Un modelo de estudio de la función tubular renal que no depende de la colección de orina de 24 horas / A model of study of renal tubular function that does not depend on the 24-hour urine collection

Introducción: El ensayo de muestras matutinas de orina pudiera mejorar el estudio de la función tubular en niños y adolescentes. Objetivo: Describir las tubulopatías diagnosticadas en niños y adolescentes después del ensayo de muestras matutinas de orina. Métodos: Se completó un estudio retrospectivo y analítico en el Laboratorio de Estudio de la Función Renal, Servicio de Laboratorio Clínico, Hospital Pediátrico Docente "Juan Manuel Márquez", con 70 informes de la función tubular hechos en muestras matutinas de orina de 56 probandos (varones: 50,0 por ciento; edad promedio: 4,3 ± 5,5 años; edades < 12 meses: 41,1 por ciento) atendidos entre 2015-2019 (ambos inclusive) que contenían los valores del filtrado glomerular, la excreción urinaria absoluta y fraccional de las sustancias de interés, la brecha aniónica, la presión parcial de los gases, y la acidez titulable, el pH, la densidad y la osmolaridad de los fluidos pertinentes. Los resultados obtenidos se integraron dentro de las construcciones de caso de varias tubulopatías. Resultados: La función tubular estaba conservada en el 41,1 por ciento de los probandos. La inmadurez tubular explicó los hallazgos en otros dos niños. La hipercalciuria idiopática (16,0 por ciento), la diabetes insípida de causa nefrogénica (8,9 por ciento) y la insuficiencia renal aguda (5,3 por ciento) fueron los hallazgos más frecuentes. En 14 de los probandos se diagnosticaron 10 tubulopatías que recorrieron el raquitismo carencial, la hipofosfatasia, la enfermedad de Leigh, el síndrome de Bartter, la enfermedad de Dent y la acidosis tubular I, II y IV. Conclusiones: El estudio tubular en muestras matutinas de orina permite el diagnóstico de importantes tubulopatías en las edades pediátricas(AU)

Introduction: The morning urine sample assay may improve the study of tubular function in children and adolescents. Objective: Describe the tubulopathies diagnosed in children and adolescents after the trial of morning urine samples. Methods: A retrospective and analytical study was completed at the Renal Function´s Study Laboratory, in the Clinical Laboratory Service at "Juan Manuel Marquez" Teaching Pediatric Hospital, with 70 reports of tubular function made in morning urine samples of 56 testees (males: 50.0 percent; average age: 4.3 ± to 5.5 years; ages< 12 months: 41.1 percent) attended from 2015 to 2019 (both inclusive) containing glomerular filtration values, absolute and fractional urinary excretion of substances of interest, anionic gap, partial gas pressure, and titrable acidity, pH, density and osmolarity of relevant fluids. The results obtained were integrated into the case constructions of various tubulopathies. Results: Tubular function was preserved in 41.1 percent of the testees. Tubular immaturity explained the findings in two other children. Idiopathic hypercalciuria (16.0 percent), nephrogenic diabetes insipidus (8.9 percent) and acute renal failure (5.3 percent) were the most frequent findings. In 14 of the testees, 10 tubulopathies were diagnosed were through deficiency rickets, hypophosphatasia, Leigh's disease, Bartter syndrome, Dent disease and tubular acidosis I, II and IV.. Conclusions: The tubular study with morning urine samples allows the diagnosis of important tubulopathies in the pediatric ages(AU)

Role of prostaglandin E2 in the modulation of renal water transport / 生理学报

Prostaglandin E2 (PGE2), a bioactive lipid mediator, is one of the most important locally acting factors involved in a variety of physiological and pathophysiological processes. PGE2 binds with four EP receptors (EP1-4) to activate G protein-coupled receptor signaling responses. Recent functional and molecular studies have revealed that PGE2 plays an essential role in regulation of renal fluid transport via a variety of mechanisms. The water balance mainly depends on the regulation of aquaporin-2 (AQP2) by arginine vasopressin (AVP) in renal collecting duct principal cells. In recent years, increasing evidence suggests that PGE2 plays an important role in renal water reabsorption in the collecting ducts. In this paper, we reviewed the role of PGE2 and its receptors in the regulation of water reabsorption in the kidney, which may provide a new therapeutic strategy for many diseases especially nephrogenic diabetes insipidus.

