A case study of a liver transplant-treated patient with glycogen storage disease type Ia presenting with multiple inflammatory hepatic adenomas: an analysis of clinicopathologic and genetic data.

BACKGROUND: Glycogen storage disease (GSD) is a disease caused by excessive deposition of glycogen in tissues due to genetic disorders in glycogen metabolism. Glycogen storage disease type I (GSD-I) is also known as VonGeirk disease and glucose-6-phosphatase deficiency. This disease is inherited in an autosomal recessive manner, and both sexes can be affected. The main symptoms include hypoglycaemia, hepatomegaly, acidosis, hyperlipidaemia, hyperuricaemia, hyperlactataemia, coagulopathy and developmental delay. CASE PRESENTATION: Here, we present the case of a 13-year-old female patient with GSD Ia complicated with multiple inflammatory hepatic adenomas. She presented to the hospital with hepatomegaly, hypoglycaemia, and epistaxis. By clinical manifestations and imaging and laboratory examinations, we suspected that the patient suffered from GSD I. Finally, the diagnosis was confirmed by liver pathology and whole-exome sequencing (WES). WES revealed a synonymous mutation, c.648 G > T (p.L216 = , NM_000151.4), in exon 5 and a frameshift mutation, c.262delG (p.Val88Phefs*14, NM_000151.4), in exon 2 of the G6PC gene. According to the pedigree analysis results of first-generation sequencing, heterozygous mutations of c.648 G > T and c.262delG were obtained from the patient's father and mother. Liver pathology revealed that the solid nodules were hepatocellular hyperplastic lesions, and immunohistochemical (IHC) results revealed positive expression of CD34 (incomplete vascularization), liver fatty acid binding protein (L-FABP) and C-reactive protein (CRP) in nodule hepatocytes and negative expression of ß-catenin and glutamine synthetase (GS). These findings suggest multiple inflammatory hepatocellular adenomas. PAS-stained peripheral hepatocytes that were mostly digested by PAS-D were strongly positive. This patient was finally diagnosed with GSD-Ia complicated with multiple inflammatory hepatic adenomas, briefly treated with nutritional therapy after diagnosis and then underwent living-donor liver allotransplantation. After 14 months of follow-up, the patient recovered well, liver function and blood glucose levels remained normal, and no complications occurred. CONCLUSION: The patient was diagnosed with GSD-Ia combined with multiple inflammatory hepatic adenomas and received liver transplant treatment. For childhood patients who present with hepatomegaly, growth retardation, and laboratory test abnormalities, including hypoglycaemia, hyperuricaemia, and hyperlipidaemia, a diagnosis of GSD should be considered. Gene sequencing and liver pathology play important roles in the diagnosis and typing of GSD.

Primary hyperparathyroidism in pregnancy: a case report highlighting uncommon complication.

Primary hyperparathyroidism (PHPT) is characterized by elevated levels of calcium and parathyroid hormone (PTH). However, the interpretation of diagnostic tests, such as serum calcium and PTH levels, is complex in pregnant women. The aim of this report is to present a case of PHTP in a pregnant adolescent, with a special emphasis on an uncommon complication, as well as diagnostic and treatment strategies. A 17-year-old pregnant female presented with hyperemesis gravidarum and neurological symptoms, leading to the diagnosis of cerebral venous thrombosis. Further investigations revealed hypercalcemia and persistently elevated PTH levels, consistent with PHPT. After localization studies, the patient underwent an emergency parathyroidectomy with a diagnosis of parathyroid adenoma. During follow-up, intrauterine growth restriction and severe preeclampsia developed, necessitating an emergency cesarean section. Both the mother and neonate had favorable outcomes. PHPT is an infrequent condition in the pregnant population, and its diagnosis can be challenging due to the overlap of symptoms with normal physiological changes during pregnancy. The occurrence of uncommon complications, such as thrombotic phenomena, highlights the need for a comprehensive approach to ensure early detection and management. In most cases, parathyroidectomy is the treatment of choice.

