Prolonged Hypokalemia and Delayed Diagnosis of Primary Aldosteronism: Clinical Course and Risk Factors.

INTRODUCTION: Primary Aldosteronism (PA) is a common cause of hypertension. However, diagnosis is often delayed, leading to poorer clinical outcomes. Hypokalemia with hypertension is characteristic of PA, and is an indication for screening. We evaluated if patients with PA had prolonged hypokalemia before diagnosis, the subsequent biochemical/clinical control, and factors associated with delayed diagnosis. METHODS: Our study included all PA patients with hypokalemia diagnosed between 2001 to 2022. Delayed diagnosis was defined as duration of hypokalemia of >1 year from first occurrence, to first evaluation by a PA specialist. Patients were reassessed post-adrenalectomy using the Primary Aldosteronism Surgery Outcomes criteria. We performed multivariable analysis to assess for factors associated with delayed diagnosis. RESULTS: Among 240 patients with PA who presented with hypokalemia, 122 (51%) patients had delayed diagnosis, with prolonged hypokalemia of median duration 4.5 (2.4-7.5) years. Patients with delayed diagnosis were older, had longer duration of hypertension, higher pill burden, lower renal function and more prevalent cardiovascular disease. Factors associated with delayed diagnosis included older age, presence of hyperlipidaemia, and less severe hypokalemia (serum potassium >3.0mmol/L). Compared to patients with early diagnosis, a lower proportion of those with delayed diagnosis underwent adrenal vein sampling (73% vs 58%), P<0.05. Sixty of 118 (50.8%) non-delayed, and 39 of 122 (32.0%) patients with delayed diagnosis underwent surgery. CONCLUSION: Despite manifestation of hypokalemia, many patients with PA fail to be promptly screened. Greater emphasis in hypertension guidelines, and efforts to improve awareness of PA amongst primary care physicians are urgently needed.

11C-Metomidate PET-CT versus adrenal vein sampling to subtype primary aldosteronism: a prospective clinical trial.

OBJECTIVE: Adrenal vein sampling (AVS) is recommended to subtype primary aldosteronism, but it is technically challenging. We compared 11C-Metomidate-PET-computed tomography (PET-CT) and AVS for subtyping of primary aldosteronism. METHODS: Patients with confirmed primary aldosteronism underwent both AVS and 11C-Metomidate PET-CT (post-dexamethasone). All results were reviewed at a multidisciplinary meeting to decide on final subtype diagnosis. Primary outcome was accuracy of PET versus AVS to diagnosis of unilateral primary aldosteronism based on post-surgical biochemical cure. Secondary outcome was accuracy of both tests to final subtype diagnosis. RESULTS: All 25 patients recruited underwent PET and successful AVS (100%). Final diagnosis was unilateral in 22 patients, bilateral in two and indeterminate in one due to discordant lateralization. Twenty patients with unilateral primary aldosteronism underwent surgery, with 100% complete biochemical success, and 75% complete/partial clinical success. For the primary outcome, sensitivity of PET was 80% [95% confidence interval (95% CI): 56.3-94.3] and AVS was 75% (95% CI: 50.9-91.3). For the secondary outcome, sensitivity and specificity of PET was 81.9% (95% CI: 59.7-94.8) and 100% (95% CI: 15.8-100), and AVS was 68.2% (95% CI: 45.1-86.1) and 100% (95% CI: 15.8-100), respectively. Twelve out of 20 (60%) patients had both PET and AVS lateralization, four (20%) PET-only, three (15%) AVS-only, while one patient did not lateralize on PET or AVS. Post-surgery outcomes did not differ between patients identified by either test. CONCLUSION: In our pilot study, 11C-Metomidate PET-CT performed comparably to AVS, and this should be validated in larger studies. PET identified patients with unilateral primary aldosteronism missed on AVS, and these tests could be used together to identify more patients with unilateral primary aldosteronism. VIDEO ABSTRACT: http://links.lww.com/HJH/B918.

Severe Symptomatic Hypophosphataemia as a Complication of Parenteral Iron Replacement.

Parental iron replacement is given to patients with severe iron deficiency or intolerance to oral iron. Hypophosphataemia has been reported to occur as a complication of parental iron replacement, and is postulated to be related to the carbohydrate moieties used in the parenteral preparations. Hypophosphataemia is under-diagnosed as symptoms such as fatigue, muscle weakness and poor effort tolerance mimic anaemia. Severe hypophosphataemia (<0.32 mmol/l) can result in significant complications such as confusion, rhabdomyolysis and arrhythmias. We report a patient with recurrent admissions for non-specific symptoms attributed to iron deficiency anaemia who received multiple doses of parenteral ferric carboxymaltose (FCM). He was found to have severe hypophosphataemia, with further evaluation showing increased renal phosphate wasting and elevated serum levels of fibroblast-growth-factor 23 (FGF23). FCM was stopped and he was given high-dose oral iron supplementation, with no further episodes of hypophosphataemia. LEARNING POINTS: The carbohydrate moieties used in parenteral iron preparations are different, and may have a dose-dependent relationship with the development of hypophosphataemia.The mechanism by which hypophosphataemia occurs after parenteral iron replacement is related to increased serum levels of FGF23, which increases renal phosphate wasting.The serum phosphate levels of patients receiving parenteral iron replacement (especially ferric carboxymaltose or iron polymaltose) should be routinely monitored for hypophosphataemia, which is an under-diagnosed complication.

