Intra-operative parathyroid hormone evaluation is superior to frozen section analysis in parathyroid surgery.

BACKGROUND: Surgery is currently the only treatment option for patients with primary hyperparathyroidism (PHPT). Recently, minimally invasive parathyroidectomy (MIP) has begun to replace traditional bilateral neck exploration (BNE). OBJECTIVE: The aim of this study is to compare the results of parathyroidectomies performed in our hospital over the past decade that were guided by intra-operative parathyroid hormone (IOPTH) sampling or frozen section (FS) analysis. MATERIAL AND METHODS: Data on 697 patients who underwent parathyroidectomies in the Department of Endocrine Surgery, Dokuz Eylul University between January 2005 and 2018 were included in this study. Patients with malignancies other than thyroid papillary microcarcinoma and parathyroid cancer were excluded from the study. RESULTS: The concomitant use of neck ultrasound (US) and technetium 99m Sestamibi (99mTc MIBI) scintigraphy successfully localized the hyperfunctioning parathyroid glands in nearly 96% of cases. As compared with the IOPTH group, the operation time was longer in the FS group (p < 0.001), and the need for postoperative calcium (Ca) supplementation was higher (p < 0.001). The duration of hospitalization (days) was significantly higher in the FS group (4.2 ± 3.4 vs. 2.6 ± 1.9) as compared with that in the IOPTH group (p < 0.001). In addition, the recurrence rate in the FS group was significantly higher than that in the IPOTH group (p = 0.002). CONCLUSION: IOPTH sampling is a safe and effective method when performed by experienced surgeons and with appropriate preoperative screening. This study emphasizes that IOPTH sampling. We believe that the success in parathyroid surgery is due to three factors: correct indication, accurate localization and experienced surgeon.

Anesthetic considerations in hyperparathyroid crisis: A case report.

INTRODUCTION: Hyperparathyroid crisis is a rare and potentially life-threatening complication of severe calcium intoxication. Parathyroidectomy is the only curative method for hyperparathyroid crisis. Several case reports and case series have been published on the medical and surgical treatments for hyperparathyroid crisis, however, few reports have focused on the associated perioperative anesthetic management. PATIENT CONCERNS: A 48-year-old Chinese woman presented with a 2-week history of nausea and vomiting and complained of mental status alteration including confusion and agitation in the 24 hours prior to her admission. She denied any history of past illness. Laboratory tests showed severe hypercalcemia crisis with a serum calcium level of 5.21 mmol/L and a serum intact parathyroid hormone level of > 5000 pg/mL. DIAGNOSIS: The diagnosis was hyperparathyroid crisis, acute kidney injury, acute liver injury, rhabdomyolysis, infection, and shock. INTERVENTIONS: She underwent initial management with aggressive intravenous fluid resuscitation, loop diuretic treatment, vitamin D supplement, intravenous bisphosphonates, and calcitonin therapy. However, her condition worsened, and she was transferred to the operating theater for a parathyroidectomy under general anesthesia. She was under general anesthesia and monitored with electrocardiogram, pulse oxygen saturation, continuous arterial blood pressure, central venous pressure and nasopharyngeal temperature. Cardiac output and stroke volume variation were monitored from the FloTrac system. After liberal fluid rehydration, circulatory support, cooling treatment and calcium supplement after tumor removal, her unstable vital signs gradually improved. OUTCOMES: After meticulous anesthetic management by the anesthesiologist and complete tumor resection by the surgeon, she survived this fatal disease. The patients was discharged on postoperative day 37 without any sequelae. LESSONS: Patients with hyperparathyroid crisis should undergo a thorough preoperative evaluation. Difficult airway, fluid depletion, multiple organ dysfunction, hypercoagulability, and concomitant diseases are the primary challenges in anesthetic management. After tumor removal, the serum calcium level should be monitored closely and calcium should be supplemented in a timely manner to prevent serious complications.

Effect of Parathyroidectomy Timing in Kidney Transplant Recipients on Graft Function.

