Cardiovascular Outcomes of KCNJ5 Mutated Aldosterone-Producing Adenoma: A Systematic Review.

BACKGROUND: While clinical features of KCNJ5-mutated aldosterone-producing adenoma (APA) have been reported, evidence of its clinical outcomes is lacking. We aimed to synthesize available literature about the associations between KCNJ5 mutation with cardiovascular and metabolic outcomes among patients with APA. METHODS: In this systematic review of observational studies, MEDLINE and Embase were searched through August 2022. Two independent authors screened the search results and extracted data from eligible observational studies investigating cardiovascular or metabolic outcomes between KCNJ5-mutated APAs and KCNJ5-non-mutated APAs. Risk of Bias In Non-randomized Studies of Interventions was used to assess the quality of the included studies. RESULTS: A total of 573 titles/abstracts were screened and after the expert opinion of the literature, full text was read in 20 titles/abstracts, of which 12 studies were included. Across 3 studies comparing the baseline or change in the cardiac function between KCNJ5-mutated APAs and KCNJ5-non-mutated APAs, all studies reported the association between impaired cardiac functions and KCNJ5 mutation status. Among 6 studies evaluating the cure of hypertension after surgery, all studies showed that KCNJ5 mutation was significantly associated with the cure of hypertension. In quality assessment, 7 studies were at serious risk of bias, while the remaining studies were at moderate risk of bias. CONCLUSIONS: This systematic review provided evidence of the significant association between KCNJ5 mutation and unfavorable cardiovascular outcomes in patients with primary aldosteronism. Further research is needed to improve the quality of evidence on this topic and elucidate the underlying mechanisms of the potential burden of KCNJ5 mutation.

Adrenal venous sampling criteria for chemiluminescent enzyme immunoassay as a preferable alternative to radioimmunoassay in primary aldosteronism.

Plasma aldosterone concentration (PAC) was routinely measured using radioimmunoassay (RIA); however, the RIA kit was discontinued in March 2021 in Japan. This study examined PAC conversion in adrenal venous sampling (AVS) and AVS criteria when measured using chemiluminescent enzyme immunoassay (CLEIA). PAC of 415 adrenal venous blood samples from AVS (including segmental AVS) of 63 patients with primary aldosteronism was measured using RIA (Spac-S aldosterone kit; Fujirebio Inc.) and CLEIA (Lumipulse Presto Aldosterone; Fujirebio Inc.). PAC of 70 AVS samples was also measured using liquid chromatography-mass spectrometry (LC-MS/MS, ASKA Pharma Medical Co., Ltd.). PAC conversion formulas were determined for each AVS sample assay. PAC measured using CLEIA was significantly correlated with that measured using RIA (correlation coefficient = 0.971). The PAC conversion formula was PAC (CLEIA) = PAC (RIA) × 0.772 - 1,199 pg/mL. The PAC of 14,000 pg/mL in RIA was equivalent to 9,613 pg/mL in CLEIA. PAC measured using CLEIA was also correlated with that measured using LC-MS/MS, and the PAC conversion formula was PAC (CLEIA, pg/mL) = 0.97 × PAC (LC-MS/MS, pg/mL) + 211. The inter-assay coefficient of variability (CV) was 1.1-1.3% and intra-assay CV was 1.0-1.7%, measured using CLEIA. The PAC conversion formula for AVS samples was obtained using CLEIA and RIA, and the conversion formula was different from that for peripheral blood. PAC values measured by CLEIA showed preferable accuracy and high concordance with those measured by LC-MS/MS, even in AVS samples. The study outcomes are useful for interpreting AVS results using non-RIA measurement methods.

Determination of three C18-oxygenated steroids in adrenal lesion segments in primary aldosteronism by super-selective adrenal venous sampling and LC/ESI-MS/MS.

