Atrial fibrillation induced by post-parathyroidectomy transient thyrotoxicosis

Thyroiditis After Parathyroidectomy

Various clinical manifestations of thyroiditis after parathyroidectomy have been reported in the literature, ranging from mild symptoms to tachyarrhythmias and myocardial infarction. We report 2 cases of post-parathyroidectomy thyroiditis. Both patients had primary hyperparathyroidism and underwent parathyroidectomy for a solitary parathyroid adenoma. They subsequently developed symptoms of hyperthyroidism, including palpitations and heat intolerance. Laboratory investigations demonstrated a suppressed TSH level with elevated free T4 levels and low uptake on thyroid radioiodine scan, confirming the diagnosis of thyroiditis. The patients were managed conservatively, and their symptoms gradually resolved with normalization of thyroid hormone levels. A review of 27 cases reported to date reveals that this condition is mostly attributed to manipulation of the thyroid during parathyroid surgery. It occurs more frequently in patients who undergo 4-gland parathyroidectomy for secondary or tertiary hyperthyroidism and is self-limited within a few weeks. The case reports highlight the importance of recognizing thyroiditis as a potentially underrecognized complication of parathyroid surgery. Further research is warranted to better understand the underlying pathophysiology and to establish potential risk factors for its development post-parathyroidectomy.

Clinical study on the status of transient thyrotoxicosis after surgery for secondary hyperparathyroidism patients with end-stage renal disease and normal thyroid function

Objective

Secondary hyperparathyroidism (SHPT) is a common complication of end-stage renal disease (ESRD), and part of SHPT patients need receive parathyroidectomy (PTX). However, as an important postoperative complication of SHPT, thyrotoxicosis has received little attention. Therefore, in this article, we aimed to study the status of transient thyrotoxicosis after PTX for SHPT patients with ESRD and normal thyroid function.

Methods

A total of 24 SHPT patients with preoperative normal thyroid function, normal thyroglobulin (Tg) and normal thyroid antibodies receiving PTX were enrolled from the Department of Endocrine and Breast Surgery, the First Affiliated Hospital of Chongqing Medical University, from January 2017 to January 2019. Tg, high sensitivity thyrotropin stimulating hormone (sTSH), triiodothyronine (T3), free triiodothyronine (fT3), thyroxine (T4) and free thyroxine (fT4) were evaluated the day before PTX and on day 1, 3 and 5 after PTX. Besides, all enrolled patients were evaluated whether there are symptoms associated with thyrotoxicosis.

Results

Among the 24 SHPT patients, 1 case (4.2%), 8 cases (33.3%) and 13 cases (54.2%) had suffered thyrotoxicosis at the first, third and fifth day after surgery, respectively. Serum FT4 level increased significantly from pre-operation (0.68 ± 0.15 ng/dl, normal range 0.59–1.25 ng/dl) to the third day after operation (1.91 ± 0.97 ng/dl, p<0.001) and then gradually decline. The frequencies of serum sTSH lower than the normal level gradually increased from the first day (8.3%) to fifth day (66.7%) after surgery.

Conclusion

Transient thyrotoxicosis is a common postoperative complication of parathyroidectomy for SHPT patients with ESRD and normal thyroid function, and it is necessary for clinicians to evaluate the perioperative thyroid function to make early diagnosis and appropriate prevention and treatment of thyrotoxicosis.

Transient Hyperthyroidism Induced by Thyroid Ultrasound

OBJECTIVES

Transient hyperthyroidism has been documented following surgical manipulation or direct trauma to the normal thyroid gland. This has best been studied in patients following parathyroidectomy and also reported following trauma to the neck, strangulation, and vigorous palpation of the thyroid gland. It has not previously been reported following a thyroid ultrasound.

METHODS

We report the case of a 58-year-old euthyroid woman with a large nontoxic multinodular goiter who developed transient hyperthyroidism following an ultrasound of the thyroid gland. She was not treated with anti-thyroid medications.

RESULTS

Two weeks later, her free T3 and free T4 were normal, and 11 weeks after the ultrasound, all thyroid tests, including her TSH, were within the reference range.

CONCLUSIONS

We believe this is the first report of a euthyroid individual who developed hyperthyroidism caused by thyroid ultrasonography. We hypothesize that pressure from the ultrasound probe during the examination compressed her large nodules, releasing stored hormone.

Transient hyperthyroidism after surgery for secondary hyperparathyroidism: a common problem

Background

Postoperative hyperthyroidism occurs in approximately one third of patients following parathyroidectomy due to primary hyperparathyroidism (PHP), but has only rarely been described in secondary hyperparathyroidism (SHP). The frequency, course, and laboratory markers of postoperative hyperthyroidism in SHP remain unknown. Our purpose was to evaluate the frequency and the clinical course of postoperative hypcrthyroidism following surgery of SHP and to determine the diagnostic value of thyroglobulin in this setting.

Material and Methods

A total of 40 patients undergoing parathyroidectomy because of SHP were included in this study. Thyroid stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fl4), and thyroglobulin (Tg) were determined one day before and on day 1, 3, 5, 10, and 40 after surgery. At each of these visits patients were clinically evaluated for signs or symptoms of hyperthyroidism.

Results

Biochemical evidence of hyperthyroidism was evident in 77% of patients postoperatively despite of preoperatively normal serum levels. TSH dropped from 1.18 ± 0.06mU/L to 0.15 ± 0.07mU/L (p = 0.0015). Free triiodothyronine (fT3) and fT4 levels increased from 2.86 ± 0.02ng/L and 10.32 ± 0.13ng/L, respectively, to their maximum of 4.83 ± 0.17ng/L and 19.35 ± 0.58ng/L, respectively. Thyroglobulin levels rose from 3.8 ± 0.8ng/mL to 111.8 ± 45.3ng/mL (p < 0.001). At day 40 all thyroid related laboratory values were within normal range. Correlation analysis of postoperative values revealed significant correlations for lowest TSH (r = -0.32; p = 0.038), and highest fT3 (r = 0.55; p < 0.001) and fT4 levels (r = 0.67; p < 0.001) with Tg.

Conclusion

Transient hyperthyroidism is frequent after parathyroidectomy for SHP with Tg being a suitable marker. Awareness of this self-limiting disorder is important to avoid inappropriate and potentially harmful treatment.

Post-parathyroidectomy thyrotoxicosis and atrial flutter: a case for caution

Despite transient hyperthyroidism reportedly occurring in ∼30% of post-parathyroidectomy (PTX) patients with primary hyperparathyroidism, it has rarely been described in the internal medicine literature. It occurs within days of surgery, is usually clinically mild or silent, and typically spontaneously resolves within weeks. Patients can, however, unusually present with symptoms and signs of thyrotoxicosis, including arrhythmias. We report a case of a hemodialysis patient who developed self-limited hyperthyroidism after intra-operative thyroid manipulation and excision during PTX surgery for secondary hyperparathyroidism that failed medical management. The patient was symptomatic with agitation, restlessness and new-onset atrial flutter, which required electrical cardioversion and temporary beta blockade. It is important that clinicians be aware of this potential surgical complication, so as to not attribute manifestations to post-PTX divalent cation disorders (i.e. hungry bone syndrome), thereby allowing prompt diagnosis and treatment. Post-operative monitoring of thyroid function is warranted for at least some subsets of patients: individuals who undergo thyroid exploration and palpation as part of their surgery to localize the parathyroid glands, as well as those with underlying cardiac disease or who are otherwise at high risk from even mild states of hyperthyroidism.