OBJECTIVES: Persistent hyperparathyroidism can have a deleterious effect on graft function in kidney transplant recipients, although serum calcium, phosphorus, and parathyroid hormone levels tend to normalize after successful transplant. Parathyroidectomy can result in sustained amelioration of persistent hyperparathyroidism despite graft failure risk and unfavorable graft outcomes. Data on this issue are limited and conflicting. Here, we evaluated the effects of parathyroidectomy on graft function in kidney transplant recipients. MATERIALS AND METHODS: This retrospective study included 249 adult kidney transplant recipients (121 deceased-donor/128 living-donor; 142 males/107 females; mean age of 39.3 ± 11.6 y; mean follow-up of 46.5 ± 23.5 mo). Participants were grouped as those without (n = 222), those with pretransplant (n = 12), and those with posttransplant (n = 15) parathyroidectomy. Graft outcomes and serum calcium, phosphorus, and parathyroid hormone levels were studied. RESULTS: Serum calcium levels at baseline and at 1, 3, 6, and 12 months and parathyroid hormone levels at baseline and at 6 and 12 months were higher and serum phosphorus levels at 3, 6, and 12 months were lower in the posttransplant parathyroidectomy group versus the other groups (P < .001). We observed no significant differences between groups regarding serum calcium, phosphorus, and parathyroid hormone levels at last visit. Estimated glomerular filtration rates at 3, 6, and 12 months and at last visit in the pretransplant parathyroidectomy group were higher than in those without parathyroidectomy (P < .05) and higher at 6 and 12 months than in the posttransplant parathyroidectomy group (P < .05). No significant differences regarding graft loss and patient mortality were observed among the 3 groups (P > .05). CONCLUSIONS: Parathyroidectomy resulted in sustained decreased levels of serum calcium and parathyroid hormone. We observed no graft failure risk associated with parathyroidectomy in our study. Parathyroidectomy before transplant is advantageous with better graft function.

Microsatellite instability driven metastatic parathyroid carcinoma managed with the anti-PD1 immunotherapy, pembrolizumab.

The present case report describes a 65-year-old man with Lynch syndrome and hypercalcaemia associated with hyperparathyroidism. Parathyroid surgery confirmed the diagnosis of parathyroid carcinoma. Serum calcium and parathyroid hormone (PTH) concentrations serially increased after initial surgery. Imaging study and subsequent biopsy confirmed lung metastases with mismatch repair deficiency. Pembrolizumab was initiated achieving 60% reduction in tumour burden.

Secondary and Tertiary Hyperparathyroidism: A Narrative Review.

End-stage renal disease is often complicated by the occurrence of secondary and eventually tertiary hyperparathyroidism, characterized by increased parathormone, calcium, and phosphate concentrations. Related symptoms include pruritus and osteodynia, concentration difficulties, and feelings of depression may be present. In the long-term, end-stage renal disease patients with hyperparathyroidism have an increased risk of all-cause and cardiovascular mortality. Among treatment options are vitamin D supplements, phosphate binders, calcimimetics, and surgical parathyroidectomy. Determining the optimal treatment for the individual patient is challenging for nephrologists and endocrine surgeons. This review resumes the pathogenesis of hyperparathyroidism, clinical presentation, required diagnostic work-up, and discusses indications for the available treatment options for patients with secondary and tertiary hyperparathyroidism.

Parathyroid Diseases.

Although uncommon in pregnancy, parathyroid dysfunction may produce significant perinatal and maternal morbidity and mortality. The prevalence of hyperparathyroidism is 0.5%. The most common cause of primary hyperparathyroidism in pregnancy is a single parathyroid adenoma, which is present in nearly 80% of cases. Surgery is the only definitive treatment for primary hyperparathyroidism, with a cure rate that is excellent. The most common etiology of hypoparathyroidism is damage to the parathyroid glands after surgery, with an incidence of 0.2%. Treatment of hypoparathyroidism is usually a high-calcium diet with vitamin D supplementation. Vitamin D deficiency is common, associated with perinatal morbidity and easily corrected.

Unusual case of chronic recurrent multifocal osteomyelitis.

