Parathyroidectomy for nephrolithiasis in primary hyperparathyroidism: Beneficial but not a panacea

Screening for asymptomatic nephrolithiasis in primary hyperparathyroidism patients is warranted

BACKGROUND

We aimed to investigate the prevalence, characteristics, and management of nephrolithiasis in primary hyperparathyroidism (PHPT) patients.

METHODS

Medical records of patients who underwent parathyroidectomy at a tertiary care hospital in British Columbia from January 2016 to April 2023 were retrospectively reviewed. Demographic data, laboratory results, imaging reports, and urologic consultations were examined. Descriptive statistics and relevant statistical tests, including logistic regressions, were utilized for data analysis.

RESULT

Of the 413 PHPT patients included in the study population, 41.9% harbored renal stones, and nearly half (48.6%) required urological interventions. Male sex, elevated preoperative serum ionized calcium (iCa) and 24-h urinary calcium (24 ​h urine Ca) levels were independent risk factors for stone formation. Additionally, male sex, younger age, and lower preoperative serum 25-hydroxyvitamin D (25(OH)D) level were associated with higher odds of requiring urological intervention for stones.

CONCLUSIONS

This study identified significant prevalence of asymptomatic renal calcifications in PHPT patients, with a substantial proportion necessitating urological intervention. These findings emphasize the importance of incorporating screening and treatment of renal stones into the management of PHPT patients.

Systematic review of the risk of urolithiasis following parathyroidectomy in patients with primary hyperparathyroidism

OBJECTIVE

Parathyroidectomy (PTX) is the conclusive therapy for primary hyperparathyroidism (PHPT), but its effect on the risk of urolithiasis is inconclusive. We comprehensively reviewed the currently available research to investigate the impact of PTX on the likelihood of urolithiasis among individuals suffering PHPT.

METHODS

Internet-based articles in English language released on Cochrane, PubMed, Scopus, Web of knowledge, and Embase up to September, 2023 were comprehensively reviewed. Each publication in contrast to the incidence, occurrence, or recurrence of urolithiasis after PTX versus medical treatment in PHPT patients was included. The outcome with pooled relative risks (RRs) and corresponding 95% confidence intervals (CIs) was examined employing DerSimonian and Laird's model of random effects. To determine the range of the real effect size of a future study in 95% of all populations, a prediction interval (PI) was also established.

RESULTS

Finally, ten studies involving 74,190 patients were included. Results from randomized-controlled trials (RCTs) and observational studies (OSs) both revealed that PTX did not substantially lessen the vulnerability of urolithiasis among individuals with PHPT (RCTs: pooled relative risk [RR] 0.42, 95%CI 0.13-1.41, p = 0.163; OSs: pooled RR 1.37, 95%CI 0.96 to 1.97, p = 0.084). The PI (RCT: 0.03 to 5.96; OSs: 0.44-4.20) containing 1.0 suggested the possibility of consistent results in future studies. Subgroup and sensitivity analyses supported the above findings, and no evidence showed publication bias.

CONCLUSION

Our analysis from the available RCTs or OSs did not give adequate or exact proof that the average effect of PTX lowers the incidence of urolithiasis among PHPT persons based on the random-effects model. Future research shall take into account the common effect of PTX as well as the prerequisites of preventive stone procedures, which will further help us assess the effectiveness of PTX in reducing kidney calculus comorbidity and develop techniques to avoid stone sequelae in these individuals.

Older Patients With Asymptomatic Primary Hyperparathyroidism: Should Criteria for Surgery Be Expanded?

Context

Patients with primary hyperparathyroidism (PHPT) can present with variable signs, symptoms, and end-organ effects. Clinical practice guidelines influence referral for consideration of parathyroidectomy.

Objective

This study compared the demographic, biochemical, and symptom profile and examine indications for surgery in patients older than 50 years who underwent parathyroidectomy to determine how changes to current guidelines may affect recommendations for parathyroidectomy.

Methods

A retrospective review was conducted of patients age 50 years or older who underwent initial parathyroidectomy for sporadic PHPT from 2012 to 2020. Patients were classified by indications for surgery per guideline criteria (classic, asymptomatic, and no criteria met) and age group (AG): 50 to 59 years; 60 to 69 years; 70 years or older. Patients were treated at a high-volume tertiary medical center by endocrine surgeons.

