Primary Hyperparathyroidis

mPresenter :Dr Junaid Ahmad Sofi ,Surgical Resident –II year

Moderator :Prof (Dr) Aijaz Ahmad Malik

SaturdayMay’ 28

DEPARTMENT OF GENERAL & MINIMAL INVASIVE SURGERY , SKIMS, Srinagar , J&K

Parathyroids

Anatomy / Embryology and Physiology Four parathyroid glands –3 x 3 x 3 mm

30 – 50 mg Flat, ovoid and light beige and only

slightly darker or brown compared to adjacent fat.

Variability in no (2-6). & position. 2 Superiors are behind recurrent

laryngeal nerve. develop from 4th pharyngeal pouch hence called as parathyroid IV

MC location glands is within a distance of 1 cm from a point centered where the inferior thyroid artery and RLN cross. The upper parathyroidglands usually are superior to this junction and dorsal (posterior)to the nerve, whereas the lower glands are located inferior to thejunction and ventral (anterior) to the recurrent nerve.

Position of superior parathyroid glands is more consistent, with 80% of these glands being found near the posterior aspect of the upper and middle thyroid lobes, at the level of the cricoid cartilage. Approximately 1% of normal upper glands may be found in the paraesophageal or retroesophagealspace

POSSIBLE LOCATIONS FOR SUPERIOR THYROID GLANDS

• 2 inferior glands-variable in position, develop from endoderm of 3rd pharyngeal pouch hence called as parathyroid III, usually in front of the recurrent laryngeal nerve, lower part.

• Variations are common in inferior parathyroids. It can be located in thyrothymic ligament, superior pole of thyroid,tracheooesophageal groove, behind oesophagus, carotid sheath. Approximately 15% of inferior glands are found in the thymus.

• Inferior thyroid artery – main blood supply

• 4th – 5th weeks of fetal life – pharyngeal pouches developed

• 4th pouch + lateral thyroid anlage = superior gland

• 3rd pouch + thymus = inferior gland

• There may be more than two glands on one side called as supernumerary gland (2.5-22%).

• Both superior and inferior glands receive their blood supply from inferior thyroid artery and its anastomotic branch.

• Blood supply is through an end arterial branch.

• Gland contains chief and oxyphil (water clear) cells.

POSSIBLE LOCATIONS FOR INFERIOR THYROID GLANDS

If one inferior gland is located find other on the opposite side at the same level This is not true for superior glands

RLN crossing Simon’s triangle formed by trachea, ITA and common carotid artery

The superior parathyroid gland lies deep (dorsal) and the inferior parathyroid superficial (ventral) to a coronal plane along course of RLN

Actions of parathormone hormone:Increase serum calcium level by:

Decrease serum phosphate level by:

Ca re-absorption from renal tubules.Ca absorption from the GIT.Bone resorption

Increase serum excretion of phosphate.

• Half life of PTH is 4 minutes.

Histologically• chief cells and oxyphil cells • arranged in trabeculae, within a stroma composed primarily of

adipose cells.• third group of cells- water-clear cells, also are derived from chief cells,

are present in small numbers, and are rich in glycogen. • Although most oxyphil and water-clear cells retain the ability to

secrete PTH, their functional significance is not known.

Hyperparathyroidism

Hyperparathyroidism 3rd most common endocrine disease after diabetes and thyroid disease. excessive secretion of Parathyroid hormone (PTH)

extensively above the normal level (12-70 pg/mL) , HPT can be characterized into primary, secondary, and

tertiary forms

Hyperparathyroidism

Primary

Parathyroid

adenoma

Parathyroid

hyperplasia

Parathyroid

carcinoma

Secondary

Parathyroid

hyperplasia

Tertiary

Autonomous nodule on

top of hyperplasia

Single adenoma80% of casesA rim of normal parathyroid tissue around the adenoma distinguishes

adenoma from hyperplasia Hyperplasia

15-20% of cases. No rim of normal parathyroid tissue and lack of stromal fatsAll 4 glands are involved. The hyperparathyroidism of MEN syndromes is due to hyperplasia.

