RESUMEN
Cortisol is a hydrophobic molecule that is largely bound to corticosteroid-binding globulin (CBG) in the circulation. In the assessment of adrenal insufficiency, many clinicians measure a total serum cortisol level, which assumes that CBG is present in normal concentrations and with a normal binding affinity for cortisol. CBG concentration and affinity are affected by a number of common factors including oral contraceptive pills (OCPs), fever and infection, as well as rare mutations in the serine protease inhibitor A6 (SERPINA6) gene, and as such, total cortisol levels might not be the ideal way to assess adrenal function in all clinical circumstances. This paper reviews the limitations of immunoassay and liquid chromatography-tandem mass spectrometry (LC-MS/MS) in the measurement of total cortisol, the challenges of measuring free serum cortisol directly as well as the difficulties in calculating an estimated free cortisol from total cortisol, CBG and albumin concentrations. Newer approaches to the evaluation of adrenal insufficiency, including the measurement of cortisol and cortisone in the saliva, are discussed and a possible future role for these tests is proposed.
Asunto(s)
Insuficiencia Suprarrenal/diagnóstico , Endocrinología/métodos , Hidrocortisona/sangre , Sistema Hipotálamo-Hipofisario/fisiopatología , Pediatría/métodos , Sistema Hipófiso-Suprarrenal/fisiopatología , Transcortina/metabolismo , Insuficiencia Suprarrenal/genética , Insuficiencia Suprarrenal/metabolismo , Insuficiencia Suprarrenal/fisiopatología , Algoritmos , Niño , Cortisona/metabolismo , Humanos , Hidrocortisona/química , Hidrocortisona/metabolismo , Hidrocortisona/orina , Interacciones Hidrofóbicas e Hidrofílicas , Mutación , Guías de Práctica Clínica como Asunto , Reproducibilidad de los Resultados , Saliva/metabolismo , Albúmina Sérica Humana/análisis , Transcortina/química , Transcortina/genéticaRESUMEN
An 8-year-old girl with idiopathic central precocious puberty experienced multiple episodes of anaphylaxis after receiving a goserelin acetate implant. She was hospitalized and treated with epinephrine, antihistamine, and corticosteroids. The goserelin implant was surgically excised; however, anaphylactic symptoms continued for 4 days after excision. Less severe systemic symptoms recurred 6 weeks after removal; these were possibly due to leakage of the depot drug into subcutaneous tissues. It was noted that 3 years earlier, the patient had developed a similar, milder systemic allergic reaction to leuprolide acetate that required treatment with oral prednisone and antihistamines. Intradermal testing yielded positive results for leuprolide. Gonadotropin-releasing hormone (GnRH) analogs, including leuprolide acetate and goserelin acetate, are commonly prescribed for patients with prostatic carcinoma, endometriosis, and precocious puberty. A literature review identified a single case report of a systemic hypersensitivity reaction involving goserelin acetate and several reports of systemic hypersensitivity reactions associated with leuprolide acetate. We found no reports of systemic reactions to GnRH analogs in pediatric patients. Clinicians should be aware of the potential association of GnRH analogs with systemic reactions. They should also recognize that recurrent anaphylaxis may occur due to the long half-life of these therapeutic agents in tissue.