| Objective:Galactitol concentration in the urine sample of patient with NICCD (neonatal intrahepaticcholestas is caused by citrin deficiency, NICCD ) was analyzed by GC/ MS (Gaschromatography-Mass spectrometry) to establish a biochemical criteria to screen the patientswith NICCD among the population, and the relationship between the genotype of NICCD andgalactitol concentration in the urine was studied. Furthermore, the difference of galactitolconcentration analyzed by GC/MS from different size and different duration time of dried urinefilter paper sample and original urine sample were observed to study the possibility oftransporting the sample by dried urine filter paper in order to screen the patients with NICCD.Methods:1. The urine sample, from 15 patients, whose genotype of NICCD were identified bySLC25A13 genetic mutation analysis of peripheral blood, both pre-therapy and post-therapy, 10patients with virus hepatitis and 60 healthy children, were collected.2. Original urine samples were analyzed by gas chromatography-mass spectrometryafter urea had been removed by urease.3. Metabolites in urine were identified by mass spectrometry and NIST library.4. Heptadecanoic acid was used as internal standard and metabolites concentration inurine were calculated up on creatinine concentration.5. Ten galatitol positive original urine samples analyzed by GC/MS were collected.6. Each sample was absorbed by 3 different size of filter paper, then dried and placeunder the room temperature for 1～7 days, then eluated.7. 100μL sample of original urine and elution was collected to measure theconcentration of the urin creatinine by biochemical method.8.100μL of original urine sample and elution sample were collected and measuredas method 2-4.9. Non-normal distributed data presented as media(M) and 95%confidenceinterval(95%CI). Statistical evaluation for nonparametric data was carried out using theKruskal-Wallis test, if there was statistical significance , Mann-Whitney U test was used toevaluate the difference between two groups. The level of significance was P＜0.05.Results:1.Galactitol concentration in the urine sample before therapy in patient with NICCDhas significant difference with patients with virus hepatitis and healthy people; 2. There was no significant differences in galactitol concentration in the urin samplebefore therapy between patient with type I homozygote NICCD and type I heterozygoteNICCD.3. There was a significant difference in galactitol concentration in the urin samplebetween pre-therapy and post-therapy in patients with type I homozygote NICCD or type Iheterozygote NICCD.4. Urine filter paper sample collected from same patient, compared with original urine,the galactitol concentration in the urine has no significant differences after being placed in roomtemperature for 1, 3, 5or7 days.Conclusion:1. An marked increase in galactitol concentration analyzed by GC-MS in the urine sampleusually means the possibility of NICCD.2. Galactitol concentration analyzed by GC-MS in the urine sample has no use inidentifying the genotype of NICCD.3. At the room temperature, when the volume of elution is equal to the volume of urineabsorbed by the filter paper and the duration time is less than 7 days, deep froze original urinesample can be replaced by urine filter paper sample. The size of the filter paper should be: 5cm×8cm, and it can absorb 1.0 mL urine. |
PDF Full Text Request