El hiperparatiroidismo primario (HPTP) se caracteriza por niveles elevados de calcio y hormona paratiroidea (PTH). Sin embargo, la interpretación de pruebas diagnósticas, como los niveles de calcio sérico y PTH, es compleja en mujeres embarazadas. El objetivo de este reporte es presentar un caso de HPTP en una adolescente embarazada, con especial hincapié en una complicación infrecuente, así como en las estrategias diagnósticas y de tratamiento. Una mujer embarazada de 17 años presentó hiperémesis gravídica y síntomas neurológicos, lo que llevó al diagnóstico de trombosis venosa cerebral. Posteriores investigaciones revelaron hipercalcemia y niveles persistentemente elevados de PTH, consistentes con HPTP. Tras la realización de estudios de localización, la paciente fue sometida a una paratiroidectomía de emergencia con diagnóstico de adenoma de paratiroides. Durante el seguimiento, se desarrolló restricción del crecimiento intrauterino y preeclampsia grave, lo que resultó en la necesidad de realizar una cesárea de emergencia. Tanto la madre como el neonato evolucionaron favorablemente. El HPTP es una condición infrecuente en la población embarazada y su diagnóstico puede ser desafiante por la superposición de síntomas con los cambios fisiológicos normales del embarazo. La aparición de complicaciones infrecuentes, como fenómenos trombóticos, resalta la necesidad de un abordaje integral para garantizar la detección y el manejo temprano. En la mayoría de los casos, la paratiroidectomía es el tratamiento de elección.

Persistent hypercalcaemia associated with two pathogenic variants in the CYP24A1 gene and a parathyroid adenoma-a case report and review.

Introduction: 24-Hydroxylase, encoded by the CYP24A1 gene, is a crucial enzyme involved in the catabolism of vitamin D. Loss-of-function mutations in CYP24A1 result in PTH-independent hypercalcaemia with high levels of 1,25(OH)2D3. The variety of clinical manifestations depends on age, and underlying genetic predisposition mutations can lead to fatal infantile hypercalcaemia among neonates, whereas adult symptoms are usually mild. Aim of the study: We report a rare case of an adult with primary hyperparathyroidism and loss-of-function mutations in the CYP24A1 gene and a review of similar cases. Case presentation: We report the case of a 58-year-old woman diagnosed initially with primary hyperparathyroidism. Preoperatively, the suspected mass adjoining the upper pole of the left lobe of the thyroid gland was found via ultrasonography and confirmed by 99mTc scintigraphy and biopsy as the parathyroid gland. The patient underwent parathyroidectomy (a histopathology report revealed parathyroid adenoma), which led to normocalcaemia. After 10 months, vitamin D supplementation was introduced due to deficiency, and the calcium level remained within the reference range. Two years later, biochemical tests showed recurrence of hypercalcaemia with suppressed parathyroid hormone levels and elevated 1,25(OH)2D3 concentrations. Further investigation excluded the most common causes of PTH-independent hypercalcaemia, such as granulomatous disease, malignancy, and vitamin D intoxication. Subsequently, vitamin D metabolites were measured using LC-MS/MS, which revealed high levels of 25(OH)D3, low levels of 24,25(OH)2D3 and elevated 25(OH)2D3/24,25(OH)2D3 ratios, suggesting a defect in vitamin D catabolism. Molecular analysis of the CYP24A1 gene using the NGS technique revealed two pathogenic variants: p.(Arg396Trp) and p.(Glu143del) (rs114368325 and rs777676129, respectively). Conclusions: The diagnostic process for hypercalcaemia becomes complicated when multiple causes of hypercalcaemia coexist. The measurement of vitamin D metabolites using LC-MS/MS may help to identify carriers of CYP24A1 mutations. Subsequent molecular testing may contribute to establishing the exact frequency of pathogenic variants of the CYP24A1 gene and introducing personalized treatment.

"Micromegaly": Acromegaly with apparently normal GH, an entity on its own?

A small proportion of the patients with acromegaly present with apparently normal basal GH levels and suppressible GH levels despite increased IGF-1 levels, a pattern called micromegaly by some authors. Whether this pattern represents a distinct entity or is just an expression of acromegaly in its early stages is still a matter of debate. Nevertheless, these patients have some peculiar characteristics such as being more likely older and male, mostly harbour microadenomas or small macroadenomas, and have lower IGF-1 and postglucose GH levels. Even though, the frequency and severity of clinical signs and comorbidities are similar to those of patients with classic acromegaly. In conclusion, micromegaly seems to be a distinct clinical entity with a different biological behavior characterized by a low GH output.

Preoperative Lateralization and Diagnostic Value of Selective Bilateral Internal Jugular Venous Sampling in Primary Hyperparathyroidism: Single-Center Experience.

