Cryptococcal Antigen Screening Evaluated Among People Living with HIV
|
By LabMedica International staff writers Posted on 03 Jun 2021 |

Image: The CrAg LFA (lateral flow assay) can detect cryptococcal antigens in the blood of asymptomatic patients prior to development of cryptococcal meningitis enabling pre-emptive treatment of CrAg positive patients (Photo courtesy of Immy Diagnostics)
Cryptococcosis is a potentially fatal fungal disease caused by a few species of Cryptococcus (most often Cryptococcus neoformans or Cryptococcus gattii). Cryptococcosis is believed to be acquired by inhalation of the infectious propagule from the environment.
Most people in the USA who develop cryptococcal infections are HIV-positive. However, occasionally persons with no apparent immune system problems develop cryptococcosis. Cryptococcosis remains a leading cause of meningitis and mortality among people living with HIV (PLHIV) worldwide.
An international team of scientists led by the University of Washington (Seattle, WA, USA) evaluated laboratory-based cryptococcal antigen (CrAg) reflex testing and a clinic-based point-of-care (POC) CrAg screening intervention for preventing meningitis and mortality among PLHIV in South Africa. The team included 3,105 (39.4%) of 7,877 people screened were HIV-positive, of whom 908 had CD4 ≤200 cells/mm3 and were included in the analyses. The laboratory and clinical teams performed serum CrAg by enzyme immunoassay and lateral flow assay (Immy Diagnostics, Norman, OK, USA).
The investigators reported that Lab reflex and clinic-based testing significantly increased CrAg screening and diagnosis of CrAg-positive PLHIV. As compared to clinician-directed testing, clinic-based CrAg testing increased the number of PLHIV diagnosed with cryptococcal meningitis (4.5% compared to 1.5%), initiation of fluconazole pre-emptive therapy (7.2% compared to 2.5%), and initiation of ART (96.8% compared to 91.3%). Comparing clinic-based testing to lab reflex testing, there was no significant difference in the cumulative incidence of cryptococcal meningitis (4.5% compared to 4.1%) or mortality (8.1% compared to 9.9%).
The authors concluded that Lab reflex and clinic-based CrAg testing facilitated diagnosis of HIV-associated cryptococcosis and fluconazole initiation, but did not reduce cryptococcal meningitis or mortality. In this non-randomized cohort, clinical outcomes were similar between lab reflex testing and clinic-based point-of-care CrAg testing. The study was published on May 10, 2021 in the Journal of Acquired Immune Deficiency Syndromes.
Related Links:
University of Washington
Immy Diagnostics
Most people in the USA who develop cryptococcal infections are HIV-positive. However, occasionally persons with no apparent immune system problems develop cryptococcosis. Cryptococcosis remains a leading cause of meningitis and mortality among people living with HIV (PLHIV) worldwide.
An international team of scientists led by the University of Washington (Seattle, WA, USA) evaluated laboratory-based cryptococcal antigen (CrAg) reflex testing and a clinic-based point-of-care (POC) CrAg screening intervention for preventing meningitis and mortality among PLHIV in South Africa. The team included 3,105 (39.4%) of 7,877 people screened were HIV-positive, of whom 908 had CD4 ≤200 cells/mm3 and were included in the analyses. The laboratory and clinical teams performed serum CrAg by enzyme immunoassay and lateral flow assay (Immy Diagnostics, Norman, OK, USA).
The investigators reported that Lab reflex and clinic-based testing significantly increased CrAg screening and diagnosis of CrAg-positive PLHIV. As compared to clinician-directed testing, clinic-based CrAg testing increased the number of PLHIV diagnosed with cryptococcal meningitis (4.5% compared to 1.5%), initiation of fluconazole pre-emptive therapy (7.2% compared to 2.5%), and initiation of ART (96.8% compared to 91.3%). Comparing clinic-based testing to lab reflex testing, there was no significant difference in the cumulative incidence of cryptococcal meningitis (4.5% compared to 4.1%) or mortality (8.1% compared to 9.9%).
The authors concluded that Lab reflex and clinic-based CrAg testing facilitated diagnosis of HIV-associated cryptococcosis and fluconazole initiation, but did not reduce cryptococcal meningitis or mortality. In this non-randomized cohort, clinical outcomes were similar between lab reflex testing and clinic-based point-of-care CrAg testing. The study was published on May 10, 2021 in the Journal of Acquired Immune Deficiency Syndromes.