Parathyroid carcinoma - <1% of cases.Exceptionally high calcium or palpable neck mass should raise

suspicion. Excision with thyroid lobectomy is indicated. Radical neck dissection for recurrent disease. Recur locally 30%;

distant metastasis to lung liver and bone in 30%.Difficult to distinguish adenoma from hyperplasia histologically

Primary Hyperparathyroidism

MEN type I (MEN 1 gene) MEN type II

•Parathyroid adenoma, •(earliest & m.c manifestation is PHPT & develops in 80-100% by 40 yrs )•Pituitary adenoma •Pancreatic islet cell tumor

•Parathyroid adenoma, •Thyroid medullary carcinoma & •Pheochromocytoma

Secondary hyperparthyroidism Hyperplasia of the parathyroid in response to decreased serum calcium level. Renal osteodystrophy/CRF

Tertiary hyperparathyroidism Autonomous parathyroid fuction on top of parathyroid hyperplasia even after renal

transplant

• PHPT occurs in 0.1% to 0.3% of the general population• More common in women (1:500) than in men (1:2000).• increased PTH production leads to hypercalcemia via :

• increased GI absorption of calcium• increased production of vitamin D3,• reduced renal calcium clearance.

• PHPT is characterized by increased PTH secretion that is independent of calcium levels.

Classical Pentad : (Kidney Stones, Painful Bones, Abdominal groans, Psychic moans & fatigue overtones)

Most common clinical presentation of primary hyperparathyroidism ? ~ 80 %

Minimally symptomatic / asymptomatic hypercalcemia detected by routine biochemical screening.B

Biochemical screening tests that include measurements of serum calcium currently account for the identification of at least 80 % of patients with primary hyperparathyroidism (PHPT) in western countries .

Minimal symptoms including : weakness, fatigue, polydipsia, polyuria, nocturia, bone and joint pain, constipation, decreased appetite, nausea, heartburn, pruritus, depression, and memory loss

Truly asymptomatic <5%

< Trabecular bone resorption SALT PEPPER APPEARANCE

< Subperiosteal bone resorption Phalangeal tufts.

Brown tumor (osteitis fibrosa cystica)

Replacement of bone by vascularized fibrous tissue secondary to PTH stimulated osteoclastic activity

Expansile lytic lesion with well defined non sclerotic margin.

Location: They are usually eccentric

Hyper parathyroidism

Skeletal

Osseous

Bone resorption

Diffuse osteoporosis

Regional osteosclerosis

Bone softening

Periostitis

Brown tumor

Articular

Erosive arthritis

Chondrocalcinosis

Soft tissue

Visceral calcification

Soft tissuecalcification

Vascularcalcification

CLINICAL MANIFESTATIONS Renal Polyuria ,Polydipsia ,Nephrolithiasis , Nephrocalcinosis ,Distal renal tubular acidosis , Nephrogenic diabetes insipidus ,Acute and chronic renal insufficiency

Gastrointestinal Anorexia, nausea, vomiting Bowel hypomotility and constipation Pancreatitis Peptic ulcer disease

Musculoskeletal Muscle weakness ,Bone pain ,Osteopenia/osteoporosis

Neurologic Decreased concentration ,Confusion , Fatigue ,Stupor, coma

Cardiovascular Shortening of the QT interval, Bradycardia ,Hypertension (unknown )

Diagnosis elevated serum Ca2+ and intact PTH or two-site PTH

levels, without hypocalciuria, establishes the diagnosis of PHPT with virtual certainty.

PTH assays use immunoradiometric or immunochemiluminescent techniques and can reliably distinguish PHPT from other causes of hypercalcemia. Furthermore, they do not crossreact with PTHrP

Urinary calcium levels need not bemeasured routinely, except in patients who have not had previously documented normocalcemia or have a family history of hypercalcemia to rule out FHH. In FHH, 24-hoururinary calcium excretion is characteristically low (<100 mg/d).& serum calcium-to-creatinine clearance ratio usually is <0.01 in patients with FHH, whereas it is typically>0.02 in patients with PHPT.

