Iatrogenic adrenal insufficiency in adults.

Iatrogenic adrenal insufficiency (IAI) is the most common form of adrenal insufficiency in adult patients, although its overall exact prevalence remains unclear. IAI is associated with adverse clinical outcomes, including adrenal crisis, impaired quality of life and increased mortality; therefore, it is imperative that clinicians maintain a high index of suspicion in patients at risk of IAI to facilitate timely diagnosis and appropriate management. Herein, we review the major causes, clinical consequences, diagnosis and care of patients with IAI. The management of IAI, particularly glucocorticoid-induced (or tertiary) adrenal insufficiency, can be particularly challenging, and the provision of adequate glucocorticoid replacement must be balanced against minimizing the cardiometabolic effects of excess glucocorticoid exposure and optimizing recovery of the hypothalamic-pituitary-adrenal axis. We review current treatment strategies and their limitations and discuss developments in optimizing treatment of IAI. This comprehensive Review aims to aid clinicians in identifying who is at risk of IAI, how to approach screening of at-risk populations and how to treat patients with IAI, with a focus on emergency management and prevention of an adrenal crisis.

Adrenal insufficiency is common amongst kidney transplant recipients receiving maintenance prednisolone and can be predicted using morning cortisol.

BACKGROUND: Long-term glucocorticoid therapy is a key component of immunosuppression for kidney transplant recipients (KTRs), leading to significant cumulative glucocorticoid exposure. The aims of this study are to investigate the prevalence of adrenal insufficiency (AI) in KTRs taking prednisolone and to develop a screening algorithm to identify patients at the highest risk of AI. METHODS: In this cross-sectional cohort study, 67 KTRs receiving prednisolone underwent a short synacthen test (SST) and measurement of cumulative glucocorticoid exposure. RESULTS: A total of 72% (n = 48) of participants failed the SST. Participants with AI had a higher daily prednisolone dose (4.9 versus 4.2 mg/day; P = .002) and greater cumulative glucocorticoid exposure (289 versus 111 mg/kg; P = .03) than those with intact adrenal function. Participants with AI had lower baseline cortisol than participants with intact adrenal function (143 versus 303 nmol/L; P < .001). Morning cortisol of >288 nmol/L predicted a normal SST with 100% specificity [95% confidence interval (CI) 92-100] and 70% sensitivity (95% CI 56-78%), therefore excluding AI. CONCLUSIONS: Our results suggest KTRs are at a higher risk for AI than previously reported. A morning serum cortisol measurement is a useful screening tool in this cohort, reducing the need for stimulatory testing by 44%. KTRs with AI need education regarding glucocorticoid sick rules, similar to patients with other forms of AI.

Bladder Paraganglioma Presenting as Post-Micturition Syncope.

A 22-year-old woman presented with a 12-year history of intensifying paroxysms of anxiety, palpitations and recurrent syncope following micturition. The patient was referred to endocrinology upon discovery of hypertension. An extended family history revealed metastatic phaeochromocytoma and paraganglioma in two grand-uncles. Clinical examination revealed hypertension, with a mean 24-hour ambulatory blood pressure of 150/100 mmHg. Supine plasma normetanephrines were markedly elevated with a raised 3-methoxytyramine, while plasma metanephrines were normal. Computed tomography identified a 4.4 cm mass at the right inferolateral margin of the bladder wall. Scintigraphic imaging confirmed unifocal bladder lesion uptake with no additional metastatic lesions. Following pre-operative alpha blockade, the patient underwent a partial cystectomy. Histology confirmed a paraganglioma, and SDHB staining was lost in neoplastic cells consistent with an SDHB-related paraganglioma. Plasma normetanephrine, 3-methoxytyramine and blood pressure returned to normal postoperatively. Genetic screening identified a germline heterozygous SDHB gene variant c.723C>G. Bladder paragangliomas are a rare but important differential to consider when investigating post-micturition syncope. An extended family history should be sought and suspicion for a genetic cause should be raised, especially when the condition presents at a young age. This is the first reported case describing phaeochromocytoma or paraganglioma with the SDHB gene variant c.723C>G. LEARNING POINTS: Bladder paragangliomas are a rare neuroendocrine tumour which should be considered when assessing patients with haematuria and hypertension, headache, palpitations, sweating and facial pallor with micturition.This case highlights the importance of a thorough clinical history with an extended family history and examination in the setting of micturition syncope, which can rarely occur with bladder paraganglioma.Young age at presentation, a family history of phaeochromocytoma and paraganglioma (PPGL), unusual paraganglioma location, mutifocality and aggressive disease should raise the suspicion for a genetic predisposition to PPGL.

