3 Yaşındaki Bir Atta Tiroid Adenomunun Klinik Belirtileri ve Tanısı

Abstract

Atlarda hipertiroidizm, zayıflama, taşipne, agresyon, iştahta değişim ve kaşeksi gibi çeşitli bulgulara sebep olan, genç atlarda nadir bir bozukluktur. Bu olgu sunumunda, tiroid adenomunun klinik tablosu ve tanısında kullanılan metotlar sunuldu. 3 yaşlı erkek Safkan atın dengeli besleme ve iştaha rağmen kilo kaybettiği ve agresifleştiği öğrenildi. İnspeksiyon sırasında larinksin kaudalinde, sol tarafta, palpe edilebilir, ağrısız ve hareketli bir kitle belirlendi. Daha ileri tanı için hemogram, serum biyokimyası, idrar dipstick analizi ve ultrasonografik muayenesi yapıldı. Serum biyokimyasında HDL, LDH, trigliserit, AST, direkt bilirubin, kreatin kinaz ve fT3 düzeyleri yüksek; TSH, fT4 ve ferritin düzeyleri ise düşük bulundu. Ultrasonografik muayenede ise sol tiroid dokusu 2.83 cm x 4.81 cm boyutundaydı. Aspiratın mikroskobik muayenesinde değişken boyutlarda küboidal epitel hücreleri ile çevrelenmiş sitoplazmadan zengin foliküller gözlendi. Bazı foliküllerde dilatasyon gözlenirken bazıları küçük hatta atrofikti. Sonuç olarak elde edilen yüksek fT3 ile düşük TSH düzeyleri, bezin aşırı aktif olduğunu, dolaşımdaki tiroid hormonu seviyesinin yüksek olduğu ve epifiz bezinin feedback mekanizması ile daha az TSH ürettiği, tüm bu durumun hipertiroidizmi gösterdiği gerçeği ile uyumluydu. Ayrıca tiroid adenomunun genç atlarda da görülebileceği, klinik semptomlara sebep olabileceği, ultrasonografik muayene, ince iğne aspirasyon tekniği ile alınan aspiratın mikroskobik muayenesi ile birlikte kapsamlı serum biyokimyası analizinin tanı için yeterli olduğu kanısına varıldı.

Keywords

• İnce iğne aspirasyonu
• Serum biyokimyası
• Tanı
• Ultrason

Clinical Manifestation and Diagnosis of a Thyroid Adenoma in a 3-year-old Horse

Abstract

Hyperthyroidism in horses is a rare disorder in young horses that causes diverse findings such as weight loss, tachypnea, aggression, change in appetite and cachexia. In this report, the clinical manifestation and methods that used in the diagnosis of thyroid adenoma are presented. It was learned that a 3-year-old male Thoroughbred horse became aggressive and had been losing weight despite an adequate diet and appetite. During the inspection, a palpable, painless and moving mass was detected caudal to the larynx, on the left side. For further diagnosis, hemogram, serum biochemistry, urine dipstick analysis and ultrasonographic examination were performed. In serum biochemistry, high HDL, LDH, triglyceride, AST, direct bilirubin, creatine kinase and fT3; low TSH, fT4 and ferritin levels were determined. Ultrasonographic examination revealed that the left thyroid tissue was 2.83 cm x 4.81 cm in size. In the microscopic examination of the aspirate, it was observed that follicles were rich in cytoplasm and surrounded by cuboidal epithelial cells of varying sizes. Dilatation was observed in some follicles, while others were small or even atrophic. As a result, high fT3 and low TSH levels were consistent with the fact that the gland was overactive, the circulating thyroid hormone level was high, and the pineal gland produced less TSH by the feedback mechanism, all of which indicated hyperthyroidism. In addition, it was concluded that thyroid adenoma can also be seen in young horses, may cause clinical symptoms, ultrasonographic examination, microscopic examination of the aspirate and comprehensive serum biochemistry analysis are sufficient for diagnosis.

Keywords

• Fine needle aspiration
• Serum biochemistry
• Diagnosis
• Ultrasound

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