Background: Hypercalciuria is frequent in patients with acromegaly, but it is unclear how GH/IGF-I regulate renal calcium handling. Elevated fasting plasma calcium levels despite increased glomerular filtration suggest enhanced renal calcium reabsorption.
Objective: The aim of this study was to investigate the impact of acromegaly on phosphocalcium metabolism.
Design And Setting: We conducted a prospective sequential study at a tertiary referral medical center and clinical investigation center (www.ClinicalTrials.gov Identifier: NCT00531908).
Intervention: Sixteen consecutive patients (five females/11 males) with acromegaly received a single iv infusion of 25 mg of furosemide to induce an acute increase in calcium and magnesium delivery to distal tubular segments during a high-sodium diet with stable dietary calcium, magnesium, and phosphate intake.
Measurements: Baseline plasma and urine electrolytes, plasma calciotropic hormones, and furosemide-induced changes in the fractional excretion and tubular reabsorption of Na, Ca, and Mg were measured before and 6 months (range, 1-12) after effective treatment of acromegaly.
Results: Serum IGF-I concentrations normalized in all the patients after acromegaly treatment. Compared with controlled acromegaly, active acromegaly was associated with higher fasting plasma (P = 0.0002) and urinary calcium (P = 0.0003) levels, lower PTH levels (P = 0.0075), higher calcitriol levels (P = 0.0137), higher phosphatemia (P<0.0001) and tubular phosphate reabsorption (P = 0.0002), and a lower calciuric (P = 0.0327) but not magnesiuric response to furosemide related to higher baseline and postfurosemide tubular calcium (P = 0.0034 and P = 0.0081, respectively), but not magnesium reabsorption.
Conclusion: The IGF-I-mediated and PTH-independent increase in calcitriol synthesis in acromegaly is responsible for both absorptive hypercalciuria and increased fasting plasma calcium linked to enhanced distal tubular calcium reabsorption, as shown by the selectively diminished calciuric response to furosemide.
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http://dx.doi.org/10.1210/jc.2011-3188 | DOI Listing |
Kidney Int
January 2025
Laboratório de Fisiopatologia Renal (LIM 16), Nephrology Department, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP), Universidade de São Paulo, São Paulo, Brazil. Electronic address:
In 2017, Kidney Disease: Improving Global Outcomes (KDIGO) published a Clinical Practice Guideline Update for the Diagnosis, Evaluation, Prevention, and Treatment of Chronic Kidney Disease-Mineral and Bone Disorder (CKD-MBD). Since then, new lines of evidence have been published related to evaluating disordered mineral metabolism and bone quality and turnover, identifying and inhibiting vascular calcification, targeting vitamin D levels, and regulating parathyroid hormone. For an in-depth consideration of the new insights, in October 2023, KDIGO held a Controversies Conference on CKD-MBD: Progress and Knowledge Gaps Toward Personalizing Care.
View Article and Find Full Text PDFJ Infect Dev Ctries
December 2024
Nephrology Department, UHC Mother Tereza, Tirane, Albania.
Introduction: Acute kidney injury involves inflammation and intrinsic renal damage, and is a common complication of severe coronavirus disease 2019 (COVID-19). Baseline chronic kidney disease (CKD) confers an increased mortality risk. We determined the renal long-term outcomes of COVID-19 in patients with baseline CKD, and the risk factors prompting renal replacement therapy (RRT) initiation and mortality.
View Article and Find Full Text PDFAnn Clin Biochem
January 2025
Department of Clinical Biochemistry, Aberdeen Royal Infirmary, NHS Grampian, Aberdeen, Scotland.
Background: International guidelines give greatly varying definitions of 25-hydroxyvitamin D (25OHD) insufficiency and deficiency. Vitamin D testing is increasing despite 2016 UK guidance for adults advising routine vitamin D supplementation October-March and year-round for high risk groups. A service evaluation of vitamin D testing and biochemical osteomalacia in the North-East of Scotland (57-58°N) could inform definitions and testing guidance.
View Article and Find Full Text PDFJ Clin Med
January 2025
Department of Renal Medicine, Tan Tock Seng Hospital, 11 Jalan Tan Tock Seng, Singapore 608433, Singapore.
: Parathyroidectomy (PTX) is generally curative in renal hyperparathyroidism (RHPT) that is refractory to medical treatment in end-stage kidney disease (ESKD) patients. Severe hypocalcemia is a common complication of PTX and results in increased monitoring, interventions, lengths of stay, and costs of care. This study aimed to find the determinants and cutoff values of the biochemical determinants, if any, for severe post-operative hypocalcemia after PTX in adult patients with ESKD.
View Article and Find Full Text PDFMedicina (Kaunas)
December 2024
Department of Dermatology, International University of Health and Welfare Narita Hospital, Chiba 286-8520, Japan.
Acquired reactive perforating dermatosis (ARPD) is characterized by its onset after the age of 18 years, umbilicated papules or nodules with a central keratotic plug, and the presence of necrotic collagen tissue within an epithelial crater. ARPD is strongly associated with systemic diseases such as diabetes mellitus (DM) and chronic renal failure, which may contribute to ARPD through factors including microcirculatory disturbances and the deposition of metabolic byproducts, including advanced glycation end-products and calcium. Here, we report a case of ARPD that improved following DM treatment and catheter-based interventions for peripheral artery disease (PAD).
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