Serum tirotropin için biyolojik varyasyon bileşenleri ve kalite spesifikasyonlarının belirlenmesi

Year 2020, Volume: 13 Issue: 2, 284 - 289, 14.05.2020

Müjgan Ercan , Emiş Deniz Akbulut Adnan Kirmit

https://doi.org/10.31362/patd.647255

Abstract

Amaç:
Serum tiroid hormon düzeyleri tiroid hastalıklarının tanı ve takibinde
kullanılır. Bu çalışma serum tirotropin (TSH) için biyolojik varyasyonu (BV)
hesaplanması ve değerlendirilmesini amaçlamaktadır.

Gereç ve yöntemler:
Kan örnekleri, sekiz gönüllüden (dört kadın, dört erkek; yaşları 20-35 arasında
değişen) beş hafta boyunca, haftalık olarak alındı. Serum TSH seviyeleri Abbott
Architect ci8200  immunassay cihazında
ölçüldü ve Biyolojik varyasyon (BV) hesaplamaları Fraser’ın yöntemine göre
nested ANOVA testi kullanıldı.

Bulgular: Serum TSH için hesaplanan analitik
varyasyon (CV_A), birey içi BV (CV_I), bireylerarası BV (CV_G),  bireysellik indeksi (II) ve referans değişim
değeri (RCV) değerleri sırasıyla  %
5.4,  % 26.2,  % 26.9, 
0.99 ve % 74.2 idi.  Belirsizlik, bias ve izin verilen toplam hata (TEA)
için istenen performans hedefleri sırasıyla <% 13.1, <% 6.7 ve <% 28.3
idi.

Sonuç: BV
veri tabanındaki (CV_I =% 19.3 ve CV_G =% 24.6) sonuçlar
ile karşılaştırdığımızda Serum TSH için elde ettiğimiz CV_I ve CV_G
değerleri daha yüksek olduğunu tespit ettik. TSH’ın takibi sırasında sonuçların
değerlendirilmesi için hesaplanan düşük II, TSH bireyselliğinin daha belirgin
olduğunu ve toplum bazlı referans aralıklarının daha az kullanışlı olduğunu
gösterir.

Keywords

TSH, biyolojik varyasyon, birey-içi biyolojik varyasyon, bireyler-arası biyolojik varyasyon, referans değişim değeri

Determination of biological variation components and quality specifications for serum thyrotropin

Abstract

Purpose: Serum thyroid hormone levels are used in the diagnosis and follow-up
of thyroid disorders. The present study aims calculation and
evaluation of biological variation (BV) measures for serum thyrotropin (TSH).

Materials and Methods:
Blood
samples were collected from eight volunteers (four women, four men; ages
ranging between 20 to 35) weekly throughout five weeks. Serum TSH level was
measured on Architect ci8200 immunoassay system and BV estimates were obtained
using nested ANOVA test according to the method of Fraser.

 Results:
Calculated analytical variation (CV_A), within-subject BV (CV_I),
between-subject BV (CV_G), index of individuality (II) and reference
change value (RCV) for serum TSH were 5.4%, 26.2%, 26.9%, 0.99 and 74.2%,
respectively. Desirable performance goals for imprecision,
bias and total allowable error (TE_A) were <13.1% , <6.7% and <28.3% respectively.

Conclusion: When we compared our results with the results from BV database (CV_I=%19.3
and CV_G=%24.6) for serum TSH we found out higher CV_I and CV_G
values. Calculated low II meaning
marked individuality indicates that population-based reference values are less
useful for the evaluation of results while monitoring serum TSH.

Keywords

TSH, biological variation, intra-individual variation, inter-individual variation, referance change value

References

• 1. Pirahanchi Y, Jialal I. Physiology, Thyroid Stimulating Hormone (TSH). StatPearls [Internet]: StatPearls Publishing; 2019.
• 2. Stockigt J. Assessment of thyroid function: towards an integrated laboratory--clinical approach. The Clinical biochemist Reviews. 2003;24(4):109-22.
• 3. Baloch Z, Carayon P, Conte-Devolx B, Demers LM, Feldt-Rasmussen U, Henry JF, et al. Laboratory medicine practice guidelines. Laboratory support for the diagnosis and monitoring of thyroid disease. Thyroid : official journal of the American Thyroid Association. 2003;13(1):3-126.
• 4. Demers LM, Spencer CA. Laboratory medicine practice guidelines: laboratory support for the diagnosis and monitoring of thyroid disease. Clinical endocrinology. 2003;58(2):138-40.
• 5. Browning MC, Ford RP, Callaghan SJ, Fraser CG. Intra- and interindividual biological variation of five analytes used in assessing thyroid function: implications for necessary standards of performance and the interpretation of results. Clinical chemistry. 1986;32(6):962-6.
• 6. Fraser CG. Inherent biological variation and reference values. Clinical chemistry and laboratory medicine. 2004;42(7):758-64.
• 7. Perich C, Minchinela J, Ricos C, Fernandez-Calle P, Alvarez V, Domenech MV, et al. Biological variation database: structure and criteria used for generation and update. Clinical chemistry and laboratory medicine. 2015;53(2):299-305.
• 8. Maes M, Mommen K, Hendrickx D, Peeters D, D'Hondt P, Ranjan R, et al. Components of biological variation, including seasonality, in blood concentrations of TSH, TT3, FT4, PRL, cortisol and testosterone in healthy volunteers. Clinical endocrinology. 1997;46(5):587-98.
• 9. Ankrah-Tetteh T, Wijeratne S, Swaminathan R. Intraindividual variation in serum thyroid hormones, parathyroid hormone and insulin-like growth factor-1. Annals of clinical biochemistry. 2008;45(Pt 2):167-9.
• 10. Erden G, Barazi AÖ, Tezcan G, Yildirimkaya M. Biological variation and reference change values of TSH, free T3, and free T4 levels in serum of healthy Turkish individuals. Turkish Journal of Medical Sciences. 2008;38(2):153-8.
• 11. Ricos C, Arbos MA. Quality goals for hormone testing. Annals of clinical biochemistry. 1990;27 ( Pt 4):353-8.
• 12. Fraser CG, Harris EK. Generation and application of data on biological variation in clinical chemistry. Critical reviews in clinical laboratory sciences. 1989;27(5):409-37.
• 13. Fraser CG. Biological variation: from principles to practice: Amer. Assoc. for Clinical Chemistry; 2001.