Hypersecretion of prolactin by lactotroph cells of the anterior pituitary may lead to hyperprolactinemia in physiological, pathological and idiopathic conditions. Most patients with idiopathic hyperprolactinemia may have radiologically undetected microprolactinomas, but some may present other causes of hyperprolactinemia described as macroprolactinemia. This condition corresponds to the predomi...

Serum human prolactin (PRL) is heterogeneous in molecular size, with the 23-kDa monomer being the predominant form in healthy subjects and patients with prolactinomas. From the point of view of molecular size, other circulating forms include the 50-kDa dimer (big-PRL) and the 150to 170-kDa form (big-big-PRL, or macroprolactin) (1). Recent publications have associated asymptomatic hyperprolactin...

within 21 days. The likelihood ratio for a negative result [(1 sensitivity)/specificity] was 0.59 for birth within 7 days, 0.68 for birth within 14 days, and 0.53 for birth within 21 days. The data in Table 1 are similar to those obtained in previous studies using the ELISA-based assay. Joffe et al. (1 ) reported a NPV of 99.6% and a PPV of 9.1% for 243 patients who delivered within 7 days with...

In April 2007, a 21-year-old woman presented with secondary amenorrhoea for 5 years. Her past medical history included bilateral valgus heels with difficulty in walking as a toddler, fractured nose and epistaxis with nasal septum deviation (seen in ENT clinic in 1998). She had a family history of migraine and was referred to the neurology clinic for throbbing headaches in the right frontal regi...

Interference by human anti-animal immunoglobulins, commonly referred to as heterophile antibodies, in immunologic assays is known to be an important consideration for medical testing laboratories (1–3). Although automated immunometric assays are formulated to reduce these effects, it is unlikely that complete elimination occurs (2 ), and artifactual results attributable to heterophile antibodie...

Despite the advent modern immunoassays, particularly with regards to TSH measurements, clinicians still encounter seemingly inexplicable results of thyroid function tests, for instance raised concentrations of free hormones (free T4 and/or free T3) in the setting of high, or at least not suppressed TSH concentrations. Though cases of TSH-oma or thyroid hormone resistance do exist, they are in f...