Osteitis fibrosa cystica (OFC) and Brown Tumour are two related but distinct types of bone lesions that result from overactivity of osteoclasts most often associated with chronic kidney disease (CKD). Despite their potential consequences, these conditions are poorly understood because of their rare prevalence and variability in their clinical manifestation. Canonically, OFC and Brown Tumours are caused by secondary hyperparathyroidism in CKD. Recent literature showed that multiple factors such as hyperactivation of the renin-angiotensin-aldosterone system and chronic inflammation may also contribute to the occurrence of these diseases through osteoclast activation. Moreover, hotspot KRAS mutations were identified in these lesions placing them in the spectrum of RAS-MAPK-driven neoplasms, while until recently thought to be reactive lesions. Some risk factors contributed to the occurrence of OFC and Brown Tumour such as age, gender, comorbidities, and certain medications. The diagnosis of OFC and Brown Tumour includes clinical symptoms involving chronic bone pain and laboratory finding of hyperparathyroidism. In radiological imaging, the X-ray and Computed tomography (CT) scan could show lytic or multi-lobular cystic alterations. Histologically both lesions are characterized by clustered osteoclast in a fibrotic hemorrhagic background. Based on the latest understanding of the mechanism of OFC, this review elaborates on the manifestation, diagnosis, and available therapies that can be leveraged to prevent the occurrence of OFC and Brown Tumour.

The frequency of concurrent thyroid cancer in patients with primary hyperparathyroidism (pHPT) varies. While the pathological association between thyroid and parathyroid disorders is frequently noted, the co-occurrence of parathyroid adenoma and papillary thyroid cancer is exceptionally rare. Furthermore, the occurrence of an ectopic parathyroid adenoma in the retropharyngeal space is exceedingly rare. Ectopic parathyroid glands present considerable complexities in both diagnosis and surgical management, especially within the realm of surgical intervention. The potential inability to accurately identify and excise ectopic parathyroid adenomas during the initial surgery may lead to an increased morbidity and recurrence, requiring high-risk reoperations. Therfore, the evaluation of anatomical variations through the utilization of relevant diagnostic tools plays a crucial role in guiding decisions pertaining to clinical manifestations, diagnostic methods, surgical interventions, and operative strategies for parathyroid tumors. We present the case of a 51-year-old female patient with papillary thyroid carcinoma in the right thyroid lobe and an ectopic parathyroid adenoma in the retropharyngeal space confirmed through surgical intervention. This case sheds light on the unusual occurrence of an ectopic parathyroid adenoma in the retropharyngeal region within a thyroid cancer patient, providing valuable insights within the realm of thyroid malignancies.

Introduction: The coronary flow reserve (CFR) is a sign of early-stage coronary artery disease (CAD). Plasma atherogenic index (PAI) is related to atherosclerosis and cardiovascular mortality. Therefore, our aim was to determine CFR and PAI in patients with primary hyperparathyroidism (PHPT) and investigate whether PAI can be used in the detection of early-stage CAD. Material and Methods: The sample was comprised of 44 patients with PTHT and 33 healthy volunteers. We defined CFR as the ratio of the hyperemic diastolic peak velocity to the baseline diastolic peak velocity. PAI values were calculated with the formula of log 10 triglyceride (TRG) / high-density lipoprotein (HDL). Result: The comparison of the groups for PAI and CFR demonstrated that PAI levels were significantly higher while CFR levels were significantly lower in the PTHT patients (p<0.01, p=0.01, respectively). The correlation analysis revealed that CFR was negatively correlated with PAI and TRG (PAI- p<0.0001 r=-0.537).The multivariate logistic regression analysis showed that only a high PAI level (OR: 151.6, 95% confidence interval (CI): 4.1-5480, p=0.006) was an independent predictor of reduction in CFR in PHPT patients. Conclusion: Overall, we found an independent correlation between PAI and CFR values. Hence, PAI may be useful in identifying PHPT patients facing a high risk of adverse cardiovascular events and may also allow early diagnosis of subclinical atherosclerosis.

