Primary Hyperparathyroidism

https://doi.org/10.1016/j.otc.2010.01.009Get rights and content

Section snippets

Pathology and etiology

PHPT is the third most common endocrine disorder and the most common cause of hypercalcemia in the outpatient setting.5, 7 It is defined as hypercalcemia secondary to overproduction of PTH by one or more parathyroid glands. Normally, increased calcium levels suppress the production of PTH because of a negative feedback mechanism.7, 8 Parathyroid glands detect small changes in serum calcium through the calcium sensing receptor, which results in significant changes in PTH secretion. The goal of

Presentation and diagnosis

Over the last 30 years, a shift has occurred in the presentation of PHPT. Historically, patients presented with clinical findings related to long-standing disease, such as nephrolithiasis, brown tumors, osteitis fibrosa cystic, and muscle atrophy.1 With the advent of routine serum calcium measurements, patients present with hypercalcemia much earlier and subsequently have fewer, if any, overt symptoms. Up to 80% of patients have been described as asymptomatic; however, many studies have shown

IOPTH

PTH is an 84 amino acid peptide hormone produced by the parathyroid glands. PTH first is synthesized as a preproparathyroid hormone with 155 amino acids, and after cleavage of a 25 amino acid sequence and a 6 amino acid sequence, it is converted to intact PTH, an 84 amino acid hormone.31 Intact PTH has a half-life of less than 5 minutes with most of its metabolism in the liver and the remainder in the kidney. Intact PTH assays detect 1-84 PTH and large c-terminal fragments, which can alter PTH

Surgical options

Traditionally, parathyroid surgery involved a BNE and identification of all parathyroids before removal of the abnormal gland or glands. With the advent of both improved preoperative localization studies and IOPTH, MIP surgery has emerged as the new standard for most surgeons worldwide.38 There are several types of MIP surgery based on the size of incision and use of endoscopy. A UNE uses a standard Kocher incision toward the side of the localized gland, and BNE is not done unless the gland

Persistent and recurrent PHPT

Cure of PHPT is most readily achieved during initial neck exploration. Unfortunately, a subset of patients requires re-exploration for persistent or recurrent disease. Neck re-exploration is technically difficult because of distortion of neck anatomy by fibrosis and frequently obliterated normal tissue planes. Accordingly, reoperative surgery relative to de novo cases carries an increased risk of injury to RLNs and to normal residual parathyroid tissue. Pathologic hyperfunctioning parathyroid

Diagnostic approach

Recurrent disease is defined as redevelopment of PHPT more than 6 months after initial curative surgery. Between 1% and 6% of one-degree HPT patients experience persistent disease or develop a recurrence after initial resection.50 Accordingly, all patients require confirmation of cure following initial exploration.51

Initial postoperative serum iPTH levels are commonly elevated in the context of low calcium following curative resection. This is usually a postoperative normal physiologic response

Indications for surgical re-exploration

Surgical intervention for PHPT in patients with no previous surgical intervention affords a cure rate greater than 95%. There are no data specifically addressing the efficacy of surgical versus nonsurgical interventions for recurrent or persistent asymptomatic disease, however, and it is reasonable to consider similar guidelines when assessing asymptomatic patients with persistent or recurrent disease for surgical referral.

Preoperative evaluation

A careful preoperative assessment is required to optimize outcomes for these challenging patients. A thorough history and physical examination, including laryngoscopic vocal cord evaluation and biochemical verification of PHPT, should be considered in preoperative evaluation. The risk of increased morbidity associated with re-exploration should be discussed with the patient. Asymptomatic patients with persistent or recurrent disease referred for surgical evaluation who have borderline elevation

Operative techniques

Hyperfunctioning parathyroid tissue in reoperative PHPT can be usually resected by a cervical incision. Medial approach is the standard approach for exploration, which attempts to use the operative planes explored during the patient's initial surgery. Lateral approach, dissecting the plane between the strap muscles and the sternocleidomastoid muscle, allows avoidance of scarred tissues from previous exploration and allows posterior access to the thyroid bed.56 Medial approach, however, allows

Postoperative care

Cure rates following surgical re-exploration are between 94% and 96% with low complication rates in cases performed by experienced surgeons (Hessman, 2008). 60 These patients require careful postoperative care, however, because they are at risk for RLN injury and postoperative hypocalcemia.

