Seyit Ahmet EROL, Nur Gözde KULHAN, Oğuzhan GÜNENC

Fetal büyüme kısıtlılığı ile komplike gebeliklerde fetal timus boyutunun değerlendirilmesi

Amaç: Fetal büyüme kısıtlılığı (FBK) ile komplike gebeliği olan kadınlarda timik-torasik oran (TTR) kullanarak fetal timus boyutunu değerlendirmek ve olumsuz perinatal sonuçlarla olan ilişkisini belirlemek. Gereçler ve Yöntem: Bu prospektif çalışmaya FBK ile komplike toplam 35 gebe kadın ile benzer demografik özellikte sağlıklı toplam 42 gebe kadın dahil edildi. FBK grubunda, patolojik doppler akım parametreleri olan umbilikal arterde end-diyastolik akım kaybı (EDAK) ve serebroplasental oran (SPO) <1 olan ve tahmini fetal ağırlığı (TFA) <3. persantil olan olgular ayrıca kayıt altına alındı. Gruplar arasında demografik özellikler, klinik ve sonografik özellikler ve fetal TTR açısından karşılaştırmalar yapıldı. Elde edilen verilerin istatistiksel analizinde, gruplar arası ortanca (median) değerlerin ve kategorik değişkenlerin karşılaştırılmalarında Mann-Whitney U ve Fisher’s Exact testleri kullanıldı. Fetal TTR ile olumsuz perinatal sonuçlar arasındaki ilişki Spearman korelasyon katsayısı ile araştırıldı. P<0.05 değeri istatistiksel olarak anlamlı kabul edildi. Bulgular: TFA <3. persantil, oligohidramniyoz, patolojik doppler akımı dışındaki olumsuz perinatal sonuçlar ve diğer parametreler her iki grupta da benzerdi (p>0.05). Fetal TTR'nin FBK grubunda kontrol grubuna göre anlamlı derecede daha düşük olduğu belirlendi (0.37±0.02 [0.33-0.42] ve 0.40±0.02 [0.36-0.45], p<0.001, sırasıyla). Fetal TTR ile TFA <3. persantil, patolojik doppler akımı (EDAK ve SPO <1) arasında istatistiksel olarak anlamlı, orta düzeyde negatif bir korelasyon saptandı (r= -0.703, r= -0.588, r= -0.383, r= -0.418 ve p<0.001, p<0.001, p=0.023, p=0.012, sırasıyla). Sonuç: FBK ile komplike gebeliklerde fetal TTR ölçümünün değerlendirildiği ilk çalışmadır. Düşük fetal TTR, FBK ile fetal timik involusyon ilişkisini desteklemektedir. Bununla birlikte, olumsuz perinatal sonuçların öngörüsünde fetal TTR bir sonografik indikatör olabilir.

Anahtar Kelimeler:

Fetal büyüme kısıtlılığı, timik-torasik oran, ultrason

Evaluation of fetal thymus size in pregnancies complicated with fetal growth restriction

Aim: To evaluate fetal thymus size using the thymic-thoracic ratio (TTR) in women with a pregnancy complicated with fetal growth restriction (FGR) and to assess the relationship with adverse perinatal outcomes. Materials and Method: A total of 35 pregnant women with FGR and 42 healthy pregnant women with similar demographic characteristics were included in this prospective study. In the FGR group, cases with pathological doppler flow parameters of absent end-diastolic flow (AEDF) in an umbilical artery and cerebroplacental ratio (CPR) <1 and estimated fetal weight (EFW) <3rd percentile were also recorded. The groups were compared in terms of demographic features, clinical and sonographic characteristics and fetal TTR. In the statistical analysis of the data obtained, the Mann-Whitney U and Fisher's Exact tests were used to compare the median values of the groups and categorical variables. The association between fetal TTR and adverse perinatal outcomes was investigated using Spearman's correlation coefficient. The level of statistical significance was set at p<0.05. Results: Other than the adverse perinatal outcomes of EFW <3rd percentile, oligohydramnios, pathological doppler flow, all the other parameters were similar in both groups (p>0.05). The fetal TTR was determined to be significantly lower in the FGR group than in the control group (0.37±0.02 [0.33-0.42] and 0.40±0.02 [0.36-0.45], p<0.001, respectively). A statistically significant, negative moderate correlation was determined between fetal TTR and the EFW <3rd percentile, pathological doppler flow (AEDF and CPR<1) (r= -0.703, r= -0.588, r= -0.383, r= -0.418 and p<0.001, p<0.001, p=0.023, p=0.012, respectively). Conclusion: This is the first study to have evaluated the fetal TTR measurement in FGR-complicated pregnancies. A lower fetal TTR supports the relationship between FGR and fetal thymic involution. Moreover, fetal TTR might be a sonographic indicator for predicting adverse perinatal outcomes.

