Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

An unusual association of Bardet-Biedl syndrome with cystinuria was described in one patient. A 21-year-old male was admitted to hospital because of renal failure, severe deterioration of visual acuity, polydactyly, brachydactyly, and mental retardation. Laboratory investigations revealed a serum creatinine of 292 mumol/L (3.3 mg/dL) and a GFR of 25 mL/min per 1.73 m2. Quantitative ion exchange chromatography demonstrated an increased urinary excretion rate of cystine, lysine, arginine, and ornithine. The ophthalmologic examination showed a severe atypical retinal dystrophy. Visual acuity was severely deteriorated and the patient could only count the examining physician's fingers. The patient had been previously evaluated at the age of 7 years for polyuria, polydipsia, and growth failure. His workup at that time demonstrated nephrogenic diabetes insipidus, normal GFR, and a urinary amino acid pattern consistent with the cystinuric phenotype. There was mental retardation notwithstanding the normal ophthalmologic examination. Intravenous pyelography showed calyceal clubbing, calyceal cysts, and lobulated renal outlines of the fetal type. The patient was evaluated again at the age of 13 years for deterioration of visual acuity and the ophthalmologic examination showed an atypical retinal dystrophy, with sparse pigmentation, central and peripheral atrophy, attenuated vessels, and marked optic disk pallor. To our knowledge the association of Bardet-Biedl syndrome with cystinuria has never been reported. It is unlikely that cystinuria may have contributed to the kidney damage. The possibility that mental retardation has been induced or aggravated by cystinuria cannot be excluded.
 ...
PMID:Bardet-Biedl syndrome and cystinuria. 146 12

The syndrome of water intoxication may occur in psychiatric patients and various hypotheses regarding its aetiology have been postulated. Twenty-seven patients in Woodbridge Hospital were found to have this syndrome. The aim of the study was to describe the clinical and biochemical findings of this group of patients. 70.4% had schizophrenia, 25.9% had mental retardation and 3.7% had a history of alcohol dependence. Many of them were on antipsychotic medication. The symptoms of water intoxication included polyuria, nausea, tremors, weight gain, disorientation, coma and fits. A majority of the patients had hyponatraemia during the acute stages and the osmolality of urine and plasma were correspondingly low. A few patients had abnormalities in electroencephalogram and computerised axial tomography of brain. The management of patients with water intoxication is discussed briefly.
 ...
PMID:Water intoxication in psychiatric patients in Singapore. 239 1

Twenty-one patients with nephronophthisis are described with a follow-up of one to 16 years (mean 9.3 years). In 10 patients, there was a familial incidence. Autosomal recessive appears the likely mode of inheritance with a 20 per cent incidence noted (seven of 35) following correction for the bias of ascertainment by removing the probands. Seven patients had an associated and characteristic retinal degeneration from infancy. Associated neurologic problems, including mental retardation, seizures and cerebellar ataxis, were also seen in some patients. Previously described skeletal abnormalities and hepatic fibrosis were not seen in any of our patients. All presented at an advanced stage of chronic renal failure, usually associated with a history of polydipsia and polyuria from infancy. Renal cysts were noted in only one of the nine patients in whom tissue was obtained by needle biopsy. In seven patients in whom tissue was available at nephrectomy or autopsy, cysts were noted in six although only in two were they localized to the medulla. Eighteen patients have undergone dialysis, and 12 patients have received a renal transplant with no evidence of recurrence of the original disease. Sixteen patients are still alive. Many synonyms for nephronophthisis have appeared, with medullary cystic disease being the most common. Our experience suggests that nephronophthisis is a common cause of chronic renal failure and has commonly associated nonrenal abnormalities.
 ...
PMID:Nephronophthisis. 736 32

The Bardet-Biedl syndrome (BBS), which consists of polydactyly, obesity, mental retardation, pigmentary retinopathy and hypogonadism has been known since 1922, but due to the great similarity to the clinical manifestations of the Laurence-Moon syndrome (LMS) there is a considerable terminological confusion in the medical literature. An attempt is made at clarifying the problem. Four children from two families have been observed. There were inter- and intrafamilial variabilities of the expression and severity of the particular features, but retinopathy and structural and/or functional abnormalities were found in 100%. The combination of the two can serve as an easy clinical screening for diagnosis of the disease. Renal involvement is considered to be a cardinal feature of the syndrome. The most common and earliest symptoms are polydypso-polyuria and reduced concentrating ability, which may lead to some diagnostic difficulties, especially in infancy. Three children have end-stage renal disease and two of them are on maintenance haemodialysis, which they tolerate well.
 ...
PMID:Clinical aspects of renal involvement in Bardet-Biedl syndrome. 827 Mar 81

Branchio-oto-renal syndrome is a rare autosomal dominant disorder of the first and second embryonic branchial arches and the urinary tract. It is characterized in its full expression by branchial fistulas or cysts, preauricular pits, outer, middle and inner ear defects, hearing loss, lachrymal duct stenosis, facial paralysis and mental retardation. Renal anomalies may range from mild hypoplasia to complete absence. Our report demonstrates the patient with classical BOR syndrome and severe renal insufficiency since infancy up to end stage renal failure at 18 years of age caused by bilateral renal hypoplasia. Although no definitive histological diagnosis was made, the clinical findings in our patients, like mild proteinuria, normal blood pressure, polyuria, polydypsia, hyperchloremic acidosis and typical course of renal failure support the diagnosis of oligomeganephronia in this case.
 ...
PMID:[A nineteen year observation of a boy with branchio-oto-renal syndrome and chronic renal failure]. 1143 82

