While glycocerebrosidase and galactocerebrosidase presented a positive correlation with the number of neutrophils, sphingomyelinase showed a positive correlation with the number of lymphocytes.
General characteristic of study population n Mean [+ or -] SD Gender (male/female) 263 128/135 Glycocerebrosidase (nmol/mL/h) 263 1.87[+ or -]1.44 [alpha] glycosidase (nmol/mL/h) 198 2.62[+ or -]1.34 [alpha] galactosidase (nmol/mL/h) 213 6.03[+ or -]3.67 Sphingomyelinase (nmol/mL/h) 181 10.32[+ or -]7.81 Galactocerebrosidase (nmol/mL/h) 170 1.33[+ or -]0.89 Hemoglobin (g/dL) 263 11.94[+ or -]1.89 Hematocrite (%) 263 36.71[+ or -]5.43 Total leucocyte/[mm.sup.3] 263 8.916[+ or -]3.748 Neutrophil number/[mm.sup.3] 263 3.861[+ or -]2.261 Lymphocyte number/[mm.sup.3] 263 3.846[+ or -]2.482 Thrombocyte number/[mm.sup.3] 263 291.839[+ or -]122.747 SD: Standard deviation
 Nonstandard abbreviations: GALC, galactocerebrosidase
; MS/MS, tandem mass spectrometry; GALC-S, galactosylceramide with a 7-carbon heptanoyl chain; GALC-IS, GALC internal standard; GALC-P, GALC product; GLB1, human [beta]-galactosidase-1; MRM, multiple reaction monitoring; LC, liquid chromatography; dpm, disintegration per minute; EIKD, early-infantile Krabbe disease; LOKD, late-onset Krabbe disease.
Lysosomal enzyme testing showed galactocerebroside beta galactosidase or galactocerebrosidase (GALC) level which was almost undetectable and definitely much below the 99th percentile for age and sex confirming the diagnosis of Krabbe disease.
Spectrophotometric and fluorimetric assays of galactocerebrosidase activity, their use in the diagnosis of Krabbe's disease.
A 5-plex cocktail to assay [beta]-glucosidase (ABG), acid [alpha]-glucosidase (GAA), galactocerebrosidase
(GALC), [alpha]-galactosidase A (GLA), and [alpha]-L-iduronidase (IDUA) activity was based on the method described by Orsini et al.
 Nonstandard abbreviations: LSD, lysosomal storage disease; MS/MS, tandem mass spectrometry; DBS, dried blood spot(s); ASM, acid sphingomyelinase; GAA, [alpha]-acid-glucosidase; GLA, [alpha]-galactosidase A; ABG, acid [beta]-glucocerebrosidase; GALC, galactocerebrosidase
; IDUA, [alpha]-iduronidase; ID2S, iduronate-2-sulfatase; GAL6S, N-acetyl-galactosamine-6-sulfatase; GAL4S, N-acetyl-galactosamine-4-sulfatase; UHPLC, ultra-HPLC; SRM, selected reaction monitoring; MRM, multiple reaction monitoring; [A.sub.e], enzyme activity.
 Nonstandard abbreviations: MS/MS, tandem mass spectrometry; LSD, lysosomal storage disorder; MPS, mucopolysaccharidosis; LLE, liquid-liquid extraction; SPE, solid-phase extraction; Turboflow, turbulent flow chromatography; UHPLC, ultra-HPLC; DBS, dried blood spots; NBS, newborn screening; ABG, acid /3glucocerebrosidase; GLA, [alpha]-galactosidase; GAA, a-glucosidase; ASM, acid sphingomyelinase; GALC, galactocerebrosidase
; DUA, iduronidase.