Measurement of melatonin in body fluids: Standards, protocols and procedures

Abstract: The circadian rhythm of melatonin in saliva or plasma, or of the melatonin metabolite 6‐ sulphatoxymelatonin in urine, is a defining feature of suprachiasmatic nucleus function, the endogenous oscillatory pacemaker. These measurements are useful to evaluate problems related to the onset or offset of sleep and for assessing phase delays or advances of rhythms in entrained individuals. Additionally, they have become an important tool for psychiatric diagnosis, its use being recommended for phase typing in patients suffering from sleep and mood disorders. Thus, the development of sensitive and selective methods for the precise detection of melatonin in tissues and fluids of animals emerges as necessary. Due to its low concentration and the co‐existence of many other endogenous compounds in blood, the determination of melatonin has been an analytical challenge. This review discusses current methodologies employed for detection and quantification of melatonin in biological fluids and tissues

Tratamento de macroprolactinoma com cabergolina em adolescente An adolescent patient with prolactinoma treated with cabergoline

OBJETIVO: Relatar um caso de macroprolactinoma diagnosticado em adolescente e tratado com cabergolina. DESCRIÇÃO DO CASO: Paciente do sexo feminino, 15 anos, iniciou quadro clínico aos dez anos, com cefaleia, obesidade e não havia apresentado menarca ao diagnóstico. A dosagem sérica inicial de prolactina foi de 2492ng/mL (valor de referência: 19-25ng/mL). A ressonância nuclear magnética de crânio evidenciou formação expansiva selar e suprasselar compatível com macroadenoma hipofisário sem compressão do quiasma óptico. Seis meses após o início do tratamento com cabergolina, houve queda significativa dos níveis séricos de prolactina para 87,7ng/mL, com redução de 76% no tamanho da lesão e melhora sintomática. COMENTÁRIOS: A ocorrência dos prolactinomas é rara na infância e na adolescência, mas o seu comportamento pode ser mais agressivo. O diagnóstico precoce e o manejo adequado do caso são importantes para um bom prognóstico.<br>OBJECTIVE: To report a teenager with macroprolactinoma treated with cabergoline. CASE DESCRIPTION: A 15-year old female adolescent reported the onset of headaches and obesity since ten years old. At diagnosis amenorrhea was not present. The serum level of prolactin was initially 2492ng/mL (reference values: 19-25ng/mL). Magnetic resonance images of the skull revealed an expansive sellar and suprasellar pituitary macroadenoma without optical chiasmal compression. Six months after starting treatment with cabergoline, there was a significant decrease of prolactin levels to 87.7 ng/mL, with a 76% reduction in the lesion size and she reported improvement of the symptoms. COMMENTS: In childhood and adolescence, prolactinomas are rare, but when they occur the clinical course is more aggressive. Early diagnosis and proper management of the disease are important for a good prognosis