RESUMEN
Syndrome of inappropriate antidiuretic hormone secretion (SIADH) results in impaired water excretion and consequent water intoxication and hyponatremia. In patients with cancer, SIADH is most commonly driven by ectopic ADH production, a paraneoplastic syndrome frequently seen in small cell lung cancer. A 63 year old male presented with loss of appetite, vomiting and hiccups. No abnormalities were detected on physical examination. Upper gastrointestinal endoscopy showed a proliferative growth in the stomach and histopathology report confirmed gastric adenocarcinoma. His laboratory investigations revealed low serum sodium and further work up for SIADH confirmed the diagnosis. The patient was treated with hypertonic saline and he improved symptomatically. He was subsequently treated with two cycles of capecitabine and oxaliplatin. The patient was asymptomatic and maintained a serum sodium in the range of 120 to 130 mEq/L, with a serum sodium of 127 mEq/L on follow up.
RESUMEN
Hombre de 54 años con antecedentes de enfermedad de Cushing 32 años antes de la consulta. Ingresó por edemas asociados a astenia y adinamia. En el laboratorio se constató hipopotasemia y alcalosis metabólica. Se realizó diagnóstico humoral de síndrome de Cushing secundario a secreción ectópica de hormona adrenocorticotropa (ACTH). En la tomografía de tórax se halló un tumor de 3 × 3 cm en el mediastino anterior. La anatomía patológica de la pieza quirúrgica fue compatible con un carcinoide tímico. Este paciente sufrió en dos oportunidades un síndrome de Cushing, la primera por enfermedad (adenoma hipofisiario) y la segunda vez por secreción ectópica de ACTH (SEA) una asociación no descripta, en nuestro conocimiento, en la literatura médica.
A 54-year-old man, with a history of Cushing’s disease diagnosed 32 years earlier, presented with edema, asthenia and general malaise. Abnormal laboratory studies depicted hypokalemia and metabolic alkalosis. A CT scan of the chest revealed a 3 × 3 cm tumor in the anterior mediastinum. The pathology was consistent with a thymic carcinoid. These findings led to a diagnosis of biochemical Cushing’s syndrome secondary to ectopic secretion of ACTH. Thus, this patient suffered twice of Cushing’s syndrome. The first instance was the consequence of an ACTH - secreting pituitary adenoma and the second of an ectopic secretion of ACTH. To the best of our knowledge this is the first such case reported in the medical literature.