BACKGROUND: Chronic recurrent multifocal osteomyelitis (CRMO) is a rare auto-inflammatory bone disorder that primarily affects young girls, with a mean age of 10 years at onset. Generally, it is a self-limited disease. However, recent data indicate that more than 50% of patients have a chronic persistent disease and about 20% a recurring course of this condition. Also, there are more cases reported with associated auto-inflammatory and autoimmune diseases. In this case report, we present a rare case of sporadic CRMO in which the patient eventually developed C-ANCA (cytoplasmic anti-neutrophil cytoplasmic antibodies)-associated renal vasculitis and hyperparathyroidism. CASE PRESENTATION: A 14 year old female patient was brought to the emergency department with a sudden onset of left leg pain and oedema. After physical evaluation and initial investigation, she was diagnosed with femoral and pelvic deep vein thrombosis. While searching for possible thrombosis causes, osteomyelitis of the left leg was identified. Additional CT and MRI scans hinted at the CRMO diagnosis. Due to the multifocal lesions of CRMO, endocrinological evaluation of calcium metabolism was done. The results showed signs of hyperparathyroidism with severe hypocalcaemia. Moreover, when kidney damage occurred and progressed, a kidney biopsy was performed, revealing a C-ANCA associated renal vasculitis. Treatment was started with cyclophosphamide and prednisolone according to the renal vasculitis management protocol. Severe metabolic disturbances and hyperparathyroidism were treated with alfacalcidol, calcium and magnesium supplements. Secondary glomerulonephritis (GN) associated hypertension was treated with ACE (angiotenzine converting enzyme) inhibitors. Anticoagulants were prescribed for deep vein thrombosis. After 1.5 years of treatment, the patient is free of complaints. All microelement and parathormone levels are within normal range. Kidney function is now normal. To date, there are no clinical or diagnostic signs of deep vein thrombosis. CONCLUSIONS: This case report presents a complex immunodysregulatory disorder with both auto-inflammatory and autoimmune processes. We hypothesize that the long lasting active inflammation of CRMO may induce an autoimmune response and result in concomitant diseases like C-ANCA-associated vasculitis in our patient. Any potential specific pathogenic relationships between these two rare pathologies may need to be further studied. Furthermore, there is a lack of specific biomarkers for CRMO and more studies are necessary to identify CRMO's characteristic patterns and how to best monitor disease progression.

Vitamin D (25(OH)D) in patients with chronic kidney disease stages 2-5.

