UNASSIGNED: Juxtaglomerular cell tumor or reninoma is an extremely rare, typically benign, renin-secreting tumor of the kidney that causes secondary hypertension. We describe 99m Tc-MIBI SPECT/CT findings in a case of juxtaglomerular cell tumor. The renal tumor showed isodensity and photopenia on 99m Tc-MIBI SPECT/CT. This case indicates that juxtaglomerular cell tumor can appear cold on 99m Tc-MIBI SPECT/CT, mimicking renal cell carcinoma.

Juxtaglomerular cell tumors (JGCTs) or reninoma are rare kidney tumors leading to secondary hypertension, and the non-specific clinical manifestations bring about challenges to the diagnosis. This study is to summarize the clinical features, laboratory findings, and treatment of JGCTs. The PubMed, EMBASE database, and manual search were utilized to find all cases, and 158 reports containing 261 patients were identified. Data on patients\' demographics, clinical features, diagnostic methods, and treatment options were collected and analyzed. JGCTs occurred predominantly in female patients (female to male ratio, 2.1:1). The median age of patients was 25 years (IQR:18-34 years). Hypertension (97.24%) was the cardinal manifestation. Hypokalemia was reported in 78.71% (159/202) of subjects, and normal serum potassium accounted for 20.79% (42/202). In cases with assessed plasma renin activity (PRA) levels, the median PRA was 7.89 times the upper limit of normal (IQR:3.58-14.41), and 3.82% (5/131) of cases in the normal range. Tumors were detected in 97.8% (175/179) computed tomography (CT), 94.7% (72/76) magnetic resonance imaging (MRI), and 81.5% (110/135) ultrasound, respectively. For 250/261 patients undergoing surgical procedures, 89.14% (197/221), 94.94% (150/158), and 100% (131/131) of patients were restored to normal blood pressure, PRA, and serum potassium, respectively. JGCTs are commonly associated with hypertension, hypokalemia, and hyperreninemia, whereas patients with normotension, normokalemia, and PRA should be systematically pursued after drug-elution lasting for 2 weeks. CT and MRI are more sensitive imaging diagnostic methods. The blood pressure and biochemical parameters of most patients returned to normal after surgery.

肾球旁细胞瘤导致的继发性高血压临床罕见。该文报道1例年轻的女性高血压患者，血肾素水平明显升高，肾脏磁共振显像检查发现肾脏占位，手术切除肾脏肿块，病理检查提示肾球旁细胞瘤。肿瘤切除后，患者血压恢复正常。.

BACKGROUND: Based on existing literature, the juxtaglomerular cell tumor (JGCT) is a rare renal tumor, typically present with hypertension and hypokalemia. Nonfunctioning JGCT, without hypertension or hypokalemia, is extremely rare.
UNASSIGNED: Herein, we report a case of nonfunctioning JGCT mimicking renal cell carcinoma. The 29-year-old woman with an unremarkable past medical history presented with a left renal tumor without hypertension or hypokalemia.
METHODS: Both CT and 18F-FDG-PET/CT suggested a malignancy, possibly renal cell carcinoma.
METHODS: The tumor was then removed completely via robotic assistant laparoscopic partial nephrectomy; and pathology result was JGCT. Since the patient had no hypertension or hypokalemia, a nonfunctional JGCT was diagnosed.
RESULTS: The patient recovered uneventfully, and was in good health in 6-months\' follow-up period.
CONCLUSIONS: Preoperative identification of JGCT is very difficult due to the lack of specific clinical manifestations. This case teaches us that for young patients with renal tumors whose CT enhancement is not obvious at the early phase, JGCT should be considered as a differential diagnosis. Radical nephrectomy should be avoided for JGCT in consideration of its relatively good prognosis.

Juxtaglomerular cell tumor is a rare and benign tumor arising from the juxtaglomerular apparatus that overproduces renin, resulting in secondary hypertension. A 29-year-old woman was incidentally found to have a left renal mass by ultrasonography in a routine health examination. Contrast-enhanced CT results suggested renal cell carcinoma. FDG PET/CT performed for metastatic workup showed increased FDG uptake to the left renal mass and did not reveal any other abnormal FDG-avid lesions. The renal mass was surgically resected and pathological examination confirmed the juxtaglomerular cell tumor of the left kidney.

