CaPTHUS Score (Single-Gland Primary Hyperparathyroidism)
The CaPTHUS score (Kebebew and colleagues 2006) predicts single-gland disease in a patient already diagnosed with primary hyperparathyroidism.
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Ca - Preoperative total serum calcium at or above 12 mg/dL (3 mmol/L)?
- Yes
- PTH - Intact PTH at or above twice the upper limit of the reference range?
- Yes
- U - Neck ultrasound positive for ONE enlarged parathyroid gland?
- Yes
- S - Sestamibi scan positive for ONE enlarged parathyroid gland?
- No
- + - The ultrasound and the sestamibi are CONCORDANT: the same single gland, on…
- No
Result: CaPTHUS 3 of 5.
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Ca
- Preoperative total serum calcium at or above 12 mg/dL, equivalently 3 mmol/L. Not 3 mg/dL.
- PTH
- Intact PTH at or above twice the upper limit of normal.
- U and S
- Ultrasound and sestamibi each positive for ONE enlarged gland.
- Concordance
- Scored separately: two positive scans pointing at different glands score 2, not 3.
- 3 or more
- Predicted single-gland disease with a positive predictive value of 100 percent in the derivation cohort. External validation runs lower.
- Below 3
- The negative predictive value is poor. This does not predict multigland disease.
What you enter
- Ca - Preoperative total serum calcium at or above 12 mg/dL (3 mmol/L)?
- PTH - Intact PTH at or above twice the upper limit of the reference range?
- U - Neck ultrasound positive for ONE enlarged parathyroid gland?
- S - Sestamibi scan positive for ONE enlarged parathyroid gland?
- + - The ultrasound and the sestamibi are CONCORDANT: the same single gland, on the same side?
Full field descriptions
- Ca - Preoperative total serum calcium at or above 12 mg/dL (3 mmol/L)? Note the unit: 12 mg/dL, equivalently 3 mmol/L. Reading the 3 as mg/dL would award this point to almost every patient.
- PTH - Intact PTH at or above twice the upper limit of the reference range? Twice the upper limit of normal, not twice the mid-range and not simply elevated.
- U - Neck ultrasound positive for ONE enlarged parathyroid gland? One gland, not simply an abnormal study.
- S - Sestamibi scan positive for ONE enlarged parathyroid gland? One gland, not simply an abnormal study.
- + - The ultrasound and the sestamibi are CONCORDANT: the same single gland, on the same side? Scored separately from the two scans being individually positive. Two positive scans pointing at DIFFERENT glands score 2 here, not 3.
How this is calculated
Kebebew E, Hwang J, Reiff E, Duh QY, Clark OH. Predictors of single-gland vs multigland parathyroid disease in primary hyperparathyroidism: a simple and accurate scoring model. Arch Surg. 2006;141(8):777-782. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.