OBJECTIVE: To establish the impact the chronic kidney disease stage has in the native vitamin D levels in patients not undergoing dialysis treatment. METHODS: A study performed in Manizales, Colombia, a city located 2,200 meters above sea level, without important stational variations. Patients with 18 years of age or more, with chronic kidney disease stages 2 to 5 and not undergoing dialysis treatment were recruited for this study. Demographic and anthropometric variations were evaluated as well as solar exposure, CKD etiology and laboratory variables related to bone and mineral diseases. For each CKD clinical stage, correlations were evaluated for vitamin D levels, laboratory results for bone and mineral diseases, solar exposure and ethnicity. RESULTS: Three hundred thirty-three patients were evaluated with a median age of 71 years, most of them mestizo (71%), 173 were women. The main CKD etiology was hypertensive nephropathy (32.2%). 21.1% of patients had normal vitamin D levels, 70.1% were within insufficient range and 8.8% were in deficit. A negative correlation was found between the levels of vitamin 25 (OH) D and the values for: creatinine, phosphorous, calcium x phosphorous product, PTH, 24 hours urine protein and BMI. A positive relationship was found for calcium and albumin. Positive significant statistical correlation was found for vitamin 25(OH) D levels and solar exposure for stages 3b and 4 of CKD. CONCLUSIONS: It is common to find low levels of vitamin 25(OH) D in patients with CKD; these can contribute to the appearance of secondary hyperparathyroidism. OBJETIVO: Establecer el impacto del estadio clínico en los niveles de vitamina D nativa en pacientes con enfermedad renal crónica (ERC) sin diálisis. MÉTODOS: Estudio realizado en Manizales, Colombia, una ciudad tropical ubicada a 2,200 metros de altura sobre el nivel del mar, sin variaciones estacionales importantes a lo largo del año. Se incluyeron pacientes mayores de 18 años, con enfermedad renal crónica estadio 2 a 5 sin tratamiento dialítico. En ellos se evaluaron variables demográficas, antropométricas, grado de exposición solar, etiología de la enfermedad, y variables de laboratorio relacionadas con desórdenes óseos y minerales. Para cada estadío clínico se evaluó la correlación entre los niveles de vitamina D y los resultados de las pruebas de laboratorio relacionadas con desordenes óseos y minerales, exposición solar y etnia. RESULTADOS: Se evaluaron 331 pacientes, con una edad media de 71 años, la mayoría mestizos (71%), 173 mujeres. La principal etiología de ERC fue nefropatía hipertensiva (33.2%). El 21.1% de los pacientes tenían niveles normales de vitamina D, fueron insuficientes en 70.1% y 8.8% en déficit. Se detectó correlación negativa, entre los niveles de vitamina 25(OH)D y los valores de creatinina, fósforo, producto calcio x fósforo, PTH, proteínas en orina de 24 horas e IMC. Correlación positiva para el calcio y la albumina. Se encontró significancia estadística positiva entre los niveles de vitamina 25(OH)D y la exposición solar para los estadios 3b y 4. CONCLUSIONES: En pacientes con ERC es comun detectar bajos niveles de 25(OH)D, los cuales pueden contribuir a la generación de hiperparatiroidismo secundario.

The American Association of Endocrine Surgeons Guidelines for Definitive Management of Primary Hyperparathyroidism.

Importance: Primary hyperparathyroidism (pHPT) is a common clinical problem for which the only definitive management is surgery. Surgical management has evolved considerably during the last several decades. Objective: To develop evidence-based guidelines to enhance the appropriate, safe, and effective practice of parathyroidectomy. Evidence Review: A multidisciplinary panel used PubMed to review the medical literature from January 1, 1985, to July 1, 2015. Levels of evidence were determined using the American College of Physicians grading system, and recommendations were discussed until consensus. Findings: Initial evaluation should include 25-hydroxyvitamin D measurement, 24-hour urine calcium measurement, dual-energy x-ray absorptiometry, and supplementation for vitamin D deficiency. Parathyroidectomy is indicated for all symptomatic patients, should be considered for most asymptomatic patients, and is more cost-effective than observation or pharmacologic therapy. Cervical ultrasonography or other high-resolution imaging is recommended for operative planning. Patients with nonlocalizing imaging remain surgical candidates. Preoperative parathyroid biopsy should be avoided. Surgeons who perform a high volume of operations have better outcomes. The possibility of multigland disease should be routinely considered. Both focused, image-guided surgery (minimally invasive parathyroidectomy) and bilateral exploration are appropriate operations that achieve high cure rates. For minimally invasive parathyroidectomy, intraoperative parathyroid hormone monitoring via a reliable protocol is recommended. Minimally invasive parathyroidectomy is not routinely recommended for known or suspected multigland disease. Ex vivo aspiration of resected parathyroid tissue may be used to confirm parathyroid tissue intraoperatively. Clinically relevant thyroid disease should be assessed preoperatively and managed during parathyroidectomy. Devascularized normal parathyroid tissue should be autotransplanted. Patients should be observed postoperatively for hematoma, evaluated for hypocalcemia and symptoms of hypocalcemia, and followed up to assess for cure defined as eucalcemia at more than 6 months. Calcium supplementation may be indicated postoperatively. Familial pHPT, reoperative parathyroidectomy, and parathyroid carcinoma are challenging entities that require special consideration and expertise. Conclusions and Relevance: Evidence-based recommendations were created to assist clinicians in the optimal treatment of patients with pHPT.

Low-Grade Persistent Hyperparathyroidism After Pediatric Renal Transplant.

