Specimen must arrive within 24 hours for analysis.

Send to tube station #260 or deliver to Specimen Control, 6240 RCP.

An interpretative report will be provided by the pathologist.

Ham's acid hemolysin and sucrose lysis tests have been replaced 

by flow cytometric testing for glycosylphosphatidyl inositol (GPI)-

anchored proteins CD14 and CD24, and aerolysin binding. These proteins 

are not expressed on PNH white blood cells and their lack of 

expression is determined by flow cytometric assay. 



The channel-forming toxin, aerolysin, and its inactive precursors, 

proaerolysin, bind selectively with a high affinity to the GPI anchor 

itself. The lack of GPI anchor on blood cell surface will decrease the 

ability of fluorescently labeled protein aerolysin (FLAER) to bind to 

nucleated blood cells in patients with PNH. 



Determination of CD14 and CD24 must be performed on fresh whole blood. 

Both monocytes and granulocytes are analyzed for CD14/CD24 expression 

and aerolysin bindings. Granulocytes are the most sensitive population 

in which to detect GPI-anchored protein deficiency. Two additional 

markers are performed for gating purposes, CD45 (leukocyte common 

antigen) and CD15 (myeloid antigen). 



REFS: 

1)Richards, S et al. Application of Flow Cytometry to the Diagnosis of 

Paroxysmal Nocturnal Hemoglobinuria. Cytometry 2000; 42:223-233. 

2)Dunn, D, et al. Paroxysmal Nocturnal Hemoglobinuria in Patients with 

Bone Marrow Failure Syndromes. Ann Int Med 1999; 131:401-408. 

3) Brodsky RA, et al. Improved detection and characterization of 

paroxysmal nocturnal hemoglobinuria using fluorescent aerolysin. Am J 

Clin Pathol 2000; 114:459-66. 

Flow Cytometry

Technical:     88184 x1 and 88185 x6

Professional:  88187