RHABDOMYOLYSIS SECONDARY TO RAPID CORRECTION OF HYPONATREMIA IN A PATIENT WITH PSYHCOGENIC POLYDIPSIA.

Patients with chronic schizophrenia and psychosis are more prone to develop hyponatremia. Hyponatremia could be due to medications e.g. antidepressants/antipsychotics or secondary to psychogenic polydipsia. They often present with altered consciousness, seizures and falls. Rapid correction of hyponatremia in patients with psychogenic polydipsia has been associated to cause rhabdomyolysis, an under-recognized yet serious condition which if left untreated can result in various complications e.g. acute kidney injury, electrolyte abnormalities. We report a case of young patient who had background illness of schizophrenia and presented to department with severe hyponatremia secondary to psychogenic polydipsia and was eventually diagnosed as case of rhabdomyolysis due to rapid correction of hyponatremia. Objective of case report is to highlight the correct diagnosis of underlying cause of hyponatremia and challenges associated with managing rhabdomyolysis with IV fluids that can result in worsening of hyponatremia, hence emphasizing the importance of close monitoring of sodium levels and measurement of creatine kinase in any patient who presents with severe hyponatremia, particularly in the presence of other risk factors for rhabdomyolysis and consideration of careful fluid administration strategies in relation to the relative onset and risk of over-correcting hyponatremia.

1p36 is a preferential target of chromosome 1 deletions in astrocytic tumours and homozygously deleted in a subset of glioblastomas.

Astrocytic, oligodendroglial and mixed gliomas are the commonest gliomas in adults. They have distinct phenotypes and clinical courses, but as they exist as a continuous histological spectrum, differentiating them can be difficult. Co-deletions of total 1p and 19q are found in the majority of oligodendrogliomas and considered as a diagnostic marker and a prognostic indicator. The 1p status of astrocytomas has not yet been thoroughly examined. Using a chromosome 1 tile path array, we investigated 108 adult astrocytic tumours for copy number alterations. Total 1p deletions were rare (2%), however partial deletions involving 1p36 were frequently identified in anaplastic astrocytomas (22%) and glioblastomas (34%). Multivariate analysis showed that patients with total 1p deletions had significantly longer survival (P=0.005). In nine glioblastomas homozygous deletions at 1p36 were identified. No somatic mutations were found among the five genes located in the homozygously deleted region. However, the CpG island of TNFRSF9 was hypermethylated in 19% of astrocytic tumours and 87% of glioma cell lines. TNFRSF9 expression was upregulated after demethylation of glioma cell lines. Akt3 amplifications were found in four glioblastomas. Our results indicate that 1p deletions are common anaplastic astrocytomas and glioblastomas but are distinct from the 1p abnormalities in oligodendrogliomas.

Genomic organization and amplification of the human desmosomal cadherin genes DSC1 and DSC3, encoding desmocollin types 1 and 3.

The desmosomal cadherins comprise the desmocollins and desmogleins and are involved in epithelial cell-cell adhesion. There are three desmocollins (DSC 1-3) and three desmogleins (DSG 1-3) that are expressed in a tissue- and development-specific manner. Desmosomal proteins have been implicated in a number of disorders characterized by loss of cell-cell adhesion and trauma-induced skin fragility. Therefore, the desmocollins are potential candidates for genodermatoses involving epithelial tissues. In order to screen the entire DSC1 and DSC3 genes, we have characterized their intron-exon organization. The DSC1 gene comprises 17 exons spanning approximately 33 kb on 18q12.1, and the DSC3 gene comprises 17 exons spanning approximately 49 kb on 18q12.1. We have also developed a comprehensive PCR-based mutation detection strategy for desmocollins 1, 2, and 3 using primers placed on flanking introns followed by direct sequencing of the PCR products.