Clinical characteristics and molecular genetics of seven neonates with congenital nephrogenic diabetes insipidus / 中华医学遗传学杂志

OBJECTIVE@#To explore the clinical characteristics, genetic basis and clinical treatment of seven neonates with congenital nephrogenic diabetes insipidus (NDI).@*METHODS@#Clinical data of the patients were collected. High-throughput sequencing was carried out to detect potential variants. Sanger sequencing was used to verify the results.@*RESULTS@#The patients were all males, with the age of onset being 10 to 21 days. All patients were admitted to the hospital for intermittent fever as the first symptom during the neonatal period. Additional symptoms had included polydipsia and polyuria. After the treatment, 5 patients had recovered, the remainders still had NDI symptoms and developmental retardation. Five children were found to harbor pathogenic variants of the AVPR2/AQP2 gene, which included one in-frame mutation of c.645_646insGCACCTACCCTGGGTATCGCC, two missense mutations of c.541C>T and c.419C>A, and two hemizygous deletions of the AVPR2/AQP2 gene. Among these, two were unreported previously. Cases 6 and 7 were a pair of twins. Both had carried homozygous missense variants of c.538G>A of the AVPR2/AQP2 gene, which was known to be pathogenic.@*CONCLUSION@#AVPR2/AQP2 is the main pathogenic gene for congenital NDI, for which two novel pathogenic variants have been discovered in this study. Above results have provided a basis for clinical diagnosis and genetic counseling for the affected pedigrees.

Lithium, an old friend and a forgotten enemy

SUMMARY INTRODUCTION: Nephrogenic diabetes insipidus (DI) is a polyuric and polydipsic syndrome and can have multiple causing factors. CASE DESCRIPTION: A 69-year-old woman with bipolar disorder medicated with lithium 400mg for 12 years on a daily basis. The patient was admitted, after psychiatric decompensation, with hypernatremia unresponsive to hypotonic iv fluids. The diagnosis of DI was made with high plasmatic osmolality measurement, low urine osmolality, and high levels of antidiuretic hormone. Full clinical recovery was possible with lithium suspension, hydration, and chlorthalidone. DISCUSSION: Although frequently used in the past, Lithium (Li) is nowadays rarely used in clinical practice for prolonged treatments because of its potentially devastating side effects. Clinicians must be aware of those side effects in order to prevent organ damage, mainly in patients with severe bipolar disease and precarious response to alternative treatments.

RESUMO INTRODUÇÃO: O diabetes insípido nefrogênico faz parte das síndromes poliúricas polidipsicas e pode ter múltiplos fatores causais. CASO CLÍNICO: Mulher de 69 anos, com doença bipolar medicada com lítio 400 mg por dia durante 12 anos. A doente foi internada, após descompensação da doença bipolar, por hipernatremia não responsiva a fluidoterapia hipotônica endovenosa. O diagnóstico de DI foi realizado com base na elevação da osmolaridade plasmática, baixa osmolaridade urinária e níveis elevados de hormona antidiurética. Verificou-se recuperação clínica completa com suspensão do lítio, hidratação e clorotalidona. DISCUSSÃO: Apesar do seu uso frequente no passado, o lítio (Li) é hoje em dia raramente utilizado na prática clínica por períodos prolongados pelos seus efeitos potencialmente devastadores. Os médicos devem ter em conta os potenciais efeitos secundários de forma a prevenir lesão de órgão em doentes com doença bipolar de difícil controle com outra terapêutica.

Analysis of AVPR2 variant in a neonate with congenital nephrogenic diabetes insipidus / 中华医学遗传学杂志

OBJECTIVE@#To detect potential variant in a male neonate affected with congenital nephrogenic diabetes insipidus (CNDI).@*METHODS@#Clinical data of the patient was collected. Genomic DNA was extracted from peripheral blood samples from the child and his parents. The whole coding regions of the arginine vasopressin V2 receptor (AVPR2) gene were amplified by PCR and subjected to Sanger sequencing.@*RESULTS@#The patient presented recurrent fever and polyuria after birth. Multiple blood gas analyses indicated hypernatremia. Ultrasound showed bilateral hydronephrosis and hydroureter. The patient was partially responsive to hydrochlorothiazide. DNA analysis identified a hemizygous frameshift variant c.890-899delACCCGGAGGC in exon 2 of the AVPR2 gene in the proband. His mother was heterozygous for the same variant.@*CONCLUSION@#The c.890-899delACCCGGAGGC variant of the AVPR2 gene probably underlies the CNDI in the child. Above discovery has enriched to spectrum of CNDI associated variants.

