Comparing ultrasound assessment of thyroid nodules using BTA U classification and ACR TIRADS measured against histopathological diagnosis.

INTRODUCTION: The British Thyroid Association (BTA) recommends ultrasound assessment of thyroid nodules using the U classification. The American College of Radiologists (ACR) recommend assessment with the Thyroid Imaging Reporting and Data System (TIRADS). We conduct the first UK study to compare these two systems. METHODS: Ultrasound (US) reports of patients who underwent surgical excision of thyroid nodules over a 10-year period in one UK centre were reviewed. US findings were collected, and the classifications were retrospectively applied. The systems were compared to histopathological diagnosis. RESULTS: 308 nodules in 296 patients are included. 135 nodules (43.8%) were malignant. U classification showed sensitivity of 88.1% in recommending FNA, significantly higher than TIRADS at 73.3% (p = .0002). The U classification showed specificity of 41.6%, significantly lower than TIRADS at 64.2% (p=<0.0001). PPV between classifications at equivalent levels showed no significant difference at U3/TR-3 (p=.81), U4/TR-4 (p=.30) or U5/TR-5 (p=.90). DISCUSSION: Classification systems enable risk stratification of potentially malignant thyroid nodules. This study shows BTA U classification has a higher sensitivity but lower specificity than TIRADS.

The effect of radioiodine treatment on the diseased thyroid gland.

Purpose: Radioiodine (I131) therapy is the treatment mainstay for several benign and malignant thyroid disorders, however I131 is known to cause DNA damage and liberation of thyroidal self-antigens inducing secondary immunoreactivity. The exact mechanisms underpinning cellular death and subsequent induction of autoimmune thyroid disease following I131 treatment have not yet been fully elucidated. This manuscript aims to review the literature concerning the effects of I131 on the thyroid gland.Conclusion: The effects of I131 on malignant thyroid cells appears to depend on absorbed dose with the literature demonstrating a clear initial delay in the triggering of apoptosis in response to I131-mediated cellular damage. Some studies also observed necrotic cellular death following high-dose I131 treatment. Liberation of thyroidal self-antigen following I131 treatment helps to explain phenomena such as the subsequent induction of autoimmune thyroid disease. The clinical utility of cytokines and autoantibodies for prognostication of hypothyroidism and treatment failure following I131 remains uncertain and further appropriately-powered studies are required to clarify their role. The potential role of other cell death mechanisms activated after treatment with I131 should also be explored in order to fully delineate the thyroidal response.

Parathyroid surgery: from inception to the modern day.

Parathyroid surgery has undergone great changes since its inception less than a century ago. It is still the only definitive option available to cure primary or tertiary hyperparathyroidism. This review details the development of parathyroid surgery, our understanding of hyperparathyroidism and the treatment options available. It also discusses the technological advances that have enabled parathyroid localization and prediction of surgical success.

Predicting thyroxine requirements following total thyroidectomy.

OBJECTIVE: Optimal thyroxine replacement following total thyroidectomy is critical to avoid symptoms of hypothyroidism. The aim of this study was to determine the best formula to determine the initiated replacement dose of levothyroxine immediately following total thyroidectomy. DESIGN: Prospective study. All patients were initiated on 100 µg levothyroxine and titrated to within the reference range for TSH and free T4. Correlations to height, weight, age, lean body mass (LBM), body surface area (BSA) and body mass index (BMI) were calculated. PATIENTS: One hundred consecutive adult patients underwent total thyroidectomy for non-malignant disease. MEASUREMENTS: Comparison between three methods of levothyroxine dose prediction, aiming for a levothyroxine dose correct to within 25 µg of actual dose required. RESULTS: Correlations were seen between levothyroxine dose and patient age (r=-0.346, P<0.01), bodyweight (r=0.296, P<0.01), LBM (r=0.312, P<0.01), BSA (r=0.319, P<0.01) and BMI (r=0.172, P<0.05). A regression equation was calculated (predicted levothyroxine dose=[0·943 × bodyweight] + [-1.165 × age] + 125.8), simplified to (levothyroxine dose= bodyweight - age + 125) pragmatically. Initiating patients empirically on 100 µg post-operatively showed that 40% of patients achieved target within 25 µg of their required dose; this increased to 59% when using a weight-only dose calculation (1.6 µg/kg) and to 72% using the simplified regression equation. CONCLUSIONS: A simple calculated regression equation gives a more accurate prediction of initiated levothyroxine dose following total thyroidectomy, reducing the need for outpatient attendance for dose titration.

Intraoperative parathyroid hormone monitoring to determine long-term success of total parathyroidectomy for secondary hyperparathyroidism.

BACKGROUND: Use of intraoperative parathyroid hormone (ioPTH) monitoring during total parathyroidectomy for secondary hyperparathyroidism is common, although its ability to predict long-term normoparathyroid state is not known. METHODS: Prospective evaluation of 57 consecutive patients undergoing total parathyroidectomy for renal hyperparathyroidism with ioPTH monitoring and follow-up PTH assays were used to categorize the patients into 3 groups: success, adequate biochemical control, and failure. RESULTS: There was no statistically significant difference in percentage reduction of ioPTH between the 3 groups (p = .07), although there was a moderate negative correlation between percentage reduction of ioPTH and percentage reduction of PTH at follow-up (R = 0.57). CONCLUSIONS: When used under current guidelines, ioPTH monitoring is of no use in predicting long-term cure for these patients because it does not predict success. Patients that undergo total parathyroidectomy are required to have long-term calcium and PTH assay follow-up because normoparathyroidism cannot be assumed. Using the regression equation calculated, success may be predicted for future patients.

Inhibition of rhinovirus replication in vitro and in vivo by acid-buffered saline.

Human rhinoviruses (HRVs) are quite sensitive to low pH. To determine whether this characteristic might be a therapeutic target, we evaluated the sensitivity of HRV to low-pH buffers in vitro and in vivo. Our findings confirm that low pH inhibited replication of most HRVs and reduced the replication of influenza virus. Preliminary experiments verified that the surface pH of the human nasopharynx could be transiently lowered to pH approximately 4.0 by topical administration of citrate/phosphate (CP) buffers, which was well tolerated. In a pilot experimental colds study, intranasal administration of CP buffer, compared with normal saline, reduced viral shedding by 1 log unit (10(3) vs. 10(4) 50% tissue culture infective dose/mL; P<.01), although respiratory symptoms were not significantly reduced. These findings demonstrate that low-pH buffers have antiviral activity in vivo and suggest that a larger clinical trial is warranted to determine whether this approach could reduce rates of viral transmission.