Pre-operative evaluation of risk factors for complications in patients with primary hyperparathyroidism

Contemporary Management of Primary Hyperparathyroidism

Primary hyperparathyroidism can be asymptomatic or symptomatic, as well as classic, normocalcemic, or normohormonal. It is important to rule out other causes of hypercalcemia or hyperparathyroidism. Preoperative localization with imaging is necessary for a minimally invasive approach and can be helpful even if planning 4-gland exploration. There are a variety of intraoperative techniques that can assist with localization as well as confirming success. Standard of care remains surgical resection of affected glands. However, there are less invasive management strategies that can be considered for poor surgical candidates.

Immunomodulatory Potential of Diuretics

In this review, diuretics and their immunomodulatory functions are described. The effects on the immune response of this group of drugs are reported in patients suffering from hypertension and under experimental conditions involving animal models and cell line studies. The pathogenesis of hypertension is strongly connected to chronic inflammation. The vast majority of diuretics modulate the immune response, changing it in favor of the anti-inflammatory response, but depending on the drug, these effects may differ. This topic is significantly important in medical practice regarding the treatment of patients who have coexisting diseases with chronic inflammatory pathogenesis, including hypertension or chronic heart failure. In patients with metabolic syndrome, allergies, or autoimmune disorders, the anti-inflammatory effect is favorable, because of the overstimulation of their immune system. Otherwise, in the geriatric population, it is important to find the proper anti- and pro-inflammatory balance to avoid an enhancement of immune response suppression, which can result in reducing the risk of serious infections that can occur due to the age-diminished function of the immune system. This article is intended to facilitate the selection of an antihypertensive drug that depends on the patient's immune situation.

Primary hyperparathyroidism and hypertension

Although untreated primary hyperparathyroidism is associated with increased cardiovascular mortality, controversy exists regarding the therapeutic effects of parathyroidectomy on cardiovascular health. This review will examine the evidence linking primary hyperparathyroidism (PHPT) and cardiovascular disease, specifically hypertension, and evaluate the available literature regarding the natural history of hypertension after successful parathyroidectomy.

Impaired endothelial function in patients with mild primary hyperparathyroidism improves after parathyroidectomy

BACKGROUND

Primary hyperparathyroidism (PHPT) is associated with cardiovascular morbidity; however, data on the reversibility of cardiovascular disease in mild primary hyperparathyroidism are conflicting. The aim of this study was to assess endothelial function in patients with mild PHPT before and after parathyroidectomy (Ptx).

METHODS

We prospectively evaluated 53 patients with mild PHPT (Group 1; 45 women, eight men; aged 52 ± 3·1 years) and 46 healthy control subjects (Group 2; 38 women, eight men; aged 46 ± 9·5 years). Endothelial function was measured as flow-mediated dilation (FMD) and carotid intima-media thickness (CIMT) using Doppler ultrasonography. Patients with diabetes mellitus, coronary heart disease, impaired renal function, hyperthyroidism, hypothyroidism and a history of smoking were excluded from the study. Patients were studied at baseline and 6-12 months after the first evaluation.

RESULTS

There were no differences with respect to age, gender and BMI between the two groups. Hypertension prevalence was three times higher in group 1 than in controls. % FMD was lower in group 1 than in group 2 (2·6 ± 1·2 vs 14·8 ± 9·6, P < 0·001). CIMT was higher in patients with PHPT than controls (0·69 ± 0·18 vs 0·61 ± 0·12, P = 0·045). This significance remained when hypertensive patients were excluded from the analysis. While FMD and CIMT improved significantly after Ptx, there were no differences in mild PHPT patients who followed without parathyroidectomy.

CONCLUSION

FMD and CIMT are impaired in patients with mild PHPT compared to controls and improved significantly after a successful Ptx. Ptx improves endothelial function in patients with mild PHPT that may lead to decreased cardiovascular morbidity and mortality.

Monitoring endocrine function

This article reviews current knowledge concerning the monitoring of endocrine function in patients in the clinical setting. Monitoring techniques are discussed and literature is reviewed regarding diabetes mellitus, thyroid, and parathyroid disorders, pheochromocytoma, adrenal insufficiency, and carcinoid tumors.

Growth hormone and insulin-like growth factor binding protein-1 responses to oral glucose in patients with primary hyperparathyroidism

BACKGROUND

GH and IGFBP-1 both play a role in glucose homeostasis.

OBJECTIVE

To assess the GH and IGFBP-1 responses to an oral glucose load and their relationship with glucose homeostasis in patients with primary hyperparathyroidism.

DESIGN

A cross-sectional study with a control group followed by a longitudinal study after parathyroidectomy.

PATIENTS AND METHODS

We studied 15 patients with primary hyperparathyroidism (eight women, aged 59.6 +/- 2.2 years) and nine healthy normocalcaemic controls. All subjects were ambulatory and were studied as outpatients. Glucose, insulin, GH and IGFBP-1 were measured during an oral glucose (75 g) tolerance test (OGTT).

RESULTS

Patients with hyperparathyroidism showed similar glucose responses to OGTT to those found in controls. Insulin responses were higher in patients (peak insulin 96.33 +/- 9.71 mU/l) in relation to values found in controls (58.11 +/- 9.03 mU/l; P < 0.01). Suppression of GH levels after OGTT was more marked in patients [nadir 0.03 (0.02-0.05) microg/l] than in normocalcaemic subjects [nadir GH 0.12 (0.08-0.42) microg/l; P = 0.002]. However, baseline IGFBP-1 concentration and its decrease after glucose load were similar in patients and controls. Normalization of calcium levels after parathyroidectomy was not followed by any significant changes in glucose, insulin and GH responses to OGTT. The minimum concentration of IGFBP-1 and the area under the curve (AUC) of IGFBP-1 after OGTT were higher after parathyroidectomy (3.34 +/- 0.69 microg/l and 8.94 +/- 1.72 microg x h/l, respectively) than at diagnosis (2.19 +/- 0.42 microg/l and 6.74 +/- 1.28 microg x h/l, respectively; P < 0.05). No correlation was found between PTH, calcium and phosphorus concentrations and GH and IGFBP-1 values in patients before or after normalization of calcium metabolism.

CONCLUSION

GH and IGFBP-1 do not seem to be directly involved in the hyperparathyroidism-associated changes in carbohydrate metabolism. The postoperative changes in the depression of IGFBP-1 after OGTT remain to be elucidated.