Alteraciones endocrinas vinculadas a la prescripción médica de carbonato de litio. Una revisión narrativa / Endocrinological Disorders Related to the Medical Use of Lithium. A Narrative Review

RESUMEN La prescripción de carbonato de litio es común en la actividad psiquiátrica cotidiana. El objetivo es identificar las alteraciones endocrinas secundarias y sus bases fisiopatológicas. La revisión de la literatura se realizó en Psycinfo, EMBASE, PubMed y Scopus. Se efectuó una búsqueda computarizada de información utilizando la estrategia PICO. Las alteraciones más comunes están en riñones, tiroides, paratiroides, páncreas y vías neuroendocrinas. Los mecanismos fisiopatológicos subyacentes son diversos, y destacan la inhibición de la adenilato ciclasa tiroidea sensible a tirotropina como causa de hipotiroidismo, la expresión reducida de acuaporina 2 como causa de diabetes insípida nefrogénica, la pérdida del equilibrio iónico del calcio y la presencia de hiperparatiroidismo e hipercalcemia. En el eje hipotálamo-hipófiso-adrenal, se documenta una disminución en la producción de catecolaminas. Finalmente, se documenta la desregulación en el control de la glucemia al aumentar la resistencia a la insulina. Es necesario conocer estas eventualidades e identificarlas tempranamente a través de evaluaciones periódicas. Se propone un esquema de evaluación integral, sin que implique un algoritmo de tratamiento.

ABSTRACT The prescribing of Lithium is common in psychiatric clinical practice. The aim of this study was to identify the most common endocrine side effects associated with this drug and to clarify the pathophysiological basis. A systematic review was conducted in Psycinfo, Embase, PubMed, and Scopus. A computerised search for information was performed using a PICO (patient, intervention, comparative, outcomes) strategy. The main neuroendocrine alterations were reported in kidneys, thyroid and parathyroid glands, pancreas, and the communication pathways between the pituitary and adrenal glands. The pathophysiological mechanisms are diverse, and include the inhibition of the thyroid adenylate cyclase sensitive to the thyroid stimulant hormone (TSH) sensitive adenylate cyclase, which causes hypothyroidism. It also reduces the expression of aquaporin type 2, which is associated with nephrogenic diabetes insipidus, and the loss of the ionic balance of calcium that induces hyperparathyroidism and hypercalcaemia. Other considerations are related to alterations in the hypothalamic-pituitary-adrenal axis and a decrease in the production of catecholamines. Finally, another side-effect is the glycaemic dysregulation caused by the insulin resistance. Periodical clinical and para-clinical evaluations are necessary. The author proposes an evaluation scheme.

Genetic diagnosis for a pedigree affected with hereditary nephrogenic diabetes insipidus / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for pedigree affected with hereditary nephrogenic diabetes insipidus (HNDI).@*METHODS@#Next generation sequencing (NGS) with an osteology system gene panel was carried out for the proband. Suspected mutation was validated by Sanger sequencing of two relatives with similar symptoms and two unaffected relatives from the pedigree.@*RESULTS@#The proband was found to carry a c.856C>T mutation of the AVPR2 gene. The same mutation was detected in the two relatives with similar symptoms and one unaffected healthy relative.@*CONCLUSION@#The HNDI in this pedigree may be attributed to the c.856C>T mutation of the AVPR2 gene.