Super-selective adrenal venous sampling (ssAVS) can collect the adrenal tributary venous blood in the aldosterone (ALD)-hypersecreting segments in primary aldosteronism. The concentrations of the C18-oxygenated steroids, especially 18-oxocortisol (18-oxoF), in the lesion segments might be more useful indices than those in the peripheral or adrenal central veins (current candidate indexes) for the differential diagnosis of unilateral ALD-producing adenoma (APA) and bilateral adrenal hyperplasia (BAH). To verify this hypothesis, we developed a liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) method for simultaneously quantifying ALD, 18-oxoF and 18-hydroxycortisol in the adrenal tributary venous serum sample collected by ssAVS (ssAVS serum) and compared their concentrations between APA and BAH patients. Only deproteinization was required for a 10 µl sample prior to the LC/ESI-MS/MS analysis. Endogenous corticoids did not interfere with the quantifications, and the intra-assay and interassay precisions (≤ 8.3%) and accuracies (94.2-102.7%) were acceptable. The clinical study revealed that the 18-oxoF concentration was significantly higher in the ALD-producing tumor tissues (from APA patients) than in the hyperplastic tissues (from BAH patients). However, in conclusion, the 18-oxoF concentration in the ssAVS serum sample can be a rough indication but cannot be decisive for the differential diagnosis between APA and BAH owing to the significant individual difference.

Exploratory study on the relationship between urinary sodium/potassium ratio, salt intake, and the antihypertensive effect of esaxerenone: the ENaK Study.

Excessive salt intake is one of the causes of hypertension, and reducing salt intake is important for managing the risk of hypertension and subsequent cardiovascular events. Esaxerenone, a mineralocorticoid receptor blocker, has the potential to exert an antihypertensive effect in hypertensive patients with excessive salt intake, but evidence is still lacking, especially in clinical settings. We aimed to determine if baseline sodium/potassium ratio and baseline estimated 24-h urinary sodium excretion can predict the antihypertensive effect of esaxerenone in patients with essential hypertension inadequately controlled with an angiotensin receptor blocker (ARB) or a calcium channel blocker (CCB). This was an exploratory, open-label, interventional study with a 4-week observation period and a 12-week treatment period. Esaxerenone was orally administered once daily in accordance with the Japanese package insert. In total, 126 patients met the eligibility criteria and were enrolled (ARB subcohort, 67; CCB subcohort, 59); all were included in the full analysis set (FAS) and safety analysis. In the FAS, morning home systolic blood pressure (SBP)/diastolic blood pressure (DBP) significantly decreased from baseline to end of treatment (primary efficacy endpoint) (-11.9 ± 10.9/ - 6.4 ± 6.8 mmHg, both p < 0.001); a similar trend was observed in both subcohorts. Significant reductions were also shown in bedtime home and office SBP/DBP (all p < 0.001). Each BP change was consistent regardless of the urinary sodium/potassium ratio or estimated 24-h urinary sodium excretion at baseline. The urinary albumin-creatinine ratio (UACR) and N-terminal pro-brain natriuretic peptide (NT-proBNP) significantly decreased from baseline to Week 12 in the total population and both subcohorts. No new safety concerns were raised. Esaxerenone significantly decreased morning home, bedtime home, and office BP; UACR; and NT-proBNP in this patient population, regardless of concomitant ARB or CCB use. The antihypertensive effect of esaxerenone was independent of the urinary sodium/potassium ratio and estimated 24-h urinary sodium excretion at baseline.

Identifying primary aldosteronism patients who require adrenal venous sampling: a multi-center study.

Adrenal venous sampling (AVS) is crucial for subtyping primary aldosteronism (PA) to explore the possibility of curing hypertension. Because AVS availability is limited, efforts have been made to develop strategies to bypass it. However, it has so far proven unsuccessful in applying clinical practice, partly due to heterogeneity and missing values of the cohorts. For this purpose, we retrospectively assessed 210 PA cases from three institutions where segment-selective AVS, which is more accurate and sensitive for detecting PA cases with surgical indications, was available. A machine learning-based classification model featuring a new cross-center domain adaptation capability was developed. The model identified 102 patients with PA who benefited from surgery in the present cohort. A new data imputation technique was used to address cross-center heterogeneity, making a common prediction model applicable across multiple cohorts. Logistic regression demonstrated higher accuracy than Random Forest and Deep Learning [(0.89, 0.86) vs. (0.84, 0.84), (0.82, 0.84) for surgical or medical indications in terms of f-score]. A derived integrated flowchart revealed that 35.2% of PA cases required AVS with 94.1% accuracy. The present model enabled us to reduce the burden of AVS on patients who would benefit the most.