Background and Objectives: Primary hyperparathyroidism (pHPT) is a common endocrine disorder caused by excessive production of parathyroid hormone (PTH) leading to elevated calcium levels. Diagnosis is primarily based on biochemical evaluation, and surgery is the curative treatment. Imaging techniques like ultrasound and Tc-99m Sestamibi scintigraphy are used for localization, but selective Internal Jugular Venous (SVS) becomes valuable in cases of inconclusive or conflicting results. This study evaluated the diagnostic efficacy of SVS for localizing parathyroid adenomas in cases where non-invasive radiological diagnostic methods yielded inconclusive results or negative findings despite clinical symptoms suggestive of pHPT. Materials and Methods: In this retrospective study, a total of 28 patients diagnosed with pHPT underwent SVS at a tertiary center known for receiving referrals from 2017 to 2022. The diagnoses were confirmed through biochemical analysis. The SVS results in 22 patients were compared with non-invasive imaging methods, including ultrasound, scintigraphy, and computed tomography with/without contrast material. SVS was indicated when at least two non-invasive diagnostic procedures failed to clearly localize the parathyroid glands or provided ambiguous results. Results: SVS demonstrated higher sensitivity for localizing parathyroid adenomas compared to non-invasive imaging methods, accurately lateralizing the adenoma in 68.18% of cases. Among the SVS findings, 31.8% of patients had negative results, with 9.1% not having clinically proven parathyroid adenoma, while 22.7% had false negative SVS findings but were later confirmed to have adenoma during surgery. Ultrasound correctly identified the location in 45.45% of cases, CT in 27.27%, and scintigraphy in 40.9%. Conclusions: SVS is a valuable diagnostic tool for accurately localizing parathyroid adenomas in patients with inconclusive non-invasive imaging results. It aids in targeted surgical interventions, contributing to improved management and treatment outcomes in primary hyperparathyroidism.

The improvement of postoperative blood pressure and associated factors in patients with hormone-negative adrenal adenoma and hypertension.

OBJECTIVE: To investigate the effect of adrenal surgery on blood pressure (BP) improvements in patients with hormone-negative adrenal adenoma (HNA) concomitant with hypertension and analyze associated prognostic factors. METHODS: We retrospectively reviewed the clinical data of patients with HNA and hypertension and patients with aldosterone-producing adenoma (APA) and hypertension who underwent adrenal surgery at our center between 2019 and 2022. Hypertension outcomes were evaluated in all patients and subjects were divided into three groups according to follow-up BP and the administration of anti-hypertensive agents: a clinical curation group, an improvement group, and a no-improvement group. Logistic regression analysis was performed to predict factors associated with clinical curation in patients with HNA post-surgery. RESULTS: Of the 182 patients with HNA, clinical curation was achieved in 58 patients (31.9%), improvement in 72 (39.5%), and no improvement in 52 (28.6%). The clinical curation, improvement and no improvement rates in patients with APA were 64.8% (n = 118), 15.9% (n = 29), and 19.2% (n = 35). Multivariate logistic regression analysis indicated that a duration of hypertension ≤6 years and a plasma aldosterone level >160 pg/ml were both independent factors for the clinical curation of hypertension in patients with HNA after adrenal surgery. CONCLUSION: Adrenal surgery can cure or improve hypertension in most patients with HNA, especially in a short duration of hypertension and high plasma levels of aldosterone.

Clinical and Surgical Outcomes of Endoscopic Endonasal Approach for Giant Pituitary Adenomas: Analysis of Predictive Factors.

BACKGROUND: Giant pituitary adenomas (GPAs) are defined as tumors with ≥40 mm in any maximum diameter, and these tend to invade multiple intracranial compartments. Hence, treatment remains a surgical challenge. OBJECTIVE: To describe the clinical and surgical outcomes of the endoscopic endonasal approach (EEA) for GPA in a pituitary referral center in Latin America and to analyze associated predictive factors. METHODS: 37 patients with histologically-confirmed GPA treated solely through the EEA between a 2-year period were included. Preoperative and postoperative clinical and neuroimaging findings; surgical morbidity and mortality; and binary logistic regression analysis to assess predictive factors were analyzed. RESULTS: Preoperative visual impairment prevalence was 97.3%. Mean tumor volume was 32 cc and gross total resection rate was 40.5%. Favorable visual acuity and visual fields outcome rate was 75% and 82.9%, respectively. In the multivariate analysis, bilateral cavernous sinus invasion (P = 0.018) and postoperative cerebrospinal fluid (CSF) leak (P = 0.036) were associated with an unfavorable visual acuity outcome, while radiation therapy (P = 0.035) was for visual fields. Similarly, intraoperative CSF leak was a predictive factor for postoperative CSF leak (10.8%) (P = 0.042) and vascular injury (13.5%) (P = 0.048). CONCLUSIONS: In this first Mexican clinical series, we demonstrated that the EEA is a safe and effective technique for GPA, although early diagnosis and prompt intervention may promote further visual function preservation without significant endocrine morbidity.