Diagnosis and Management of Central Diabetes Insipidus in Adults.

Central diabetes insipidus (CDI) is a clinical syndrome which results from loss or impaired function of vasopressinergic neurons in the hypothalamus/posterior pituitary, resulting in impaired synthesis and/or secretion of arginine vasopressin (AVP). AVP deficiency leads to the inability to concentrate urine and excessive renal water losses, resulting in a clinical syndrome of hypotonic polyuria with compensatory thirst. CDI is caused by diverse etiologies, although it typically develops due to neoplastic, traumatic, or autoimmune destruction of AVP-synthesizing/secreting neurons. This review focuses on the diagnosis and management of CDI, providing insights into the physiological disturbances underpinning the syndrome. Recent developments in diagnostic techniques, particularly the development of the copeptin assay, have improved accuracy and acceptability of the diagnostic approach to the hypotonic polyuria syndrome. We discuss the management of CDI with particular emphasis on management of fluid intake and pharmacological replacement of AVP. Specific clinical syndromes such as adipsic diabetes insipidus and diabetes insipidus in pregnancy as well as management of the perioperative patient with diabetes insipidus are also discussed.

Approach to the Patient: Hyponatremia and the Syndrome of Inappropriate Antidiuresis (SIAD).

Hyponatremia is the most common electrolyte disturbance seen in clinical practice, affecting up to 30% of acute hospital admissions, and is associated with significant adverse clinical outcomes. Acute or severe symptomatic hyponatremia carries a high risk of neurological morbidity and mortality. In contrast, chronic hyponatremia is associated with significant morbidity including increased risk of falls, osteoporosis, fractures, gait instability, and cognitive decline; prolonged hospital admissions; and etiology-specific increase in mortality. In this Approach to the Patient, we review and compare the current recommendations, guidelines, and literature for diagnosis and treatment options for both acute and chronic hyponatremia, illustrated by 2 case studies. Particular focus is concentrated on the diagnosis and management of the syndrome of inappropriate antidiuresis. An understanding of the pathophysiology of hyponatremia, along with a synthesis of the duration of hyponatremia, biochemical severity, symptomatology, and blood volume status, forms the structure to guide the appropriate and timely management of hyponatremia. We present 2 illustrative cases that represent common presentations with hyponatremia and discuss the approach to management of these and other causes of hyponatremia.

Propylthiouracil-induced antineutrophil cytoplasmic antibody-associated vasculitis and agranulocytosis in a patient with Graves' disease.

SUMMARY: This case is the first to describe a patient who experienced concomitant agranulocytosis and anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis as an adverse effect of propylthiouracil treatment for Graves' disease. A 42-year-old female with Graves' disease presented to the emergency department (ED) with a 2-week history of fevers, night sweats, transient lower limb rash, arthralgia, myalgia and fatigue. She had been taking propylthiouracil for 18 months prior to presentation. On admission, agranulocytosis was evident with a neutrophil count of 0.36 × 109/L and immediately propylthiouracil was stopped. There was no evidence of active infection and the patient was treated with broad-spectrum antibodies and one dose of granulocyte colony-stimulation factor, resulting in a satisfactory response. On further investigation, ANCAs were positive with dual positivity for proteinase 3 and myeloperoxidase. There was no evidence of end-organ damage secondary to vasculitis, and the patient's constitutional symptoms resolved completely on discontinuation of the drug precluding the need for immunosuppressive therapy. LEARNING POINTS: Continued vigilance and patient education regarding the risk of antithyroid drug-induced agranulocytosis is vital throughout the course of treatment. ANCA-associated vasculitis is a rare adverse effect of antithyroid drug use. Timely discontinuation of the offending drug is vital in reducing end-organ damage and the need for immunosuppressive therapy in drug-induced ANCA-associated vasculitis. Similarities in the pathogenesis of agranulocytosis and drug-induced ANCA-associated vasculitis may offer insight into an improved understanding of vasculitis and agranulocytosis.

Risk factors and long-term consequences of new-onset diabetes after renal transplantation.