Reoperative surgery for patients with recurrent or persistent PHPT remains a significant challenge. If persistent or recurrent disease is biochemically confirmed, thorough assessment should be carefully

Summary

The evolution of PHPT since it was first recognized nearly 100 years ago has been profound because of technologic and biochemical advances that have furthered the knowledge and the ability to effectively treat the disease. Understanding the genetics of the disease also plays a major role in the management of patients with familial syndromes that encompass PHPT. Preoperative localization has revolutionized the surgical decision-making process along with the use of IOPTH assays to determine

First page preview

First page preview
Click to open first page preview

References (60)

  • D.M. Carneiro-Pla et al.

    Consequences of targeted parathyroidectomy guided by localization studies without intraoperative parathyroid hormone monitoring

    J Am Coll Surg

    (2006)
  • D.M. Carneiro et al.

    Comparison of intraoperative iPTH assay (QPTH) criteria in guiding parathyroidectomy: which criterion is the most accurate?

    Surgery

    (2003)
  • M. Shindo

    Intraoperative rapid parathyroid hormone monitoring in parathyroid surgery

    Otolaryngol Clin North Am

    (2004)
  • F.F. Palazzo et al.

    Minimal-access/minimally invasive parathyroidectomy for primary hyperparathyroidism

    Surg Clin North Am

    (2004)
  • D.J. Terris et al.

    Contemporary parathyroidectomy: exploiting technology

    Am J Otolaryngol

    (2007)
  • J. Brennan et al.

    Prospective analysis of the efficacy of continuous intraoperative nerve monitoring during thyroidectomy, parathyroidectomy, and parotidectomy

    Otolaryngol Head Neck Surg

    (2001)
  • C.R. Harman et al.

    Indications, technique, and efficacy of alcohol injection of enlarged parathyroid glands in patients with primary hyperparathyroidism

    Surgery

    (1998)
  • T.S. Reeve et al.

    Minimally invasive surgery for primary hyperparathyroidism: systematic review

    Arch Surg

    (2000)
  • R.A. DeLellis et al.

    Primary hyperparathyroidism: a current perspective

    Arch Pathol Lab Med

    (2008)
  • S.E. Rodgers et al.

    Primary hyperparathyroidism

    Curr Opin Oncol

    (2008)
  • M.H. Wheeler

    Primary hyperparathyroidism: a surgical perspective

    Ann R Coll Surg Engl

    (1998)
  • J.P. Bilezikian et al.

    Guidelines for the management of asymptomatic primary hyperparathyroidism: summary statement from the third international workshop

    J Clin Endocrinol Metab

    (2009)
  • E.M. Brown

    The calcium-sensing receptor: physiology, pathophysiology and CaR-based therapeutics

    Subcell Biochem

    (2007)
  • E.M. Brown

    Clinical lessons from the calcium-sensing receptor

    Nat Clin Pract Endocrinol Metab

    (2007)
  • S. Miedlich et al.

    Update on genetic and clinical aspects of primary hyperparathyroidism

    Clin Endocrinol (Oxf)

    (2003)
  • T. Carling et al.

    Parathyroid surgery in familial hyperparathyroid disorders

    J Intern Med

    (2005)
  • M. Blackburn et al.

    Primary hyperparathyroidism and familial hyperparathyroid syndromes

    Aust Fam Physician

    (2007)
  • R. Eastell et al.

    Diagnosis of asymptomatic primary hyperparathyroidism: proceedings of the third international workshop

    J Clin Endocrinol Metab

    (2009)
  • T. Okamoto et al.

    Parathyroid carcinoma: etiology, diagnosis, and treatment

    World J Surg

    (2009)
  • L.H. Coker et al.

    Primary hyperparathyroidism, cognition, and health-related quality of life

    Ann Surg

    (2005)
  • Cited by (48)

    • Impact of Perinatal Primary Hyperparathyroidism on Maternal and Fetal and Neonatal Outcomes: Retrospective Case Series

      2020, Journal of Obstetrics and Gynaecology Canada
      Citation Excerpt :

      The diagnosis is made by measuring elevated serum calcium levels with inappropriately normal or elevated PTH levels. It is the third most frequent endocrine disorder, following diabetes mellitus and thyroid disease,2 with approximately 25% of cases in women of child-bearing age.3,4 It was first described in pregnancy in 19315; however, its detection remains difficult because only 20% of patients are symptomatic,4,6 and certain manifestations may be mistaken for common pregnancy-related discomforts.

    • Parathyroid Adenoma: Our Experience

      2023, Otorhinolaryngology Clinics
    • Case studies in thyroid and Parathyroid Tumors

      2023, Case Studies in Thyroid and Parathyroid Tumors
    View all citing articles on Scopus
    View full text