Differences between left adrenal vein sampling sites revealed with segmental sampling in primary aldosteronism.

OBJECTIVES: To clarify the differences between two left sampling sites (left adrenal central vein [LCV] and common trunk [CMT], conjunction with LCV and inferior phrenic vein) and their impact on adrenal venous sampling (AVS) in primary aldosteronism by analyzing the results of segmental AVS (sAVS). METHODS: We retrospectively analyzed a final cohort of 432 patients who underwent cosyntropin-stimulated sAVS from 2017 to 2020. Hormone levels in the LCV and the CMT were compared. Subtype diagnosis was based on the lateralization index with LCV and CMT sampling (a cutoff value of 4) and sAVS after excluding patients with a selectivity index (SI) <3. RESULTS: Compared with the LCV, CMT sampling showed significantly lower aldosterone and cortisol levels and a higher proportion of cases with an SI of <3 (2.8% vs 0.5%, p = 0.025) and <5 (6.9% vs 0.5%, p < 0.001), while the aldosterone-to-cortisol ratio and the lateralization index were not significantly different. Subtyping of both sites was concordant in 94.7% (393/415) and discordant in the remainder, which included left and right aldosterone-producing adenoma and idiopathic hyperaldosteronism cases referring to the sAVS. There was no significant difference between the concordance rate of the two sampling sites based on the sAVS diagnosis. CONCLUSIONS: LCV sampling meets the SI criteria for successful AVS more frequently compared with CMT sampling, but neither was better than the other in terms of diagnosis under conditions of meeting the criteria. ADVANCES IN KNOWLEDGE: LCV sampling would decrease the number of cases judged as AVS failure.

Association of Reversal of Renin Suppression With Long-Term Renal Outcome in Medically Treated Primary Aldosteronism.

BACKGROUND: Renin suppression in primary aldosteronism indicates mineralocorticoid receptor activation via excessive aldosterone secretion, inducing renal damage. We investigated whether the reversal of renin suppression after the initiation of mineralocorticoid receptor antagonist therapy was associated with long-term renal outcomes in medically treated patients with primary aldosteronism. METHODS: This retrospective cohort study included 318 patients with primary aldosteronism treated with mineralocorticoid receptor antagonist between 2008 and 2020 at the Yokohama Rosai Hospital in Japan. The posttreatment renin status was defined as unsuppressed (ie, reversal of renin suppression) when individual plasma renin activity after the initiation of mineralocorticoid receptor antagonist (post-plasma renin activity) was ≥1.0 ng/mL per hour; otherwise, it was defined as suppressed. We analyzed the association of posttreatment renin status with subsequent longitudinal estimated glomerular filtration rate changes using linear mixed-effects models for repeated measurements, adjusting for potential confounders. RESULTS: The posttreatment renin status of 119 patients was unsuppressed (median post-plasma renin activity, 1.7 ng/mL per hour) and that of 199 patients was suppressed (median post-PRA, 0.5 ng/mL per hour). Through the median follow-up period of 3.1 years, the decline in estimated glomerular filtration rate was milder among patients with the unsuppressed posttreatment renin (-0.46 [95% CI, -0.63 to -0.28] mL/min per 1.73 m2 per year) than those with suppressed posttreatment renin (-1.41 [95% CI, -1.56 to -1.27] mL/min per 1.73 m2 per year; difference, 0.96 [95% CI, 0.72-1.20] mL/min per 1.73 m2 per year). CONCLUSIONS: Our findings may highlight the importance of reversing renin suppression with optimal mineralocorticoid receptor antagonist titration in medically treated primary aldosteronism, which could mitigate adverse renal outcomes.

