The changing face of reoperative parathyroidectomy: a single-centre comparison of 147 parathyroid reoperations

IntroductionReoperative parathyroidectomy for persistent and recurrent primary hyperparathyroidism is dependent on radiology. This study aimed to compare outcomes in reoperative parathyroidectomy at a single centre using a combination of traditional and newer imaging studies.Materials and methodsRetrospective case note review of all reoperative parathyroidectomies for persistent and recurrent primary hyperparathyroidism over five years (June 2014 to June 2019; group A). Imaging modalities used and their positive predictive value, complications and cure rates were compared with a published dataset spanning the preceding nine years (group B).ResultsFrom over 2000 parathyroidectomies, 147 were reoperations (101 in group A and 46 in group B). Age and sex ratios were similar (56 vs 62 years; 77% vs 72% female). Ultrasound use remains high and shows better positive predictive value (76% vs 57 %). 99mTc-sestamibi use has declined (79% vs 91%) but the positive predictive value has improved (74% vs 53%). 4DCT use has almost doubled (61% vs 37%) with better positive predictive value (88% vs 75%). 18F-fluorocholine positron emission tomography-computed tomography and ultrasound-guided fine-needle aspiration for parathyroid hormone are novel modalities only available for group A. Both carried a positive predictive value of 100%. Venous sampling with or without angiography use has decreased (35% vs 39%) but maintains a high positive predictive value (86% vs 91%). Cure rates were similar (96% vs 100%). Group A had 5% permanent hypoparathyroidism, 1% permanent vocal cord palsy and 1% haematoma requiring reoperation. No complications for group B.ConclusionOptimal imaging is key to good cure rates in reoperative parathyroidectomy. High-quality, non-interventional imaging techniques have produced a shift in the preoperative algorithm without compromising outcomes.     

Lung bullae and pulmonary fibrosis associated with marijuana smoking

A 26‐year‐old man with a history of heavy marijuana and minimal tobacco use was found to have extensive bilateral lung bullae and interstitial fibrosis, heavily infiltrated by pigmented macrophages. These features can be associated with marijuana smoking. The differential diagnoses in this patient are also discussed.     

Native and recombinant bovine growth hormone antagonize insulin action in cultured bovine adipose tissue

The current study was undertaken to determine if pituitary bovine GH (pbGH) and recombinant bGH (rbGH) antagonized insulin action in bovine adipose tissue after acute (2-h) and chronic (48-h) exposure and whether this was an intrinsic property of bGH. Insulin action (measured as the effect on incorporation of acetate-carbon into long-chain fatty acids) was unaffected by bGH in short term incubations regardless of whether hydrocortisone (HC) was present. After 48 h of culture, however, both pbGH and rbGH similarly antagonized the ability of insulin to maintain lipogenic capacity. This antagonism was dependent upon the presence of HC and was dose dependent, with half-maximal inhibition of insulin action occurring at about 0.5 ng/ml bGH. Bovine PRL did not mimic the effects of bGH on insulin action. These results establish that bGH antagonizes insulin action in bovine adipose tissue and that this effect is dependent upon long term exposure and the inclusion of HC in the culture medium. The fact that both rbGH and pbGH acted similarly indicates that this is an intrinsic property of bGH. The effect of bGH on insulin-dependent maintenance of lipogenic capacity may play an important role in redirecting nutrients away from adipose tissue to other tissues, such as muscle or mammary tissue. It is speculated that this metabolic effect of bGH plays an important role in the adaptive response to chronic bGH treatment, which increases milk yield of dairy cows and growth performance of beef cattle.