Hypercalcemic Crisis. Patients with PHPT may occasionally present acutely with nausea, vomiting, fatigue, muscle weakness, confusion, and a decreased level of consciousness—a complex referred to as hypercalcemic crisis

• symptoms result from severe hypercalcemia from uncontrolled PTH secretion, worsened by polyuria, dehydration, and reduced kidney function

• Treatment consists of therapies to lower serum calcium levels followed by surgery to correct HPT.

• rehydration with a 0.9% saline solution to keep urine output >100 cc/h.

• Once urine output is established, diuresis with furosemide• Occasionally, in life-threatening cases/ CRF -> hemodialysis

PHPT TREATMENT :Medical options

antiresorptive treatments such as bisphosphonates hormone replacement therapy (HRT),( other side effects ) selective estrogen receptor

Bisphosphonates and HRT are reasonable options in patients for whom skeletal protection is needed.

More recently, calcimimetics (CINACALCET) (modifiers of the sensitivity of the CASR) have been used in randomized, multicenter controlledtrials and have been shown to decrease both serum calcium and PTH levels in both symptomatic and asymptomatic PHPT patients. Unfortunately, bone density failed to improve in medically treated patients

Indications for Parathyroidectomy and Role of Medical Management. patients who have developed complications and have “classic”

symptoms of PHPT should undergo parathyroidectomy asymptomatic PHPT has been the subject of controversy

Indications for parathyroidectomy in patients with asymptomatic primary HPT (2009 NIH consensus conference guidelines)

Serum calcium >1 mg/dL above the upper limits of normal GFR <60 mL/min Substantially decreased bone mineral density at the lumbar spine, hip, or

distal radius (>2.5 SD below peak bone mass, T score <−2.5 Age <50 y Long-term medical surveillance not desired or possible

The significant changes from the previous guidelines pertain to the fact that (a) hypercalciuria (>400 mg/24 h), in the absence of nephrolithiasis, is no

longer considered an indication for parathyroidectomy; (b) an absolute glomerular filtration rate <60 mL/min, rather than a

reduction of creatinine clearance by 30%, is used as a thresholdfor recommending surgery

The Fourth International Workshop on the Management of Asymptomatic Primary Hyperparathyroidism reviewed evidence that has become available since the last Workshop

in 2008.2

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UID

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(VFA vertebral fracture assessment) and trabecular bone score (TBS) by DXA

Surgical Management

Successful parathyroidectomy results in resolution of osteitis fibrosa cystica and decreased formation of renal stones in symptomatic (classic) patients.

Improved BMD (6% to 8% in the first year and up to 12% to 15% at 15 years) and fracture risk (by 50% at hip and upper arm and30% overall) after adjustment for age, sex, and previous fractures over a 20-year observation period.

improves a number of the nonspecific manifestations of PHPT such as fatigue, polydipsia, polyuria and nocturia, bone and joint pain, constipation, nausea, and depression in many patients.

Hence , it is recommended that parathyroidectomy should be offered to virtually all patients except those in whom the operative risks are prohibitive. This is also acknowledged by the panel of the latest workshop, which stated that “even though patients may not meet the guidelines for surgical intervention, it is always a reasonable option in those who do not have medical contraindications.”

Surgical options – Primary Hyperparathyroidism With single adenoma, resection of the gland is

curative. For hyperplasia,

3 ½ gland resection 4-gland resection with ½ gland reimplanted in

the forearm or sternocleidomastoid muscle is indicated.

For parathyroid carcinoma Neck exploration with en bloc excision of the

tumor and the ipsilateral thyroid lobe, in addition to the removal of contiguous lymph nodes (tracheoesophageal, paratracheal, and upper mediastinal).

The recurrent nerve is not sacrificed unless it is directly involved with tumor.

Adherent soft tissue structures (strapmuscles or other soft tissues) should also be resected.

Modified radical neck dissection is recommended in the presence of lateral lymph node metastases. suspected preoperatively by the presence of

severe symptoms, serum calcium levels>14 mg/dL, significantly elevated PTH levels (five times

normal), a palpable parathyroid gland.

Initial exploration is successful in 90-95% of cases without pre-op localization studies.

Ectopic locations: Thymic – substernal – 20%; Posterior neck – 5-10%; Intrathyroid – 5%; Carotid sheath – 1%; Anterior mediastinum – 1-2%.