Bartter syndrome (BS) is a rare autosomal recessive disorder of salt reabsorption at the thick ascending limb of the Henle loop, characterized by hypokalemia, salt loss, metabolic alkalosis, hyperreninemic hyperaldosteronism with normal blood pressure. BS type III, often known as classic BS (CBS), is caused by loss-of-function mutations in CLCNKB (chloride voltage-gated channel Kb) encoding basolateral ClC-Kb.
We reported a 15-year-old CBS patient with a compound heterozygous mutation of CLCNKB gene. She first presented with vomiting, hypokalemic metabolic alkalosis at the age of 4 months, and was clinically diagnosed as CBS. Indomethacin, spironolactone and oral potassium were started from then. During follow-up, the serum electrolyte levels were generally normal, but the patient showed failure to thrive and growth hormone (GH) deficiency was diagnosed. The recombinant human GH therapy was performed, and the growth velocity was improved. When she was 14, severe proteinuria and chronic kidney disease (CKD) were developed. Renal biopsy showed focal segmental glomerulosclerosis (FSGS) with juxtaglomerular apparatus cell hyperplasia, and genetic testing revealed a point deletion of c.1696delG (p. Glu566fs) and a fragment deletion of exon 2-3 deletions in CLCNKB gene. Apart from the CBS, ostium secundum atrial septal defect (ASD) was diagnosed by echocardiography.
This is the first report of this compound heterozygous of CLCNKB gene in BS Children. Our findings contribute to a growing list of CLCNKB mutations associated with CBS. Some recessive mutations can induce CBS in combination with other mutations.

We investigated the significance of the primary cilia on the macula densa and thick ascending limb (TAL) in regulation of renal hemodynamics, sodium excretion, and blood pressure in this study. A tissue-specific primary cilia knock-out (KO) mouse line was generated by crossing NKCC2-Cre mice with IFT88-Δ/flox mice (NKCC2CRE; IFT88Δ/flox), in which the primary cilia were deleted from the macula densa and TAL. NO generation was measured with a fluorescent dye (4,5-diaminofluorescein diacetate) in isolated perfused juxtaglomerular apparatus. Deletion of the cilia reduced NO production by 56% and 42% in the macula densa and TAL, respectively. NO generation by the macula densa was inhibited by both a nonselective and a selective nitric oxide synthesis inhibitors, whereas TAL-produced NO was inhibited by a nonselective and not by a selective NO synthesis 1 inhibitor. The tubuloglomerular feedback response was enhanced in the KO mice both in vitro measured with isolated perfused juxtaglomerular apparatuses and in vivo measured with micropuncture. In response to an acute volume expansion, the KO mice exhibited limited glomerular filtration rate elevation and impaired sodium excretion compared with the wild-type mice. The mean arterial pressure measured with telemetry was the same for wild-type and KO mice fed a normal salt diet. After a high salt diet, the mean arterial pressure increased by 17.4±1.6 mm Hg in the KO mice. On the basis of these findings, we concluded that the primary cilia on the macula densa and TAL play an essential role in the control of sodium excretion and blood pressure.

Juxtaglomerular cell tumor (JGCT) is a rare tumor, with approximately 100 cases reported in the literature. The authors respectively studied the clinical data of 11 patients diagnosed with JGCT in Peking Union Medical College Hospital from 2004 to 2014, and investigated the immunohistochemical profiles in 10 tumors. Nine of the 11 patients were diagnosed before the age of 40 years. Hypertension was present in all patients, while hypokalemia occurred in seven of 11 patients. Computed tomography detected JGCTs with a sensitivity of 100%. Immunoreactivities for CD34 and vascular endothelial growth factor were observed in most tumor specimens, suggesting that JGCTs express a variety of vessel-related immunohistochemical markers, although JGCTs are considered a tumor without abundant blood supply. Nuclear accumulation of cyclin D1 was common in JGCTs. Results from immunohistochemistry were negative for BRAF, HER2, and TFE3, suggesting that BRAF, HER2, and TFE3 genes might not play a part in tumorigenesis in JGCTs.

暂无摘要。

The aim of this study was to improve the diagnostic efficiency for juxtaglomerular cell tumors (JCTs) and to determine whether clinical and magnetic resonance imaging features can help to differentiate JCTs from clear cell renal cell carcinoma (ccRCC). The clinical features of eight patients with JCTs and 27 patients with ccRCCs were analyzed. A flow diagram for young people with hypertension was applied to facilitate the diagnosis. Clinical presentations were analyzed, including age, hypertension, and hypokalemia. The results of our study produced a flow diagram that narrowed the scope of diagnosis. The statistical results demonstrated that patients with a renal mass aged 14 to 30 years, had grade 3 hypertension, or had moderate hypokalemia had a greater possibility of having a JCT than a ccRCC (P<.0000, P<.01, P<.0005, respectively). In addition, the flow diagram and magnetic resonance imaging features were useful to distinguish JCTs from other renal tumors.