title: Chondrocalcinosis secondary to hypomagnesemia in Gitelman's syndrome.
abstract: Chondrocalcinosis can be associated with hyperparathyroidism, hemochromatosis, hypophosphatasia, and hypomagnesemia. Gitelman syndrome (GS), an inherited disorder due to loss of function mutations of the gene encoding the distal convoluted tubule Na-Cl cotransporter (NCCT), is characterized by hypokalemia metabolic alkalosis, hypomagnesemia, and hypocalciuria. A 53-year-old man, with history of recurrent joint effusions and pains affecting knees and wrists, had transient episodes of muscle pain, weakness, cramping, and fatigue over a one-year period. Laboratory tests showed hypokalemia, metabolic alkalosis, hypocalciuria, and hypomagnesemia related to genetically proven GS. Radiographs of affected joints revealed calcium pyrophosphate dihydrate deposition. This observation points out the necessity to look for Mg depletion (and especially GS) in the biological investigation of chondrocalcinosis. Additionally, the association between GS (NCCT inactivation) and high bone mineral density provides a new insight into the possible role of thiazides in osteoporosis management.
authors.affiliation: Rheumatology Department, René Descartes University, France. korng.ea@free.fr
authors.forename: Hang-Korng
authors.initials: HK
authors.lastname: Ea
authors.forename: Anne
authors.initials: A
authors.lastname: Blanchard
authors.forename: Maxime
authors.initials: M
authors.lastname: Dougados
authors.forename: Christian
authors.initials: C
authors.lastname: Roux
mesh_terms: D001477:Bartter Syndrome / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics*; D001774:Blood Chemical Analysis; D015519:Bone Density; D002805:Chondrocalcinosis / Q000150:complications / Q000188:drug therapy / Q000209:etiology*; D004359:Drug Therapy, Combination; D005500:Follow-Up Studies; D006801:Humans; D008274:Magnesium / Q000097:blood / Q000378:metabolism* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011188:Potassium / Q000627:therapeutic use; D018570:Risk Assessment; D012720:Severity of Illness Index; D013148:Spironolactone / Q000627:therapeutic use; D016896:Treatment Outcome
chemical_list: D013148:Spironolactone; D008274:Magnesium; D011188:Potassium