Feasibility of single-port laparoscopic partial adrenalectomy with selective adrenal venous sampling and high-resolution ultrasound for unilateral aldosterone-producing adenomas.

BACKGROUND: The surgical and endocrinological outcomes of single-port laparoscopic partial adrenalectomy for patients with aldosterone-producing adenomas are unknown. Precise diagnosis of intra-adrenal aldosterone activity and a precise surgical procedure may improve outcomes. In this study, we aimed to determine the surgical and endocrinological outcomes of single-port laparoscopic partial adrenalectomy with preoperative segmental selective adrenal venous sampling and intraoperative high-resolution laparoscopic ultrasound in patients with unilateral aldosterone-producing adenomas. We identified 53 patients with partial adrenalectomy and 29 patients with laparoscopic total adrenalectomy. Single-port surgery was performed for 37 and 19 patients, respectively. METHODS: A single-center, retrospective cohort study. All patients with unilateral aldosterone-producing adenomas diagnosed by selective adrenal venous sampling and treated surgically between January 2012 and February 2015 were included. Follow-up with biochemical and clinical assessments was set at 1 year after surgery for short-term outcomes and was performed every 3 months after surgery. RESULTS: We identified 53 patients with partial adrenalectomy and 29 patients with laparoscopic total adrenalectomy. Single-port surgery was performed for 37 and 19 patients, respectively. Single-port surgery was associated with shorter operative and laparoscopic times (odds ratio, 0.14; 95% confidence interval, 0.039-0.49; P = .002 and odds ratio, 0.13; 95% confidence interval, 0.032-0.57; P = .006, respectively). All single-port and multi-port partial adrenalectomy cases showed complete short-term (median 1 year) biochemical success, and 92.9% (26 of 28 patients) who underwent single-port partial adrenalectomy and 100% (13 of 13 patients) who underwent multi-port partial adrenalectomy showed complete long-term (median 5.5 years) biochemical success. No complications were observed with single-port adrenalectomy. CONCLUSION: Single-port partial adrenalectomy is feasible after selective adrenal venous sampling for unilateral aldosterone-producing adenomas, with shorter operative and laparoscopic times and a high rate of complete biochemical success.

The utility of zebrafish cardiac arrhythmia model to predict the pathogenicity of KCNQ1 variants.

Genetic testing for inherited arrhythmias and discriminating pathogenic or benign variants from variants of unknown significance (VUS) is essential for gene-based medicine. KCNQ1 is a causative gene of type 1 long QT syndrome (LQTS), and approximately 30% of the variants found in type 1 LQTS are classified as VUS. We studied the role of zebrafish cardiac arrhythmia model in determining the clinical significance of KCNQ1 variants. We generated homozygous kcnq1 deletion zebrafish (kcnq1del/del) using the CRISPR/Cas9 and expressed human Kv7.1/MinK channels in kcnq1del/del embryos. We dissected the hearts from the thorax at 48 h post-fertilization and measured the transmembrane potential of the ventricle in the zebrafish heart. Action potential duration was calculated as the time interval between peak maximum upstroke velocity and 90% repolarization (APD90). The APD90 of kcnq1del/del embryos was 280 ± 47 ms, which was significantly shortened by injecting KCNQ1 wild-type (WT) cRNA and KCNE1 cRNA (168 ± 26 ms, P < 0.01 vs. kcnq1del/del). A study of two pathogenic variants (S277L and T587M) and one VUS (R451Q) associated with clinically definite LQTS showed that the APD90 of kcnq1del/del embryos with these mutant Kv7.1/MinK channels was significantly longer than that of Kv7.1 WT/MinK channels. Given the functional results of the zebrafish model, R451Q could be reevaluated physiologically from VUS to likely pathogenic. In conclusion, functional analysis using in vivo zebrafish cardiac arrhythmia model can be useful for determining the pathogenicity of loss-of-function variants in patients with LQTS.

Node-by-node diagnosis for multiple ipsilateral nodules by segmental adrenal venous sampling in primary aldosteronism.