OBJECTIVES: Hyperparathyroidism, a frequent complication of chronic kidney disease, persists after renal transplant. Our aims were to examine the status of parathyroid hormone levels and to determine the clinical and biochemical risk factors of persistent hyperparathyroidism after transplant. MATERIALS AND METHODS: Our study included 44 pediatric renal transplant recipients with stable graft function. Median follow-up after transplant was 17.5 months (range, 12-126 mo). Patients did not receive routine vitamin D or calcium supplements after transplant, and none had undergone previous parathyroidectomy. Bone mineral densitometry of the lumbar spine was measured. RESULTS: Fifteen patients (34%) had parathyroid hormone levels greater than 70 pg/mL (normal range, 10-70 pg/mL). Duration of dialysis before transplant was longer in patients with persistent hyperparathyroidism. Mean serum bicarbonate levels were significantly lower in patients with persistent hyperparathyroidism than in patients without persistent hyperparathyroidism after transplant. A significant negative correlation was noted between parathyroid hormone level and serum bicarbonate level. Another significant negative correlation was shown between parathyroid hormone level and z score. CONCLUSIONS: We found that persistent hyperparathyroidism is related to longer dialysis duration, lower serum bicarbonate level, and lower z score. Pretransplant dialysis duration is an important predictor of persistent hyperparathyroidism. Early identification of factors that contribute to persistent hyperparathyroidism after transplant could lead to treatment strategies to minimize or prevent its detrimental effects on bone health and growth in pediatric transplant recipients.

Prevalence of vitamin D deficiency in peritoneal dialysis patients.

Peritoneal dialysis (PD) patients have a high risk of developing vitamin D deficiency as 25(OH) vitamin D, the precursor of active vitamin D, is lost during dialysis. This cross-sectional study was conducted to investigate the prevalence of vitamin D deficiency among adult Saudi patients on regular PD The data was collected in the summer of 2010 from patients who were on PD for more than six months at the King Khalid University Hospital, Riyadh. We recorded the demographic and clinical parameters for all patients. Blood samples were taken for serum vitamin D level (25 OH), serum parathyroid hormone (PTH) levels and other necessary biochemical parameters. There were 27 patients (11 males and 16 females) with a mean age of 46 (15-78 ± 21) years. Five patients were on continuous ambulatory PD and 22 patients were using automated PD. The average time on PD was 27.5 (6-84 ± 18.5) months. The mean serum vitamin D 25 (OH) level was 16.1 (4.9-41.5 ± 8.23) nmol/L. Sixteen (59.2%) of the patients had levels below 15 nmol/L, while another eight patients (29.6%) had vitamin D levels between 15 and 25 nmol/L, indicating a marked deficiency. The mean serum calcium was 2.2 (1.7-2.6 ± 0.2) mmol/L and the mean serum phosphorous was 1.48 (0.64-2.22 ± 0.37) mmol/L. Fifteen patients (55.5%) had significant hyperparathyroidism (serum PTH levels above 30 pmol/L). Majority of the PD patients in our center had vitamin D deficiency. The possible reasons include chronic renal failure, dietary restrictions, loss of vitamin D and decreased exposure to sunlight.

Molecular and clinical analysis of a neonatal severe hyperparathyroidism case caused by a stop mutation in the calcium-sensing receptor extracellular domain representing in effect a human 'knockout'.