BACKGROUND: New-onset diabetes after transplant (NODAT) confers risk of diabetes-related complications as well as a threat to graft function and overall patient survival. The reported incidence of NODAT varies from 14 to 37% in renal transplant recipients worldwide; however, NODAT is yet to be studied in the Irish renal transplant population. AIMS: Primary aims of this project were to estimate the incidence, to determine associated risk factors and to assess the long-term consequences of NODAT on graft survival and patient survival in the Irish renal transplant population. METHODS: Retrospective data collection of 415 renal transplant recipients over a 12-year period was performed to record presence of NODAT, patient characteristics and perioperative management. Preoperative screening was reviewed in a subgroup of patients to determine concordance with the International Consensus Guidelines. Statistical analysis was performed using Kaplan-Meier survival functions estimating NODAT detection over time, graft and patient survival. Risk factor association was determined using Cox proportional-hazards models. RESULTS: NODAT incidence was 10.2% in the first 5 years of post-transplant. Risk factors for developing NODAT were recipient age and body weight. Risk of NODAT was highest in the first year of post-transplant and conferred decreased patient survival; however, it did not significantly affect graft survival. Only seven patients of a subgroup of 21 patients who developed NODAT had preoperative testing for diabetes. CONCLUSIONS: NODAT incidence in the Irish renal transplant population is slightly below international figures. This project has highlighted current deficits in the national transplant guidelines for the detection of NODAT and NODAT-related risk factors.

Metabolic encephalopathy secondary to diabetic ketoacidosis: a case report.

INTRODUCTION: Metabolic encephalopathy is a rare but potentially devastating complication of diabetic ketoacidosis (DKA). This case highlights the dramatic cognitive decline of a young man due to metabolic encephalopathy complicating DKA. The aims of this case report are to highlight metabolic encephalopathy as a complication of DKA and to explore the current research in diabetic related brain injury. The importance of investigation and treatment of reversible causes of encephalopathy is also demonstrated. CASE PRESENTATION: A 35-year-old man with a background of type 1 diabetes mellitus (T1DM) and relapsing remitting multiple sclerosis (RRMS) presented to the emergency department (ED) in a confused and agitated state. Prior to admission he worked as a caretaker in a school, smoked ten cigarettes per day, took excess alcohol and smoked cannabis twice per week. Following initial investigations, he was found to be in DKA. Despite timely and appropriate management his neurological symptoms and behavioural disturbance persisted. Neuroimaging revealed temporal lobe abnormalities consistent with an encephalopathic process. The patient underwent extensive investigation looking for evidence of autoimmune, infective, metabolic, toxic and paraneoplastic encephalopathy, with no obvious cause demonstrated. Due to persistent radiological abnormalities a temporal lobe biopsy was performed which showed marked astrocytic gliosis without evidence of vasculitis, inflammation, infarction or neoplasia. A diagnosis of metabolic encephalopathy secondary to DKA was reached. The patient's cognitive function remained impaired up to 18 months post presentation and he ultimately required residential care. CONCLUSIONS: Metabolic encephalopathy has been associated with acute insults such as DKA, but importantly, the risk of cerebral injury is also related to chronic hyperglycaemia. Mechanisms of cerebral injury in diabetes mellitus continue to be investigated. DKA poses a serious and significant neurological risk to patients with diabetes mellitus. To our knowledge this is the second case report describing this acute complication.

Autonomic alterations as a clinical manifestation of encephalopathy associated with autoimmune thyroid disease.

Encephalopathy associated with autoimmune thyroid disease (EAATD), also known as Hashimoto's encephalopathy, is a rare neurological condition that may occur in patients with clinical or sub-clinical autoimmune thyroid disease. The pathogenesis of EAATD has been not clearly elucidated yet. The diagnostic criteria include neurological or psychiatric symptoms, high levels of anti-thyroid antibodies, and exclusion of other possible causes of encephalopathy. In the large majority of cases, EAATD patients respond to immunosuppressant therapies, in particular to corticosteroids. We report the case of a patient with Hashimoto's thyroiditis and recurrent manifestations of encephalopathy over the previous few years responding to corticosteroid treatment. The patient presented with language and cognitive impairment, ataxia, and neurovegetative/autonomic symptoms. She was euthyroid with mildly raised anti-thyroid peroxidase antibodies. An extensive diagnostic work-up, including electroencephalogram, brain magnetic resonance, hormonal assessment, and an exhaustive panel of antibodies possibly associated with autoimmune encephalopathy, was carried out and excluded other possible etiologies of encephalopathy. The diagnosis of EAATD possibly affecting the hypothalamus and/or the neurovegetative regulatory centers was made and treatment with prednisolone was timely commenced with a dramatic and rapid improvement with progressive normalization of the symptoms. To the best of our knowledge, this is the first report of neurovegetative/autonomic alterations in the setting of EAATD.