Tirotoksikozun Nadir Bir Nedeni: TSH Salgılayan Hipofiz Adenomu

Abstract

Tiroid stimulan hormon (TSH) salgılayan hipofiz adenomu (TSHoma) tirotoksikozun nadir görülen sebeplerinden biridir. Tanı genellikle uygunsuz TSH yüksekliğinin araştırılması ya da hipofizer insidentalomanın tetkiki sırasında konulmaktadır. Olgumuz bilinen poliskistik over sendromu olan 26 yaşında kadın hasta olup altı aydır olan titreme, terleme ve baş ağrısı yakınmalarıyla kliniğimize başvurdu. Laboratuvar analizlerinde serum serbest T3 ve T4 düzeyi yüksek iken TSH düzeyi normal sınırlarda saptandı. Seks hormonu bağlayıcı globülin (SHBG) düzeyi normal sınırlardaydı Manyetik rezonans görüntüleme sonucunda hipofiz bezinde makradenom izlendi. TRH uyarı testine TSH yanıtı saptanmadı. TSHoma tanısı alan hastada preoperatif oktreotid ve metimazol tedavisi ile ötiroidizm sağlandıktan sonra hipofiz cerrahisi uygulandı. Cerrahi materyalin histopatolojik incelemesinde fibrotik değişikliklerle birlikte prolaktin ile pozitif, TSH ile negatif boyanma izlendi. Bu olgu sunumunda SHBG düzeyi normal ve TSH boyaması negatif olmasına rağmen uygunsuz TSH salınımı nedeniyle TSHoma tanısı alan bir hastayı sunmayı amaçladık.

Keywords

• Tiroid stimulan hormon salgılayan hipofizer adenom
• tirotoksikoz
• hipertiroidi
• oktreotid

A Rare Cause of Thyrotoxicosis: TSH-Secreting Pituitary Adenoma

Abstract

Thyroid-stimulating hormone (TSH) secreting pituitary adenoma (TSHoma) is one of the rare causes of thyrotoxicosis. The diagnosis is usually made during investigating inappropriate TSH elevation or pituitary incidentaloma. Our patient, a 26-year-old female patient, known to have polycystic ovary syndrome, was admitted to our clinic with complaints of tremor, sweating, and headache for six months. Laboratory analysis showed serum free T3 and T4 levels were elevated, while TSH levels were within normal limits. Sex hormone binding globulin (SHBG) level was within normal limits. Macroadenoma was observed in the pituitary gland at magnetic resonance imaging. TSH secretion did not increase much in response to the thyrotropin-releasing hormone. The patient was diagnosed with TSHoma, and pituitary surgery was performed after euthyroidism was achieved with preoperative octreotide and methimazole treatment. Positive staining with prolactin and negative staining with TSH were observed along with fibrotic changes in the histopathological examination of the surgical material. We aimed to present a patient diagnosed with TSHoma due to inappropriate TSH secretion, although her SHBG level was normal and TSH staining was negative in the current case report.

Keywords

• Thyroid stimulating hormone secreting pituitary adenoma
• thyrotoxicosis
• hyperthyroidism
• octreotide

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