If initial exploration fails – localization studies are indicated.

Approaches for parathroidectomy :

Standard Bilateral exploration-Conventional approach If parathyroid localization studies or IOPTH arent avaialable If localization studies fail to identify any abnormal glands If localization studies identify multiple abnormal glands If concomitant thyroid disorder requires B/L exploration

Targeted/Focussed Approach  Minimally invasive parathyroidectomy Radio Guided parathyroidectomy using hand held gamma probe Endoscopic approaches (especially for ectopic parathyroids in mediastinum) Robotic gasless , transaxillary techniques

Preoperative Localization

imaging is not a diagnostic approach, and the decision for exploration should be made before any imaging is performed

Localization studies have permitted surgeons to perform more limited operations including unilateral and focused neck exploration, radio-guided parathyroidectomy, and several endoscopic or video-assisted approaches.

Benefits of Preoperative Localization: decreased operative times reduced duration of hospital stay Smaller Incision , improved cosmetic outcomes Success rates similar to those obtained with traditional bilateral neck explorations Different Anesthesia Options Ambulatory vs. Overnight Decrease Rate of Missed or Multiple Adenomas

PREOP NON INVASIVE LOCALIZATION Sestamibi or MIBI scintigraphy (methoxyisobutylisonitrile ) taken up by the mitochondria in thyroid and parathyroid tissue. DISADVANTAGES : - unrevealing in parathyroid hyperplasia, multiple parathyroid

adenomas, and in those with coexisting thyroid disease. -falsely negative scans can also be caused by calcium channel blockers

that interfere with the take up of the isotope by parathyroid cells . -Other gland characteristics that can increase the likelihood of a

negative scan include small size, superior position, and a paucity of oxyphil cells.

Sestamibi scanning for parathyroid tissue can be enhanced by combination with three-dimensional imaging (SPECT) & Subtraction thyroid scan ie Sestamibi -Technitium-99m subtraction scintigraphy

Technetium-sestamibi scans 15 minutes and 3 hours afterinjection showing retention of isotope in a left inferior parathyroidadenoma.

Sestamibi -Technitium-99m subtraction scintigraphy. most widely used and accurate modality with a sensitivity >80% for detection

of parathyroid adenomas. useful for parathyroid localization due to the delayed washout of the

radionuclide from hypercellular parathyroid tissue compared to thyroid tissue.

Sestamibi Technitium-99m subtraction scintigraphy.

• SPECT — Sestamibi-single photon emission computed tomography (SPECT or MIBI-SPECT).

three-dimensional sestamibi scan that provides higher resolution imaging and improves the performance of sestamibi scanning.

ADVANTAGE : SPECT imaging substantially reduces the likelihood of missing multiglandular disease compared to planar imaging

(MIBI SCAN)( Sestamibi scintigraphy) combined with sestamibi single photon emission computed tomography (SPECT) has the highest positive predictive value of the available imaging techniques and some prefer this as the localizing procedure of choice for initial surgery

MIBI scan with single photon emission computed tomography showing hot spot in anterior mediastinum (arrow)

Neck ultrasonography (high Frequency USG) highly sensitive in experienced hands inexpensive, noninvasive, and reproducible

in the operating room. helpful for the characterization and evaluation of any thyroid pathology,

facilitating operative planning. This is a common problem, since concurrent thyroid pathology is present in up to 30 percent of patients with primary hyperparathyroidism.

Operator dependent Sensitivity is reduced in patient With thyroid nodule Sonographic characteristics of parathyroid adenomas include homogeneous

hypoechogenicity and an extrathyroidal feeding vessel with peripheral vascularity seen on color Doppler imaging .

False-negatives result from substernal ,ectopic, and undescended tumors

Ultrasound views of parathyroid adenomas.(A) Sagittal image of the upper pole of the right lobe of the thyroid

gland, demonstrating a hypoechoic parathyroid adenoma posterior to the thyroid parenchyma.