Congenital nephrogenic diabetes insipidus (NDI) is, in most instances, a rare X-linked recessive renal disorder (MIM 304800) characterized by the clinical symptoms of polyuria, polydipsia, and dehydration. The X-linked NDI is associated with mutations of the arginine vasopressin receptor type 2 (AVPR2) gene, which results in resistance to the antidiuretic action of arginine vasopressin (AVP) in the renal tubules and collecting ducts. Identification of mutations in the AVPR2 gene can facilitate early diagnosis of NDI, which can prevent serious complications such as growth retardation and mental retardation. We analyzed three unrelated Chinese NDI families and identified three mutations: R106C, F287L, and R337X. In addition, an A/G polymorphism at cDNA nucleotide position 927 (codon 309L) was identified. A functional expression assay of the R106C and F287L mutants in COS-7 cells revealed that both mutants show significant dysfunction and accumulate intracellular cyclic adenosine monophosphate in response to AVP hormone stimulation. These results facilitate the diagnosis of NDI at the molecular level in the Chinese population, and provide insight into the molecular pathology of NDI.
 ...
PMID:Identification of mutations in the arginine vasopressin receptor 2 gene causing nephrogenic diabetes insipidus in Chinese patients. 1191 4

Hypokalemia is associated with some renal diseases manifested by renal tubular acidosis (type I and II) or by renal tubular syndrome (Bartter's, Gitelman's and Liddle's syndrome). Bartter's syndrome, originally described by Batter and colleagues in 1962, is a set of closely related renal tubular disorders characterized by hypokalemia, hypochloremia, metabolic alkalosis and hyperreninemia with normal blood pressure. The underlying renal abnormality results in excessive urinary losses of sodium, chloride, potassium and calcium. Muscle weakness, polydipsia, polyuria and mental retardation can be also present. Affected children have poor growth rates and they appear malnourished. The article is focused on ethiopathogenesis, laboratory and clinical characteristics and on the treatment of Bartter's syndrome.
 ...
PMID:[Bartter's syndrome--hypokalemic renal tubular syndrome]. 1462 62

The case report describes a young boy with renal, retinal, hepatic and cerebellar involvement in a rare syndrome. He had polyuria, deranged renal functions and cystic lesions in kidneys, which led to the diagnosis of nephronophthisis (NPH). Extra-renal involvement with night blindness, truncal ataxia, mental retardation and hepatosplenomegaly. Thus, every patient with NPH should be carefully examined for extra-renal involvement.
 ...
PMID:Nephronophthisis: a variant. 1592 46

Nephrogenic diabetes insipidus (NDI), which can be inherited or acquired, is characterized by an inability to concentrate urine despite normal or elevated plasma concentrations of the antidiuretic hormone arginine vasopressin (AVP). Polyuria, with hyposthenuria, and polydipsia are the cardinal clinical manifestations of the disease. About 90% of patients with congenital NDI are males with X-linked recessive NDI (OMIM 304800) who have mutations in the arginine-vasopressin receptor 2 (AVPR2) gene that codes for the vasopressin V2 receptor. In about 10% of the families studied, congenital NDI has an autosomal recessive or autosomal dominant mode of inheritance (OMIM 222000 and 125800). In these families, mutations have been identified in the aquaporin-2 gene (AQP2) (OMIM 107777), which codes for the vasopressin-sensitive water channel. Most missense AVPR2 mutations lead to receptors that are trapped intracellularly; a few mutant receptors reach the cell surface but are unable to bind AVP or to properly trigger an intracellular cyclic adenosine monophosphate signal. Similarly, most AQP2 mutant proteins are also misrouted. Prior knowledge of AVPR2 or AQP2 mutations in NDI families and perinatal mutation testing is of direct clinical value because early diagnosis and treatment can avert the physical and mental retardation associated with repeated episodes of dehydration.
 ...
PMID:Nephrogenic diabetes insipidus. 1658 Jun 9

Nephrogenic diabetes insipidus which can be inherited or acquired, is characterized by an inability to concentrate urine despite normal or elevated plasma concentrations of the antidiuretic hormone, arginine-vasopressine (AVP). Polyuria, with hyposthenuria and polydipsia are the cardinal clinical manifestations of the disease. Hypercalcemia, hypokaliemia, lithium administration and chronic renal failure are the principal causes of acquired nephrogenic diabetes insipidus. About 90 percent of patients with congenital nephrogenic diabetes insipidus are males with X-linked recessive nephrogenic diabetes insipidus who have mutations in the arginine-vasopressin receptor 2 (AVPR2) gene that codes for the vasopressin V2 receptor. The gene is located in chromosome region Xq28. In about 10 percent of the families studied, congenital nephrogenic diabetes insipidus has an autosomal recessive or autosomal dominant mode of inheritance. In these cases, mutations have been identified in the aquaporin-2 gene (AQP2), which is located in chromosome region 12q13 and codes for the vasopressin-sensitive water channel. Other inherited disorders with mild, moderate or severe inability to concentrate urine include Bartter's syndrome and Cystinosis. Identification of the molecular defect underlying congenital nephrogenic diabetes insipidus is of immediate clinical significance because early diagnosis and treatment of affected infants can avert the physical and mental retardation associated with episodes of dehydration.
 ...
PMID:[Nephrogenic diabetes insipidus]. 1708 61


1 2 Next >>