Current recommendations for evaluation of adrenal incidentaloma are likely to result in significant costs, both financial and emotional, due to high false-positive rates. The dose of radiation involved in currently recommended CT scan follow-up confers a risk of fatal cancer that is similar to the risk of the adrenal becoming malignant. This argues for a review of current guidelines.

Low-dose corticotropin test was superior to standard-dose test for diagnosing chronic HPAI, although it has technical limitations.

SUMMARY. For a period of 12 months all samples submitted for serum prolactin (PRL) assay and with PRL> 700 mUlL were examined by gel filtration chromatography. In 17 (25%) of 69 samples we found macroprolactin. The Delfia and Immuno I immunoassay systems gave similar PRL results with samples containing macroprolactin whereas the ACS 180 system gave lower results. With the De1fia and Immuno 1 systems samples containing substantial quantities of macroprolactin showed low recovery of PRL after precipitation with polyethylene glycol 6000 (PEG 6000) and this technique can be used as a screening test for macroprolactinaemia.We conclude that macroprolactinaemia is a common phenomenon and, in assays which detect this species, is a common cause of hyperprolactinaemia. Macroprolactinaemia may contribute to the difficulty in establishing an upper limit of the reference range for serum PRL. In our experience, patients with macroprolactinaemia do not exhibit features of the hyperprolactinaemia syndrome and it is important to recognize macroprolactin as the cause of hyperprolactinaemia to avoid unnecessary investigation and treatment.

Parenteral iron suppresses renal tubular phosphate reabsorption and 1alpha-hydroxylation of vitamin D resulting in hypophosphatemia. Our data suggest that this is mediated by an increase in FGF23.

Iron-induced renal phosphate wasting, hypophosphataemia and osteomalacia have previously been reported in a small number of Japanese patients receiving parenteral iron sucrose. We report the case history of a European male who, as a result of regular intravenous iron polymaltose, developed prolonged hypophosphataemia complicated by widespread insufficiency fractures. The pathogenesis of this complication remains unknown however our novel finding of a marked elevation in fibroblast growth factor 23 (FGF23), which normalized after ceasing parenteral iron, suggests an important and previously unreported effect of iron on FGF23 homeostasis.