Validacija referentnog intervala za žučne kiseline za populaciju trudnica od 28. do 42. tjedna trudnoće

master's thesis

• Title (english): Validation of reference interval for bile acids for the population of pregnant women from 28th to 42nd week of pregnancy
• Author: Lara Zorić
• Mentor: Lora Dukić (mentor)
• Mentor: Vladimir Blagaić (mentor)
• Committee member: Lora Dukić (predsjednik povjerenstva)
• Committee member: Sandra Šupraha-Goreta (član povjerenstva)
• Committee member: Ana-Maria Šimundić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; Zagreb
• Defense date and country: 2022-08-31, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Pharmacy; Pharmacy

Abstract

Usporedba laboratorijskih nalaza pacijenata s referentnim intervalima jedan su od najprimjenjivijih alata za interpretaciju nalaza, postavljanje dijagnoze i praćenje tijeka bolesti. Cilj ovog rada bio je uvesti metodu za određivanje žučnih kiselina u analitički sustav i verificirati njene parametre, te izraditi referentni interval za žučne kiseline za populaciju trudnica od 28. do 42. tjedna trudnoće. U populaciji trudnica žučne kiseline kao specifični biomarker služe za postavljanje dijagnoze intrahepatičke kolestaze u trudnoći, bolesti koja se javlja u trećem tromjesečju i ispoljava kao pruritus, a može biti fatalna za dijete.
Verifikacijom metode je utvrđeno da su žučne kiseline stabilne 2 dana pri 20 ℃, 14 dana pri 4-8 ℃ i 22 dana pri -20 ℃. Verificirana je preciznost metode, a ukupna precitnost je iznosila 2,2%, odnosno 1,7% za koncentraciju žučnih kiselina unutar i iznad gornje granice referentnog intervala. Linearnost je verificirana u koncentracijskom području od 3,5-172,1 μmol/l, a verifikacija referentnog intervala za odrasle je zadovoljila kriterije. Ispitivanje interferencije lipemije pokazalo je blagi pozitivan bias (%) koncentracije žučnih kiselina porastom koncentracije triglicerida u serumu. Lipemija uzrokuje nepouzdane rezultate pri koncentraciji SMOFlipid® 20% emulzije 10 g/L, odnosno pri koncentraciji triglicerida iznad 12,4 mmol/L u uzorcima niske inicijalne koncentracije ŽK.
Izrada referentnog intervala za žučne kiseline provodila se a priori pristupom. Određene su koncentracije žučnih kiselina u 116 uzoraka seruma referentnih ispitanica koje su odabrane temeljem prethodno postavljenih kriterija isključenja i uključenja. Statistička obrada rezultata je provedena prema CLSI smjernicama. Referentni interval za populaciju trudnica od 28. do 42. tjedna trudnoće izrađen je neparametrijskom metodom i iznosi od 1,0 do 7,3 μmol/L.

Abstract (english)

Comparison of the patient's laboratory results with reference intervals is one of the most fundamental tools for interpreting laboratory results, making a clinical decision and monitoring the course of the disease. The aim of this study was to introduce a method for determining bile acids into the analytical system, to verify its parameters, and to establish a reference interval for bile acids for the population of pregnant women from the 28th to the 42nd week of pregnancy. Bile acids as a specific biomarker are used to diagnose intrahepatic cholestasis of pregnancy, a disease that usually occurs in the third trimester and manifests itself as pruritus while being potentially fatal for the child.
Verification of the method showed that bile acids are stable in serum samples for 2 days at 20 ℃, 14 days at 4-8 ℃, and 22 days at -20 ℃. The precision study met the criteria. Within-laboratory precision was 2.2% and 1.7% for the concentration of bile acids within the reference range and above the upper limit, respectively. Linearity was verified for the concentration range of 3.5-172.1 μmol/l, and the verification of the reference interval for adults met the criteria. The lipemia interference test showed a positive bias (%) of bile acid concentration with an increase in serum triglyceride concentration. Lipemia causes unreliable results at a SMOFlipid® 20% emulsion concentration of 10 g/L, i.e. at a triglycerides concentration above 12.4 mmol/L in samples with a low initial concentration of bile acids.
Reference interval for bile acids was determined a priori. Total bile acids concentration was determined in 116 serum samples of the reference pregnant women who were selected based on the previously set exclusion and inclusion criteria. Statistical analysis of the results was carried out according to CLSI guidelines. The reference interval of 1.0 to 7.3 μmol/L for the population of pregnant women from the 28th to the 42nd week of pregnancy was determined using the non-parametric method.

• Keywords: referentni interval; žučne kiseline; intrahepatička kolestaza; trudnoća; verifikacija metode; validacija
• Keywords (english): reference interval; bile acids; intrahepatic cholestasis; pregnancy; verification of the method; validation
• Language: croatian
• URN:NBN: urn:nbn:hr:163:473383
• Study programme: Title: Medical biochemistry; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra medicinske biokemije (magistar/magistra medicinske biokemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2022-09-05 15:33:27