Primary Polydipsia in Children: Two Case Reports

Primary polydipsia (PP) is marked by an increase in thirst, and most often presents in patients with psychiatric illnesses. Although uncommon in children, we experienced cases of PP in a 15-month-old boy and a 5-year-old girl. Both were admitted to the hospital with symptoms of polydipsia and polyuria that appeared 1–3 months before admission. Brain magnetic resonance imaging in both patients was normal. A water restriction test was performed after hospitalization and showed normal results. The symptoms improved after the parents were instructed to implement water-intake restriction for 2 weeks. Our report provides useful information for the treatment of PP in children.

Psychogenic polydipsia and hyponatremia – A side effect of psychosis: a review with a case report / Polidipsia psicogênica e hiponatremia – Efeito colateral da psicose: revisão com relato de caso

ABSTRACT Primary polydipsia, or psychogenic polydipsia, is a condition that results in considerable morbidity and mortality. In psychiatric patients, psychogenic polydipsia and the syndrome of inappropriate antidiuretic hormone secretion may cause hyponatremia. In the 1970s, it was recognized that antipsychotics such as tiotixene and haloperidol could impair the excretion of a free water load. There are also several case reports of drug-induced hyponatremia in patients using atypical drugs suggesting that these probably can also impair water balance and induce hyponatremia. Case report and review of relevant literature are reported in this article. Psychogenic polydipsia is a common cause of hyponatremia among individuals with chronic mental illness. A case of severe hyponatremia caused by psychogenic polydipsia is described involving a female patient with an adult lifelong history of chronic mental illness diagnosed as schizoaffective disorder. After switching her antipsychotic medication to clozapine water ingestion was normalized as well as sodium levels and her psychotic symptoms improved. Primary polydipsia occurs commonly with schizophrenia and other mental diseases and can cause hyponatremia. PPD may present as an acute psychotic state or as inexplicable emergence of seizures. Appropriate, timely clinical assessment with special attention to thirst, fluid intake, and urine output is essential. Proper treatment may include drug withdrawal and fluid and saline restriction. Once corrected, some pharmacological agents can be tried. The article illustrates the importance of the diagnosis of psychogenic polydipsia given its electrolyte disturbances and life threatening situations.

RESUMO A polidipsia primária ou polidipsia psicogênica (PDP) é uma condição que se traduz em altas taxas de morbilidade e mortalidade. Nos doentes psiquiátricos, a PDP e a síndrome da secreção inapropriada do hormônio antidiurético (SIADH) podem resultar em hiponatremia. Nos anos 1970, foi reconhecido que alguns antipsicóticos como o tiotixeno e o haloperidol podiam comprometer a excreção de água livre. Existem ainda diversos casos reportados de hiponatremia iatrogênica em pacientes medicados com antipsicóticos atípicos sugerindo que essa classe farmacológica pode igualmente resultar em hiponatremia. Um caso clínico e uma revisão sobre o tema são reportados neste artigo. A polidipsia psicogênica é uma causa comum de hiponatremia entre os indivíduos com doença mental crônica. Um caso de hiponatremia grave causada por polidipsia psicogênica é descrito envolvendo uma paciente do sexo feminino com antecedentes de perturbação esquizoafetiva. Após alteração da sua medicação antipsicótica para clozapina, observou-se normalização na ingestão hídrica bem como nos níveis de sódio e melhoria da sintomatologia psicótica. A PDP ocorre comumente em doentes esquizofrênicos ou com outras perturbações psiquiátricas e pode resultar em hiponatremia. Um correto diagnóstico com especial atenção a sede, ingestão hídrica e débito urinário é essencial. O tratamento pode incluir a retirada de fármacos e restrição hídrica e salina. Uma vez corrigida, alguns agentes farmacológicos podem ser utilizados.

PLASMA ARGININE VASOPRESSIN ESTIMATION IN THE DIAGNOSIS OF NON-OSMOTIC POLYURIA / 中华内分泌代谢杂志

The plasma arginine vasopressin (AVP) level was measured by RIA in 19 patients with polyuria and polydipsia, and the AVP measurement was compared with indirect tests. The AVP levels were very low in 13 patients with central diabetes insipidus and normal in 6 patients with primary polydipsia. The direct assay was correspondent to the indirect criteria in 89% of the patients. We concluded that the use of AVP assay improves accuracy in the differential diagnosis of polyuria, and is important in the diagnosis of these diseases.