(B) Sagittal image of the lower pole of the lower pole of the left lobe of the thyroid gland with an adjacent hypoechoic parathyroid

adenoma measuring 9 mm in greatest dimension

Magnetic resonance imaging  Localization of ectopic tumors No radiation exposure Expensive False positive results from thyroid nodules & lymph nodes

Parathyroid adenoma characteristics on magnetic resonance imaging (MRI) include intermediate to low signal intensity on T1 imaging and high intensity on T2 imaging.

CT & 4D CT scan

CT are less sensitive than sestamibi scans,but are helpful in localizing large paraesophageal and mediastinal glands.

4 D C T Incorporates the perfusion of contrast in hyperfunctioning parathyroid tissue over time, thus providing functional information in addition to the anatomic information provided by conventional three-dimensional CT imaging.

In one study 4D-CT showed improved sensitivity of 88% compared to that of sestamibi (65%) and ultrasound (57%) for lateralization of the enlarged gland and also showed superiority when localization to the correct quadrant was examined.

A combination of 4D-CT and ultrasound has been reported to have a positive predictive value of 92% for single-gland disease and 75% for multiple-gland disease.

Non-localizing imaging studies should not preclude initial surgery for patients with biochemically confirmed primary hyperparathyroidism who meet operative criteria. In such patients, a single adenoma is still the most likely intraoperative finding (62 to 77 percent)

PREOPERATIVE , INVASIVE LOCALISATION

prior neck surgery whom noninvasive testing has been unrevealing.Selective venous sampling : A 1.5 to 2-fold increase in parathyroid hormone

levels obtained from representative cervical vein drainage locations (inferior, middle, superior thyroid, thymic, and/or vertebral veins

Selective arteriography positive localization is considered an increase in the parathyroid hormone level to 1.4 times the baseline or a blush seen on arteriography

A baseline PTH value is obtained at the start of the procedure, PTH levels are then measured at following removal of the suspected adenoma . A reduction of >=50 percent from the baseline following excision of the hyperfunctioning gland after 10 mins is an accepted standard for intraoperative confirmation of success.

INTAOPERATIVE LOCALISATION USING GAMMA PROBE 1 to 2 mCi of the isotope is injected before surgery, and a hand-held gamma probe is

used to guide the identification of the enlarged gland

INTAOPERATIVE , INVASIVE LOCALISATION

Use of gamma probe intra op

Comprehensive ParathyroidectomySystematic Examination of all Parathyroid Glands in their Usual Anatomic Location and Appropriate

Resection of Diseased Parathyroids

For patients with negative (non-localizing) preoperative imaging studies or when bilateral foci are detected.

Most forms of hereditary hyperparathyroidism are an indication for bilateral parathyroid exploration due to the predictable involvement of multiple glands.

Concomitant thyroid disease requiring surgical resection, such as biopsy proven papillary thyroid cancer, necessitates bilateral exploration.

pregnant patients due to the radiation required for some localization studies. However, if ultrasound expertise is available and the results show an apparent single adenoma, a focused approach can be planned.

lithium associated hyperparathyroidism has a higher incidence of being associated with multiple gland involvement and may require bilateral exploration.

■Focused parathyroid exploration  When combined with use of intraoperative PTH monitoring, minimally invasive

parathyroidectomy techniques result in excellent outcomes that are comparable to a traditional bilateral cervical exploration.

Advantages :

The smaller incisions and less extensive dissection lead to reduced postoperative pain and a lower incidence of hypocalcemia from ischemia of other glands.

Indications:

-No discordance between sistamibi & USG

-imaging suggesting unilateral pathology.

-no suggestion of concomitant, thyroid disease requiring surgical intervention.

-no family history of multiple endocrine neoplasia.