Bilateral Aldosterone Suppression in Patients With Right Unilateral Primary Aldosteronism and Review of the Literature.

INTRODUCTION: Adrenal vein sampling (AVS) identifies unilateral primary aldosteronism but may occasionally show paradoxically low aldosterone-cortisol ratios bilaterally. Postulated reasons include venous anomalies, fluctuating aldosterone secretion, or superselective cannulation. We report our findings in patients who underwent repeat AVS and reviewed the current literature. METHODS: We performed a retrospective observational study of patients undergoing AVS in an experienced high-volume tertiary center over a 5-year period. RESULTS: From 2015 to 2019, 61 patients underwent sequential cosyntropin-stimulated AVS and all had bilateral successful cannulation (100%). Four of 61 (6.6%) patients had bilaterally low aldosterone-cortisol ratios. Three patients underwent repeat AVS, with all 3 cases demonstrating right-sided lateralization and cure of disease postadrenalectomy. Right-sided disease was also more common in other reports. This may be due to inadvertent superselective cannulation of the short right adrenal vein, resulting in sampling of the adjacent normal gland. Cortisol results cannot detect this problem. In 1 patient, computed tomography venography excluded any accessory right adrenal veins. In another patient, repeat bilateral simultaneous unstimulated AVS was done, and measurements of metanephrines aided in accurately identifying right-sided lateralization. CONCLUSION: In addition to technical difficulties in cannulating the right adrenal vein, we also have to avoid performing superselective cannulation inadvertently. In cases of inconclusive AVS, repeat sampling may identify patients with potentially curable unilateral primary aldosteronism. The role of corticotropin stimulation and metanephrines measurements during repeat AVS requires further study.

Implementing electronic handover: interventions to improve efficiency, safety and sustainability.

PROBLEM: Effective handovers are critical for patient care and safety. Electronic handover tools are increasingly used today to provide an effective and standardized platform for information exchange. The implementation of an electronic handover system in tertiary hospitals can be a major challenge. Previous efforts in implementing an electronic handover tool failed due to poor compliance and buy-in from end-users. A new electronic handover tool was developed and incorporated into the existing electronic medical records (EMRs) for medical patients in Singapore General Hospital (SGH). INITIAL ASSESSMENT: There was poor compliance by on-call doctors in acknowledging electronic handovers, and lack of adherence to safety rules, raising concerns about the safety and efficiency of the electronic handover tool. Urgent measures were needed to ensure its safe and sustained use. SOLUTION: A quality improvement group comprising stakeholders, including end-users, developed multi-faceted interventions using rapid PDSA (P-Plan, D-Do, S-Study, A-Act ) cycles to address these issues. IMPLEMENTATION: Innovative solutions using media and online software provided cost-efficient measures to improve compliance. EVALUATION: The percentage of unacknowledged handovers per day was used as the main outcome measure throughout all PDSA cycles. Doctors were also assessed for improvement in their knowledge of safety rules and their perception of the electronic handover tool. LESSONS LEARNT: An electronic handover tool complementing daily clinical practice can be successfully implemented using solutions devised through close collaboration with end-users supported by the senior leadership. A combined 'bottom-up' and 'top-down' approach with regular process evaluations is crucial for its long-term sustainability.

Hypereosinophilic syndrome with large intracardiac thrombus.

As the nonspecific clinical presentation of hypereosinophilic syndrome (HES) may mimic many multisystemic diseases, it often presents as a diagnostic challenge. Herein, we report the case of a 60-year-old man who presented with progressive heart failure symptoms and eosinophilia. Despite extensive diagnostic evaluation, no underlying cause was found. Transthoracic echocardiography revealed a large left ventricular thrombus, which is suggestive of hypereosinophilic cardiac involvement. The patient was started on steroids and responded clinically and haematologically.

An eight year review of exercise-related cardiac arrests.

INTRODUCTION: Exercise-related cardiac arrest is uncommon, however it is devastating when it occurs in otherwise healthy adults. This study aims to identify the characteristics of exercise-related cardiac arrest in the study population and estimate the overall survival rate. MATERIALS AND METHODS: This is a retrospective observational study of exercise-related cardiac arrest in Singapore. Patients with exercise-related out of hospital cardiac arrest (OHCA) were selected from the Cardiac Arrest and Resuscitation Epidemiology (CARE) database, which is a prospective cardiac arrest registry, derived from ambulance records, emergency department and hospital discharge records. Patient characteristics, cardiac arrest circumstances and outcomes were studied. RESULTS: Fifty-fi ve cases of exercise-related cardiac arrests were identified from December 2001 to January 2008. Mean age was 50.9 years with a male predominance of 96.4%. Eighty percent of the exercise-related cardiac arrests were witnessed, however only 58.2% of the patients received bystander cardiopulmonary resuscitation (CPR). The fi rst presenting rhythm was ventricular fibrillation (VF) in 40% of the patients, followed by asystole (38.2%). Of 96.2% of the patients who died from cardiac causes, coronary artery disease was the main etiology for 54%. The 30-day survival rate was 5.5%. CONCLUSION: We found that exercise-related cardiac arrest causes significant mortality in our community. Increased CPR training among the public, easy access to defibrillators and faster emergency medical service (EMS) response time could improve the outcome of exercise-related cardiac arrests. A comprehensive pre-participation screening for competitive exercises should be outlined for primary prevention of exercise-related cardiac arrest. A better reporting system for exercise-related cardiac arrest is needed.