What is the Cryptococcus Serum Antigen Test?

The Cryptococcus Serum Antigen (CrAg) Test is a highly sensitive blood test that detects antigens produced by Cryptococcus neoformans and Cryptococcus gattii. It is widely used for the early diagnosis of cryptococcal infection, especially in people with weakened immune systems. Early detection allows timely treatment and may help prevent life-threatening complications such as cryptococcal meningitis.

Who should take this test?

• Individuals living with HIV/AIDS, especially with low CD4 counts.
• Organ transplant recipients receiving immunosuppressive therapy.
• Patients with persistent fever, severe headache, or neurological symptoms.
• Individuals with suspected fungal infections.
• Patients undergoing evaluation for cryptococcal disease.
• Doctor-recommended screening in immunocompromised individuals.

Preparation & Test Process

Understanding Your Results

Positive results indicate the presence of Cryptococcus antigen and strongly suggest cryptococcal infection. Further evaluation and prompt antifungal treatment may be required.

Negative results indicate that cryptococcal antigen was not detected. However, early infection or localized disease cannot always be completely excluded.

Results should always be interpreted together with your symptoms, immune status, clinical examination, and other laboratory findings.

FAQs – Cryptococcus Serum Antigen (CrAg) Test