Akromegali
Özet
Akromegali, çoğunlukla hipofiz bezinin ön lobundaki somatotrop hücreli adenomlardan kaynaklanan, aşırı büyüme hormonu (GH) salınımıyla karakterize nadir ve kronik endokrin bir hastalıktır. Bulguların yavaş ilerlemesi tanı süresini 4-10 yıl geciktirmekte, hastalık genellikle 40 yaş civarında ve her iki cinsiyette eşit sıklıkta teşhis edilmektedir. En belirgin klinik özellikler el ve ayaklarda büyüme, yüz hatlarında kabalaşma, prognatizm ve ses kalınlaşmasıdır. Aşırı hormon salgısı makrodokularda kalınlaşmaya yol açarak karpal tünel sendromu, artralji, uyku apnesi ve hipertansiyon gibi çoklu sistemik komplikasyonları beraberinde getirir. Ayrıca insülin direnci, diyabetes mellitus ve kolon polipleri riskinde artış görülür. Tanı aşamasında ilk olarak serum insülin benzeri büyüme faktörü-1 (IGF-1) seviyesi ölçülür; yüksek veya şüpheli değer varlığında ise oral glukoz tolerans testi (OGTT) ile GH supresyon testi uygulanarak tanı kesinleştirilir. Tümörün lokalizasyonu ve çevre dokularla ilişkisi sella manyetik rezonans (MR) görüntüleme ile değerlendirilir. Birinci basamak tedavi seçeneği transsfenoidal cerrahidir. Cerrahiyle tam remisyon sağlanamayan ya da operasyonun riskli olduğu hastalarda medikal tedaviler (dopamin agonistleri, somatostatin reseptör ligandları, pegvisomant) ve stereotaktik radyoterapi tercih edilir. Tedavinin temel amacı GH ve IGF-1 seviyelerini normalleştirerek mortaliteyi azaltmaktır.
Acromegaly is a rare, chronic endocrine disorder characterized by excessive growth hormone (GH) secretion, mostly arising from a somatotroph adenoma in the anterior pituitary gland. Due to the insidious onset of signs and symptoms, diagnosis is often delayed by 4 to 10 years, with a mean age at diagnosis of approximately 40 years, affecting men and women equally. The most prominent clinical features include enlargement of the hands and feet, coarsening of facial features, prognathism, and deepening of the voice. GH hypersecretion leads to soft tissue thickening, resulting in systemic complications such as carpal tunnel syndrome, arthralgia, sleep apnea, and hypertension. Additionally, insulin resistance, diabetes mellitus, and a high prevalence of colon polyps are observed. Biochemical screening begins with measuring serum insulin-like growth factor-1 (IGF-1) levels, followed by an oral glucose tolerance test (OGTT) for GH suppression to confirm the diagnosis if IGF-1 is elevated. Tumor localization and structural relationships are evaluated using sella magnetic resonance imaging (MRI). Transsphenoidal surgery is the preferred first-line treatment. For patients who do not achieve remission post-surgery or for whom surgery is contraindicated, medical therapies (dopaminergic agonists, somatostatin receptor ligands, pegvisomant) and stereotactic radiotherapy are utilized to control hormone levels and reduce long-term mortality.
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