|Year : 2018 | Volume
| Issue : 2 | Page : 107-110
Idiopathic hyperprolactinemia with tumoral prolactin levels
Nadia Belmahi1, Houda Salhi1, Said Boujraf2, Hanan El Ouahabi1
1 Department of Endocrinology and Metabolism, University Hospital of Fez, Fes, Morocco
2 Department of Biophysics and Clinical Magnetic Resonance Imaging Methods, Faculty of Medicine and Pharmacy, University of Fez, Fes, Morocco
|Date of Web Publication||22-Feb-2019|
Department of Biophysics and Clinical Magnetic Resonance Imaging Methods, University of Fez, BP 1893, Km 2.200, Sidi Hrazem Road, Fes 30000
Source of Support: None, Conflict of Interest: None
The causes of hyperprolactinemia are varying, from physiological to pharmacological and pathological causes; but some cases are classified as “idiopathic” because of unknown causes. We describe a 29-year-old woman who presented to our department with galactorrhea and secondary amenorrhea. She had no clinical features of hypopituitarism and was not taking any medication. On physical examination, she had bilateral galactorrhea. Prolactin (PRL) level was high, up to 200 ng/ml, and other pituitary and thyroid indices were normal, including testing for macroprolactinemia. Pituitary magnetic resonance imaging was normal; and thoraco-abdominopelvic tomography was performed with no abnormalities detected. Cabergoline was started at the dose 0.5 mg/week. Galactorrhea disappeared, the menstrual cycle had become regular, and PRL level decreased to 26 ng/ml. Should all causes of hyperprolactinemia be ruled out and pituitary imaging revealed as negative, idiopathic hyperprolactinemia is therefore diagnosed. In symptomatic patients, treatment with dopaminergic agonists is indicated.
Keywords: Dopaminergic agonists, idiopathic hyperprolactinemia, tumor
|How to cite this article:|
Belmahi N, Salhi H, Boujraf S, El Ouahabi H. Idiopathic hyperprolactinemia with tumoral prolactin levels. Onco Fertil J 2018;1:107-10
| Introduction|| |
Hyperprolactinemia is the most common endocrine disorder of the hypothalamo–pituitary axis. The causes of hyperprolactinemia include physiological, pharmacological, and pathological causes. However, some cases are classified as “idiopathic hyperprolactinemia” because the causes are unknown. This article presents a case of idiopathic hyperprolactinemia with tumoral prolactin (PRL) levels and normal pituitary magnetic resonance imaging (MRI).
| Case Report|| |
We describe a 29-year-old woman who presented to our department with galactorrhea and secondary amenorrhea. She was a mother of a child. She was on oral contraceptive pills while 3 years old, and she stopped contraception to try pregnancy for 4 years without success. She had no clinical features of hypopituitarism and was not taking any medication.
On physical examination, she had a blood pressure of 110/70 mmHg. She had bilateral galactorrhea.
PRL level was high, up to 200 ng/ml, and other pituitary and thyroid indices were normal, including testing for macroprolactinemia.
Pituitary MRI was normal [Figure 1]. An ectopic secretion of PRL was suspected, and thoraco-abdomino pelvic tomography was performed, with no abnormalities detected.
|Figure 1: Sagittal view of sellar magnetic resonance imaging depicting normal pituitary gland|
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Cabergoline was started at the dose 0.5 mg/week. Galactorrhea disappeared, the menstrual cycle had become regular, and PRL level decreased to 26 ng/ml.
| Discussion|| |
Human PRL is a single polypeptide hormone containing 198 amino acid residues identified in 1970. PRL synthesis and secretion by pituitary lactotroph cells are tonically suppressed by hypothalamic dopamine traversing the portal venous system to impinge on lactotroph D2 receptors.
Hyperprolactinemia is defined by a high level of serum PRL above the standard upper limit of normal range. It is the most common endocrine disorder of the hypothalamo–pituitary axis. The prevalence of hyperprolactinemia ranges from 0.4% to as high as 9% in an unselected normal adult population and 17% in women with reproductive disorders.
In nonpregnant and nonnursing women, the clinical picture mimics the puerperal period, characterized by irregular menses or amenorrhea, galactorrhea, infertility, and a decrease of libido. In men, hypogonadism, infertility, and libido impairment could be found. When a pituitary tumor is present, patients often have pressure symptoms in addition to endocrine dysfunction, such as headaches, visual field defects, or cranial nerve deficits.
A number of physiological states including pregnancy, breast-feeding, stress, exercise, and sleep can cause PRL elevation [Table 1]. The pathological causes of hyperprolactinemia include PRL-secreting pituitary adenoma (prolactinoma), intracranial tumors compressing the pituitary stalk or hypothalamus, PRL stimulative drugs, hypothyroidism, chest wall diseases, and hepatorenal disorders. Patients with renal insufficiency may have moderate hyperprolactinemia caused by impaired renal degradation of PRL and altered central PRL regulation.
However, 8.5%–40% of hyperprolactinemia is classified as “idiopathic hyperprolactinemia” because the causes are unknown. Some cases of microadenoma that cannot be detected by MRI are believed to fall into this category. Indeed, fewer than 10% of patients with idiopathic hyperprolactinemia ultimately are found to harbor a microadenoma. Anti-PRL autoantibodies were found from 16% of patients with idiopathic hyperprolactinemia, these patients generally lacked the clinical symptoms of hyperprolactinemia such as amenorrhea and galactorrhea, and spontaneous pregnancy was possible without treatment for hyperprolactinemia. De Bellis et al. found a high prevalence of antipituitary antibodies (APA) in 25.7% of patients with idiopathic hyperprolactinemia, whereas all patients with microprolactinomas and normal controls were negative for APA, and it must be suspected in patients with idiopathic hyperprolactinemia and personal or familial history of autoimmune disease. Macroprolactinemia in which most circulating PRL forms large protein complexes is a major cause of idiopathic hyperprolactinemia. The patients with macroprolactinemia are clinically characterized by the lack of hyperprolactinemia-related symptoms such as amenorrhea and galactorrhea.
Treatment is indicated in symptomatic patients with idiopathic hyperprolactinemia. The goals of treatment are to normalize PRL levels, to restore gonadal function, and to reduce the effects of chronic hyperprolactinemia. Dopaminergic agonist (DA) is the therapy of choice. At present, pharmacotherapy with cabergoline is accepted as the most appropriate medical treatment for hyperprolactinemia. The necessity of continuous treatment with DA should be reevaluated because serum PRL levels may remain normal after drug withdrawal. In a meta-analysis performed by Dekkers et al., 32% of patients with idiopathic hyperprolactinemia kept normal PRL levels after DA discontinuation. According to The Endocrine Society, clinical guidelines for diagnosis and treatment of hyperprolactinemia treatment with DA should be periodically discontinued, in patients who attained normoprolactinemia.
| Conclusion|| |
This case illustrates that idiopathic hyperprolactnemia must be diagnosed after all causes of hyperprolactnemia are ruled out, and pituitary imaging is revealed as negative. In symptomatic patients, treatment with DAs is indicated.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
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Conflicts of interest
There are no conflicts of interest.
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