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Reliability of Serum Calcium to Phosphorus (Ca/P) Ratio as an Accurate and Inexpensive Tool to Define Disorders of Ca-P Metabolism

Completed
Conditions
Phosphorus and Calcium Disorders
Registration Number
NCT03603444
Lead Sponsor
Azienda Ospedaliero-Universitaria di Modena
Brief Summary

BACKGROUND: Primary hyperparathyroidism (PHPT) is the third most common endocrine disorder. The Ca/P ratio is an accurate tool to differentiate patients with PHPT (\>3.5 if Ca and P are expressed in mg/dl) from healthy subjects. The reliability of this index is based on the fact that serum Ca and P are inversely related together. However, other disorders of the Ca-P metabolism, such as hypophosphoremia (HypoP) not related to PHPT, might also impair the Ca/P ratio.

OBJECTIVE: To validate the accuracy of Ca/P ratio in the diagnosis of Ca-P metabolism disorders, including also patients with documented HypoP not related to PHPT.

METHODS: A single-center, retrospective, case-control study will be carried out.

Biochemical measurements will include parathormone (PTH), vitamin D, serum Ca and P, serum albumin and creatinine.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
606
Inclusion Criteria
  • patients with diagnosis of primary hyperparathyroidism
  • HIV-infected patients with reduced phosphorus but normal calcium
  • subjects with normal Calcium-Phosphorus metabolism

Exclusion criteria for both cases and controls will be:

  • age younger than 18 or older than 90 years
  • severe renal and liver diseases (i.e. glomerular filtration rate (GFR) <30 ml/min)
  • hyperparathyroidism secondary to Vitamin D deficiency
  • active metabolic bone disease (e.g. Paget's disease of the bone, osteomalacia, rickets, etc)
  • any type of cancer
  • malnutrition
  • severe obesity (BMI > 40 kg/m2)
  • a history of gastrointestinal malabsorption
  • sarcoidosis
  • hypercortisolism
  • diabetes insipidus
  • hyperthyroidism
  • pseudohypoparathyroidism
  • familial hypocalciuric hypercalcemia (FHH)
  • treatment with steroids, active forms of vitamin D (calcitriol, ergocalciferol, etc), thiazides, phosphate binders, lithium, cinacalcet, bisphosphonates, and denosumab.
Exclusion Criteria

Not provided

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Primary Outcome Measures
NameTimeMethod
Serum Calcium to Phosphorus ratioAssessed only once at the diagnosis (from January 2005 to January 2018)

Calculated formula (serum calcium to serum phosphorus ratio)

Secondary Outcome Measures
NameTimeMethod
Serum CalciumAssessed only once at the diagnosis (from January 2005 to January 2018)

From blood sample - Unit of measurement: mg/dl

Serum PhosphorusAssessed only once at the diagnosis (from January 2005 to January 2018)

From blood sample - Unit of measurement: mg/dl

Serum ParathormoneAssessed only once at the diagnosis (from January 2005 to January 2018)

From blood sample - Unit of measurement: pg/ml

Trial Locations

Locations (1)

Azienda Ospedaliero - Universitaria di Modena

🇮🇹

Modena, Italy

Azienda Ospedaliero - Universitaria di Modena
🇮🇹Modena, Italy

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