Congenital renal diabetes insipidus caused by aquaporin 2 gene mutation in siblings: 2 cases report and literature review / 中国综合临床

Objective:To improve clinicians' understanding of congenital nephrogenital diabetes insipidus (CNDI) and to reduce missed and misdiagnosis. Methords 　Based on the literature, the clinical data and gene mutation of 2 patients with CNDI who were admitted to the Department of Endocrinology and Metabolism of the First Affiliated Hospital of Henan University of Science and Technology on July 30, 2020 were analyzed retrospectively. Results:(1) The presentee, 4 years old, had irritable thirst, polydipsia and polyuria for more than 3 years. The sister, 2.5 years old, had irritable thirst, polydipsia and polyuria for more than 2 years. The clinical diagnosis was “CNDI”, and the symptoms improved after treatment with hydrochlorothiazide. (2) The genetic test revealed that the congenital nephrogenic uremia and her sister had a heterozygous mutation of c.170A>C (p.Q57P) and c.211G>A (p.Vl71M) in the aquaporin-2 gene, and the mother carried the AQP2 gene. c.170A>C(p.Q57P) mutation.Conclusion:CNDI is a rare disease. Early diagnosis and treatment can improve the prognosis of patients to the greatest extent, and prenatal diagnosis can guide eugenics.

Lithium and endocrine dysfunction / Litio y disfunción endocrina

Abstract Lithium carbonate is a commonly prescribed drug for bipolar disorders. In addition to its action on the central nervous system, lithium has systemic effects on multiple organs such as kidney, heart, motor end plate, thyroid and parathyroid glands. It can cause hypothyroidism, hyperthyroidism, goiter and oph thalmopathy by different mechanisms. It increases intrathyroid iodine content or compete for iodine transport, resulting in low iodine uptake by the thyroid. It also inhibits the coupling of iodotyrosine residues to form iodothy ronines and inhibits the release of T4 and T3. Lithium has direct actions on parathyroid glands by antagonizing the calcium sensing receptor, which may induce hypercalcemia or even hyperparathyroidism, requiring surgery in some cases. Furthermore, it inhibits the expression of aquaporins, mainly aquaporin 2, in the renal collecting tubule by unknown mechanisms leading to nephrogenic diabetes insipidus. This adverse effect is usually reversible after drug withdrawal. However, some patients may present irreversible kidney damage due to chronic interstitial nephropathy.

Resumen El carbonato de litio es un fármaco que se prescribe comúnmente para el tratamiento de trastornos bipolares. Además de su acción sobre el sistema nervioso central, el litio tiene repercusiones sistémicas, afectando a múltiples órganos como el riñón, el corazón, la placa motora terminal y glándulas tiroides y paratiroides. Puede causar hipotiroidismo, hipertiroidismo, bocio y oftalmopatía por diferentes mecanismos; también aumentar el contenido de yodo intratiroideo o competir por el transporte de yodo, lo que resulta en una baja captación tiroidea de yodo. Inhibe el acoplamiento de residuos de yodotirosina para formar yodotironinas e inhibe la liberación de T4 y T3. Tiene acciones directas sobre las glándulas paratiroides antagonizando el receptor sensor de calcio, lo que puede inducir hipercalcemia e incluso hiperparatiroidismo, y puede requerir cirugía en algunos casos. Inhibe la expresión de acuaporinas en el túbulo colector renal, prin cipalmente acuaporina 2, por mecanismos que aún no se conocen, produciendo diabetes insípida nefrogénica; este efecto adverso suele ser reversible tras la suspensión del fármaco. Sin embargo, algunos pacientes pueden presentar daño renal irreversible por nefropatía intersticial crónica.