[Overcoming therapy resistance in prolactinomas: from perspectives to real clinical practice].

The main treatment option of prolactin-secreting pituitary adenomas is dopamine agonist therapy, which demonstrates prolactin level normalizing and reducing the size of an adenoma in the majority of cases. However, significant amount of patients - about 20% - poorly responds even to high doses of dopamine agonists that is explained by the resistance to therapy. The occurrence of pharmacodynamic characteristics is one of the causes responsible for the development of resistance to typical therapy. Clinical manifestations of persistent hyperprolactinemia are due to following pathological factors: hormonal hypersecretion and the mass-effect of pituitary adenoma. Prevention of irreversible changes is possible only with timely detection of resistance and determination of the optimal personalized treatment algorithm.We report a clinical case of dopamine-agonist resistant microprolactinoma. Patient's health stabilisation, normal level of prolactin and reduction in size of adenoma were achieved due to administration of combined treatment with tamoxifen and dopamine agonists. Hyperprolactinaemia occurring because of prolactin-secreting pituitary adenoma and associated adverse effects are significant problem, decreasing quality of life and demographics in general. This underlines the importance of figuring out causes and identifying predictors of the therapy resistance.The results of the study, illustrated by a clinical example, are presented in the present paper.

Current status of artificial intelligence technologies in pituitary adenoma surgery: a scoping review.

PURPOSE: Pituitary adenoma surgery is a complex procedure due to critical adjacent neurovascular structures, variations in size and extensions of the lesions, and potential hormonal imbalances. The integration of artificial intelligence (AI) and machine learning (ML) has demonstrated considerable potential in assisting neurosurgeons in decision-making, optimizing surgical outcomes, and providing real-time feedback. This scoping review comprehensively summarizes the current status of AI/ML technologies in pituitary adenoma surgery, highlighting their strengths and limitations. METHODS: PubMed, Embase, Web of Science, and Scopus were searched following the PRISMA-ScR guidelines. Studies discussing the use of AI/ML in pituitary adenoma surgery were included. Eligible studies were grouped to analyze the different outcomes of interest of current AI/ML technologies. RESULTS: Among the 2438 identified articles, 44 studies met the inclusion criteria, with a total of seventeen different algorithms utilized across all studies. Studies were divided into two groups based on their input type: clinicopathological and imaging input. The four main outcome variables evaluated in the studies included: outcome (remission, recurrence or progression, gross-total resection, vision improvement, and hormonal recovery), complications (CSF leak, readmission, hyponatremia, and hypopituitarism), cost, and adenoma-related factors (aggressiveness, consistency, and Ki-67 labeling) prediction. Three studies focusing on workflow analysis and real-time navigation were discussed separately. CONCLUSION: AI/ML modeling holds promise for improving pituitary adenoma surgery by enhancing preoperative planning and optimizing surgical strategies. However, addressing challenges such as algorithm selection, performance evaluation, data heterogeneity, and ethics is essential to establish robust and reliable ML models that can revolutionize neurosurgical practice and benefit patients.

The Brunner adenoma of the duodenum with positive fecal occult blood and anemia: A case report.

RATIONALE: Brunner gland adenoma (BGA) is a rare benign duodenal tumor that is an adenomatoid lesion in nature rather than an actual tumor. Patients with different adenoma sizes have various clinical manifestations with nonspecific clinical symptoms. Here, We report a case of BGA with black stool and anemia as the primary manifestations. PATIENT CONCERNS: A young female patient was admitted to the hospital because of black stool and anemia. Endoscopic surgery was performed to a definitive diagnosis, and endoscopic tumor-like lesions were resected. DIAGNOSIS: The patient was diagnosed with duodenal Brunner adenoma and received related treatment. OUTCOMES: After treatment, the patient symptoms improved, and he was discharged. LESSONS: Brunner adenoma of the duodenum is a rare benign duodenum tumor. This report paper describes a case of BGA with black stool and anemia as the primary manifestations, followed by endoscopic resection and treatment. The literature on Brunner adenoma of the duodenum has been analyzed and discussed. Clinicians should pay attention to differentiating the disease based on atypical symptoms.

A case of primary aldosteronism with excessive secretion of renin that was unmasked by kidney transplantation.

