High prevalence of abdominal aortic calcification in patients with primary hyperparathyroidism as evaluated by Kauppila score

OBJECTIVE

The prevalence of abdominal aortic calcification (AAC) in primary hyperparathyroidism (PHPT) is unknown. We assessed both prevalence and severity of AAC in PHPT postmenopausal women.

METHODS

In this study 70 PHPT postmenopausal women and 70 age- and sex-matched controls were enrolled. Each participant underwent biochemical evaluation, lateral spine radiograph, bone mineral density (BMD) measurement (lumbar, femoral, radial sites), and kidney ultrasound. Lateral lumbar films were analyzed in the region of L1-L4 vertebrae and the Kauppila score (a semi-quantitative grading system) was used to assess the severity of AAC.

RESULTS

There were no differences regarding demographic and cardiovascular risk factors in the two groups. PHPT patients had higher prevalence of kidney stones (30% vs 7%, P=0.0008) and lower radial BMD values (0.558±0.071 vs 0.588±0.082 g/cm(2), P<0.05) compared with controls. PHPT patients showed higher prevalence of AAC (31 vs 18, P=0.03), with more severe calcifications (Kauppila score 7.35±6.1 vs 5.05±3.5, P=0.007). PHPT patients with AAC were older and had been suffering from the disease for a longer period compared with those without ACC. Moreover, PHPT patients with severe AAC had mean higher serum parathyroid hormone levels compared with patients with moderate or mild calcifications. In PHPT patients with AAC, multiple regression analysis, adjusted for age and years since diagnosis, showed that only parathyroid hormone significantly correlated with Kauppila score.

CONCLUSION

We found a higher prevalence and severity of AAC in PHPT related to parathyroid hormone effect.

Six-year follow-up of a characteristic osteolytic lesion in a patient with tumor-induced osteomalacia

OBJECTIVE

Tumor-induced osteomalacia is a rare paraneoplastic syndrome characterized by hypophosphatemia and inappropriately normal or low 1,25-dihydroxyvitamin D.

CLINICAL CASE

Here, we report a 6-year postoperative follow-up of a patient with oncogenic osteomalacia with a distinctive skeletal manifestation. The latter was characterized by an almost linear lytic lesion of a few millimeters with irregular borders, mainly involving the trabecular compartment but extending into cortical shell, located in the middle third of the right fibula. Six years after tumor resection, a sclerotic repair with a complete recovery was observed. Furthermore, we monitored a striking increase in bone mineral density throughout the observation period, reaching a peak of 73% over basal values at lumbar spine after 2 years; at total femur and radius, the peak was 47.5 and 4.6% respectively, after 4 years from tumor resection.

CONCLUSIONS

We report for the first time that an osteolytic lesion may be part of the skeletal involvement in tumor-induced osteomalacia.

Sporadic and hereditary primary hyperparathyroidism

Primary hyperparathyroidism (PHPT) is a common endocrine disorder, particularly frequent in post-menopausal women. It is characterized by hypercalcemia with inappropriately high spontaneous plasma PTH. Singlegland adenoma is the most common cause (75- 85%). PHPT is usually a sporadic disease but in approximately <5% of cases, a familial hyperparathyroid syndrome is diagnosed. Familial hyperparathyroidism is a clinically and genetically heterogeneous group of disorders including: multiple endocrine neoplasia (MEN) type 1, MEN type 2A, MEN4, benign familial hypocalciuric hypercalcemia, neonatal severe hyperparathyroidism, hyperparathyroidism-jaw tumor syndrome, and familial isolated hyperparathyroidism. These syndromes show mendelian inheritance patterns and the main genes for most of them have been defined. The classic form of PHPT, which presents with hypercalcemia, kidney stones, and bone disease, is no longer common. Currently, there is an increasing interest in the subtle manifestations of PHPT, particularly the cardiovascular and neuropsychiatric manifestations. Parathyroidectomy is the definitive cure for PHPT even though patients with the asymptomatic form of the disease can be followed conservatively.

Self-injection of diazepam in naive rats: effects of dose, schedule and blockade of different receptors

The present series of experiments had two main objectives: The first was to determine the conditions under which self-injection of the benzodiazepine diazepam would be optimal; the second was to identify neurochemical substrates which underlie the maintenance of diazepam self-administration. Data from the first experiment indicated that rats maintained on an FI-1 (Fixed Interval of 1 min) schedule of food delivery self-injected significantly more diazepam than rats not maintained on this schedule. Results from the second experiment demonstrated that the benzodiazepine antagonist Ro 15-1788, and the GABA antagonist bicuculline, significantly reduced diazepam self-administration, but the opiate antagonist naloxone was without effect. Data from the third experiment showed that the dopamine antagonist haloperidol also significantly reduced the rate of diazepam self-injection. Thus, these findings indicate that the acquisition of diazepam self-injection occurs under an FI-1 schedule of food delivery, which has been shown to be middly stressful, while its maintenance depends upon the functional integrity of benzodiazepine and GABA receptors and upon the activity of dopaminergic pathways.

The suppression of ethanol self injection by buprenorphine

The schedule induced self-injection procedure was used to establish ethanol self-injection in 16 rats. Pretreatment with an injection of 0.3 mg/kg buprenorphine significantly reduced ethanol self-injection in a group of 8 rats. This effect was not found in a second group of 8 rats which received saline pretreatment. The findings provide support for an involvement of buprenorphine, in ethanol self-injection, which cannot be explained in terms of opiate induced shifts in taste preference. From the present data it cannot be determined whether the agonist or antagonist opiate properties of buprenorphine cause the blocking effect.