How do we do it1 . Consent for Possibilities of: persistent hyperparathyroidism (5 per cent); recurrent laryngeal nerve injury (1 per cent); postoperative haemorrhage (1 per cent); permanent hypoparathyroidism; recurrent hyperparathyroidism

initially after first surgery HPT is corrected but recurs 12 months after surgery) is due parathyromatosis, development of new adenoma, and hyperplasia of transplanted parathyroid. Parathyromatosis is due to rupture and spillage of parathyroid tissue in neck, mediastinum forming functioning nodules

Operative strategy and technique of parathyroidectomy Conventional approach Helpful to mark incision site when patient is awake positioned in supine, neck extended with the head supported in a padded ring. A transverse collar incision is made, the subplatysmal plane developed superiorly

till thyroid cartilage and inferiorly till supra sternal notch and the avascular midline raphe is incised in the midline between the strap muscles

sternothyroid is are separated from Sternohyoid & loose areolar tissue between sternothyroid & thyroid is taken down at the lateral edge of sternothyroid to prevent lateral displacement of parathyroid

Thyroid lobes are mobilised with division of the middle thyroid vein when present. It is not normally necessary to divide the superior thyroid vessels unless the exploration proves difficult

Medial rotation of the thyroid lobe exposes the inferior thyroid artery and recurrent laryngeal nerve

Inferior glands are identified first as superior glands require more medial rotation of thyroid

Bloodless field is maintained , as blood staining makes parathyroids less noticable

The glands are identified in a systematic manner commencing with the common sites and working sequentially through to the rare locations.

Superior gland: 1 in fat pad on surface of thyroid lobe above the inferior thyroid artery at level of

cricothyroid articulation then 2 inferiorly behind the inferior thyroid artery and oesophagus then 3 divide superior thyroid vessels and rotate upper pole anteriorly.

Inferior gland: 1 along the thyrothymic axis then 2 on or under the capsule of the lower pole of the thyroid then 3 incise the fascia of the upper horn of thymus then 4 extend this down into the accessible mediastinal thymus then 5 within the carotid sheath (usually suggested by a tongue of ectopic thymus) then 6 transcervical thymectomy achieved by gentle upper retraction on the thymic lobe then 7 within the thyroid lobe which may require thyroid lobectomy.

All abnormal glands are excised In sporadic four-gland disease, subtotal parathyroidectomy is carried out, preserving

approximately 50 mg of one gland marked with a non-absorbable suture to facilitate any possible future re-exploration.

In patients with four-gland disease, transcervical thymectomy is recommended to reduce the risk of persistent or recurrent hyperparathyroidism.

In patients with MEN-1, total parathyroidectomy reduces the risk of recurrence.

The thin fascia overlying a “suspicious” fat lobule should be incised using a sharp curved hemostat and scalpel.This maneuver often causes the parathyroid gland to “pop” out. Alternatively, gentle, blunt peanut sponge dissection between the carotid sheath and the thyroid gland often reveals a “float”sign, suggesting the site of the abnormal parathyroid gland.

Intra Op adenoma: Brown with gritty sensation on incising Sinks in water

Operative strategy and technique of parathyroidectomy

Focussed / Targeted approach General or local anaesthesia Confident preoperative localisation permits a 2–3 cm incision located over the

site of the adenoma Subplatysmal plane is incised and either a midline or lateral approach to the

strap muscles permits development of the plane between the thyroid capsule and carotid artery and jugular veins

Adenoma is mobilised staying close to but avoiding rupture of the capsule. Identification of the recurrent laryngeal nerve is not routine and only bipolar diathermy should be used.

Targeted parathyroid surgery; a 2-cm incision over leftinferior parathyroid adenoma.

Median Sternotomy (3%) Extension

Median sternotomy is often needed when parathyroid is in anterior mediastinum along with thymus. Often parathyroid may be 5, 6 in numbers instead of four

Complication of parathyroidectomy ? :

Hematoma Wound infection Postoperative hypocalcemia ( transient / hungry bone syndrome ) Permanent hypoparathyroidism  Recurrent laryngeal nerve injury(1%) Persistent hyperparathyroidism—5% (PTH never touches baseline -6 mo) Recurrent hyperparathyroidism—initially PTH decreases but

hypercalcaemia recurs 6 months after first parathyroid surgery

The hypocalcemia is generally transient , Transient hypoparathyroidism may be due to manipulation of the blood supply to or removal of one or more parathyroid glands during surgery .

In some cases, however, the postoperative hypocalcemia is severe and prolonged despite normal or even elevated levels of parathyroid hormone (PTH). This phenomenon, called the hungry bone syndrome.

most often occurs in patients who have developed bone disease preoperatively due to a chronic increase in bone resorption induced by high levels of PTH (osteitis fibrosa).