Related Links:
University of Washington
Immy Diagnostics
Latest Immunology News
- Immune Biomarkers Could Identify Risk of Chronic Critical Illness on ICU Admission
- Emergency Department Opt-Out Testing Program Identifies Undiagnosed HIV
- Airway Immune Signature May Predict Tuberculosis Progression Risk
- New Cellular Biomarkers Correlate with Disease Severity in Sjögren Disease
- Lung Immune Profiling Reveals Distinct Severe Pneumonia Subtypes
- Lab-on-a-Chip Approach Advances Immune–Cancer Cell Interaction Analysis
- Antibody Profiles Provide Clues to Long COVID Severity and Symptoms
- Aptamer-Based Biosensor Enables Mutation-Resilient SARS-CoV-2 Detection
- Metabolic Biomarker Distinguishes Latent from Active Tuberculosis and Tracks Treatment Response
- Study Points to Autoimmune Pathway Behind Long COVID Symptoms
- Immune Enzyme Linked to Treatment-Resistant Inflammatory Bowel Disease
- Simple Blood Test Could Replace Biopsies for Lung Transplant Rejection Monitoring
- Routine TB Screening Test May Reveal Immune Aging and Mortality Risk
- Biomarkers and Molecular Testing Advance Precision Allergy Care
- Point-of-Care Tests Could Expand Access to Mpox Diagnosis
- T-Cell Senescence Profiling May Predict CAR T Responses
Channels
Clinical Chemistry
view channel
FDA-Approved Test Identifies Low Risk of Large Esophageal Varices in Cirrhosis
Chronic liver disease contributes substantially to mortality, and clinicians routinely screen adults with compensated cirrhosis for varices to prevent bleeding. However, endoscopy is invasive and reso... Read more
Blood Protein Signature Diagnoses Pediatric IBD and Distinguishes Subtypes
Confirming pediatric inflammatory bowel disease (IBD) often requires imaging, endoscopy, and histopathology, prolonging time to diagnosis. Reliable, noninvasive blood tests remain an unmet need in routine... Read moreMolecular Diagnostics
view channel
Framework Outlines Genomic Testing Strategy for Safer Drug Dosing in Africa
Variation in drug response remains a major obstacle to safe, effective therapy, particularly across genetically diverse populations. Many dosing recommendations for essential medicines are derived from... Read more
CSF Sequencing Test Aligns with Updated Brain Tumor Guidelines
Accurate genomic characterization of central nervous system tumors can be challenging when surgery or stereotactic biopsy is not feasible because of tumor location, patient health, or surgical risk.... Read moreHematology
view channel
Next-Generation Hematology Platform Streamlines High-Complexity Lab Workflows
Sysmex America (Chicago, IL, USA) has introduced the next generation XR-Series, centered on the XR-10 Automated Hematology Module for high-complexity laboratories. The platform builds on the widely used... Read more
Blood Eosinophil Count May Predict Cancer Immunotherapy Response and Toxicity
Immune checkpoint inhibitors have improved outcomes across many cancers, yet only a subset of patients derive durable benefit and biomarkers to guide treatment remain limited. Eosinophils, best known for... Read moreMicrobiology
view channel
H. pylori Screening Within Colorectal Program Aids Gastric Cancer Prevention
Health systems increasingly rely on economic evidence to guide cancer prevention strategies. For gastric cancer, selecting screening approaches that can integrate with existing programs is a key policy question.... Read more
Machine Learning Reveals Consistent Gut Microbiome Patterns in Colorectal Cancer
Colorectal cancer has been repeatedly linked to alterations in the gut microbiome, yet findings have often varied across small, heterogeneous studies. Reproducibility has been limited by differing sequencing... Read morePathology
view channel
AI Pathology Tool Predicts Immunotherapy Response in Rare Cancers
Immunotherapy has transformed care for select malignancies, yet predicting which patients with rare cancers are most likely to benefit remains challenging. Clinicians often have only limited biomarkers... Read more
Uncertainty-Aware AI Tool Improves Digital Pathology for Cancer Subtyping
Reliable histologic subtyping guides therapy selection in oncology, yet diagnostic workflows grow more complex as whole-slide imaging and artificial intelligence (AI) expand. A persistent obstacle to clinical... Read moreTechnology
view channel
AI Platform Links Biomarker Results to Cancer Clinical Trials and Guidelines
Oncology teams must manage growing volumes of genomic data, rapidly evolving clinical trial options, and frequently updated care guidelines, all within tight clinic schedules. Translating complex tumor... Read more
Agentic AI Platform Supports Genomic Decision-Making in Oncology
Oncology care teams increasingly face the challenge of managing complex molecular diagnostics, evolving treatment options, and extensive electronic health record documentation. Translating multimodal data... Read moreIndustry
view channel
Partnership Integrates Automated DNA Extraction with Single-Molecule Digital PCR
Countable Labs (Palo Alto, CA, USA) and Promega (Madison, WI, USA) have entered a co-marketing agreement that integrates the Promega Maxwell System for nucleic acid extraction with Countable Labs’ Countable... Read more








