Radioiodine dosimetry in patients with end-stage renal disease receiving continuous ambulatory peritoneal dialysis therapy

Modified Dose of Radioactive Iodine Therapy in a Patient With Thyroid Cancer on Peritoneal Dialysis: Case Report and Review of Literature

Thyroid malignancy is common among patients with renal impairment compared with the general population. Treatment involves surgical resection and radioactive iodine therapy (RAI) in high-risk patients. As a result of impaired iodine clearance in those with no residual kidney function, the determination of appropriate iodine dose is challenging. Evidence is lacking, and all previous reports are based on case studies with no universally accepted protocol.  We describe the case of a 30-year-old woman with end-stage renal disease on peritoneal dialysis (PD) who was diagnosed with papillary thyroid cancer while undergoing a pre-kidney transplant workup. She had a total thyroidectomy with modified radical neck dissection followed by a reduced-dose radioactive iodine therapy of 30 mCi based on her residual kidney function. Her PD prescription was adjusted to achieve a 2 L ultrafiltration daily. One year follow-up confirmed no evidence of residual nor recurrent disease. High-risk patients with differentiated thyroid malignancy require adjuvant radioactive iodine therapy. The optimal dose of RAI in the end-stage renal disease population is controversial. There are no clear guidelines available for patients with end-stage kidney disease including patients on peritoneal dialysis. Reduced dose therapy is probably effective in achieving the goals of therapy, with lower toxic risk to internal organs. Determining the appropriate schedule of each dialysis session in relation to RAI, the specific replacement prescription, and establishing a safe environment for medical staff dealing with such patients is important to consider. This article aims to highlight the need to establish a standardized protocol among patients with reduced kidney function treated with iodine therapy.

Safe use of radiopharmaceuticals in patients with chronic kidney disease: a systematic review

BACKGROUND

Patients with chronic kidney disease (CKD) may need to have their radiopharmaceutical dosage adjusted to prevent adverse effects and poor outcomes, but there are few recommendations on radiopharmaceutical dosing for this group of patients. The aim of this study is to provide an overview of the available information on radiopharmaceutical dose recommendations for patients with CKD.

METHODS

We performed a systematic literature review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We conducted a literature search in the MEDLINE (PubMed) and Embase databases and screened potentially relevant studies using inclusion and exclusion criteria. We independently assessed the included observational studies' methodologies and extracted relevant data.

RESULTS

Of the 5795 studies first identified, 34 were included in this systematic review. These studies described three radiopharmaceuticals: [131I]sodium iodine, [18F]fludeoxyglucose, and [131I]iobenguane. Twenty-nine studies (85.3%) reported data on patients with CKD stage 5, while only three studies mentioned CKD patients in other stages (8.8%).

CONCLUSION

We found no consistent recommendations for radiopharmaceutical dosing in patients with CKD. Although some studies do mention dosing difficulties in patients with CKD, information is available for only a few radiopharmaceuticals, and recommendations are sometimes contradictory. Further research on radiopharmaceutical dosing in patients with CKD is needed to determine whether these patients require specific dosing, especially for therapeutic radiopharmaceuticals where a non-optimised dose may lead to an increased risk of toxicity for non-targeted organs. Including patients with CKD in studies and providing specific information about dosing in these patients should be a priority for the radiopharmaceutical community.

Dosing of radioactive iodine in end-stage renal disease patient with thyroid cancer

We describe detailed administration of thyroidal and extrathyroidal doses of radioiodine to a patient with end-stage renal disease on hemodialysis. A thorough description of area under curve measurements in a patient with compromised renal function has rarely been described in the literature. Few publications have described thyroid cancer management of patients on hemodialysis, and we believe our management will aid in patient treatment in the future.

Interactions between thyroid disorders and kidney disease

There are several interactions between thyroid and kidney functions in each other organ's disease states. Thyroid hormones affect renal development and physiology. Thyroid hormones have pre-renal and intrinsic renal effects by which they increase the renal blood flow and the glomerular filtration rate (GFR). Hypothyroidism is associated with reduced GFR and hyperthyroidism results in increased GFR as well as increased renin - angiotensin - aldosterone activation. Chronic kidney disease (CKD) is characterized by a low T3 syndrome which is now considered a part of an atypical nonthyroidal illness. CKD patients also have increased incidence of primary hypothyroidism and subclinical hypothyroidism. The physiological benefits of a hypothyroid state in CKD, and the risk of CKD progression with hyperthyroidism emphasize on a conservative approach in the treatment of thyroid hormone abnormalities in CKD. Thyroid dysfunction is also associated with glomerulonephritis often by a common autoimmune etiology. Several drugs could affect both thyroid and kidney functions. There are few described interactions between thyroid and renal malignancies. A detailed knowledge of all these interactions is important for both the nephrologists and endocrinologists for optimal management of the patient.