional regulation of Hsf function in Cryptococcus, as well as potential antifungal treatments targeting Hsf proteins.

Advanced HIV disease: A review of diagnostic and prophylactic strategies.

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. 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. 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. 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.

Abstract 6753: Non-HIV cryptococcal patients with hematological malignancies: A retrospective analysis of a ten-year study from a Peruvian oncologic center

Abstract Background Globally, cryptococcal infection has become a public health challenge. However, relatively little is known about cryptococcal infection in people with hematological disorders. Methods We developed a retrospective cohort study that includes hematological patients who had cryptococcosis infection seen in the Instituto Nacional de Enfermedades Neoplasicas between 2007 and 2017. Results During the 11-year study period, a total of 21 cases of cryptococcosis (incidence rate of 13,4 per 1000 hematological malignancies). The time of diagnosis of cryptococcosis since hematologic malignancy diagnosis was 42 (18-161) days. Non-Hodgkin lymphoma (NHL) was the most frequent malignancy (47.6%), followed by leukemias (23.8%), multiple myeloma in (19.1%), and HL (9.5%). Three cases of adult T-cell leukemia/lymphoma associated with HTLV-1 infection were identified in the NHL. Cryptococcemia was the most frequent diagnosis (85.7%) followed by pulmonary (52.4%) and CNS (38.1%) involvement. Regarding clinical presentation, f ever was the most common symptom in meningeal cryptococcosis (76.2%) and dyspnea in pulmonary cryptococcosis (61.9%). The use of immunosuppressant chemotherapy within a month before the diagnosis of cryptococcosis was the most common risk factor. The main characteristics between patients with cryptococcosis and type of neoplasms (NHL vs other hematological neoplasms) such as age at admission, site of presentation of cryptococcosis, and lymphocyte count at admission were different significantly between these groups. In the NHL group, there was less involvement of the lungs. Overall survival (OS) in 15 and 120 days were 70% (95%CI: 0.43-0.86) and 51% (95%CI: 0.26-0.72), respectively. OS for patients with NHL was 57% at 15 days (95% CI: 0.17-0.83) and 42% at 120 days (95%CI:0.09-0.73). OS for other hematological malignancies was 90% at 15 days (95%CI:0.47-0.98) and 60% at 120 days (95%CI: 0.25-0.82). Conclusions CNS cryptococcal infection was more frequent in patients with NHL. Citation Format: Kelly Meza, Luis E. Cuellar. Non-HIV cryptococcal patients with hematological malignancies: A retrospective analysis of a ten-year study from a Peruvian oncologic center. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6753.

Intelligent diagnostic system for Cryptococcus: Switch-controllable nanocatcher and CNN-based artificial intelligence

Each year, one million Cryptococcal infections occur among people living with HIV/AIDS, resulting in nearly 625,000 fatalities due to low efficiency of clinical diagnostic procedures and misdiagnosis caused by faulty subjective judgment of manually enumerated imaging-based infection assays. In order to improve the diagnostic efficiency of non-immunodeficient patients infected with Cryptococcus, the present study developed an intelligent diagnostic system combined with a switch-controllable nanocatcher (MNP@PNIPAMAA-CAS) with high capture performance for Cryptococcus and convolutional neural network (CNN)-based artificial intelligence (AI), which was utilized to analyze the collected pathological images for subsequent diagnosis. This system benefitted from the high adsorption efficiency of the MNP@PNIPAMAA-CAS and the objective data processing ability of AI. The system’s detection limit was 1–4 cells /mL, the specificity was 97%, and the detection time was only 6 min. The intelligent diagnostic system will provide significant benefit to the diagnosis of clinical fungi due to its high sensitivity, high specificity, and superfast detection speed.

Cutaneous Cryptococcus Infection and Suspected Kaposi Sarcoma of the Hand in an Immunocompromised Patient.

Cryptococcal infection is well-documented in immunocompromised individuals. Cutaneous manifestations are not as common and are often difficult to diagnose due to variable presentations. Furthermore, there have been reports of coexisting cutaneous Cryptococcus and malignancy. We describe a patient that presented with a fast-growing mass (suspected sarcoma) in the hand that was ultimately treated for a Cryptococcus skin infection. We believe familiarity with the possibility of coexistence of these two conditions in an immunocompromised host could have brought about earlier diagnosis and possibly more effective treatment. Level of Evidence: Level V (Therapeutic).

C1q Confers Protection Against Cryptococcal Lung Infection by Alleviating Inflammation and Reducing Cryptococcal Virulence.

