Hyperprolactinemia is a frequent neuroendocrinological condition that should be approached in an orderly and integral fashion, starting with a complete clinical history. Once physiological causes such as pregnancy, systemic disorders such as primary hypothyroidism and the use of drugs with dopamine antagonistic actions such as metochlopramide have been ruled out, the most common cause of hyperprolactinemia is a PRL-secreting pituitary adenoma or prolactinoma. Prolactinomas are usually classified as microprolactinomas less than 1 cm or macroprolactinomas larger than 1 cm , which can either be confined or invasive. Macroprolactinomas can also present with symptoms and signs resulting form mass effect of the tumor, such as headaches and visual field defects. Other structural causes of hyperprolactinemia include non-functioning pituitary adenomas and infiltrative disorders, which can interrupt the inhibitory, descending dopaminergic tone. The primary treatment of prolactinomas is pharmacological with dopamine agonists such as cabergoline.
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Lucio Vilar; Luciana A. In the diagnostic approach of hyperprolactinemia three pitfalls or potential confounding problems deserve special attention: pituitary incidentalomas, the hook effect and macroprolactinemia. The hook effect is characterized by the finding of falsely low levels of serum prolactin PRL when two-site immuno-assays are used in diagnosis in patients with very high prolactin levels. This confusion can be avoided by re-measuring the PRL level in such patients at a dilution; PRL levels in samples with the hook effect will then increase dramatically.
It results from the predominance of polimeric PRL also called macroprolactin or big big prolactin that has decreased bioavailability. Therefore, most patients with macroprolactinemia lack classical symptoms of hyperprolactinemia and usually do not need to be treated.
Keywords: Hyperprolactinemia; Diagnostic pitfalls; Pituitary incidentalomas; Macroprolactin; Macroprolactinemia; Hook effect. Da mesma forma, Smith e cols. O efeito gancho ocorre mais comumente quando se usa o IRMA Em um caso recentemente relatado por Frieze e cols. Efeito gancho em um ensaio para PRL foi inicialmente descrito em , por Comtois e cols.
Os casos reportados por Comtois e cols. Entre os pacientes analisados por Hauache e cols. Fideleff e cols. Vilar L, Castellar E. Rio de Janeiro: Medsi, Guidelines for the diagnosis and treatment of hyperprolactinemia. J Reprod Med ;44 12 Suppl Vieira JGH. Arq Bras Endocrinol Metab ; Lindstedt G. Endogenous antibodies against prolactin: a "new" cause of hyperprolactinemia. Eur J Endocrinol ; Sinha YN. Structural variants of prolactin: occurrence and physiological significance.
Endocr Rev ; Polymers of prolactin and their clinical significance. Obstet Gynecol Surv ; Characterization of a large molecular weight prolactin in women with idiopathic hyperprolactinemia and normal menses.
J Clin Endocrinol Metab ; Hatori N, Inagaki C. Anti-prolactin PRL autoantibodies cause asymptomatic hyperprolactinemia: bioassay and clearance studies of PRL-immunoglobulin G complex. Some forms of big-big prolactin behave as a complex of monomeric prolactin with an immunoglobulin G in patients with macroprolactinemia. Maintained fertility in a patient with hyperprolactinemia due to big-big prolactin.
Gadellha MR, Une K. Molitch ME. Disorders of prolactin secretion. Endocrinol Metab Clin ; Mechanism of verapamil calcium channel blockade-induced hyperprolactinemia. Am J Physiol ;EE Increased prolactin levels during reserpine treatment of hypertensive patients.
JAMA ; Effect of methyldopa on prolactin and growth hormone. Br Med J ; Elevated prolactin in pediatric patients on typical and atypical antipsychotics. J Child Adolesc Psychopharmacol ; Prolactin levels and adverse events in patients treated with risperidone. J Clin Psychopharmacol ; Galactorrhoea and hyperprolactinemia associated with protease inhibitors. Lancet ; Misinterpretation of prolactin levels leading to management errors in patients with sellar enlargement.
