Diagnostic value of mean Peroxidase index in early Kawasaki disease
The charts of 27 patients with Kawasaki disease (KD) admitted to Nemazee Hospital in Shiraz from January 1991 to October 1998 were reviewed to identify the results of mean peroxidase index (MPXI) values, a measure of neutrophil staining intensity, obtained buy the Technicon H1 analyzer (Technicon Instruments Corp., Tarrytown, NY) within the first 10 days of the illness; 2 separate groups of patients were assessed as control subjects: 27 disease control (DC) children with fever plus one other KD criterion; and 27 laboratory control (LC) subjects with non-febrile disorders interpreting also as a normal reference population. Compared with control groups, patients with KD had lower quantities of MPXI [(Mean±SD, -11.71±5.87 in KD group) vs. (1.53±4.30; P<0.001 in DC group and 1.74±6.52, P<0.001 in LC group)]. Depending on the location of the cut-off point expressed on an interval scale, this test had the ability to be 100% specific (If MPXI<-6.0) and 100% sensitive (If MPXI>0). Considering the low prevalence of hereditary myeloperoxidase (MPO) deficiency (1 in 2000), measurement of MPXI, when performed as part of a complete count on an automated hematology instrument, could be counted as an important adjunct to clinical evaluation and also according to the low values of MPXI in patients with KD, it can be included among the acquired causes of MPO deficiency.