Etiological Spectrum with Diagnosis and Prognosis of Central Diabetes Insipidus needs Long Term Followup:A Single Centre Experience

Introduction:Central Diabetes insipidus(CDI)is a rare disorder caused by vasopressin deficiency characterized by the excretion of copious volumes of unconcentrated urine.Objective:To assess the etiological,clinical,biochemical and radiological spectrum of Central DI in our institute and long term follow up of these cases.Material and Methods:32 patients with Central DI admitted in Department of Endocrinology,Guwahati Medical College,Assam in the last 2.5 years were included.Detailed clinical assessment,biochemical evaluation and MRI(Magnetic Resonance imaging)brain were done in all the patients.Central DI without any identifiable cause was considered Idiopathic and those with structural lesion in hypothalamic pituitary region were considered organic.Result:Idiopathic CDI was present in 12(37.5%)patients and 20(62.5%)patients had organic CDI with acute onset of presentation.12(60%)patients with organic CDI present with neurological symptoms but 8(40%)patients had no neurological symptoms even with organic cause.Pituitary dysfunction was common in organic CDI as compared to idiopathic CDI.Paediatric patients commonly present with organic cause for CDI with low cortisol most common hormonal deficit.One patient of idiopathic CDI with normal stalk thickness at baseline presented with clinical and radiological features of LCH(Langerhans cell histiocytosis)on follow up.Conclusion:Organic CDI more likely to have acute onset of presentation than idiopathic CDI and even in absence of neurological features.Paediatric patients commonly have organic cause for CDI.We propose the paramount importance of long-term clinical follow-up and reassessment of endocrine function in patients with CDI for definitive diagnosis of autoimmune and inflammatory causes of idiopathic CDI and timely treatment of pituitary hypofunction.

Caution on diagnosis of idiopathetic central diabetes insipidus

Idiopathetic central diabetes insipidus （CDI） is a heterogeneous hypothalamus-pituitary disease due to the absence or deficiency of arginine vasopressin （AVP）.

Prediabetes and type 2 diabetes implication in central proliferation and neurogenesis

Type 2 diabetes （T2D） is an important risk factor for developing dementias, including Alzheimer＇s disease （AD）. Hyperinsulin- emia and glucose intolerance, as features of T2D, might increase the neurodegeneration process, synaptic loss and brain atrophy, leading to cognitive impairment observed in AD. Also, adult neurogenesis seems to be impaired in AD models. Therefore, we have studied morphological alterations, cell proliferation and neurogenesis in the central nervous system （CNS） from a classical model of T2D, the db/db mouse, and in a prediabetes insulin-resistant model, obtained after long-term high fat diet （HFD） administration to C57B1/6 mice. Db/db mice showed an age-dependent cortical and hippocampal atrophy, whereas in HFD mice cortex and hippocampus were preserved. Neurogen- esis and cell proliferation were increased in young db/db mice, when compared with control mice, whereas no differences were detected in the prediabetic model. We also detected significant correlations between metabolic parameters and central atrophy, altered proliferation and neurogenesis in the central nervous system. Altogether these data support that glycaemia control in elderly patients, could help to control central alterations and improve dementia prognosis.

Diabetes insipidus with impaired vision caused by germinoma and perioptic meningeal seeding:A case report

BACKGROUND Germinoma is a type of germ cell tumor that most frequently arises in the midline axis of the brain.Impaired vision is a clinical manifestation of germinnoma.Although rare,intracranial germinoma seeding to the perioptic arachnoid space is one cause of visual acuity decrease.CASE SUMMARY An 11yearold girl who presented with polyuria and polydipsia and subsequently developed diminution of vision.Imaging showed bilateral heterogeneous enhancement of the optic nerve sheaths and atrophy of the optic nerve,and transsphenoidal biopsy revealed a germinoma.The patient experienced poor visual recovery following chemotherapy and radiotherapy.Germinomas are rare and they are mostly identified in children and adolescents.The manifestations include diabetes insipidus,pituitary dysfunction,visual complaints,etc.The mechanisms that lead to visual loss include intracranial hypertension,compression of optic chiasma,and tumor invasion.A literature review was performed to summarize the cases with a tumor infiltrating the optic nerve.Most of the reported patients were adolescents and presented with anterior pituitary hormone deficiency.Enhancement of optic nerve sheaths and optic disc pallor could be identified in most of the cases.The purpose of this report is to provide awareness that in cases where a germinoma is associated with visual loss,though rare,perioptic meningeal seeding should be taken into consideration.CONCLUSION The case report suggests that children with diabetes insipidus need a complete differential diagnosis.

Manifestations of type 2 diabetes in corneal endothelial cell density,corneal thickness and intraocular pressure

We sought to evaluate central corneal thickness（CCT）,corneal endothelial cell density（ECD）and intraocular pressure（IOP）in patients with type 2 diabetes mellitus（DM）and to associate potential differences with diabetes duration and treatment modality in a prospective,randomized study.We measured ECD,CCT and IOP of125 patients with type 2 DM（mean age 57.1±11.5 years）and compared them with 90 age-matched controls.Measured parameters were analyzed for association with diabetes duration and glucose control modalities（insulin injection or oral medication）while controlling for age.In the diabetic group,the mean ECD（2511±252 cells/mm^2）,mean CCT（539.7±33.6μm）and mean IOP（18.3±2.5 mmHg）varied significantly from those the control group[ECD：2713±132 cells/mm^2（P〈0.0001）,CCT：525.0±45.3μm（P=0.003）and IOP：16.7±1.8 mmHg（P〈0.0001）].ECD was significantly reduced by about 32 cell/mm^2 for diabetics with duration of〉10 years when compared with those with duration of〈10 years（P〈0.05）.CCT was thicker and IOP was higher for diabetics with duration of〉10 years than those with duration of〈10 years（P〉0.05）.None of the measured parameters was significantly associated with diabetes duration and treatment modality（P〉0.05）.In conclusion,subjects with type 2DM exhibit significant changes in ECD,IOP and CCT,which,however,are not correlated with disease duration or if the patients receive on insulin injection or oral medications.

Impact of topical nonsteroidal anti-inflammatory drugs in prevention of macular edema following cataract surgery in diabetic patients

AIM： To evaluate the efficacy of prophylactic administration of topical non-steroidal anti-inflammatory drugs（NSAIDs） on macular edema following cataract surgery in diabetic patients, and to compare between types of NSAIDs（ketorolac tromethamine 0.4% and nepafenac 0.1%）. METHODS： Group 1（control） received artificial tears substitute as a placebo group, group 2（nepafenac） received topical nepafenac 0.1%, and group 3（ketorolac） received topical ketorolac tromethamine 0.4%. Patients were examined postoperatively after completing one week, one month, two months and three months＇ intervals for evaluating cystoid macular edema（CME） development. The main study outcomes were achieving the best corrected visual acuity（BCVA） and change in the central macular thickness（CMT） measured with optical coherence topography（OCT）.RESULTS： Eighty eyes of 76 patients were included in this study. BCVA showed a statistically significant difference at the third month postoperative follow up between the control group and the NSAIDs groups（P=0.04）. There was an increase in the CMT in all cases starting from postoperative first week until third month. CMT showed a statistically significant difference between control group and NSAIDs groups from postoperative first month until third month（P=0.008, 0.027, 0.004）. There was no statistically significant difference between nepafenac and ketorolac groups in BCVA and OCT CMT. CONCLUSION： Prophylactic preoperative and postoperative NSAIDs may have a role in reducing the frequency and severity of CME in diabetic eyes following cataract surgery.