Am J Med ; In: Melmed S, editor. The pituitary. Blackwell Science: Cambridge. Serum prolactin levels in untreated primary hypothyroidism. Incidence of hyperprolactinemia in patients with Hashimoto's thyroiditis. Endocr J ; Pituitary tumor syndrome and hyperprolactinemia in peripheral hypothyroidism.
Ann Endocrinol Paris ; Reversible hyperthyrotropinemia, hyperthyroxinemia and hyperprolactinemia due to adrenal insufficiency. Is prolactin secreted ectopically? Prolactinoma in wall of ovarian dermoid cyst with hyperprolactinemia. Obstet Gynecol ; Laboratory and clinical experience in 55 patients with macroprolactinemia identified by a simple polyethylene glycol precipitation method. Autoantibody to human prolactin in patients with idiopathic hyperprolactinemia.
Macroprolactinemia as the cause of elevated serum prolactin in men. Macroprolactinemia in childhood and adolescence: a cause of asymptomatic hyperprolactinemia. Horm Res ; Schlechte JA. The Macroprolactin Problem [Editorial]. Screening for macroprolactinaemia may prevent unnecessary pituitary imaging studies.
Clin Endocrinol ; Olukoga A, Kane J. Macroprolactinaemia: validation and application of the polyethylene glycol precipitation test and clinical characterization of the condition. Fahie-Wilson M, Soule S. Macroprolactinaemia: contribution to hyperprolactinaemia in a district general hospital and evaluation of a screening test based on precipitation with polyethylene glycol. Ann Clin Biochem ; Macroprolactinemia revisited: a study on patients. Further evidence that big-big prolactin is preferentially secreted in women with hyperprolactinemia and normal ovarian function.
Fertil Steril ; Asymptomatic hyperprolactinaemia and prolactinoma in the general population-mass screening by paired assays of serum prolactin. Clin Endocrinol Oxf ; Bioactivity of prolactin in a woman with an excess of large molecular size prolactin, persistent hyperprolactinemia, and spontaneous conception.
Frequency of hyperprolactinaemia due to large molecular weight prolactin kDa PRL. Scand J Clin Lab Investig ; Extensive experience and validation of polyethylene glycol precipitation as a screening method for macroprolactinemia. Clin Chem ; Cocaine effects on pulsatile secretion of anterior pituitary, gonadal, and adrenal hormones.
Subclinical hypothyroidism and hyperprolactinemia. Acta Eur Fertil ; Pituitary incidentalomas. Endocrinol Metab Clin North Am ; Vance ML, Thorner M. Evaluation and treatment of galactorrhea. Am Fam Physician ; Galactorrhea: a study of cases, including 48 with pituitary tumors. N Engl J Med ; Correlation of the antibody titers with serum prolactin levels and their clinical course in patients with anti-prolactin autoantibody.
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[Current Diagnosis and Treatment of Hyperprolactinemia]
Lucio Vilar; Luciana A. In the diagnostic approach of hyperprolactinemia three pitfalls or potential confounding problems deserve special attention: pituitary incidentalomas, the hook effect and macroprolactinemia. The hook effect is characterized by the finding of falsely low levels of serum prolactin PRL when two-site immuno-assays are used in diagnosis in patients with very high prolactin levels. This confusion can be avoided by re-measuring the PRL level in such patients at a dilution; PRL levels in samples with the hook effect will then increase dramatically. It results from the predominance of polimeric PRL also called macroprolactin or big big prolactin that has decreased bioavailability.
Hyperprolactinemia is a frequent problem in daily clinical practice.. There are several causes of hyperprolactinemia, the most common of which are medications. Consequently, a detailed history must be taken to guide diagnosis.. A thorough history and physical examination, routine laboratory investigations thyroid—stimulatinghormone determination, and pregnancy test allow can rule out all causes of hyperprolactinemia except hypothalamus-pituitary disease.. When no evident cause of secondary hyperprolactinemia is found, hypothalamus-pituitary magnetic resonance imaging MRI should be performed and patients should be diagnosed with idiopathic hyperprolactinemia only when MRI is negative.. Treatment of secondary hyperprolactinemia should be etiologic.. Medical therapy with dopamine agonists is currently the treatment of choice for prolactinomas and idiopathic hyperprolactinemia..