Depleción corporal de magnesio durante el embarazo por nefropatía hipercalcemica. Reporte de caso y revisión de la literatura / Magnesium depletion secondary to hypercalcémie nephropathy during pregnancy: Case report and literatura review

Resumen El magnesio sérico es el "ion olvidado" en la práctica médica: la mayoría de veces no se tiene en cuenta en los estudios clínicos, sus alteraciones tienden a ser ignoradas y su aproximación terapéutica no está definida de forma adecuada. La sintomatologia producto de la hipomagnesemia es inespecífica y su aproximación diagnostica es compleja. Se presenta el caso de una paciente con hipomagnesemia sintomática severa asociada a daño renal por hipercalcemia durante la gestación.

Abstract Serum magnesium is the «forgotten ion¼ in medical practice. Most of the time it is not taken into account in clinical studies, its alterations tend to be ignored and its therapeutic approach is not well defined. The symptomatology produced by hypomagnesemia is nonspecific and its diagnostic approach is complex. We present the case of a pregnant patient with symptomatic hypomagnesemia secondary to renal damage due to hypercalcemia.

X-linked congenital renal diabetes insipidus caused by AVPR2 gene mutation: a case report / 天津医药

@#Objective A case of congenital renal diabetes insipidus caused by mutation of arginine vasopressin receptor 2 (AVPR2) gene was reported to explore the clinical significance of AVPR2 gene mutation in congenital nephrotic diabetes insipidus and improve the understanding of the disease. Methods The clinical data of proband and his parents were retrospectively analyzed, and the related literature was reviewed. All exons of AVPR2 were amplified by PCR, and the amplified products were purified and sequenced in two directions. Results The clinical manifestations of the children were recurrent fever and hypernatremia, and hyperchloremia was difficult to correct. There was no abnormality in pituitary nuclear magnetic resonance in the child at the beginning. Short T1 signal disappeared in the posterior pituitary lobe after reexamination. Central diabetes insipidus was not excluded from clinical practice. However, vasopressin test supported renal diabetes insipidus, which caused troubles in clinical diagnosis. The treatment of vasopressin acetate tablets was ineffective. The results of gene analysis confirmed that mutations were found in the subregion of AVPR2 gene in the proband: c.359T (thymine)>G (guanine) caused amino acid changes: p.Met120Arg, which was located on the X chromosome, and the mother of the patient was the carrier of the mutation of AVPR2 gene. Clinical application of hydrochlorothiazide and amiloride in the treatment of the child with urinary volume significantly reduced, confirmed as congenital renal diabetes insipidus. Conclusion Congenital renal diabetes insipidus in infants and young children is rare and its clinical manifestations are not specific. It can only be manifested by repeated fever and electrolyte disturbance, which causes troubles in clinical diagnosis. AVPR2 gene detection can be used for screening and gene diagnosis of congenital renal diabetes insipidus.

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.

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.

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).

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：2 cases report of brothers and review / 临床儿科杂志

Objective Congenital nephrogenic diabetes insipidus (CNDI) is a rare disease, the aim of this article is to help better understanding of this disease. Methods The clinical features, genetic analysis and treatments of two siblings with CNDI were retrospectively analyzed, and related literatures were reviewed. Results Both brothers had polydispia, polyuria and low concentrate urine continuously, and they both had a mutation in AQP 2 conifrmmed with Sanger sequencing. This novel frame shift mutation caused arginine of 254 to histidine, and prolonged AQP 2 protein. Conclusions Gene analysis can help diagnosis of CNDI. Amiloride is useful option for treatment.