To define the role of C1qa in host defense against Cryptococcus neoformans lung infection, we investigated its susceptibility to cryptococcal lung infection in mice deficient in complement factor C1qa (C1qa-/- ). We established a wild-type (WT) and C1qa-deficient murine inhalation model with C. neoformans. We compared the host survival rate, inflammatory responses, and pathogenicity of C. neoformans during the infection course between WT and C1qa-/- mice. The mortality rate of C1qa-deficient mice was significantly higher than that of wild-type mice. The increased formation of Titan cells in the lungs was associated with augmented inflammation in C1qa-deficient mice. The capacity of lung homogenate supernatant from C1qa-deficient mice to induce Titan formation in vitro was greater compared with that of wild-type mice. The C. neoformans isolated from the lungs of infected C1qa-deficient mice was more resistant to macrophage killing in vitro and caused significantly higher mortality after administration to mice compared with that isolated from WT mice. These findings reveal a novel role of C1qa in host defense against C. neoformans infection by regulating host inflammation and pathogen virulence and provide new insight into the C1q-mediated lung environment underlying the transition from yeast to Titan cell.

Antifungal Peptide SP1 Damages Polysaccharide Capsule of Cryptococcus neoformans and Enhances Phagocytosis of Macrophages.

Cryptococcus neoformans is a fungal pathogen which causes nearly half a million deaths worldwide each year. Under host-relevant conditions, it produces a characteristic polysaccharide capsule. The polysaccharide capsule is one of the main virulence factors of C. neoformans, which involves antiphagocytosis and immune responses of the host to cause a lack of an immune. Meanwhile, the polysaccharide capsule is a promising drug target because of the absence of analogs in the host. Here, we demonstrate that antifungal peptide SP1, which is derived from the N terminus of Saccharomyces cerevisiae GAPDH (glyceraldehyde-3-phosphate dehydrogenase), disrupts the polysaccharide capsule of C. neoformans H99. The mechanism is possibly due to the interaction of SP1 with glucuronoxylomannan (GXM). Disruption of the polysaccharide capsule enhances the adhesion and phagocytosis of C. neoformans H99 by macrophages and reduces the replication of C. neoformans H99 within macrophages. Additionally, SP1 exhibits antifungal activity against cryptococcal biofilms associated with the capsular polysaccharides. These findings suggest the potential of SP1 as a drug candidate for the treatment of cryptococcosis. IMPORTANCE C. neoformans is an opportunistic pathogen that causes invasive infections with a high mortality rate. Currently, the clinical drugs available for the treatment of cryptococcosis are limited to amphotericin B, azoles, and flucytosine. Amphotericin is nephrotoxic, and the widespread use of azoles and 5-flucytosine has led to a rapid development of drug resistance in C. neoformans. There is an urgent need to develop new and effective anticryptococcal drugs. Targeting virulence factors is a novel strategy for developing antifungal drugs. The antifungal peptide SP1 is capable of disrupting the polysaccharide capsule, which is a principal virulence factor of C. neoformans. Studying the mechanism by which SP1 damages the polysaccharide capsule and investigating the potential benefits of SP1 in removing C. neoformans from the host provides baseline data to develop a therapeutic strategy against refractory cryptococcal infections. This strategy would involve both inhibiting virulence factors and directly killing C. neoformans cells.

Promising whole-cell vaccines against cryptococcosis.

Cryptococcosis is a mycosis caused by Cryptococcus neoformans and C. gattii species complexes. Although this infection is potentially lethal, no prophylactic vaccine is yet commercially available, and the immune memory that enables prevention is still under investigation. These pathogens have a capsule layer for immune evasion and a sophisticated mechanism to advance the infection, and it is expected that these characteristics will make it difficult to develop prophylactic vaccines and to decipher the protective immunity. The current vaccine studies are focused on subunit, mRNA, DNA, and viral vector vaccines, with whole-cell vaccines also proving successful against cryptococcal infections. Cryptococcal whole-cell vaccines have been composed of highly immunostimulating strains with low-pathogenicity that are modified by genetic recombination technology. Examples include the whole-cell vaccines H99γ, sgl1∆, fbp1∆, znf2oe , cda1/2/3∆, cap59∆, and cap60∆. Some of these whole-cell vaccines were found to be highly effective in prolonging life and suppressing the fungal burden after an infection challenge in mice, and to be cross-reactive to C. neoformans, C. gattii, and other fungal pathogens. Furthermore, for some vaccines, the protective effect can be retained even in an immunocompromised host depleted of CD4+ T cells. These findings have provided new insights into protective immunity that should aid in vaccine development. In this review, we highlight the upsides and downsides of whole-cell vaccines against cryptococcosis.