Keywords:

Fetal growth restriction, thymic-thoracic ratio, ultrasound,

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1. Martins JG, Biggio JR, Abuhamad A. Society for Maternal-Fetal Medicine Consult Series #52: Diagnosis and management of fetal growth restriction: (Replaces Clinical Guideline Number 3, April 2012). Am J Obstet Gynecol. 2020;223(4):B2-B17.
2. ACOG Practice Bulletin No. 204: Fetal Growth Restriction. Obstet Gynecol. 2019;133(2):e97-e109.
3. Goncu Ayhan S, Oluklu D, Sinaci S, Atalay A, Erol SA, Ozden Tokalioglu E, et al. Fetal Thymus Size in Pregnant Women with COVID-19 Infection. Gynecology Obstetrics & Reproductive Medicine. 2021;27(2):84-8.
4. Gordon J, Manley NR. Mechanisms of thymus organogenesis and morphogenesis. Development. 2011;138(18):3865-78.
5. Cromi A, Ghezzi F, Raffaelli R, Bergamini V, Siesto G, Bolis P. Ultrasonographic measurement of thymus size in IUGR fetuses: a marker of the fetal immunoendocrine response to malnutrition. Ultrasound Obstet Gynecol. 2009;33(4):421-6.
6. Di Naro E, Cromi A, Ghezzi F, Raio L, Uccella S, D'Addario V, et al. Fetal thymic involution: a sonographic marker of the fetal inflammatory response syndrome. Am J Obstet Gynecol. 2006;194(1):153-9.
7. Mastrolia SA, Erez O, Loverro G, Di Naro E, Weintraub AY, Tirosh D, et al. Ultrasonographic approach to diagnosis of fetal inflammatory response syndrome: a tool for at-risk fetuses? Am J Obstet Gynecol. 2016;215(1):9-20.
8. Ghalandarpoor-Attar SN, Borna S, Ghalandarpoor-Attar SM, Hantoushzadeh S, Khezerdoost S, Ghotbizadeh F. Measuring fetal thymus size: a new method for diabetes screening in pregnancy. J Matern Fetal Neonatal Med. 2020;33(7):1157-61.
9. Ekin A, Gezer C, Taner CE, Solmaz U, Gezer NS, Ozeren M. Prognostic Value of Fetal Thymus Size in Intrauterine Growth Restriction. J Ultrasound Med. 2016;35(3):511-7.
10. Goncu Ayhan S, Turgut E, Oluklu D, Ozden Tokalioglu E, Menekse Beser D, Moraloglu Tekin O, et al. Influence of Covid-19 infection on fetal thymus size after recovery. J Perinat Med. 2022;50(2):139-43.
11. Karl K, Heling KS, Sarut Lopez A, Thiel G, Chaoui R. Thymic-thoracic ratio in fetuses with trisomy 21, 18 or 13. Ultrasound Obstet Gynecol. 2012;40(4):412-7.
12. Available from: https://konyasehir.saglik.gov.tr/TR-579494/dogum-istatistikleri.html.
13. Faul F, Erdfelder E, Buchner A, Lang AG. Statistical power analyses using G*Power 3.1: tests for correlation and regression analyses. Behav Res Methods. 2009;41(4):1149-60.
14. Chaoui R, Heling KS, Lopez AS, Thiel G, Karl K. The thymic-thoracic ratio in fetal heart defects: a simple way to identify fetuses at high risk for microdeletion 22q11. Ultrasound Obstet Gynecol. 2011;37(4):397-403.
15. Savino W, Dardenne M, Velloso LA, Dayse Silva-Barbosa S. The thymus is a common target in malnutrition and infection. Br J Nutr. 2007;98 Suppl 1:S11-6.
16. Olearo E, Oberto M, Oggè G, Botta G, Pace C, Gaglioti P, et al. Thymic volume in healthy, small for gestational age and growth restricted fetuses. Prenat Diagn. 2012;32(7):662-7.
17. Velloso LA, Savino W, Mansour E. Leptin action in the thymus. Ann N Y Acad Sci. 2009;1153:29-34.
18. Causevic M, Mohaupt M. 11beta-Hydroxysteroid dehydrogenase type 2 in pregnancy and preeclampsia. Mol Aspects Med. 2007;28(2):220-6.
19. Varga I, Pospisilova V, Jablonska-Mestanova V, Galfiova P, Polak S. The thymus: picture review of human thymus prenatal development. Bratisl Lek Listy. 2011;112(7):368-76.
20. Edwards A, Springett A, Padfield J, Dorling J, Bugg G, Mansell P. Differences in post-mortem findings after stillbirth in women with and without diabetes. Diabet Med. 2013;30(10):1219-24.
21. Dörnemann R, Koch R, Möllmann U, Falkenberg MK, Möllers M, Klockenbusch W, et al. Fetal thymus size in pregnant women with diabetic diseases. J Perinat Med. 2017;45(5):595-601.
22. Mohamed N, Eviston DP, Quinton AE, Benzie RJ, Kirby AC, Peek MJ, et al. Smaller fetal thymuses in pre-eclampsia: a prospective cross-sectional study. Ultrasound Obstet Gynecol. 2011;37(4):410-5.
23. Eviston DP, Quinton AE, Benzie RJ, Peek MJ, Martin A, Nanan RK. Impaired fetal thymic growth precedes clinical preeclampsia: a case-control study. J Reprod Immunol. 2012;94(2):183-9.
24. Yinon Y, Zalel Y, Weisz B, Mazaki-Tovi S, Sivan E, Schiff E, et al. Fetal thymus size as a predictor of chorioamnionitis in women with preterm premature rupture of membranes. Ultrasound Obstet Gynecol. 2007;29(6):639-43.
25. El-Haieg DO, Zidan AA, El-Nemr MM. The relationship between sonographic fetal thymus size and the components of the systemic fetal inflammatory response syndrome in women with preterm prelabour rupture of membranes. Bjog. 2008;115(7):836-41.
26. Gur EB, Gur MS, Ince O, Kasap E, Genc M, Tatar S, et al. Vitamin D deficiency in pregnancy may affect fetal thymus development. Ginekol Pol. 2016;87(5):378-83.