Diabetes insípida nefrogénica / Nephrogenic diabetes insipidus

La hormona antidiurética arginina vasopresina (AVP) es liberada de la hipófisis, y regula la reabsorción de agua en las células principales del túbulo colector renal. La unión de la AVP al receptor tipo 2 de la AVP en la membrana basolateral induce la translocación de los canales acuosos de la acuaporina-2 hacia la membrana apical de las células principales de los túbulos colectores, induciendo la permeabilidad al agua de la membrana. Lo anterior da como resultado la reabsorción de agua en el túbulo colector de la nefrona, bajo la influencia de un gradiente osmótico. La diabetes insípida nefrogénica es causada por la resistencia parcial o total al efecto de la AVP. La diabetes insípida nefrogénica congénita es una alteración asociada con mutaciones en los genes AVPR2 o AQP2, ocasionando la incapacidad del paciente para concentrar la orina. La diabetes insípida nefrogénica adquirida o secundaria puede ser causada por desbalances electrolíticos (hipercalcemia, hipokalemia), enfermedades renales o extrarrenales y fármacos (toxicidad por litio). En este artículo se revisan las causas, manifestaciones clínicas, diagnóstico y tratamiento de los pacientes con diabetes insípida nefrogénica. También, con base en la comprensión de los mecanismos íntimos de la alteración, se exploran nuevas estrategias terapéuticas.

The anti-diuretic hormone arginine-vasopressin (AVP) is released from the pituitary and regulates water reabsorption in the principal cells of the kidney collecting duct. Binding of AVP to the arginine-vasopressin receptor type-2 in the basolateral membrane leads to translocation of aquaporin-2 water channels to the apical membrane of the principal cells of the collecting duct, inducing water permeability of the membrane. This results in water reabsorption in the collecting duct of the nephron following an osmotic gradient. Nephrogenic diabetes insipidus is caused by partial or complete renal resistance to the effects of AVP. Congenital nephrogenic diabetes insipidus is a disorder associated with mutations in either the AVPR2 or AQP2 gene, causing the inability of patients to concentrate their urine. Acquired nephrogenic diabetes insipidus can be caused by electrolyte imbalances (e.g., hypercalcemia, hypokalemia), renal/extra-renal diseases and drugs (e.g., lithium toxicity). This article reviews the causes, clinical manifestations, diagnosis and treatment of patients with nephrogenic diabetes insipidus. Based on more in-depth mechanistic understanding, new therapeutic strategies are current being explored.

El litio y su relación con la acuaporina-2 y el canal de sodio ENaC / Lithium and its relation with the epithelial sodium channel and aquaporin-2

Desde hace más de cuarenta años que el litio es usado para el tratamiento de la enfermedad bipolar; recientes estudios sugieren también su utilidad en el trastorno cognitivo mínimo tipo amnésico. El litio es filtrado en el glomérulo y un 65-75% del mismo es reabsorbido en el túbulo contorneado proximal y en el asa ascendente de Henle por el transportador Na+, K+, 2Cl- y vía paracelular. Una pequeña fracción del litio entra en las células principales del túbulo colector por medio del canal epitelial de sodio sensible al amiloride (ENaC) localizado en la membrana apical de la célula. Luego de 10- 20 años de tratamiento con litio los enfermos pueden desarrollar poliuria, acidosis tubular e insuficiencia renal crónica que puede terminar en una forma de diabetes que no responde a la arginina vasopresina llamada diabetes insípida nefrogénica. Se cree que estas fallas renales son consecuencias de una reducción en el número de moléculas de acuaporina 2 en la membrana apical. Las causas para esto son complejas. El litio es un poderoso inhibidor de la isoforma beta de la enzima glicógeno sintetasa quinasa y esto está asociado a una menor actividad de la adenilato ciclasa que lleva a una disminución en la concentración intracelular de cAMP. Esto finalmente interferiría con la síntesis de nuevas moléculas de acuaporina 2 y con el tráfico de ellas desde la zona subapical de la célula hacia la membrana celular, causando la disminución en la reabsorción de agua en la parte distal del nefrón.