OBJECTIVES: In patients with primary aldosteronism (PA), multiple adrenocortical nodules may be present on the surgical side. The aim of this study was to clarify the pathological diagnosis and the node-by-node diagnostic capability of segmental adrenal venous sampling (sAVS). DESIGN: Retrospective study. PATIENTS: A total of 162 patients who underwent adrenalectomy following sAVS were studied. MEASUREMENTS: Multiple nodules on the surgical side were extracted while referring to contrast-enhanced computed tomography images. We also performed a detailed histopathological analysis of the resected specimens from patients undergoing sAVS, which included immunohistochemistry for CYP11B2. RESULTS: In 11 (6.8%) patients, two to three nodules were detected on the surgical side. All patients were diagnosed by sAVS with at least one aldosterone-producing adenoma (APA) for localized aldosterone elevation in tributaries. Seven patients showed a lateralization index value of ≥4 after ACTH stimulation. Histopathologically and clinically, two patients had two or three CYP11B2-positive APAs, and the other nine patients both APAs and non-APAs. The positive predictive value of the most suspected APA, that is, the drainer that showed the highest aldosterone level by sAVS, was 11/11 (100%, 95% confidence interval [CI]: 71.5%-100%), while that for the second and third suspected APA was 3/7 (42.9%, 95% CI: 9.9%-81.6%), and they were significantly different (p = .01). Further, the positive predictive value of non-APA was 4/4 (100%, 95% CI: 39.8%-100%). CONCLUSIONS: The sAVS could correctly diagnose the aldosterone production in multiple ipsilateral adrenal nodules.

Association Between Aldosterone and Hypertension Among Patients With Overt and Subclinical Hypercortisolism.

Introduction: Hypertension is one of the most common clinical features of patients with overt and subclinical hypercortisolism. Although previous studies have shown the coexistence of autonomous cortisol and aldosterone secretion, it is unclear whether aldosterone plays a role in hypertension among patients with hypercortisolism. Therefore, we examined the associations of plasma aldosterone concentrations (PACs) with hypertension among patients with overt and subclinical hypercortisolism. Methods: This single-center retrospective cohort study included patients with adrenal tumor and serum cortisol levels after 1-mg dexamethasone suppression test >1.8 µg/dL (50 nmol/L). Using multivariable regression models adjusting for baseline characteristics, we investigated the association of PACs with systolic blood pressure and postoperative improvement of hypertension after the adrenalectomy. Results: Among 89 patients enrolled in this study (median age, 51 years), 21 showed clinical signs of Cushing syndrome (overt hypercortisolism) and 68 did not show clinical presentations (subclinical hypercortisolism). We found that higher PACs were significantly associated with elevated systolic blood pressure among patients with subclinical hypercortisolism (adjusted difference [95% CI] = +0.59 [0.19-0.99], P = 0.008) but not among those with overt hypercortisolism. Among 33 patients with subclinical hypercortisolism and hypertension who underwent adrenalectomy, the postoperative improvement of hypertension was significantly associated with higher PACs at baseline (adjusted risk difference [95% CI] = +1.45% [0.35-2.55], P = 0.01). Conclusion: These findings indicate that aldosterone may contribute to hypertension among patients with subclinical hypercortisolism. Further multi-institutional and population-based studies are required to validate our findings and examine the clinical effectiveness of the intervention targeting aldosterone for such patients.

Mixed corticomedullary tumor of the adrenal gland.

