Bartter's and Gitelman's syndrome.

Purpose Of Review: The clinical presentations of Bartter's syndrome and Gitelman's syndrome will be reviewed including two most recently described hypokalemic salt-losing tubulopathies. By taking the quite heterogeneous presentations and the apparently different pathophysiologies as the basis, the applicability of the physiologic classification has been tested.

Recent Findings: According to the physiologic approach, salt-losing tubulopathies can be divided into two major groups (with completely different tubular defects): first, disorders of the thick ascending limb of Henle's loop (loop disorders); second, disorders of the distal convolute tubule (DCT disorders).

Polyhydramnios, Transient Antenatal Bartter's Syndrome, and MAGED2 Mutations.

Background: Three pregnancies with male offspring in one family were complicated by severe polyhydramnios and prematurity. One fetus died; the other two had transient massive salt-wasting and polyuria reminiscent of antenatal Bartter's syndrome.

Methods: To uncover the molecular cause of this possibly X-linked disease, we performed whole-exome sequencing of DNA from two members of the index family and targeted gene analysis of other members of this family and of six additional families with affected male fetuses.

Pathophysiology and clinical presentations of salt-losing tubulopathies.

At least three renal tubular segments are involved in the pathophysiology of salt-losing tubulopathies (SLTs). Whether the pathogenesis starts either in the thick ascending limb of the loop of Henle (TAL) or in the distal convoluted tubule (DCT), it is the function of the downstream-localized aldosterone sensitive distal tubule (ASDT) to contribute to the adaptation process. In isolated TAL defects (loop disorders) ASDT adaptation is supported by upregulation of DCT, whereas in DCT disorders the ASDT is complemented by upregulation of TAL function.

Basics and dynamics of neonatal and pediatric pharmacology.

Understanding the role of ontogeny in the disposition and actions of medicines is the most fundamental prerequisite for safe and effective pharmacotherapeutics in the pediatric population. The maturational process represents a continuum of growth, differentiation, and development, which extends from the very small preterm newborn infant through childhood, adolescence, and to young adulthood. Developmental changes in physiology and, consequently, in pharmacology influence the efficacy, toxicity, and dosing regimen of medicines.