When non-surgical methods fail, patients with secondary or renal hyperparathyroidism will have their parathyroid glands removed as part of the treatment. Now, they can have their parathyroid function restored at the Singapore General Hospital (SGH) using an innovative method that is simple, effective and non-invasive. Patients also walk away scar free.
A team of surgeons from SGH and National Cancer Centre Singapore (NCCS) has found that this new method promotes faster recovery and can be performed in nearly half the time that the conventional method requires.
Secondary or renal hyperparathyroidism is a condition that affects end-stage renal disease (ESRD) patients who have undergone haemodialysis for many years. Some studies have shown that it affects as many as three in 10 patients. The numbers are expected to rise as more patients are diagnosed with ESRD. About five to 15 per cent of patients with renal hyperparathyroidism would eventually need to remove their parathyroid glands.
The parathyroid glands are located in the neck, adjacent to the thyroid gland. They play a vital role in maintaining proper levels of calcium, phosphorus, and vitamin D levels in the blood and bone.
“The parathyroid glands work like a thermostat of an air-conditioning unit. When calcium levels are too low, they respond by ‘turning on’ the secretion of the parathyroid hormone to boost the calcium levels in the blood and vice versa when the calcium levels are too high. In patients with end-stage renal disease, where calcium levels are initially low, the secretion of parathyroid hormone is ‘turned on’ in an attempt to normalise calcium levels. Over time, parathyroid hormone secretion is permanently ‘turned on’ despite normal or even high calcium levels in the blood. This leads to renal hyperparathyroidism, which may cause bone diseases and cardiovascular diseases if left untreated, said Dr Jeremy Ng, Consultant, Department of General Surgery, SGH.
“Surgeons typically dice a very small portion of the removed gland and implant it into the deltoid muscle to restore parathyroid function in patients whose parathyroid glands have been removed. However, we postulated that injecting finely minced parathyroid tissue just under the skin in the same region would yield similar results,” said Dr Gopal Iyer, Senior Consultant, Division of Surgical Oncology, NCCS.
A retrospective study of 132 patients led by Drs Ng and Iyer to compare outcomes of those who were treated at SGH between February 2005 and February 2012 proved that their postulation was correct. The data shows that the injection method works better and parathyroid recovery was also significantly faster. It took merely two months for the group who were injected as compared to nine months for patients who had implantation. The average time required to perform the injection method was also much shorter than the conventional method i.e. 18 minutes versus 30 minutes respectively.
“Synergy amongst various departments is crucial in the care of end-stage renal disease patients who are on dialysis and may develop renal hyperparathyroidism. Not only did we introduce this new technique that yield better patient outcomes, we have also developed a dedicated care plan, the first in the region, with our renal specialists, renal nurse clinicians and dialysis coordinators to look after these patients even after they are discharged,” said Dr Ng, who is also the co-lead investigator of the study.
The new technique is now adopted at SGH to restore patients’ parathyroid function.