A 42-year-old man showed marked hypokalemia after kidney transplantation. He was diagnosed with hypertension and suffered from acute myocardial infarction at 33 and 38 years of age. At 40 years of age, hemodialysis was introduced. A left adrenal tumor was noted and suspected as a non-functional adrenal adenoma at that time. Therefore, he received a living-donor kidney transplant at 42 years of age. After kidney transplantation, the serum creatinine level dropped. His blood pressure remained high, and the serum potassium level decreased. The PRA and PAC were elevated, and ARR was not elevated. Based on the results of various confirmatory tests and vein sampling, he was diagnosed with excessive secretion of renin from the native kidneys that was complicated by primary aldosteronism (PA), and left nephrectomy and adrenalectomy were performed. The overproduction of aldosterone in the resected adrenal adenoma and over secretion of renin in the kidney with arteriolosclerosis were immunohistologically confirmed. After surgery, the PAC decreased, but the PRA did not decrease. The postoperative serum potassium level improved, and the blood pressure was well controlled with a small dose of medication. This is the first reported case of PA with hyperreninemia after kidney transplantation. It should be noted that PA in dialysis patients and kidney transplant recipients may not fulfill the usual diagnostic criteria of an elevated ARR. In such patients, PA should be suspected based on the absolute value of the PAC and responsiveness to ACTH stimulation, and adrenal and renal vein sampling is required for a definitive diagnosis.

Comparisons of risk factors for post-treatment renal dysfunction between the two major subtypes of primary aldosteronism.

OBJECTIVE: Aldosterone-producing adenoma (APA) and bilateral idiopathic hyperaldosteronism (IHA) are the most common subtypes of primary aldosteronism (PA), and the PA subtype dictates the treatment options. This study aimed to identify predictors of declined estimated glomerular filtration rate (eGFR) following each treatment in patients with APA and IHA. METHODS: We retrospectively investigated 45 patients with APA who had undergone adrenalectomy (ADX) and 37 patients with IHA who had received treatment with a mineralocorticoid receptor antagonist (MRA) to identify pre-treatment risk factors for eGFR decline during the post-treatment follow-up period. RESULTS: Patients with APA who underwent ADX exhibited higher eGFR declines than patients with IHA treated with MRA at the 6-month post-treatment evaluation point. A high preoperative plasma aldosterone concentration (PAC) in patients with APA and a high body mass index (BMI) in patients with IHA were identified as independent predictors of higher eGFR decline at 6 months post-treatment (ß=0.42 and ß=0.36, respectively). In patients with APA, the cutoff PAC to best predict a 20% decrease in eGFR following ADX, as determined by receiver operating characteristic analysis, was 524 pg/mL. In patients with IHA, the cutoff BMI to best predict a 10% decrease in eGFR following MRA administration was 25.3 kg/m2. In addition, lower preoperative flow-mediated vasodilation was associated with eGFR decline after ADX in patients with APA. CONCLUSIONS: Greater attention should be given to the above-mentioned risk factors to prevent renal impairment following each treatment in patients with both APA and IHA.

Importance of Intraoperative Factors in Postoperative Arginine Vasopressin Deficiency After Pituitary Adenoma Surgery.

OBJECTIVE: Pituitary adenoma (PA) is the most frequent tumor in the sellar region. Arginine vasopressin deficiency (AVP-D), formerly known as central diabetes insipidus, is a common complication after pituitary surgeries. In this study, we reviewed patients with PAs after endoscopic transsphenoidal surgery, evaluated the incidence of postoperative AVP-D, and determined associated risk factors. METHODS: We retrospectively studied 520 patients who underwent endoscopic transsphenoidal surgery for PAs and evaluated perioperative risk factors and their associations with postoperative AVP-D. Patients who developed AVP-D were categorized in 3 groups: (1) early AVP-D, (2) transient AVP-D, and (3) permanent AVP-D. RESULTS: Of the 520 patients, 24.8% experienced early AVP-D, and 1.9% (n = 10) had transient AVP-D. Permanent AVP-D was observed in only 6 patients (1.1%). Gross total resection, hormonal remission, pituitary stalk manipulation, and intraoperative cerebrospinal fluid leak were significantly associated with a higher incidence of AVP-D (P = .027, P = .002, P < .001 and P < .001, respectively). All patients who developed permanent AVP-D had somatotroph adenomas. AVP-D was not found to be related with tumor size. The length of hospital stay was prolonged by AVP-D on average by 1.5 days (P = .018). CONCLUSION: The reported incidence of AVP-D has a considerably wide range. A consistent definition and grading for AVP-D will increase consistency and comparability among studies. Nonetheless, most patients experience AVP-D on a temporary basis, and only a few require long-term treatment. Cerebrospinal fluid leak, gross total resection, and hormonal remission were identified as risk factors for postoperative AVP-D. We believe that the intraoperative risk factors play the main role in postoperative AVP-D. The course of surgery and operative findings help us plan selective postoperative patient monitoring and care.