Hypocalcemia after parathyroidectomy

Time course of development of hypocalcemia in 25 patients following parathyroidectomy for primary hyperparathyroidism. Most of the fall in the plasma calcium concentration occurred in the first 24 hours after surgery.

D/D for the patient with hypocalcemia ?

-Hungrey bone syndrome (PTH level normal ).

-Vitamine D deficiency.

-Both.

-Malabsorption.

-Permanent hypoparathyroidism (injuried glands )( low PTH ).

Criteria for diagnosis of hungrey bone syndrome ?

serum calcium concentration below 8.5 mg/dL (2.13 mmol/L) and the serum phosphate postoperative conentration below 3.0 mg/dL (0.96 mmol/L) on the third day post op.

Patients at risk ?

1-Volume of the resected adenoma.2-Preoperative blood urea nitrogen concentration.3-Preoperative alkaline phosphatase concentration.4-Older age.

Preoperative serum calcium and PTH levels did not provide additional predictive information.

Some studies do point towards pre-op calcium has a indicator for the same

Presentation of hungry bone syndrome :

-Hypocalcemia . -Hypophosphatemia : The decrease in bone resorption and increase in bone formation that

occurs after parathyroidectomy can also lead to hypophosphatemia.

-Hypomagnesemia : refractory hypocalcemia.

-Hyperkalemia (80 percent) ( unknown ).  

How it can be prevented ? Preoperative preparation

-starting oral calcium 2 to 3 grams per day two days prior to surgery, even in patients who are hypercalcemic.

-intravenous calcitriol : in Vit D deficiency , CRF(vitamin D2) (1000 IU per day or more depending on

level) in vit D def pts , (2 mcg at the end of each hemodialysis treatment) in HD pts , begun three to five days prior to surgery and continued postoperatively may be helpful in preventing marked hypocalcemia.

How it can be treated ?

  Treatment is aimed at each of the abnormalities that can occur: hypocalcemia, hypomagnesemia, hypophosphatemia, and hyperkalemia.

the serum calcium concentration should be measured two to four times per day for the first few postoperative day .

Oral calcium supplementation (2 to 4 g of elemental calcium [50 to 100 mmol] per day) should be started as soon as the patient is able to swallow.

If the serum phosphorus is normal or low, calcium should be administered between meals to maximize intestinal absorption and minimize phosphate binding.

Intravenous calcium is indicated if the patient develops a rapid and progressive reduction in serum calcium or symptoms related to hypocalcemia, including frank tetany, latent tetany (Chvostek's or Trousseau's sign), or a plasma calcium concentration below 7.5 mg/dL (1.9 mmol/L).

the administration of phosphate to reverse hypophosphatemia is generally avoided in patients with hungry bone syndrome, since phosphate can combine with calcium and further reduce the plasma calcium concentration. An exception to this general rule is the presence of severe hypophosphatemia, in which the plasma phosphate concentration is below 1 mg/dL.

TREATMENT OF CONCOMITANT VITAMIN D DEFICIENCY  ? 

the Third International Workshop on Asymptomatic Primary Hyperparathyroidism recommends measuring 25OHD in all patients with PHPT and repleting those with low levels (defined as ≤20 ng/mL [50 nmol/L]) prior to making any management decisions .

Cautiously repleting vitamin D in patients with underlying hyperparathyroidism since worsening hypercalcemia and hypercalciuria have been reported in this setting .

Add on Intra op Parathyroid adenomas are brown with gritty feel Parathyroids sink in water ; fat doesnt ??Intraop indocyanin green(as for hepatic functions) assay for parathyroid

localisation..infra red light 2 site pth assay

Sandwich assays (two antibodies for C n N terminus of Intact PTH Two site sampling IJV & peripheral vein sampling

Calcium replacement(1-1.5meq/kg/day replacement) Persistant hyperparathyroidism : elevated calcium & PTH within 6 months

of surgery Recurrent hyperparathyroidism :levated calcium & PTH that occurs more

than 6-12 months after surgery Implantation in forearm for easy reexplloration