OBJECTIVE: Loss-of-function calcium-sensing receptor (CAR) mutations cause elevated parathyroid hormone (PTH) secretion and hypercalcaemia. Although full Car deletion is possible in mice, most human CAR mutations result from a single amino acid substitution that maintains partial function. However, here, we report a case of neonatal severe hyperparathyroidism (NSHPT) in which the truncated CaR lacks any transmembrane domain (CaR(R392X)), in effect a full CAR 'knockout'. CASE REPORT: The infant (daughter of distant cousins) presented with hypercalcaemia (5.5-6  mmol/l corrected calcium (2.15-2.65)) and elevated PTH concentrations (650-950  pmol/l (12-81)) together with skeletal demineralisation. NSHPT was confirmed by CAR gene sequencing (homozygous c.1174C-to-T mutation) requiring total parathyroidectomy during which only two glands were located and removed, resulting in normalisation of her serum PTH/calcium levels. DESIGN AND METHODS: The R392X stop codon was inserted into human CAR and the resulting mutant (CaR(R392X)) expressed transiently in HEK-293 cells. RESULTS: CaR(R392X) expressed as a 54  kDa dimeric glycoprotein that was undetectable in conditioned medium or in the patient's urine. The membrane localisation observed for wild-type CaR in parathyroid gland and transfected HEK-293 cells was absent from the proband's parathyroid gland and from CaR(R392X)-transfected cells. Expression of the mutant was localised to endoplasmic reticulum consistent with its lack of functional activity. CONCLUSIONS: Intriguingly, the patient remained normocalcaemic throughout childhood (2.5 mM corrected calcium, 11 pg/ml PTH (10-71), age 8 years) but exhibited mild asymptomatic hypocalcaemia at age 10 years, now treated with 1-hydroxycholecalciferol and Ca2+ supplementation. Despite representing a virtual CAR knockout, the patient displays no obvious pathologies beyond her calcium homeostatic dysfunction.

[Clinical and laboratory parameters in patients with urolithiasis in the presence and absence of primary hyperparathyroidism].

The clinical and laboratory findings in 78 patients with various forms of urolithiasis depending on the presence of primary hyperparathyroidism (PHPT) were analyzed. PHPT was diagnosed in 17 patients. Group "without PHPT" and group "with PHPT" differed significantly in terms of parathyroid hormone (PTH) level, serum calcium, phosphorus, chloride, alkaline phosphatase, calciuria and kaliuria. In patients with staghorn calculi, PHPT was diagnosed in 12.5%, and staghorn calculi in the presence of PHPT were identified in 17.7% of cases. Hypercalciuria in the group "with PHPT" was detected in 82.4% of patients (all 3 patients with staghorn calculi), and in the group "without PHPT"--in 18% of patients (2 of 21 patients with staghorn calculi). Hyperoxaluria was observed in 42.3% of patients "without PHPT" and in 35.3% of patients "with PHPT", in 36.8% of patients with simple stones and in 57.2%--with staghorn calculi. In 39% of patients "without PHPT", secondary hyperparathyroidism (SHPT) was diagnosed. SHPT prevalence was 28% in patients with staghorn calculi, and 45% in patients with simple stones. In 87.5% of patients with hypomagnesemia, staghorn calculi were observed. Significant relationship between magnesium and triglycerides (r(s) = -0.296; P = 0.041), and magnesium and high-density lipoproteins (r(s) = 0.339; P = 0.032) in all patients with urolithiasis were revealed. Thus, the study found no association between staghorn nephrolithiasis and PHPT. Elevated PTH levels usually indicate SHPT rather than PHPT. In hypocalcemia, there was more strong association between PTH and calcium, in normocalcaemia--between PTH and magnesium.

Endocrine causes of calcium disorders.

Endocrine diseases that may cause hypercalcemia and hypocalcemia include hyperparathyroidism, hypoparathyroidism, thyroid disorders, hyperadrenocorticism, hypoadrenocorticism, and less commonly pheochromocytoma and multiple endocrine neoplasias. The differential diagnosis of hypercalcemia may include malignancy (lymphoma, anal sac carcinoma, and squamous cell carcinoma), hyperparathyroidism, vitamin D intoxication, chronic renal disease, hypoadrenocorticism, granulomatous disorders, osteolysis, or spurious causes. Hypocalcemia may be caused by puerperal tetany, pancreatitis, intestinal malabsorption, ethlyene glycol intoxication, acute renal failure, hypopararthyroidism, hypovitaminosis D, hypomagnesemia, and low albumin. This article focuses on the endocrine causes of calcium imbalance and provides diagnostic and therapeutic guidelines for identifying the cause of hypercalcemia and hypocalcemia in veterinary patients.

Long-term evolution of the mineral metabolism after renal transplantation: a prospective, single-center cohort study.

