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

An adolescent boy with essential hypernatremia, absent corpus callosum, mental retardation, hypodipsia, and partial diabetes insipidus with "inappropriate" ADH regulation and secretion was studied regarding factors controlling ADH and neurophysin release. Persistent hyperosmolality was noted while on 100 mEq sodium intake daily. Endogenous vasopressin activity was demonstrated after prolonged water deprivation. Hypertonic saline infusion produced increased volumes but dilute urine. Aqueous pitressin increased urinary osmolality, decreased serum osmolality, urine flow rate, and free water clearance. Stable water diuresis was induced by water loading and on normal saline infusion. Nicotine-stimulated neurophysin remained unexpectedly low and below the level of detectability when sampled during the physiologic studies, whereas oestrogen-stimulated neurophysin was elevated during oestrogen stimulation, water loading, and orthostasis procedures. Plasma vasopressin was suppressed with water loading but remained suppressed 90 min after tilt table testing. These data indicate impairment of the osmoreceptor mechanism: however, since the patient had a normal response of oestrogen-stimulated neurophysin, that part of the neurohypophysis appears intact. Chlorpropamide was effective in alleviating the hyperosmolar state acutely and maintained normal osmolar concentrations during two years of therapy.
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PMID:Essential hypernatraemia, antidiuretic hormone and neurophysin secretion: response to chlorpropamide. 746

Mental retardation (MR) is generally considered one of the main complications of congenital nephrogenic diabetes insipidus (NDI). However, psychometric studies of NDI patients are scarce and outdated. In the present study, 17 male NDI patients underwent psychological evaluation. Total intelligence quotient of 14 patients was within (n = 13) or above (n = 1) the normal range, 1 patient had an intelligence score between -1 and -2 standard deviations (S.D.) and 2 young patients had a general cognitive index more than 2 S.D. below the norm. Attention deficit hyperactivity disorder criteria were met by 8 out of 17 patients and scores on short-term memory were low in 7 out of 10. No relation between test performances and age at diagnosis or hypernatremia could be found, with the exception of a negative correlation between age at start of therapy and verbal IQ in one age group. Although several explanations for an association between MR and NDI can be postulated, it seems that the current prevalence of MR among patients with this disease is considerably lower than suggested in literature.
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PMID:Cognitive and psychosocial functioning of patients with congenital nephrogenic diabetes insipidus. 874 26

To study the phenotypic spectrum and management of holoprosencephaly (HPE), we reviewed the findings of eight children with HPE from 3 to 10 years of age, who underwent intervention programs and rehabilitation at our center. One patient had alobar HPE, three semilobar HPE, and four lobar HPE. All patients had postnatal growth retardation, and seven showed a decreased BMI (< 25% tile). All patients had severe developmental delay and mental retardation (DQ < 40), showing no obvious correlation between their severity and the type of HPE. Neurologically seven patients had spasticity (3 spastic quadriplegia, 2 spastic diplegia, 2 mixed-type), except one patient with a 7q deletion [46,XY,del(7) (q35)] who had generalized hypotonia. Seven had variable types of seizures. All patients had feeding difficulties and were assessed by speech-language therapists. Four patients required tube feeding, four had gastroesophageal reflux disease. Recurrent respiratory tract infection was common. Three patients had abnormal serum sodium concentration (1 diabetes insipidus, 1 idiopathic hypernatremia, 1 hyponatremia). No family history of HPE was elicited. In conclusion, patients with HPE should be followed up closely for complications such as feeding difficulty, malnutrition, seizures, spasticity, infection, and osmoreceptor-hypothalamus-hypophyseal axis abnormalities.
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PMID:[Clinical spectrum and management of holoprosencephaly]. 1091 68

A 4-year-old, male Labrador retriever, weighing 27 kg, presented with abrupt clinical signs including mental retardation, circling and head pressing. The dog never ingested water by choice. An adipsia of the dog was persisted and developed to hypernatremia with artifactual hyperchloremia. Serial endocrine results and image findings were suggestive of a hypothyroidism. The dog revealed the presence of antithyroid antibodies in the cerebrospinal fluid and serum. With the administration of levothyroxine sodium, his neurologic signs were alleviated within the first week of treatment and adipsia was also resolved.
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PMID:Adipsic hypernatremia in a dog with antithyroid antibodies in cerebrospinal fluid and serum. 1767 8

Congenital nephrogenic diabetes insipidus (CNDI) is a rare disorder caused by mutations of the arginine vasopressin (AVP) V2 receptor or aquaporin 2 (AQP2) genes. The current study presented the case of CNDI in a 1-month-old male with a novel mutation in the AQP2 gene. The patient was referred due to the occurrence of hypernatremia and mild-intermittent fever since birth. An AVP stimulation test was compatible with CNDI as there was no significant response to desmopressin. Molecular genetic analysis demonstrated two mutations in exon 1 of the AQP2 gene: C to T transition, which resulted in a missense mutation of 108Thr (ACG) to Met (ATG); and a 127, 128 delCA, which resulted in a deletion mutation of glutamine in position 43 at codon CAG as the first affected amino acid, with the new reading frame endign in a termination codon at position 62. The molecular genetic analysis of the parents showed that the missense mutation was inherited maternally and the deletion mutation was inherited paternally. The parents showed no signs or symptoms of CNDI, indicating autosomal recessive inheritance. The 108Thr (ACG) to Met (ATG) mutation was confirmed as a novel mutation. Therefore, the molecular identification of the AQP2 gene has clinical significance, as early recognition of CNDI in infants that show only non-specific symptoms, can be facilitated. Thus, repeated episodes of dehydration, which may cause physical and mental retardation can be avoided.
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PMID:Congenital nephrogenic diabetes insipidus with a novel mutation in the aquaporin 2 gene. 2494 15