This study for check details recurrent hyponatremic episodes following the first admission with severe hyponatremia (<125 mEq/L) on thiazide aimed to investigate whether other coexistent factors than thiazide are responsible.
Methods: In the retrospective chart review over 5 yrs, out of 1,625 pts admitted with severe hyponatremia on hydrochlorothiazide (HCTZ), 24 pts (M : F, 7:17; age 71 ± 11 yrs, mean ± SD) were re-admitted for the recurrent hyponatremia (up to 4 times). Results: Among the 1st (n, 24), the 2nd (n, 24), the 3rd (n, 6), and the 4th admission (n, 2), serum sodium levels on admission were not significantly different (122 ± 3.8 vs 120 ± 6.7 vs 119 ± 5.4 vs 115 ± 19.1 mEq/L, p = ns). Successful managements of the 1st admission (n, 24) included discontinuing HCTZ with intravenous salt (n, 17), withdrawing HCTZ only (n, 1), and inadvertent continuation of HCTZ with intravenous salt (n, 6). As the causes of hyponatremia on
the 2nd admission (n, 24), 14 10 pts (42%) with no further exposure to HCTZ revealed volume depletion (n, 6), SIADH (n, 3), and adrenal insufficiency (n, 1), respectively. Four pts on the second admission died of malignancy, not from hyponatremia. Moreover, 4 pts on HCTZ in the 1st (17%) and the 2nd admission (17%), and also 2 pts on the 3rd admission (33%) were simultaneously taking neuropsychiatric medications and other diuretics with either furosemide or spironolactone. The latter 2 pts of the 3rd admission experienced the 4th admission of recurrent hyponatremia. Conclusion: In summary, hyponatremia Orotidine 5′-phosphate decarboxylase on thiazide Selleckchem Roxadustat does not mean necessarily thiazide alone as the sole cause of its frequent occurrence. Therefore, thiazide-associated hyponatremia warrants prudent exploration for other coexistent causes of hypontremia. SOHARA
EISEI, SUSA KOICHIRO, RAI TATEMITSU, ZENIYA MOKO, MORI YUTARO, SASAKI SEI, UCHIDA SHINICHI Department of Nephrology, Tokyo Medical and Dental University Introduction: Pseudohypoaldosteronism type II (PHAII) is a hereditary disease characterized by salt-sensitive hypertension, hyperkalemia and metabolic acidosis, and genes encoding the WNK1 and WNK4 kinases were known to be responsible. Recently, two genes (KLHL3 and Cullin3) were newly identified as responsible for PHAII. KLHL was identified as substrate adaptors in the Cullin3-based ubiquitin E3 ligase. We have reported that WNK4 is the substrate of KLHL3-Cullin3 E3 ligase-mediated ubiquitination. However, WNK1 and NCC were also reported to be a substrate of KLHL3-Cullin3 E3 ligase by other groups. Therefore, it remains unclear which molecule is true substrate(s) of KLHL3-Cullin3 E3 ligase, in other words, what is the true pathogenesis of PHAII caused by KLHL3 mutation. Methods: To investigate the pathogenesis of PHAII by KLHL3 mutation, we generated and analyzed KLHL3R528H/+ knock-in mice.