Does Preoperative 25-Hydroxyvitamin D Status Significantly Affect the Calcium Kinetics after Total Thyroidectomy?

Background

Although previous studies have suggested that low preoperative 25-hydroxyvitamin D (25-OHD) is a risk factor for hypocalcemia after total thyroidectomy, the impact of preoperative 25-OHD on calcium (Ca)/parathyroid hormone (PTH) kinetics in the immediate postoperative period remains unclear. The study compared the postoperative Ca/PTH kinetics between different preoperative 25-OHD levels.

Patients

A total of 281 patients who underwent a total thyroidectomy were analyzed. Serum Ca was measured preoperatively within 1 h after surgery (Ca-D0) and on the following morning (Ca-D1). Preoperative 25-OHD was also measured after overnight fasting while postoperative PTH was checked at skin closure on day 0 (PTH-D0) and on the following morning on day 1 (PTH-D1). The Ca/PTH kinetics were compared between three groups (group I: preoperative 25-OHD < 10 ng/mL; group II: 25-OHD = 10–20 ng/mL; group III: 25-OHD > 20 ng/mL).

Results

Group I had significantly lower preoperative Ca (p = 0.016) and Ca-D0 (p = 0.036) but higher PTH-D1 (p = 0.015) than groups II and III. PTH-D0, Ca-D1, and the rate of clinically significant hypocalcemia were similar in the three groups. Group I had a significantly smaller Ca drop (?0.02 vs. 0.01 and 0.02 mmol/L, p = 0.011) and a tendency for a significantly smaller PTH drop (0.4 vs. 0.5 and 1.0 pmol/L, p = 0.073) than groups II and III. PTH-D1 (OR = 1.550) and 25-OHD (OR = 0.958) were independent factors for Ca drop from day 0 to day 1.

Conclusions

Although group I began with lower serum Ca, those patients tended to have a greater PTH response to Ca drop and so preoperative 25-OHD did not significantly affect the overall Ca kinetics from preoperative to day 1.     

How Useful Are Perioperative Biochemical Parameters in Predicting the Duration of Calcium and/or Vitamin D Supplementation After Total Thyroidectomy?

Background

Oral calcium and calcitriol are often prescribed after total thyroidectomy to avoid biochemical and/or symptomatic hypocalcemia. We aimed to identify independent perioperative factors that correlated with the duration of calcium and/or calcitriol supplementation after total thyroidectomy.

Methods

Of 271 eligible patients, 48 (17.7 %) required calcium and/or calcitriol supplements on discharge. Patients were gradually weaned from the supplementation by one surgeon according to a biweekly algorithm based on serum calcium (Ca). Duration of supplementation was calculated from the date of operation to the date of ceasing all supplementation without biochemical hypocalcemia (i.e., serum adjusted Ca ≥8.44 mg/dL). The Cox regression analysis was performed to identify independent perioperative factors for duration of supplementation. The best cut-off value for these independent factors was determined by the receiver characteristic curve.

Results

In the multivariate analysis, parathyroid hormone (PTH) at skin closure (PTH-SC) (RR 1.742, 95 % CI 1.080–2.810) and on postoperative day 1 adjusted Ca (Ca-D1) (RR 77.526, 95 % CI 3.600–1669.57) were the only two independent determinants for shorter duration before ceasing all supplementation. The best cut-off values in predicting supplementation ≥6 months for PTH-SC and Ca-D1 were 7.08 pg/mL (sensitivity = 100 %, specificity = 60.5 %, PPV = 40.0 % and NPV = 100 %) and 7.88 mg/dL (sensitivity = 90.0 %, specificity = 55.3 %, PPV = 34.6 % and NPV = 95.5 %), respectively.

Conclusions

Both PTH-SC and Ca-D1 were independently associated with the duration of supplementation after total thyroidectomy. Almost all patients with PTH-SC ≥7.08 pg/mL or Ca-D1 ≥7.88 mg/dL did not require supplementation ≥6 months whereas about one third of patients with PTH-SC <7.08 pg/mL or Ca-D1 <7.88 mg/dL required supplementation ≥6 months.     

Postablation Stimulated Thyroglobulin Level is an Important Predictor of Biochemical Complete Remission after Reoperative Cervical Neck Dissection in Persistent/Recurrent Papillary Thyroid Carcinoma

Background

The efficacy of reoperative cervical neck dissection (RND) in achieving biochemical complete remission (BCR) (or postreoperation stimulated thyroglobulin [sTg] of <0.5 ng/mL) remains unclear in persistent/recurrent papillary thyroid carcinoma (PTC). We hypothesized that lower postablation sTg levels would indicate a higher rate of BCR after RND. Our study examined the association between postablation sTg and BCR after one or more RNDs.