Metabolic Syndrome Components in Patients with Pituitary Adenoma.

Pituitary adenomas are benign tumors of the anterior portion of the pituitary gland (adenohypophysis), representing the 25% of all the tumor alterations. Pituitary adenomas are classified by the type of hormone secreted, cellularity, size, and structural alterations by the hormonal segregation. The diagnosis consists on the histopathological identification of cell types and the image-guided by magnetic resonance or tomography; the treatment can be both pharmacological and surgical. Metabolic Syndrome is the set of clinical conditions that increase the risk of cardiovascular diseases with an estimated prevalence of 25% worldwide. The alterations of metabolic syndrome are obesity, hypertension, dyslipidemia, insulin resistance, and diabetes mellitus type II. Pituitary adenomas and metabolic syndrome have an important relationship, hormone-secreting by pituitary adenomas affects a myriad of signaling pathways, which allows a favorable environment for the appearance of the metabolic syndrome. Moreover, patients with pituitary adenomas are shown to have an improvement in metabolic parameters after the medical/surgical treatment. The objective of this review is to explore the possible mechanisms through which PAs contributes to MetSx.

Cardiovascular Risk Markers in Adults With Adrenal Incidentaloma and Mild Autonomous Cortisol Secretion.

CONTEXT: Many adrenal adenomas exhibit mild autonomous cortisol secretion (MACS). Although MACS is associated with increased cardiovascular mortality, the underlying mechanisms are not fully defined. OBJECTIVE: To investigate mechanisms that may link MACS and cardiovascular mortality in adults with adrenal adenoma. DESIGN: Cross-sectional study. PATIENTS: Twenty adults with adrenal adenoma and MACS and 20 controls with nonfunctioning adrenal adenoma. METHODS: Reactive hyperemia index (RHI) was measured by peripheral artery tonometry and 24-hour ambulatory blood pressure monitoring (24h AMBP) was performed. Indices of insulin secretion and sensitivity were estimated by measuring glucose and insulin fasting and following a mixed meal. MAIN OUTCOME MEASURE: The primary outcome was the difference in RHI between participants with MACS vs nonfunctioning adrenal adenoma. RESULTS: The average cortisol after 1-mg dexamethasone and urinary free cortisol were higher in patients with MACS. There was no significant difference in fasting RHI (2.0 [interquartile range (IQR) 1.6-2.4] vs 2.0 [IQR 1.7-2.2, P = .72), but postprandial RHI was higher in patients with MACS (2.2 [1.8-2.7] vs 1.8 [1.5-2.2], P = .04). 24-hour ambulatory blood pressure monitoring and Matsuda index were not significantly different in the groups. Fasting glucose and glucose area under the curve after the mixed meal were higher and insulinogenic index was lower in participants with MACS. CONCLUSION: Adults with adrenal adenoma and MACS do not have fasting endothelial dysfunction and postprandial endothelial function may be better. These patients have fasting and postprandial hyperglycemia with lower insulin secretion, which may underlie the association between MACS and increased cardiovascular mortality.

Approach to the Patient: Reninoma.

A reninoma is a functional tumor of afferent arteriolar juxtaglomerular cells that secretes the enzyme renin, leading to hyperactivation of the renin-angiotensin-aldosterone system. Reninoma is a potentially curable cause of pathological secondary hyperaldosteronism that results in often severe hypertension and hypokalemia. The lack of suppression of plasma renin contrasts sharply with the much more common primary aldosteronism, but diagnosis is often prompted by screening for that condition. The major differential diagnosis of reninoma is renovascular hypertension. Fewer than 200 cases of reninoma have been described. Reninomas have been reported across a broad demographic but have a 2:1 predilection for women, often of childbearing age. Aldosterone receptor blockade, angiotensin-converting enzyme inhibitors, or angiotensin receptor blockers offer effective medical management but are contraindicated in pregnancy, so surgical curative resection is ideal. The current optimal imaging and biochemical workup of reninoma and management approach (ideally, tumor excision with subtotal renal resection) are described.