Serum Calcium to Phosphorous Ratio (Ca/P) as a Simple, Inexpensive Screening Tool in the Diagnosis of Primary Hyperparathyroidism

Study Overview
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Brief Summary
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Background: Primary hyperparathyroidism (PHPT) is often overlooked and underdiagnosed. At present the diagnosis of PHPT remains challenging and is based on serum calcium (Ca) and PTH. As serum Ca and phosphorous (P) are inversely related in PHPT, the Ca/P ratio might be considered a good candidate tool in the diagnosis of PHPT. AIM: The aim of this study is to investigate the diagnostic value of the Ca/P ratio in the diagnosis of PHPT. Study design: Retrospective, observational, cross-sectional, case-control clinical trial will be carried out. Biochemical measurements will include PTH, Vitamin D, serum Ca, P, albumin, and creatinine.

Conditions
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Hyperparathyroidism

Intervention / Treatment
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* Other: No intervention are provided


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: elevated parathormone serum levels normal or elevated calcium serum levels Exclusion Criteria: age younger than 18 years renal and liver failure and insufficiency active metabolic bone disease (such as Paget's disease of the bone, osteomalacia, rickets, etc) any type of cancer malnutrition, severe obesity (BMI > 40 kg/m2) and malabsorption transplantation sarcoidosis endocrinological disorders such as hypercortisolism, diabetes insipidus, hyperthyroidism, pseudohypoparathyroidism familial hypocalciuric hypercalcemia hypophosphoremia sustained by genetic causes or secondary to other causes.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Study group<br>Patients aged between 18-90 years old with primary hyperparathyroidism who had been diagnosed in the Unit of Endocrinology of the University of Modena and Reggio Emilia. The exclusion criteria will be: age younger than 18 years renal and liver failure and insufficiency active metabolic bone disease (such as Paget's disease of the bone, osteomalacia, rickets, etc) any type of cancer malnutrition, severe obesity (BMI > 40 kg/m2) and malabsorption transplantation sarcoidosis endocrinological disorders such as hypercortisolism, diabetes insipidus, hyperthyroidism, pseudohypoparathyroidism familial hypocalciuric hypercalcemia hypophosphoremia sustained by genetic causes or secondary to other causes. | Other: No intervention are provided<br> <br> |
| Control group<br>Patients that underwent biochemical examination by primary care physician or by endocrinologist in order to assess their parathyroid function and calcium metabolism state with results into the normal ranges. The exclusion criteria will be: age younger than 18 years renal and liver failure and insufficiency active metabolic bone disease (such as Paget's disease of the bone, osteomalacia, rickets, etc) any type of cancer malnutrition, severe obesity (BMI > 40 kg/m2) and malabsorption transplantation sarcoidosis endocrinological disorders such as hypercortisolism, diabetes insipidus, hyperthyroidism, pseudohypoparathyroidism familial hypocalciuric hypercalcemia hypophosphoremia sustained by genetic causes or secondary to other causes. | Other: No intervention are provided<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Calcium | Assay performed at the moment of diagnosis | Enrollment time | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Phosphorus | Assay performed at the moment of diagnosis | Enrollment time | 
| Parathormone | Assay performed at the moment of diagnosis | Enrollment time | 
| Creatinine | Assay performed at the moment of diagnosis | Enrollment time | 
| Albumine | Assay performed at the moment of diagnosis | Enrollment time | 
| Vitamin D | Assay performed at the moment of diagnosis | Enrollment time |