For more than 40 years lithium has been used to treat bipolar disorder and recent trials suggest a potential efficacy also in the treatment of the amnestic mild cognitive impairment. Lithium is filtered by the glomerulus and 65% - 75% of the filtered amount is reabsorbed along the proximal tubule and in the thick ascending limb of Henle's loop by the Na+, K+, 2Cl- transporter and via paracellular. A small fraction of lithium is reabsorbed in the collecting duct's principal cells through the epithelial Na channel (ENaC) located on the apical side of the cells. Polyuria, renal tubular acidosis and chronic renal failure are the most frequent adverse effects of lithium after 10-20 years of treatment and these alterations can reach to a vasopressin nonresponding form of diabetes insipidus entity called nephrogenic diabetes insipidus. It is believed that the molecular mechanisms of these renal changes are related to a reduction in the number of aquaporin-2 inserted in the apical membrane of the cells. The causes of this are complex. Lithium is a powerful inhibitor of the enzyme glycogen synthase kinase 3β and this is associated with a lower activity of adenylate cyclase with a reduction in the cAMP levels inside of the cells. The latter may interfere with the synthesis of aquaporin-2 and also with the traffic of these molecules from the subapical site to membrane promoting the impairment of water reabsorption in the distal part of the kidney.

A Case of Lithium-Induced Nephrogenic Diabetes Insipidus and Rhabdomyolysis / 대한내과학회지

A 59-year-old woman was admitted to our hospital with polydipsia and general weakness. She had a 30-year history of bipolar disorder and was being treated with risperidone (4 mg/day) and lithium carbonate (1,200 mg/day). During her time in hospital, her urine output and serum osmolality increased, and her urine osmolality decreased. She was found to have myoglobulinuria, an elevated creatine kinase level, and abnormal renal function. Based on these findings, the patient was diagnosed with diabetes insipidus and rhabdomyolysis secondary to lithium therapy. After fluid therapy and the withdrawal of lithium, her clinical symptoms improved significantly. Her urine volume decreased gradually after treatment with amiloride. The effects of lithium on the muscle system are unknown. Hyperosmolarity caused by lithium-induced diabetes insipidus is considered a contributing factor in rhabdomyolysis.

A Case of Lithium-Induced Nephrogenic Diabetes Insipidus and Rhabdomyolysis / 대한내과학회지

A 59-year-old woman was admitted to our hospital with polydipsia and general weakness. She had a 30-year history of bipolar disorder and was being treated with risperidone (4 mg/day) and lithium carbonate (1,200 mg/day). During her time in hospital, her urine output and serum osmolality increased, and her urine osmolality decreased. She was found to have myoglobulinuria, an elevated creatine kinase level, and abnormal renal function. Based on these findings, the patient was diagnosed with diabetes insipidus and rhabdomyolysis secondary to lithium therapy. After fluid therapy and the withdrawal of lithium, her clinical symptoms improved significantly. Her urine volume decreased gradually after treatment with amiloride. The effects of lithium on the muscle system are unknown. Hyperosmolarity caused by lithium-induced diabetes insipidus is considered a contributing factor in rhabdomyolysis.

A Familial Case of Nephrogenic Diabetes Insipidus Associated with a Mutation of the AVPR2 Gene

Nephrogenic diabetes insipidus is a rare genetic renal disease characterized by insensitivity of the kidney to the anti-diuretic effect of vasopressin in spite of elevated serum anti-diuretic hormone (ADH). Failure of the kidney to respond to ADH results in impaired osmoregulation and water reabsorption of the kidney, therefore, nephrogenic diabetes insipidus presents with a large amount of hypotonic polyuria, polydipsia, and dehydration. We report our experience of two familial cases of nephrogenic diabetes insipidus in brothers both having c.910+1delG in intron 2 of the AVPR2 gene with the brief review of related literatures.

A case of congenital nephrogenic diabetes insipidus: his pedigree and clinical evaluation / 中华内分泌代谢杂志

A case of arginine vasopressin receptor 2 ( AV PR2 ) mutation in a boy with congenital nephrogenic diabetes insipidus was reported.Genomic DNA of the boy and his family members was extracted.The entire coding region of the AVPR2 gene were amplified by PCR.The amplified products were purified and sequenced.The results were compared with the normal one of the gene bank.The impact of the mutation on AVPR2 structure was discussed with respect to homology structure model.The analysis identified a T to G transition in exon 2 of the AVPR2 gene,resulting in substitution of leucine for arginine at amino acid residue 168.Furthermore,the patient′s mother and sister were heterozygous for this mutation,and the father was normol.

