Genetic findings in people with schwannomas who do not meet clinical diagnostic criteria for -related schwannomatosis.

Background: Most schwannomas are isolated tumours occurring in otherwise healthy people. However, bilateral vestibular schwannomas (BVS) or multiple non-vestibular schwannomas indicate an underlying genetic predisposition. This is most commonly -related schwannomatosis (SWN), but when BVS are absent, this can also indicate -related or -related SWN.

A serum potassium level above 10 mmol/l in a patient predisposed to hypokalemia.

Background: A 58-year-old man, previously diagnosed with Bartter's syndrome, presented with a short history of vomiting, diarrhea and weakness. He had severe hyperkalemia (serum potassium levels >10 mmol/l), which was successfully managed. Post hoc investigation suggested that the patient had Gitelman's rather than Bartter's syndrome.