Macroprolactinemia in childhood and adolescence: A cause of hyperprolactinemia
Turkish Journal of Pediatrics, cilt.48, sa.2, ss.143-147, 2006 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 48 Sayı: 2
- Basım Tarihi: 2006
- Doi Numarası: 10.24953/turkjped.2006.2616
- Dergi Adı: Turkish Journal of Pediatrics
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.143-147
- Anahtar Kelimeler: Adolescent, Childhood, Hyperprolactinemia, Macroprolactinemia, Prolactin
- Trakya Üniversitesi Adresli: Evet
Özet
Human prolactin consists of multiple forms of different sizes including three major prolactin (PRL) species, termed as little, big, and big-big PRL. If serum contains big-big PRL, it is termed macroprolactinemia; no symptoms of hyperprolactinemia develop due to low biological activity of big-big PRL. There are still few data regarding macroprolactinemia in children and adolescents. In this paper we describe six patients with macroprolactinemia, one of whom was asymptomatic and the other five either had headache, menstrual disturbance, short stature, increased hair growth or early puberty, compatible with high PRL levels. Two of the cases had microadenoma. Initial mean±SD PRL levels of the patients were 75.2±22.8 ng/ml (range: 42.3-105.2 ng/ml). Macroprolactin analysis revealed big-big PRL levels of the patients ranging between 21.6-98.6 ng/ml. It was noteworthy that bromocriptine (BRC) therapy started in three patients caused an abrupt decrease in PRL levels. It may be concluded that macroprolactinemia should be taken into account in the differential diagnosis of hyperprolactinemia in childhood and adolescence, whether or not they have relevant clinical symptoms. Indications:3 patients with hyperprolactinemia due to macroprolactinemia. Concomitant disease: macroadenoma (2). Patients:6 patients, 3 male and 3 female, aged 9.1 to 14.3 years were studied. 3 patients received Parlodel therapy. Patient 1: 11.5-year-old male patient. Patient 2: 9.3-year-old male patient. Patient 3: 14.3-year-old female patient; the patient dropped out due to side effects. TypeofStudy:This study described the outcome of Parlodel therapy in patients with hyperprolactinemia due to macroprolactinemia. Case series. DosageDuration:5 mg daily. Duration: 24 months (patient 1) and 2 years (patient 2). Results:At 3 months of Parlodel therapy, serum PRL levels of patient 1 decreased, thereby tapering the Parlodel dose (equivalent to serum Parlodel level of 0.8 ng/ml). Serum PRL level at 6 months was 7.5 ng/ml. Following the disappearance of the microadenoma on repeat MRI, Parlodel therapy was discontinued, which resulted in an increased PRL levels (124 ng/ml). Retreatment with Parlodel resulted in an abrupt decrease in PRL levels. After 18 months, Parlodel therapy was discontinued. Serum PRL increased again with evidence of macroprolactinemia. Following initiation of Parlodel therapy, a sharp decrease in PRL levels was observed in patient 2. After 2 years, Parlodel therapy was discontinued because of the absence of clinical or radiological findings except for mild headaches. A subsequent increase in PRL level, while without Parlodel therapy, was determined to be due to macroprolactinemia. Patient 3 still experienced irregular menstruation even after the initiation of Parlodel therapy, which was eventually discontinued because of the occurrence of severe gastrointestinal symptoms. A subsequent increase in PRL level was found to be caused by macroprolactinemia. AdverseEffects:1 patient developed severe gastrointestinal symptoms, leading to withdrawal of Parlodel therapy. AuthorsConclusions:In conclusion, we suggest that all children and adolescents with hyperprolactinemia, especially when asymptomatic or associated with non-specific clinical features or even associated with relevant symptoms of increased PRL levels, should be evaluated for macroprolactinemia. Further, imaging studies should be performed when indicated by clinically relevant features. Once macroprolactinemia is diagnosed, the evidence to date does not favor medical therapy with BRC [bromocriptine]. However, the underlying mechanism of macroprolactinemia is still not very clear and patients should be followed for clinical symptoms. FreeText:Patient 1 presented with prolactin (PRL) level of 105.2 ng/ml. Magnetic resonance imaging (MRI) revealed a microadenoma. Patient 2 presented with PRL level of 79.2 ng/ml. Patient 3 presented with irregular menstruation and high PLR levels. MRI revealed a microadenoma.