Mixed corticomedullary tumor (MCMT) of the adrenal gland is an extremely rare tumor characterized by an admixture of steroidogenic cells and chromaffin cells in a single tumor mass simultaneously producing adrenocortical hormones and catecholamines; it is associated with ectopic adrenocorticotropic hormone (ACTH) in some cases. We reviewed and summarized clinicopathological data of 28 MCMTs, including four metastatic tumors in 26 previous reports. These reports included 21 females and 7 males, and the average tumor sizes were 4.8 ± 2.5 cm and 12.6 ± 6.4 cm in the non-metastatic and metastatic groups, respectively (P<0.001). The clinical manifestations and laboratory data were as follows: Cushing or subclinical Cushing syndrome, 58% (14/24); hypertension, 71% (17/24); elevated adrenocortical hormones, 75% (18/24); elevated catecholamines, 75% (18/24); and ectopic ACTH, 71% (10/14). All four patients with metastatic MCMTs had poor prognoses and elevated adrenocortical hormone levels; however, only two patients had elevated catecholamine levels. Immunohistochemistry was essential for the pathologic diagnosis of MCMTs. In this study, using an improved technique, we detected ectopic ACTH-producing cells in the same paraffin-embedded sections reported to be negative in our previous reports. As MCMT is composed of cells with embryologically different origins, its pathogenesis has been explained by various hypotheses. We compared MCMT to the adrenal gland of birds and the early stage of human fetuses, in which nests of chromaffin cells and steroidogenic cells admix without the formation of cortex and medulla. MCMT is characterized by the immaturity of organogenesis and might be classified as an adrenal embryonal tumor.

Aldosterone-Producing Adenomas of Increased Size Are Associated With Higher Steroidogenic Activity.

CONTEXT: There are inconsistent results and insufficient evidence as to whether an association exists between the size and aldosterone-producing ability of aldosterone-producing adenomas. OBJECTIVE: We further investigated this possible association retrospectively. METHODS: A total of 142 cases of primary aldosteronism diagnosed as unilateral by adrenal venous sampling at 2 referral centers between 2009 and 2019 were included. We classified these individuals into small and large tumor groups using a diameter of 14 mm as a cutoff. This size was the median diameter of the tumor on the affected side of the adrenal gland. We compared plasma aldosterone concentration (PAC), plasma renin activity (PRA), PAC to PRA ratio, PAC from a saline infusion test (SIT), urinary aldosterone secretion (uAld), and serum potassium as indices of aldosterone-producing ability between the 2 groups. In some cases, we conducted histopathological evaluations and detection of the KCNJ5 mutation. RESULTS: PAC, PAC to PRA ratio, PAC from SIT, and uAld were higher and serum potassium was lower in the large tumor group. PAC, PAC from SIT, uAld, and serum potassium significantly correlated with tumor diameter. PRA was not associated with tumor diameter. Clear cell-dominant cases were more common in the large tumor group, while cases showing a strong expression of CYP11B2 were not significantly different between the groups. KCNJ5 mutations tended to be more common in the large tumor group. CONCLUSION: The higher aldosterone-producing ability in larger adenomas can be used to infer the responsible lesion and disease type.

Safety and feasibility of radiofrequency ablation using bipolar electrodes for aldosterone-producing adenoma: a multicentric prospective clinical study.

Evaluation of feasibility and safety of percutaneous radiofrequency ablation using bipolar radiofrequency devices in a prospective multicenter cohort of patients with benign aldosterone-producing adenoma. A total of five institutions participated. CT-guided percutaneous RFA was performed for patients diagnosed as APA. The safety of the procedure was evaluated using the Common Terminology Criteria for Adverse Events. During the 84-day follow-up period, serial changes in plasma aldosterone concentration and plasma renin activity were measured. The percentage of patients with normalized hormonal activity after the procedure, was calculated with 95% confidence intervals. Forty patients were enrolled, and two patients were excluded for cerebral hemorrhage and no safe puncture root. In another patients, RFA was tried, but an intraprocedural intercostal arterial injury occurred. Consequently, RFA was completed in thirty-seven patients (20 men, 17 women; mean age, 50.4 ± 10.0 year). The tumor size was 14.8 ± 3.8 mm. The treatment success rate of the ablation was 94.6% (35/37), and a 2nd session was performed in 2.7% (1/37) patients. Grade 4 adverse events were observed in 4 out of 38 sessions (10.5%). The normalization of plasma aldosterone concentration or aldosterone-renin ratio was 86.5% (72.0-94.1: 95% confidence interval) on day 84. Percutaneous CT-guided RFA for APA using a bipolar radiofrequency system was safe and feasible with clinical success rate of 86.5% on day 84.