BACKGROUND: Abnormalities in bone and mineral metabolism are common after renal transplantation (RT) but information on their long-term time course is scarce. OBJECTIVES: (1) Evaluate the time course of biochemical parameters of bone and mineral metabolism over 60 months after RT; (2) identify predictors for persistent hyperparathyroidism (HPT). DESIGN: Prospective, longitudinal, single-center cohort study. METHODS: We determined serum levels (mean values ± standard deviations) of intact parathyroid hormone (iPTH), calcium (Ca), phosphorus (P), magnesium (Mg), alkaline phosphatase (APh), calcitriol, and creatinine (Cr) preoperatively as well as 6, 12, 24, 36, 48, and 60 months after cadaveric RT in 49 patients. We in addition recorded demographic, clinical, and therapeutic data. RESULTS: Pretransplantation iPTH stabilized from 194.2 ± 273.5 to 71.5 ± 50.7 ng/L at 6 months. Serum Ca (9.5 ± 1.1 mg/dL) and APh (81.9 ± 42.1 U/L) did not change. Baseline serum P (5.7 ± 1.8 mg/dL) and serum Mg (2.4 ± 0.4 mg/dL) decreased to normal ranges from month 6 onward. Low baseline calcitriol (22.4 ± 21.8 pmol/L) normalized slowly by 12 months (95.4 ± 46.7 pmol/L). Stable graft function (53.2 ± 15.8 mL/min) was achieved from 6 months onward. By 60 months, 26.5% of patients had a serum Ca above 9.8 mg/dL and serum P below 2.7 mg/dL; 22.4%, an Mg below 1.7 mg/dL and 8.2%, a serum iPTH more than 2.5-fold the upper limit of normal. Upon multiple regression analyses the iPTH at 60 months was influenced by a dialysis duration ≥ 2 years (ß = 0.259, P = .003), body mass index > 25 kg/m(2) (ß = 0.257, P = .006), baseline iPTH (ß = 0.182, P = .036), serum Cr (ß = 0.268, P = .002) and Mg (ß = -0.242, P = .006). CONCLUSIONS: Hypercalcemia, hypophosphatemia, hypomagnesemia, and elevated iPTH persist in a subset of post-RT patients. Pretransplantation iPTH and obesity, dialysis duration, and posttransplant serum creatininemia and hypomagnesemia independently contribute to persistent HPT.

Primary hyperparathyroidism as the first clinical manifestation of multiple endocrine neoplasia type 2A in a 5-year-old child.

BACKGROUND: Primary hyperparathyroidism occurs in only 10%-30% of patients with multiple endocrine neoplasia type 2A (MEN2A), rarely as the sole clinical manifestation, and is usually diagnosed after the third decade of life. SUMMARY: A 5-year-old girl was referred for prophylactic thyroidectomy as she carried the p.C634R RET mutation. She was clinically asymptomatic, with a normally palpable thyroid and with the cervical region free of lymphadenopathy or other nodules. Preoperative tests revealed hypercalcemia associated with elevation of parathyroid hormone (PTH) (calcium = 11.2 mg/dL, calcium ion = 1.48 mmol/L, phosphorus = 4.0 mg/dL, alkaline phosphatase = 625 U/L, parathyroid hormone (PTH) PTH = 998 pg/mL). A thyroid ultrasound was normal and parathyroid scintigraphy with (99m)Tc-Sestamibi revealed an area of radioconcentration in the upper half of the left thyroid lobe suggesting hyperfunctioning parathyroid tissue. She underwent total thyroidectomy and parathyroidectomy and developed hypocalcemia. The anatomopathological examination showed no histopathological changes in the thyroid tissue and an adenoma of the parathyroid gland, confirming the diagnosis of hyperparathyroidism. CONCLUSIONS: Primary hyperparathyroidism can be a precocious manifestation of MEN2A. This case report highlights that asymptomatic hypercalcemia should be scrutinized in children related to patients with MEN2A who carry a mutation in the RET proto-oncogene, especially mutations in the codon 634, before the currently recommended age of 8 years.