Differential Diagnosis of Hereditary Nephrogenic Diabetes Insipidus with Desmopressin Infusion Test.

Purpose The causes of hereditary nephrogenic diabetes insipidus (HNDI) are the mutations in the arginine vasopressin V2 receptor gene (AVPR2) (90%) and aquaporin 2 gene (AQP2) (10%). Although it is possible to perform mutation analysis where available, differentional diagnosis at clinical bases remains valuable. Methods In this report we present two cases of HNDI diagnosed at clinical bases with a desmopressin infusion test as AQP2 gene mutations. The results were verified by genetic analysis to stress that a desmopressin infusion test is valuable for differential diagnosis of HNDI. Results With a desmopressin infusion test, factor VIII levels were increased up to 219% and 214% respectively, establishing the presence of V2 receptor. With direct sequencing of the AQP2 gene, a previously described splicing mutation in a new codon (380) and a new frameshift mutation were determined in case 1 and case 2 respectively. Conclusion It is concluded that the desmopressin infusion test is a simple and reliable method for the diagnosis and differential diagnosis of HNDI in early childhood.

A case of Bartter syndrome type I with atypical presentations / 소아과

Bartter syndrome (BS) is an autosomal recessively inherited rare renal tubular disorder characterized by hypokalemic metabolic alkalosis and hyperreninemic hyperaldosteronism with normal to low blood pressure due to a renal loss of sodium. Genetically, BS is classified into 5 subtypes according to the underlying genetic defects, and BS is clinically categorized into antenatal BS and classical BS according to onset age. BS type I is caused by loss-of-function mutations in the SLC12A1 gene and usually manifests as antenatal BS. This report concerns a male patient with compound heterozygous missense mutations on SLC12A1 (p.C436Y and p.L560P) and atypical clinical and laboratory features. The patient had low urinary sodium and chloride levels without definite metabolic alkalosis until the age of 32 months, which led to confusion between BS and nephrogenic diabetes insipidus (NDI). In addition, the clinical onset of the patient was far beyond the neonatal period. Genetic study eventually led to the diagnosis of BS type I. The low urinary sodium and chloride concentrations may be caused by secondary NDI, and the later onset may suggest the existence of a genotype-phenotype correlation.

Diabetes insípida en pediatría: serie clínica y revisión de la literatura / Diabetes insipidus in pediatrics

Introduction: Diabetes insipidus (DI) is a syndrome characterized by polyuria and polydipsia secondary to a decreased secretion or action of the antidiuretic hormone (ADH). An early diagnosis is essential. Diagnosis is made by measuring plasma and urinary osmolarity and their changes under water deprivation and after DDAVP administration. Objective: Lo describe the clinical, radiological characteristics as well as the initial treatment of eight children with DI, 3 of them nephrogenic DI (DIN) and 5 with central DI. Methods: A Retrospective, descriptive study in DI patients under control at the Catholic University of Chile and Sotero del Rio Hospital between 1998-2008 is presented. Clinical files were evaluated collecting clinical, epidemiologic, biochemical and image data. Serum (Sosm) and urinary osmolarity (Uosm) were registered. DI was diagnosed with a Sosm > 300 and Usm < 600 mOsm/L. Central DI was defined as the inability to reach a Uosm > 600 or a 50 percent-increase after DDAVP treatment. Otherwise DI was classified as DIN. Results: Eight patients (5 males) were studied. Chief complaints were polydipsia/polyuria (5/8), hyperthermia (2/8), and failure to grow (1/8). MRI showed endocraneal lesion in all patients with Central DI. All of these utilized oral or inhalatory DDAVP treatment. Patients with Nephrogenic DI were trated with Hydrochlrothiazide. Conclusion: Polydipsia, polyuria, hyperthermia with hypernatremia are suggestive of DI in the first year of life. Water deprivation test is diagnostic in differentiating Central and Nephrogenic DI. MRI is an essential diagnostic tool in CDI. Manegement should be multidisciplinary, including a pediatician, nephrologist, endocrinologist and nutricionist.