Results

Of 1182 patients, 367 (31%) classic and 660 (56%) asymptomatic patients met the criteria for surgery. The most common indications for surgery were extent of hypercalcemia (51%), osteoporosis (28%), and nephrolithiasis (27%). Of the 155 (13%) patients who did not meet the criteria, neurocognitive symptoms (AG1: 88% vs AG2: 81% vs AG3: 70%; P = .14) and osteopenia (AG1: 53% vs AG2: 68% vs AG3: 68%; P = .43) were frequently observed regardless of patient age. If the age threshold of younger than 50 years was expanded to 60, 65, or 70 years, an additional 61 (5%), 99 (8%), and 124 (10%) patients in the entire cohort would have met the guideline criteria for surgery, respectively.

Conclusion

Expanding current guidelines for PHPT to include a broader age range, osteopenia, and neurocognitive symptoms may allow for earlier surgical referral and evaluation for definitive treatment.

Kidney Stone Events Following Parathyroidectomy vs Nonoperative Management for Primary Hyperparathyroidism

CONTEXT

Primary hyperparathyroidism (PHPT) is associated with an increased risk of kidney stones. Few studies account for PHPT severity or stone risk when comparing stone events after parathyroidectomy vs nonoperative management.

OBJECTIVE

Compare the incidence of kidney stone events in PHPT patients treated with parathyroidectomy vs nonoperative management.

DESIGN

Longitudinal cohort study with propensity score inverse probability weighting and multivariable Cox proportional hazards regression.

SETTING

Veterans Health Administration integrated health care system.

PATIENTS

A total of 44 978 patients with > 2 years follow-up after PHPT diagnosis (2000-2018); 5244 patients (11.7%) were treated with parathyroidectomy.

MAIN OUTCOMES MEASURE

Clinically significant kidney stone event.

RESULTS

The cohort had a mean age of 66.0 years, was 87.8% male, and 66.4% White. Patients treated with parathyroidectomy had higher mean serum calcium (11.2 vs 10.8mg/dL) and were more likely to have a history of kidney stone events. Among patients with baseline history of kidney stones, the unadjusted incidence of ≥ 1 kidney stone event was 30.5% in patients managed with parathyroidectomy (mean follow-up, 5.6 years) compared with 18.0% in those managed nonoperatively (mean follow-up, 5.0 years). Patients treated with parathyroidectomy had a higher adjusted hazard of recurrent kidney stone events (hazard ratio [HR], 1.98; 95% CI, 1.56-2.51); however, this association declined over time (parathyroidectomy × time: HR, 0.80; 95% CI, 0.73-0.87).

CONCLUSION

In this predominantly male cohort with PHPT, patients treated with parathyroidectomy continued to be at higher risk of kidney stone events in the immediate years after treatment than patients managed nonoperatively, although the adjusted risk of stone events declined with time, suggesting a benefit to surgical treatment.

Development and validation of a nomogram for risk prediction of nephrolithiasis recurrence in patients with primary hyperparathyroidism

BACKGROUND

Nephrolithiasis is a common complication of primary hyperparathyroidism (PHPT), and the recurrence of nephrolithiasis in patients with PHPT is also an urgent concern. What is worse, there is a scarcity of recommended evaluation to predict the risk of nephrolithiasis recurrence in patients with PHPT. This study was aimed to develop and validate a nomogram to facilitate risk assessment in patients with PHPT.

METHODS

A total of 197 patients with PHPT were retrospectively included in this study from September 2016 to August 2021. Patients' demographic data, blood test parameters, urinalysis, stone parameters, and surgical intervention were collected. Extracted variables were submitted to a least absolute shrinkage and selection operator (LASSO) regression model. A nomogram was built and validated according to the area under the curve (AUC) value, calibration curve, and decision curve analysis.

RESULTS

According to the LASSO regression and logistic regression analyses, five predictors were derived from 22 variables: creatinine, uric acid, bilateral stone, multiplicity, and surgery. The AUC and concordance index of the training cohort and validation cohort were 0.829 and 0.856, and 0.827 and 0.877, respectively. The calibration curve analysis and the decision curve analysis showed that the nomogram had an adequate prediction accuracy.

CONCLUSION

We built a useful nomogram model to predict the risk of nephrolithiasis recurrence in patients with PHPT. This would assist clinicians to provide appropriate advices and managements for these patients.