New insights into the transcriptional regulation of aquaporin-2 and the treatment of X-linked hereditary nephrogenic diabetes insipidus

The kidney collecting duct (CD) is a tubular segment of the kidney where the osmolality and final flow rate of urine are established, enabling urine concentration and body water homeostasis. Water reabsorption in the CD depends on the action of arginine vasopressin (AVP) and a transepithelial osmotic gradient between the luminal fluid and surrounding interstitium. AVP induces transcellular water reabsorption across CD principal cells through associated signaling pathways after binding to arginine vasopressin receptor 2 (AVPR2). This signaling cascade regulates the water channel protein aquaporin-2 (AQP2). AQP2 is exclusively localized in kidney connecting tubules and CDs. Specifically, AVP stimulates the intracellular translocation of AQP2-containing vesicles to the apical plasma membrane, increasing the osmotic water permeability of CD cells. Moreover, AVP induces transcription of the Aqp2 gene, increasing AQP2 protein abundance. This review provides new insights into the transcriptional regulation of the Aqp2 gene in the kidney CD with an overview of AVP and AQP2. It summarizes current therapeutic approaches for X-linked nephrogenic diabetes insipidus caused by AVPR2 gene mutations.

Asociación diabetes tipo 2 y tuberculosis pulmonar en pacientes de imsalud en la zona atalaya de cúcuta entre 2013 y 2015 / Association of type 2 diabetes mellitus and tuberculosis in imsalud patients in the atalaya zone of cucuta 2013-2015 / Associação entre diabetes mellitus tipo 2 e tuberculose em pacientes de imsalud na zona atalaya de cúcuta 2013-2015

Resumen Objetivo: Establecer la asociación entre diabetes mellitus tipo 2 (DM2) y tuberculosis pulmonar (TBp) en los pacientes que asisten al servicio de consulta externa en las IPS de Imsalud de la Zona Atalaya de Cúcuta, Norte de Santander. Material y métodos: Se realizó un estudio observacional, analítico, de tipo casos y controles, en que se seleccionaron a todos los pacientes que asistieron a las IPS de Imsalud de la Zona Atalaya de enero de 2013 a diciembre de 2015 (28 015 pacientes). Se revisaron las historias clínicas de los pacientes con diagnóstico de TB (100) y se obtuvo el consolidado de pacientes diabéticos (847) a partir de la base de datos de Imsalud. Resultados: De una población total de 28 015 pacientes, 100 (0,4%) y 847 (3%) tenían diagnóstico de TBp y DM2, respectivamente. De los 100 pacientes con tuberculosis, 17 (0,1%) tenían a la vez diagnóstico de DM2. La asociación estadística (chi cuadrado) para las variables DM2 y TBp reportó un resultado de 66,8 para una p:<0,05 (IC: 5,1-8,3). Conclusiones: La literatura plantea que existe mayor susceptibilidad en las personas con DM2 de contraer TBp y que esta puede ser explicada por defectos en la inmunidad celular, causados por los periodos de hiperglicemia, además de la alteración de las funciones de los leucocitos polimorfonucleares. En este estudio, se estableció una asociación significativa del binomio DM2-TBp, que reporta que existe un riesgo (OR) 6,7 veces mayor de desarrollar TBp en pacientes con antecedente de DM2 que en aquellos que no presentan esta comorbilidad.

Abstract Objective: To establish the association between type 2 diabetes mellitus (DM2) and pulmonary tuberculosis (TBp) in patients attending the outpatient service in the Health Care Provider (IPS from "Institución Prestadora de Salud" in Spanish) of Imsalud of the Atalaya Zone in Cucuta, Norte de Santander. Material and methods: An observational, analytical, case-control study was conducted, in which all the patients who attended the IPS of Imsalud in the Atalaya Zone from January 2013 to December 2015 (28,015 patients) were selected. The medical records of patients with a diagnosis of TB (100) were reviewed and the consolidation of diabetic patients (847) was obtained from the Imsalud database. Results: Out of a total population of 28,015 patients, 100 (0.4%) and 847 (3%) had a diagnosis of TBp and DM2, respectively. Out of the 100 patients with tuberculosis, 17 (0.1%) also had a diagnosis of DM2. The statistical association (chi square) for the variables DM2 and TBp reported a result of 66.8 for a p: <0.05 (CI: 5.1-8.3). Conclusions: The literature suggests that there is greater susceptibility in people with DM2 to contract TBp and that this can be explained by defects in cellular immunity, caused by periods of hyperglycemia, in addition to the alteration of the functions of polymorphonuclear leukocytes. In this study, a significant association of the DM2-TBp binomial was established, which states that there is a 6.7 times greater risk (OR) of developing TBp in patients with a history of DM2 than in those who do not have this comorbidity.