Methods

Of 199 patients who underwent RND, 81 patients were eligible. The postablation sTg levels (≤2 and >2 ng/mL) were correlated with the postreoperation sTg levels after RNDs. Patients’ clinicopathological characteristics, operative findings, and subsequent RNDs were compared between those with BCR after RNDs and those without.

Results

Those with postablation sTg levels of ≤2 ng/mL had significantly higher BCR rate after the first RND (77.8 vs. 5.6 %, p < 0.001), overall BCR after one or more RNDs (77.8 vs. 9.3 %, p < 0.001), and better 5-year recurrence-free survival after the first RND (80.0 vs. 60.1 %, p = 0.049) than those with postablation sTg levels of >2 ng/mL. Overall BCR gradually decreased after each subsequent RND. Postablation sTg significantly correlated with postreoperation sTg (ρ = 0.509, p < 0.001). After adjusting for the number of metastatic lymph nodes excised at first RND and presence of extranodal extension, postablation sTg of ≤ 0.2 ng/mL was the only independent factor for BCR after one or more RNDs (odds ratio 37.0, 95 % confidence interval 5.68–250.0, p = 0.001).

Conclusions

Only a third of patients who underwent one or more RNDs for persistent/recurrent PTC had BCR afterward. Postablation sTg level was an independent factor for BCR. Completeness of the initial operation is important for the subsequent success of RND.     

CT‐guided aspiration cytology of advanced silicosis and confirmation of the deposited zeolite nano particles through X ray diffraction: A novel approach

Silicosis is a common occupational lung disease, resulting in fibrotic nodular lesions in the upper lobes of the lung parenchyma. Most of the pneumoconioses are diagnosed on the basis of relevant history and clinico‐radiological correlation. Image‐guided aspiration cytology appears to be poorly yielding and is not usually considered as a diagnostic modality. However, silicosis may sometimes offer a diagnostic challenge because of its radiological resemblance and clinical overlap with pulmonary tuberculosis and neoplastic lesions. We present a unique situation where image‐guided fine needle aspiration cytology (FNAC) has been advised on the basis of nodular upper lobe opacities. The cytology smears revealed hypocellular granular material, while phase contrast and polarized light microscopy highlighted crystalline particles. History of silica dust exposure long back was available after the cytological evaluation, suggesting the diagnosis of pulmonary silicosis. X ray diffraction (XRD) crystallography was also possible on cytology smears, confirming zeolite nano particles of size as small as 40 ? 50 nm as the concerned agent for the first time. Cytological evaluation by phase contrast and polarized light microscopy may be useful for the confirmation of silicosis, supplemented by clinical history and radiological evaluation. XRD on smears may help in determination of chemical nature and particle size. Diagn. Cytopathol. 2016;44:246–249. © 2015 Wiley Periodicals, Inc.     

Evaluating the Incidence, Clinical Significance and Predictors for Vocal Cord Palsy and Incidental Laryngopharyngeal Conditions before Elective Thyroidectomy: Is There a Case for Routine Laryngoscopic Examination?

Background

Routine preoperative laryngeal examination remains controversial. We aimed to assess the utility of preoperative routine flexible laryngoscopy (FL) by looking at the incidence, clinical significance and predictors for preoperative vocal cord paresis (VCP) and incidental laryngopharyngeal conditions (LPC) in our consecutive cohort.

Methods

A total of 302 patients underwent laryngeal examination by an independent otorhinolaryngologist and were specifically asked about voice/swallowing symptoms suggestive of VCP 1 day before surgery. As well as vocal cord (VC) mobility, the naso-pharynx and larynx were examined using FL. Any VCP and/or LPC was recorded. VCP was defined as reduced or absent movement in one or more VC. An LPC was considered clinically significant if the ensuing thyroidectomy was changed or deferred.

Results

Seven (2.3 %) patients had preoperative VCP, while an additional seven patients had an incidental LPC. Of the seven VCPs, five were caused by previous thyroidectomy, while two were caused by a benign goitre. The incidence of asymptomatic VCP in a previously non-operated cohort was 1/245 (0.41 %). Voice/swallowing symptoms (p = 0.033) and previous thyroidectomy (p < 0.001) were the two significant predictors for VCP. The seven incidental LPCs were vallecular cyst (n = 1), VC scar and polyp (n = 2), nasopharyngeal cyst and polyp (n = 3) and redundant arytenoid mucosa (n = 1); however, as they were benign, all seven patients proceeded to thyroidectomy as planned.

Conclusions

Given the low incidence (0.41 %) of asymptomatic VCP in a previously non-operated cohort and that none of the seven LPCs were considered clinically significant, routine preoperative laryngoscopic examination should be reserved for those with previous thyroidectomy and/or voice/swallowing symptoms.