Experimental pharmacological approaches to reverse impaired awareness of hypoglycemia-a review.

The colossal global burden of diabetes management is compounded by the serious complication of hypoglycemia. Protective physiologic hormonal and neurogenic counterregulatory responses to hypoglycemia are essential to preserve glucose homeostasis and avert serious morbidity. With recurrent exposure to hypoglycemic episodes over time, these counterregulatory responses to hypoglycemia can diminish, resulting in an impaired awareness of hypoglycemia (IAH). IAH is characterized by sudden neuroglycopenia rather than preceding cautionary autonomic symptoms. IAH increases the risk of subsequent sudden and severe hypoglycemic episodes in patients with diabetes. The postulated causative mechanisms behind IAH are complex and varied. It is therefore challenging to identify a single effective therapeutic strategy. In this review, we closely examine the efficacy and feasibility of a myriad of pharmaceutical interventions in preventing and treating IAH as described in clinical and preclinical studies. Pharmaceutical agents outlined include N-acetyl cysteine, GABA A receptor blockers, opioid receptor antagonists, AMP activated protein kinase agonists, potassium channel openers, dehydroepiandrosterone, metoclopramide, antiadrenergic agents, antidiabetic agents and glucagon.

Internal Carotid Artery Aneurysm Mimicking a Pituitary Adenoma: A Case Report and Review of the Literature.

Background/Objective: A thrombosed internal carotid artery (ICA) aneurysm mimicking a pituitary adenoma can be catastrophic if unrecognized. We report a unique case of the rare presentation of ICA aneurysms masquerading as pituitary adenomas, which can preserve pituitary function when treated early. Case Report: A 54-year-old man with type 2 diabetes, aortic valve replacement, and stroke presented with sudden onset severe headache and left eye pain. Left third nerve palsy was noted. Laboratory studies showed low thyroid-stimulating hormone, follicle-stimulating hormone, luteinizing hormone, testosterone, and insulin-like growth factor 1 levels and baseline, post-30-minute, and post-60-minute cortisol levels of 16, 17, and 14 µg/dL, respectively, after adrenocorticotropic hormone stimulation. Magnetic resonance imaging of the pituitary revealed a heterogeneously enhancing 2.0 × 2.1 × 2.1-cm sellar/suprasellar mass with peripheral enhancement abutting the left cavernous sinus. Given the acute third nerve palsy without visual defects and magnetic resonance imaging findings, other sources of sellar occupying etiology were suspected. Therefore, carotid cerebral angiography was performed and revealed a mostly thrombosed left ICA aneurysm projected into the sellar/suprasellar region. The patient underwent successful endovascular treatment with a resolution of the cranial nerve palsy and hormonal abnormalities at 3-month follow-up. Discussion: Our case demonstrates the importance of swift recognition of ICA aneurysms masquerading as pituitary adenomas. Early recognition and treatment may lead to the complete resolution of presenting symptoms and hormonal deficiencies. Conclusion: Clinicians should have a high index of suspicion for ICA aneurysm in the differential diagnosis for a sellar mass. Careful evaluation is essential because misdiagnosis may lead to catastrophic consequences.

A rare case of isolated IgG4-related hypophysitis with Rathke's cleft cyst presenting as panhypopituitarism.

Summary: We report a rare case of biopsy-proven isolated immunoglobulin G4 (IgG4)-related hypophysitis and Rathke's cleft cyst (RCC) presenting as panhypopituitarism. A 54-year-old Caucasian female presented with symptoms of slurred speech, altered mental status, polyuria and polydipsia and was found to have panhypopituitarism. Brain MRI showed a suprasellar mass with suspected intralesional hemorrhage. She underwent trans-sphenoidal resection due to MRI evidence of compression of the optic chiasm and left optic nerve. Preoperatively, she was started on hydrocortisone, levothyroxine and desmopressin. Histopathology demonstrated a RCC with adjacent lymphoplasmacytic hypophysitis with numerous IgG4-immunoreactive plasma cells. Hydrocortisone was stopped at 10 months after confirming hypothalamic-pituitary-adrenal (HPA)-axis recovery and desmopressin was stopped at 1 year. There was recurrence of a cystic mass at 1 year follow-up. Over 4 years of follow-up, she continued to require levothyroxine, and the mass remained stable in size. In order to begin to understand how this case's unique histopathological presentation influences clinical presentation, pituitary imaging and prognosis, we present an accompanying literature review. Learning points: Isolated IgG4 hypophysitis and coexisting Rathke's cleft cyst is a rare condition, which presents a diagnostic challenge. Recognizing its characteristic features can assist with early recognition and initiation of therapy to promote optimal outcomes. Further studies investigating the mechanisms promoting co-occurrence of these entities and their effect on prognosis are needed.