Resumo Objetivo: Estabelecer a associação entre diabetes mellitus tipo 2 (DM2) e tuberculose pulmonar (TBp) nos pacientes que vão ao serviço de consulta externa nas IPS de Imsalud da Zona Atalaya de Cúcuta, Norte de Santander. Material e métodos: Realizou-se um estudo observacional, analítico, de tipo casos e controles, em que se selecionaram todos os pacientes que foram às IPS de Imsalud da Zona Atalaya de janeiro de 2013 a dezembro de 2015 (28 015 pacientes). Revisaram-se as histórias clínicas dos pacientes com diagnóstico de TB (100) e obteve-se o consolidado de pacientes diabéticos (847) a partir do banco de dados de Imsalud. Resultados: De uma população total de 28 015 pacientes, 100 (0,4%) e 847 (3%) tinham diagnóstico de TBp e DM2, respectivamente. Dos 100 pacientes com tuberculoses, 17 (0,1%) tinham ao mesmo tempo diagnóstico de DM2. A associação estatística (qui-quadrado) para as variáveis DM2 e TBp apresentou um resultado de 66,8 para um p:<0,05 (IC: 5,1-8,3). Conclusões: A literatura propõe que exista maior suscetibilidade nas pessoas com DM2 de contrair TBp e que esta pode ser explicada por defeitos na imunidade celular, causados pelos períodos de hiperglicemia, além da alteração das funções dos leucócitos polimorfonucleares. Neste estudo, estabeleceu-se uma associação significativa do binómio DM2-TBp, que mostra que existe um risco (OR) 6,7 vezes maior de desenvolver TBp em pacientes com antecedente de DM2 que nos que não apresentam essa comorbidade.

Diabetes Insípida inducida por el embarazo o gestacional: a propósito de un caso / Pregnancy or Gestational Diabetes Insipidus: a purpose of a case

RESUMEN Antecedentes: La incidencia de la diabetes insípida gestacional es aproximadamente 1/30.000 gestaciones. Objetivo: A propósito de un caso de diabetes insípida gestacional ocurrida en nuestra unidad, se decide comunicar y revisar la literatura referente a opciones de manejo y tratamiento del mismo. Caso clínico: Mujer de 38 años, primigesta de 32 semanas con clínica de poliuria y polidipsia con una ingesta hídrica diaria de hasta 7 litros. Tras realizar las pertinentes exploraciones complementarias y descartar otras patologías más frecuentes, se establece el diagnóstico de diabetes insípida gestacional. Conclusiones: La diabetes insípida gestacional es una entidad muy poco frecuente que puede desencadenar en un estado de deshidratación intensa con hipernatremia y su consecuente afectación neurológica. Es importante el diagnóstico precoz para evitar las complicaciones tanto a nivel materno como fetal, así como realizar un manejo multidisciplinar de esta patología.

ABSTRACT Background: The incidence of diabetes insipidus during pregnancy is approximately 1 in 30,000 pregnancies. Objective: We herein report a case of a patient with gestational diabetes insipidus occurring in our unit. We decided to communicate the case and review the literature regarding management and treatment options. Case report: A 38-year-old woman at 32 week of pregnancy with polyuria, polydipsia, and daily water intake of up to 7 liters. After performing the complementary tests and ruling out other more frequent conditions, the diagnosis of gestational diabetes insipidus was established. Conclusion: Gestational diabetes insipidus is a very rare entity that can cause a state of intense dehydration with hypernatremia and its consequent neurological impairment. Early detection is important in order to avoid complications of both mother and fetus, as well as to carry out a multidisciplinary management of this condition.

