Parathyroidectomy leads to decreased blood lead levels in patients with refractory secondary hyperparathyroidism

Hong Kong poison information centre: Annual report 2020

Background:

The Hong Kong Poison Information Centre has provided consultation service to healthcare professionals and collected epidemiological data on poisoning in Hong Kong since 2005.

Objective:

To analyse and report the poisoning data of Hong Kong Poison Information Centre in 2020 during the COVID-19 pandemic.

Methods:

A retrospective review of all poisoning cases recorded in the Poison Information and Clinical Management System of Hong Kong Poison Information Centre in 2020.

Results:

A total of 3633 poisoning cases were analysed. Compared to 2019 (pre-COVID era), there was a reduction of ~10% of total poisoning cases recorded (383 cases), with a majority (> 90%) of reduction from poisoning cases with no clinical effect (353 cases). A greater proportion of reduction was observed among the children (0–12 years), patients with general unintentional poisoning, poisoning due to therapeutic error and food poisoning. An increased number of cases was noted from abusive use, adverse herb/proprietary Chinese medicine reaction and poisoning related to household bleaches. Teenage (13–19 years) poisoning seemed to be unaffected by the COVID-19 pandemic and the previously observed increasing trend continued (up to 11.8% of total poisoning cases this year). Despite a total reduction in poisoning cases recorded, the number of deaths increased by 37% from 35 in 2019 to 48 in 2020 (mortality rate 1.5%). A total of seven interesting cases were discussed.

Conclusion:

This 15th annual report provides updated epidemiological information on poisoning patterns in Hong Kong during the COVID-19 pandemic. It also highlighted important changes and possible effects of the COVID-19 pandemic on poisoning in Hong Kong in comparison with our previous reports.

Influence of Parathyroidectomy on Bone Metabolism and Bone Pain in Patients with Secondary Hyperparathyroidism

BACKGROUND

After parathyroidectomy (PTX), hungry bone syndrome leads to hypocalcemia due to bone remineralization. The aim of this pilot study was to analyze changes in markers of bone metabolism in patients with secondary hyperparathyroidism (sHPT) after PTX and to correlate these markers with bone pain measured with a validated questionnaire.

MATERIALS AND METHODS

All patients who underwent PTX for sHPT between March 2010 and February 2012 at out institution were included in this prospective observational pilot study. At the day before surgery and on the 3rd day thereafter, levels of parathyroid hormone (PTH), calcium, osteocalcin, alkaline phosphatase (AP), bone-specific AP (BAP), tartrate-resistant acid phosphatase 5b (TRAP5b), osteoprotegerin (OPG), sclerostin, fibroblast growth factor 23, and Klotho were measured. Additionally, all patients were requested to answer the Brief Pain Inventory preoperatively and on the 5th postoperative day.

RESULTS

A total of 35 patients with a mean age of 49.8 years were analyzed. A significant difference between the pre- and postoperative values could be detected in PTH, calcium, BAP, TRAP5b, and sclerostin. The highest correlation of laboratory markers with bone pain was found for preoperative PTH (r = 0.3), postoperative OPG (r = 0.4), postoperative BAP (r = -0.4), and postoperative Klotho (r = -0.4).

CONCLUSIONS

The present study revealed significant perioperative changes in PTH, BAP, sclerostin, and TRAP5b after PTX. These markers may serve as laboratory markers to monitor bone metabolism in patients with sHPT. PTH, OPG, and sclerostin were the parameters with the closest correlation to bone pain. However, larger prospective trials with a longer follow-up are required to confirm these results.

Blood lead level is a positive predictor of uremic pruritus in patients undergoing hemodialysis

Although uremic pruritus (UP) is a common and annoying symptom for end-stage renal disease patients on hemodialysis (HD) and peritoneal dialysis, its pathogenesis is poorly understood. However, systemic inflammation is one of the possible pathogenesis of UP, and blood lead level (BLL) has been noted to be associated with inflammation and nutritional status in long-term HD patients. There might be an interaction or association, therefore, between BLL and UP through systemic inflammation. We analyzed cross-sectional data among 866 participants. All of the 866 patients in this study were stratified into groups with low-normal (<10 μg/dL), high-normal (10-20 μg/dL), and abnormal BLLs (>20 μg/dL). The associations between UP and BLL and the clinical data were analyzed. Multivariate logistic regression demonstrated that HD duration, non-anuria, log ferritin, serum low-density lipoprotein, log BLL, high-normal BLL, and high BLL were associated with UP. In conclusion, BLL was positively associated with UP.