Clinical Translationality of KCNJ5 Mutation in Aldosterone Producing Adenoma.

Hypertension due to primary aldosteronism poses a risk of severe cardiovascular complications compared to essential hypertension. The discovery of the KCNJ5 somatic mutation in aldosteroene producing adenoma (APA) in 2011 and the development of specific CYP11B2 antibodies in 2012 have greatly advanced our understanding of the pathophysiology of primary aldosteronism. In particular, the presence of CYP11B2-positive aldosterone-producing micronodules (APMs) in the adrenal glands of normotensive individuals and the presence of renin-independent aldosterone excess in normotensive subjects demonstrated the continuum of the pathogenesis of PA. Furthermore, among the aldosterone driver mutations which incur excessive aldosterone secretion, KCNJ5 was a major somatic mutation in APA, while CACNA1D is a leading somatic mutation in APMs and idiopathic hyperaldosteronism (IHA), suggesting a distinctive pathogenesis between APA and IHA. Although the functional detail of APMs has not been still uncovered, its impact on the pathogenesis of PA is gradually being revealed. In this review, we summarize the integrated findings regarding APA, APM or diffuse hyperplasia defined by novel CYP11B2, and aldosterone driver mutations. Following this, we discuss the clinical implications of KCNJ5 mutations to support better cardiovascular outcomes of primary aldosteronism.

The Proportion of Long-term Response to Anti-N IgG Antibody after 12 Months for COVID-19 Subclinical Infections and a Longitudinal Survey for COVID-19 Subclinical Infections in 2021.

Objective To examine the continuation of antibody prevalence status after 12 months and background factors in antibody-positive subjects following asymptomatic infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods We initially determined the SARS-CoV-2 anti-nucleocapsid protein immunoglobulin G (anti-N IgG) antibody prevalence in 1,603 patients, doctors, and nurses at 65 medical institutions in Kanagawa Prefecture, Japan. We then obtained consent from 33 of the 39 subjects who tested positive and performed follow-up for 12 months. Results Follow-up for up to 12 months showed that a long-term response of the anti-N IgG antibody could be detected in 6 of the 33 participants (18.2%). The proportions with hypertension, using an angiotensin-receptor blocker, and without a drinking habit were higher among the participants with a long-term anti-N IgG antibody response for up to 12 months than among those without a long-term antibody response. Conclusions The proportion of individuals with subclinical COVID-19 who continuously had a positive result for the anti-N IgG antibody at 12 months was low.

A Case of 123I-Metaiodobenzylguanidine Scintigraphy-Negative Pheochromocytoma with a Tumor-Developing Mutation in the RET Gene.

Pheochromocytoma (PCC) is rare catecholamine-producing endocrine tumor that metastasizes in approximately 10% of cases. As a functional imaging of PCC, 123I-metaiodobenzylguanidine (MIBG) scintigraphy was established, and some cases of PCC exhibit negative accumulation on MIBG scintigraphy, indicating a high risk of metastasis. Additionally, germline genetic variants of PCC are evident in approximately 30% of cases, although the genotype-phenotype correlation in PCC, especially the association between genetic mutations and MIBG scintigraphy, remains unclear. A 33-year-old man was admitted to our hospital for further examination for hypertension. He was diagnosed with sporadic PCC, and left adrenalectomy was performed. The adrenal tumor was negative on MIBG scintigraphy. Histology of the tumor revealed a moderately differentiated PCC. Target gene testing revealed a mutation in RET (c.2071G > A). This mutation has been reported to be a tumor-developing gene involved in the pathogenesis of PCC. Moreover, the RET mutation is the only gene mutation reported in a previous study of PCC with negative results on MIBG scintigraphy, except for the SDHB gene mutation, which is a common mutation in metastatic PCC. Correctively, the present RET gene mutation may be associated to MIBG-scintigraphy negative PCC and its pathophysiology. Clinicians should follow such cases more cautiously in clinical practice.