RT Journal Article
SR Electronic
T1 Gitelman or Bartter type 3 syndrome? A case of distal convoluted tubulopathy caused by CLCNKB gene mutation
JF BMJ Case Reports
FD BMJ Publishing Group Ltd
SP bcr2012007929
DO 10.1136/bcr-2012-007929
VO 2013
A1 António José Cruz
A1 Alexandra Castro
YR 2013
UL http://casereports.bmj.com/content/2013/bcr-2012-007929.abstract
AB A 32-year-old woman with no significant medical history was sent to our consultation due to hypokalaemia (<3.0 mmol/l). Her main complaints were longstanding polyuria and nocturia. Physical examination was normal. Basic investigations showed normal renal function, low serum potassium (2.7 mmol/l) and magnesium (0.79 mmol/l), metabolic alkalosis (pH 7.54; bicarbonate 32.5 mmol/l), elevated urinary potassium (185 mmol/24 h) and normal urinary calcium (246 mg/24 h). Thiazide test revealed blunted response. Chronic vomiting and the abuse of diuretics were excluded. Genetic tests for SLC12A3 gene mutation described in Gitelman syndrome (GS) came negative. CLCNKB gene mutation analysis present in both GS and Bartter (BS) type 3 syndromes was positive. The patient is now being treated with potassium and magnesium oral supplements, ramipril and spironolactone with stable near-normal potassium and magnesium levels. This article presents the case of a patient with hypokalaemia caused by CLCNKB gene mutation hard to categorise as GS or BS type 3.