Ultrasound Detection of Parathyroid Hyperplasia and Correlation with Clinicial and Laboratory Findings in Patients with Chronic Kidney Disease

Objective: To determine whether there is any correlation between parathyroid hyperplasia, as detected by high-resolution ultrasound, and clinical and laboratory variables in patients with hyperparathyroidism secondary to stage-5 chronic kidney disease (CKD) on hemodialysis. Design: Descriptive. Location: RTS Ltda. Renal Unit in Caldas, Santa Sofía Hospital and Children’s Hospital. Patients: All patients, 18 years of age, with stage – 5 CKD who were on dialysis therapy (hemodialysis or peritoneal dialysis), and with PTH levels greater than 400 pg / ml. methods: After giving their written consent to participate in the study, all patients underwent high-resolution thyroid and parathyroid ultrasound (Phillips Team Enviisor CHD 12 mHz transducer) performed by a medical specialist in radiology. Variables such as etiology, duration of the CKD, time on dialysis therapy, type of dialysis, presence of symptoms related to hyperparathyroidism (bone pain, fractures, pruritus),and laboratory variables like an intact PTH, calcium, phosphorus, calcium x phosphorus, and alkaline phosphatase were analyzed in order to determine if there was a significant correlation between the variables and the detection of parathyroid hyperplasia documented by high resolution ultrasound. Results: Of 403 patients evaluated, 92 met the inclusion criteria, 86 were scanned and 6 were excluded. In these patients, the most common cause of CKD was hypertensive nephrosclerosis. Thirtyseven patients were on peritoneal dialysis and 49 on hemodialysis, with an average time on dialysis of 61.4 ± 36.6 months. The average levels of PTH in pg / mL were 829,465 ± 473,631. The most prevalent clinical symptom was bone pain, found in 52.2% of patients. Ultrasound showed enlarged parathyroid glands in 30 patients (34.88%), with single-gland hyperplasia in 23 (26.74%), two-gland hyperplasia in 4 (4.65%) and three-gland hyperplasia in 3 (3.48%). The correlation between laboratory variables and the presence of parathyroid hyperplasia showed no statistical significance when compared with the group without ultrasound documentation of enlarged parathyroid glands. Conclusion: Parathyroid hyperplasia may be present in any patient with stage-5 CKD and intact PTH levels greater than 400 pg/ml, regardless of the clinical and laboratory variables. Ultrasound should be performed in all patients with high PTH values in order to refer them to the appropriate therapy.