Introducción: La diabetes insípida (DI) se caracteriza por poliuria y polidipsia, secundario a una disminución de la secreción o acción de la hormona antidiurética. Su diagnóstico precoz es fundamental. Objetivo: Describir las características clínicas, radiológicas y tratamiento inicial de una serie de ocho pacientes con DI. Diseño: Estudio descriptivo-restrospectivo. Universo: Pacientes con DI evaluados en la Universidad Católica de Chile y Hospital Dr. Sótero del Río entre 1998-2008. Pacientes y Métodos: Desde la ficha clínica se analizaron variables clínicas, epidemiológicas, bioquímicas e imágenes. Se determinó Osmolaridad sérica (OsmS) y urinaria (OsmU). Se consideró DI sí la OsmS > 300 mOsm con OsmU < 600 mOsm, Di-central (DIC) sí posterior a DDAVP la OsmU aumento > 50 por ciento ó > 600 mOsm, de los contrario se clasificó como nefrogénica (DIN). Resultados: Se reclutaron ocho pacientes con DI (5 varones), fueron DIN 3/8. El motivo de consulta fue: polidipsia-poliuria (5/8), hipertermia (2/8) y talla baja (1/8). La RNM mostró lesión intracraneana en todos los pacientes con DIC: nodulo hipofisiario, aracnoidocele selar, Histiocitosis X, germinoma y un paciente sin se±al de neurohipófisis. Los sujetos con DIC usaron DDAVP inhalatoria (4) y oral (1). Los sujetos con DIN usaron hidroclorotiazida. Conclusión: Polidipsia, poliuria, hipertermia con hipernatremia y falla de medro en lactantes son sugerentes de DI. La prueba de deprivación hídrica es fundamental en la diferenciación de DIC y DIN. La RNM cerebral es una herramienta diagnóstica imprescindible en la DIC. El tratamiento de estos pacientes debe ser multidiciplinario interactuando pediatra, nefrólogo, endocrinólogo y nutricionista.

Congenital Nephrogenic Diabetes Insipidus Presented with Bilateral Hydronephrosis: Genetic Analysis of V2R Gene Mutations

Most cases of hydronephrosis are caused by urinary tract obstruction. However, excessive polyuric syndrome rarely gives rise to non-obstructive hydronephrosis, megaureter, and a distended bladder. The authors report here on two cases of congenital nephrogenic diabetes insipidus (NDI) with severe bilateral hydronephrosis and megaureter. It is Interesting that the patients were symptomless except for their polyuria, and they both presented with bilateral hydronephrosis. Fluid deprivation testing revealed the presence of AVP resistant NDI. Gene analysis for these patients showed the AVP receptor 2 (V2R) missense mutations (Q225X and S126F), which have previously been reported on in other studies. We made the diagnosis of NDI by using a physiologic test, and we confirmed it by mutation analysis of the V2R gene.

A Case of Congenital Nephrogenic Diabetes Insipidus Presenting Fever in Neonatal Period / 대한주산의학회잡지

Congenital nephrogenic diabetes insipidus (NDI) is a rare disorder of the kidney characterized by the in ability to concentrate urine despite normal or elevated plasma concentration of the antidiuretic hormone agent vasopressin (AVP). We describe a case of congenital nephrogenic diabetes insipidus presenting with mild fever . The 3-day-old baby boy was admitted with mild fever. He has 6 members with DI in his family and his laboratoty finding showed hypernatremia, increased serum osmolarity and low level of urine specific gravity. Throughout the water deprivation test and the vasopressin test, he has been diagnosed as congenital NDI. Urinary free water loss was improved after treatment with hydrochlorothiazide and low salt formula. At the age 4 months, the infant has demonstrated normal growth and neurodevelopmental milestones. An early diagnosis of congenital NDI is very important, since the proper adequate management can prevent hyperosmolarity which might induce the delayed mental and physical development.