Background: Parathyroid imaging techniques are used in patients with biochemically confirmed primary hyperparathyroidism (pHPT) to detect the localization of enlarged parathyroid gland(s) (PTG) and thereby to allow more focused, unilateral or minimally invasive parathyreoidectomy (PTX), instead of classical bilateral neck exploration (BNE). Although the preferred sequence of imaging continues to evolve, ultrasonography (US) is usually the first line modality, followed by 99mTc sestamibi parathyroid scan (SPS). However, both tests may have suboptimal localizing accuracy with considerable rate of non-localized cases. Therefore, more accurate four-dimensional computed tomography scan (4D-CT) has been employed for PTG imaging. Currently, there is a paucity of data evaluating the utility of 4D-CT in low case-load settings. Aim: To evaluate the impact of PTG imaging, using 4D-CT in conjunction with it’s intraoperatively displayed results, on the outcomes of surgical PTX. Our primary outcome was sensitivity of 4D-CT in comparison to US and SPS for preoperative PTG adenoma localization. The secondary outcomes were the need for redo surgery and morbidity. Additionally, the characteristics of surgical PTX, i.e. operative time, number of removed parathyroid glands, and rate of simultaneous thyroid surgery, were assessed. Methods: A single-center retrospective analysis of surgically treated patients with pHPT from 01/2010 to 01/2021 was conducted. Evaluation of impact of the preoperative imaging modalities on the results of surgical treatment was carried out. Results: During the study period 290 PTX were performed, 45 cases were excluded due to surgery for secondary, tertiary or recurrent HPT, or due to use of alternative imaging techniques; the remaining 245 patients were included in the study. US was carried out for PTG imaging in 236 (96.3%), SPS in 93 (38.0%), and 4D-CT in 52 patients (21.2%). The use of 4D-CT was associated with a significantly higher rate of successful localization of enlarged PTG (49 cases, 94.2%) compared to US and SPS (74 cases, 31.4%, and 54 cases, 58.1%, respectively). We distinguished between three groups of patients based on preoperative imaging: 1) PTG lateralization via US or SPS in 106 (43.3%) cases, 2) precise localization of PTG via 4D-CT in 49 (20.0%) patients, and 3) in 90 cases (36.7%) PTG imaging failed to localize enlarged gland. The group of 4D-CT localization had significantly shorter operative time, lower rate of simultaneous thyroid resections, as well as lower rate of removal of ≥2 PTG, compared to the other groups. The 4D-CT imaging was also associated with the lowest perioperative morbidity and with the lowest median PTH in one month follow-up; however, compared to the other groups, these differences were statistically not significant. Implementation of 4D-CT (since 01/2018) decreased the need for redo surgery (from 11.5% to 7.3%), and significantly increased the annual case load of PTX at our institution (from 15.3 to 41.0), compared to the period before 4D-CT diagnostics. Conclusions: 4D-CT imaging enabled to precisely locate almost 95% of enlarged PTG in patients with pHPT. Accurate localization and intraoperatively displayed imaging results are useful guides for surgeons in making PTX a faster and safer procedure in a low volume center.

Adult X-linked hypophosphatemia (XLH) patients present with specific symptoms, including enthesopathies (e.g., ossification of the longitudinal ligament (OPLL), osteophytes around the large joint, and enthesopathy in the Achilles tendon), the development of severe secondary and tertiary hyperparathyroidism (SHPT/THPT) and the subsequent progression of chronic kidney disease (CKD). In addition, these patients exhibit the typical phenotypes of osteomalacia, such as pseudofracture and fracture in weight-bearing bones, odontitis, and tooth abscess. The mechanism underlying enthesopathy development is unknown; however, a common underlying mechanism among XLH and autosomal recessive hypophosphatemic rickets, ARHR1.2, due to mutations in PHEX, DMP1, and ENPP1, is assumed. Clarification of the pathogenesis and drug discovery for this complication is an urgent issue to address, as many adult XLH patients suffer subsequent debilitating nervus symptoms or impingement syndrome, and existing treatments are ineffective. Severe SHPT and THPT are associated with conventional therapy, including active vitamin D and phosphate supplementation, and complicated and careful adjustment of the dosage by experienced clinicians is required to avoid SHPT/THPT. Burosumab is a very effective therapy without risk for the development of SHPT/THPT. However, the indication of this drug should be carefully considered along with the cost-effectiveness, guidelines or recommendations and health care system of each country.