Flow cytometry is a sensitive and informative tool in PNH diagnosis and monitoring 1,2
ICCS guidelines recommend routine (1% PNH cell threshold) or high-sensitivity (0.01% PNH cell threshold) flow cytometry for patients at high risk of PNH 1
Early diagnosis is essential for improved patient management and prognosis 3,4
IDENTIFY PATIENTS WITH PNH EARLY WITHIN HIGH-RISK GROUPS1,2,5-14
IDA = iron deficiency anaemia; MDS = myelodysplastic syndrome. *Anaemia, neutropenia, thrombocytopenia, or pancytopenia. †Unusual sites include hepatic veins (Budd-Chiari syndrome), other intra-abdominal veins (portal, splenic, splanchnic), cerebral sinuses, and dermal veins. ‡Detects PNH cells down to at least 0.01 clone size.
RBC analysis alone is not enough 1,2
Evaluation of RBCs alone may under-report clone size due to haemolysis and the dilution effect of transfusions 1-2,15,17 Granulocytes give the most accurate estimate of PNH lone size 1,2,11
Analysis of granulocytes and RBCs in a patient with PNH 1
PNH granulocyte clone: 55%
Adapted from Borowitz et al, 2010
PNH RBC clone: 6%
Ongoing Monitoring of PNH Clone Size is Important 1,2,16
Adapted from Movalia et al, 2011
Study design: High sensitivity flow cytometry, with sensitivity up to 0.01%, was used to analyse 6,897 patients who were screened for PNH clones. The study included an examination of the change in PNH clone sizes among patients who had follow-up studies in 3–12 months.
Annual monitoring should be considered even for patients with a PNH clone size of < 0.1%.
For patients with a PNH clone size of > 1%, monitoring at least semi-annually is recommended.16