Gitelman syndrome associated with chondrocalcinosis: description of two cases

Abstract

tuttavia disponibili dati certi riguardo alla prevalenza, che viene stimata tra 1.2 e 25 casi per milione (5, 6). La condrocalcinosi, come noto, è caratterizzata clinicamente da episodi di sinovite acuta o sinovite cronica, secondari al deposito di cristalli di pirofosfato diidrato di calcio a livello della cartilagine ialina e/o della fibrocartilagine (7). Diversi contributi in letteratura sottolineano l'associazione di SG e condrocalcinosi, considerata, quest'ultima, un tipico esempio di manifestazione secondaria ad ipomagnesemia (8)(9)(10)(11)(12)(13)(14). Descriviamo in seguito due casi di SG associati a condrocalcinosi, che illustrano due estremi dell'ampio ventaglio di presentazione di questa sindrome. CASO CLINICO 1Donna di 52 anni, all'età di 39 anni, per episodi ricorrenti di spasmo carpo-podalico, tetania, debolezza muscolare e parestesie prevalenti agli arti superiori, si ricovera presso la Clinica di Endocrinologia dell'Università Politecnica delle Marche, dove sulla base del quadro clinico, del rilievo di se-INTRODUZIONE L a sindrome di Gitelman (SG), descritta per la prima volta da Gitelman nel 1966 (1) è una rara tubulopatia ereditaria, trasmessa con tratto autosomico recessivo, caratterizzata da ipomagnesemia, ipopotassiemia, alcalosi metabolica, ipocalciuria ed iperaldosteronismo iperreninemico (2). Sul piano clinico può presentare un'ampia varietà di manifestazioni che procedono da un quadro sfumato di crampi, mialgie e/o debolezza muscolare, fino ad episodi di spasmo carpo-podalico, tetania e rabdomiolisi (3, 4). La mutazione responsabile della sindrome interessa il gene per la proteina NCCT (Na-Cl cotransporter), un cotrasportatore sodio-cloro presente nel tubulo contorto distale (5). La SG è considerata una malattia rara; non sono Reumatismo, 2010; 62(1)

Gitelman’s Syndrome Associated with Chondrocalcinosis: A Case Study from the Azores Islands (Portugal)

“…The GS patient described in this study has the S615L variation in homozygosity, while the other cases of GS with this variation were reported in compound heterozygotes [2]. In our study, seven individuals heterozygous for the S615L did not have either hypokalemia or hypomagnesemia, confirming that they were asymptomatic carriers of this variation.…”

“…The association of GS with chondrocalcinosis (CC) has been described in the literature as a typical example of hypomagnesemiainduced crystal deposition disease [2]. CC is characterized by deposition of crystals of calcium pyrophosphate dihydrate (CPPD) in articular hyaline and fibro-cartilage [2].…”

“…GS is characterized by hypomagnesemia, hypokalemia, metabolic alkalosis, hypocalciuria and hyperreninemic hyperaldosteronism. The clinical spectrum is wide and includes: cramps, myalgies, muscle weakness, tetania, and paralysis [2]. GS is mostly caused by loss of function mutations in the solute carrier family 12, member 3 (SLC12A3 gene) which consists of 26 exons and is located on the long arm of 16 th chromosome [1]; this gene encodes the thiazide-sensitive sodium-chloride cotransporter (NCCT), expressed in the distal convoluted tubule of the kidney [3].…”

“…CC is characterized by deposition of crystals of calcium pyrophosphate dihydrate (CPPD) in articular hyaline and fibro-cartilage [2]. Seventeen cases of GS associated with CC due to CCPD have been published in the literature, including 10 females and 7 males with a mean age of 51.4 ± 15.9 years [2,[5][6][7][8][9][10][11][12][13][14][15].…”

Gitelman syndrome disclosed by calcium pyrophosphate deposition disease: early diagnosis by ultrasonographic study

“…The clinical spectrum is wide and is characterized by chronic fatigue, cramps, muscle weakness and paresthesiae, nevertheless in our report none of these symptoms was present and knee arthritis was the only presenting symptom. Some authors have described an association between CPPD and Gitelman's syndrome (4)(5)(6). Probably, a key role is played by hypomagnesaemia because magnesium is a necessary cofactor for pyrophosphatases, a group of enzymes that increase the solubility of calcium pyrophosphate crystals.…”