Download NEUT-X ~ A useful predictor for film review in undiagnosed

NEUT-X ~ A useful predictor for film
review in undiagnosed Myelodysplastic
Syndrome
T. Kidd1, E. Tegg1,2
1. Core Laboratory – Haematology, Royal Hobart Hospital, 2. School of
Medicine, University of Tasmania, Hobart, TAS, Australia
Introduction
• Myelodysplastic syndromes (MDS) are clonal
haematopoietic stem cell disorders with a poor prognosis.
• Primarily a disease of the elderly (70+ years), it is often a
disease of exclusion. Haematological parameters typically
indicate an isolated anaemia or anaemia in conjunction
with another cytopaenia which is fairly innocuous and
could fit a multitude of disease states. These anaemias,
which are often transfusion dependent, are generally the
primary cause of morbidity and mortality.
• Consequently early diagnosis is essential to optimise
treatments, such as medications that stimulate
erythropoiesis and methylating agents, which prolong
transfusion independence.
Methods
• Raw data, 20,000 records, was downloaded from both Sysmex
XE5000 analysers at the RHH. The study period was 14 February to
31 March 2012.
• The target group consisted of initial patient FBC with a NEUT-X ≤
1299 and one or more of the following; MCV > 96 fL, Absolute
Neutrophils (Neut#) <1.5x109/L, Haemoglobin (Hb) <100 g/L or
Platelet count (Plt) <100x109/L.
• The control group consisted of two match controls for each target
patient.
• A manual neutrophil differential was performed (under oil, x1000)
to determine the percentage of hypogranular neutrophils present.
• Correlation between the NEUT-X value and the gold standard
microscopically defined hypogranularity of the neutrophils was
assessed by simple linear regression.
• Means and standard deviations (SD) of NEUT-X were evaluated as a
predictor for the selection of film review for the diagnosis of MDS.
Sensitivity and specificity values were assessed by the use of
receiver operating characteristic (ROC) curve analysis.
Results
• 43 patients had a low NEUT-X value. Mean and SD values
were significantly different between the MDS (+), target (?
MDS) and control groups at 1223 ± 82, 1273 ± 28 and 1326
± 15 respectively.
• The area under the receiver operating characteristic (ROC)
curve was 0.863 (95% confidence interval: 0.802 to 0.911)
demonstrating that NEUT-X has diagnostic utility
irrespective of presence of hypogranular neutrophils.
• The predictive value of NEUT-X in the diagnosis of MDS,
sensitivity 84.2% and specificity 74.3%, validates the
benefit of incorporating this parameter into film review
criteria.
Conclusion
• The inclusion of the NEUT-X
parameter into film review
selection criteria in
combination with an alert
to the morphologist to
perform, if required, a
manual neutrophil
differential (under oil) to
determine the presence of
hypogranular neutrophils
should aid in the earlier
detection of MDS.
Figure 1 - Correlation between NEUT-X and PBDG in the, MDS (+)
group represented by the red squares (n=19) and the Total Study
cohort [combined Target (? MDS) and Control Groups] shown as
the blue diamonds (n=152). GREEN line indicates a NEUT-X of
1253, the proposed cut off value to be included in the new film
review criteria