Aspergillus antigen: Determination of the presence of Aspergillus antigen (galactomannan) in serum or BAL.
B D Glucan: Determination of the presence of 1-3 Beta- D- glucan (fungal cell wall antigen) in serum.
Aspergillus antigen: The detection of circulating galactomannan in serum is an important tool for the early diagnosis of invasive Aspergillosis. Invasive aspergillosis (IA) represents a major threat in patients with depressed immune system. IA is increasingly observed in patient populations with diverse types of underlying diseases and level of immunosuppression, such as solid-organ transplant recipients, patients with solid tumours, auto-immune disorders, congenital immunodeficiency or chronic pulmonary diseases. The pathogenesis and clinical presentation of IA may differ in these settings with various degrees of invasiveness.
B D Glucan: Unlike Aspergillus antigen detection, detection of B D Glucan provides a non-specific indication of invasive aspergillosis, invasive candidiasis or other invasive mycoses.
Aspergillus antigen: For the Aspergillus antigen test an index value of 0.5 or greater is considered a positive result for serum samples. A higher index value of greater than 1 would be considered positive for bronchoalveolar lavage samples.
B D Glucan: The Beta glucan test has a cut off value of 80 pg/mL, in our experience two consecutive positive values enhances the clinical significance. Not all fungi produce Beta glucan and there are other factors that can lead to raised Beta glucan levels. Please contact the laboratory for further information.
Aspergillus antigen: Yellow top serum separator blood or BAL.
B D Glucan: Yellow top serum separator blood.
- 1-2ml of serum is required for Aspergillus anitgen / B D Glucan testing.
- 600µl minimum of BAL is required for Aspergillus antigen testing.
Limitations & Restrictions
BAL will not be tested for B D Glucan
- Aspergillus antigen: 1-2 working days
- B D Glucan: 1-3 working days
PHE Mycology Reference Laboratory, National Infection Services, PHE South West Laboratory, Science, Quarter, Southmead Hospital, Bristol, BS10 5NB