Altered Nitric Oxide System in Cardiovascular and Renal Diseases / 전남의대학술지

Nitric oxide (NO) is synthesized by a family of NO synthases (NOS), including neuronal, inducible, and endothelial NOS (n/i/eNOS). NO-mediated effects can be beneficial or harmful depending on the specific risk factors affecting the disease. In hypertension, the vascular relaxation response to acetylcholine is blunted, and that to direct NO donors is maintained. A reduction in the activity of eNOS is mainly responsible for the elevation of blood pressure, and an abnormal expression of iNOS is likely to be related to the progression of vascular dysfunction. While eNOS/nNOS-derived NO is protective against the development of atherosclerosis, iNOS-derived NO may be proatherogenic. eNOS-derived NO may prevent the progression of myocardial infarction. Myocardial ischemia/reperfusion injury is significantly enhanced in eNOS-deficient animals. An important component of heart failure is the loss of coronary vascular eNOS activity. A pressure-overload may cause severer left ventricular hypertrophy and dysfunction in eNOS null mice than in wild-type mice. iNOS-derived NO has detrimental effects on the myocardium. NO plays an important role in regulating the angiogenesis and slowing the interstitial fibrosis of the obstructed kidney. In unilateral ureteral obstruction, the expression of eNOS was decreased in the affected kidney. In triply n/i/eNOS null mice, nephrogenic diabetes insipidus developed along with reduced aquaporin-2 abundance. In chronic kidney disease model of subtotal-nephrectomized rats, treatment with NOS inhibitors decreased systemic NO production and induced left ventricular systolic dysfunction (renocardiac syndrome).

Nonobstructive Bilateral Hydronephrosis & Hydroureter from Nephrogenic Diabetes Insipidus with a Novel Mutation of AQP2 Gene (p.A123G)

Nephrogenic diabetes insipidus (NDI) can cause nonobstructive hydronephrosis. Congenital NDI (CNDI) is caused by a genetic mutation. This case report presents a 12-year-old girl who was incidentally diagnosed with nonobstructive hydronephrosis due to NDI caused by AQP2 gene mutation after being evaluated for microscopic hematuria found on routine health examination at school. The patient's medical and family history was unremarkable, and she complained of nocturia only at the time of the clinic visit. Bilateral hydronephrosis on abdominal ultrasonography prompted a water deprivation test, leading to diagnosis of NDI. Genetic study confirmed p.Asn (AAC)123Ser (AGC) in exon 2 of the AQP2 gene. Polyuria and hydronephrosis improved following arginine-vasopressin therapy. CNDI responsive to treatment should be considered as a possible cause of nonobstructive hydroureter.

Analysis of AVPR2 gene mutation in a pedigree affected with congenital nephrogenic diabetes insipidus / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To detect potential mutation in a pedigree affected with congenital nephrogenic diabetes insipidus (NDI).</p><p><b>METHODS</b>Clinical data of a male patient affected with NDI was collected. Genomic DNA was extracted from peripheral blood samples from the patient and five family members. The whole coding region of the arginine vasopressin receptor 2 (AVPR2) gene was amplified by PCR and directly sequenced.</p><p><b>RESULTS</b>The patient presented polyuria and polydipsia postnatally. Computerized tomography revealed bilateral hydronephrosis and hydroureter. The patient was responsive to hydrochlorothiazide but not to desmopressin. DNA analysis identified a hemizygous missence mutation c.295 T>C in exon 2 of the AVPR2 gene in the proband. His mother and grandmother were both heterozygous for the same mutation.</p><p><b>CONCLUSION</b>The congenital NDI in the patient was probably due to mutation of the AVPR2 gene.</p>

Altered Nitric Oxide System in Cardiovascular and Renal Diseases / 전남의대학술지

Nitric oxide (NO) is synthesized by a family of NO synthases (NOS), including neuronal, inducible, and endothelial NOS (n/i/eNOS). NO-mediated effects can be beneficial or harmful depending on the specific risk factors affecting the disease. In hypertension, the vascular relaxation response to acetylcholine is blunted, and that to direct NO donors is maintained. A reduction in the activity of eNOS is mainly responsible for the elevation of blood pressure, and an abnormal expression of iNOS is likely to be related to the progression of vascular dysfunction. While eNOS/nNOS-derived NO is protective against the development of atherosclerosis, iNOS-derived NO may be proatherogenic. eNOS-derived NO may prevent the progression of myocardial infarction. Myocardial ischemia/reperfusion injury is significantly enhanced in eNOS-deficient animals. An important component of heart failure is the loss of coronary vascular eNOS activity. A pressure-overload may cause severer left ventricular hypertrophy and dysfunction in eNOS null mice than in wild-type mice. iNOS-derived NO has detrimental effects on the myocardium. NO plays an important role in regulating the angiogenesis and slowing the interstitial fibrosis of the obstructed kidney. In unilateral ureteral obstruction, the expression of eNOS was decreased in the affected kidney. In triply n/i/eNOS null mice, nephrogenic diabetes insipidus developed along with reduced aquaporin-2 abundance. In chronic kidney disease model of subtotal-nephrectomized rats, treatment with NOS inhibitors decreased systemic NO production and induced left ventricular systolic dysfunction (renocardiac syndrome).

Congenital nephrogenic diabetes insipidus with end-stage renal disease

No abstract available.

Genetic analysis of a congenital nephrogenic diabetes insipidus pedigree / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>As an X-linked recessive way, arginine vasopressin receptor 2 (AVPR2) gene mutation resulted in a hereditary disease - congenital nephrogenic diabetes insipidus (CNDI). We found a suspect clinical CNDI pedigree. In order to identify the genetic etiology, we performed the genetic analysis.</p><p><b>METHODS</b>The clinical features of the proband and his family members were recorded. The laboratory tests and imaging inspections were analyzed. The water deprivation and pituitrin loading test were performed in the proband and his brother. The genomic DNA of all the members of the pedigree was extracted and then PCR amplification on AVPR2 gene was carried out. Sequencing in both directions was performed to identify mutation on AVPR2 gene.</p><p><b>RESULTS</b>Both the proband and his brother were diagnosed as CNDI, meanwhile the other members of this pedigree were normal. No severe biochemical abnormality was found in the two CNDI patients. Both the patients had moderate urinary retention, severe megaloureter and hydronephrosis, and mild renal insufficiency. Two mutations of AVPR2 gene were discovered in the 3rd exon in the patients, a silent mutation L309L and a nonsense mutation R337X. The AVPR2 gene R337X mutation was co-segregated with CNDI. R337X mutation was not a reported mutation in the mainland of China.</p><p><b>CONCLUSION</b>The AVPR2 gene R337X mutation was also a genetic etiology of CNDI patients in the mainland of China.</p>

A case of primary aldosteronism combined with acquired nephrogenic diabetes insipidus

Aldosterone-producing adrenal adenoma can induce various clinical manifestations as a result of chronic exposure to aldosterone. We report a rare case of a 37-year-old man who complained of general weakness and polyuria. He was diagnosed with aldosterone-producing adrenal adenoma and nephrogenic diabetes insipidus. Aldosterone enhances the secretion of potassium in the collecting duct, which can lead to hypokalemia. By contrast, nephrogenic diabetes insipidus, which manifests as polyuria and polydipsia, can occur in several clinical conditions such as acquired tubular disease and those attributed to toxins and congenital causes. Among them, hypokalemia can also damage tubular structures in response to vasopressin. The patient's urine output was > 3 L/d and was diluted. Owing to the ineffectiveness of vasopressin, we eventually made a diagnosis of nephrogenic diabetes insipidus. Laparoscopic adrenalectomy and intraoperative kidney biopsy were subsequently performed. The pathologic finding of kidney biopsy revealed a decrease in aquaporin-2 on immunohistochemical stain.

Channelopathies / 소아과

Channelopathies are a heterogeneous group of disorders resulting from the dysfunction of ion channels located in the membranes of all cells and many cellular organelles. These include diseases of the nervous system (e.g., generalized epilepsy with febrile seizures plus, familial hemiplegic migraine, episodic ataxia, and hyperkalemic and hypokalemic periodic paralysis), the cardiovascular system (e.g., long QT syndrome, short QT syndrome, Brugada syndrome, and catecholaminergic polymorphic ventricular tachycardia), the respiratory system (e.g., cystic fibrosis), the endocrine system (e.g., neonatal diabetes mellitus, familial hyperinsulinemic hypoglycemia, thyrotoxic hypokalemic periodic paralysis, and familial hyperaldosteronism), the urinary system (e.g., Bartter syndrome, nephrogenic diabetes insipidus, autosomal-dominant polycystic kidney disease, and hypomagnesemia with secondary hypocalcemia), and the immune system (e.g., myasthenia gravis, neuromyelitis optica, Isaac syndrome, and anti-NMDA [N-methyl-D-aspartate] receptor encephalitis). The field of channelopathies is expanding rapidly, as is the utility of molecular-genetic and electrophysiological studies. This review provides a brief overview and update of channelopathies, with a focus on recent advances in the pathophysiological mechanisms that may help clinicians better understand, diagnose, and develop treatments for these diseases.