Primary hyperparathyroidism (PHPT) encompasses asymptomatic endocrine disor­der, symptomatic endocrine disease, and recently detected normocalcemic hyper­parathyroidism. It is most likely that the community prevalence of PHPT always has the mixture of the three different forms but has different regional proportions. In

Benign familial hypocalciuric hypercalcemia is characterized by a mild increase in both serum calcium and intact PTH levels. The 24-h urine calcium in these cases is low. Here the calcium to creatinine clearance ratio is <0.01, unlike primary hyper­parathyroidism where the ratio is more than 0.02. Benign familial hypocalciuric hypercalcemia is an autosomal dominant trait. Parathyroidectomy is not indicated in this condition.

Most of the familial cases occur in association with Multiple Endocrine Neoplasia (MEN). However, there is a distinct clinical entity known as non-MEN familial hyperparathyroidism. These patients present with profound hypercalcemia, and some present with hypercalcemic crises. These patients have multiple abnormal parathyroid glands, either synchronously or metachronously, and are at risk of per­sistent and recurrent hyperparathyroidism. They need to be treated aggressively.

(b) Hypercalcemia associated with bone metastases. Local osteolytic hypercalce-

(c) Hypercalcemia is associated with hemotological malignancies like multiple

The important differences in humoral hypercalcemia and primary hyperparathy­roidism are the low plasma chloride, high bicarbonate, and urinary cyclic AMP in the former.

Hypercalcemia is a sign of advanced malignancy and one needs to treat the underlying malignancy. Life-threatening complications of high serum calcium require emergency management. Medication used to treat hypercalcemia of malig­nancy includes Bisphosphonates, Lenosumab, (a monoclonal antibody that inhibits the differentiation of osteoclasts), and Calcitonin.

The serum calcium values are always subnormal and serum PTH values also remain low in hypocalcemia of parathyroid origin. Postoperative hypoparathyroid­ism manifests usually 24–48h after surgery and estimation PTH is a good predictor of hypocalcemia. Postoperative hypoparathyroidism can be transient and calcium values return to normal in a week. The hungry bone syndrome is typically associ­ated with symptomatic hypocalcemia and treatment for several weeks is required. Severe symptomatic hyperparathyroidism with marked bone mineral loss is a usual candidate to develop post-parathyroidectomy hypocalcemia requiring calcium and dihydroxy vitamin D supplementation for a long time.

Calcium homeostasis is closely dependent on phosphate, magnesium, and vita­min D.For effective absorption of calcium from the G I tract dihydroxy vitamin D is required. Serum magnesium levels also require close monitoring and correction of hypomagnesemia is essential for maintaining normocalcemic levels as well as recovery of neuromuscular symptoms. Treatment of postoperative hypoparathy­roidism is based on the degree of hypocalcemia and severity of symptoms. If the serum calcium level is below 7.5mg/dl and the patient is symptomatic an infusion of 10 ampoules of calcium gluconate in 1L of 5% dextrose is given at 100ml/h with serum calcium estimations at regular intervals. For patients who are mildly symp­tomatic and whose calcium, values are between 7.5–8.5mg/dl, 1000 mg of oral calcium can be given every 6h with 0.25–2μg/day of Calcitriol. It is also advisable to check vitamin D and magnesium levels and supplement them if the levels are below normal. Currently, two types of recombinant PTH are available as subcutane­ous injections given twice daily.

Pseudohypoparathyroidism is a heterogeneous group of disorders characterized by PTH resistance. Patients present with hypocalcemia and hyperphosphatemia due to impaired target tissue response to PTH.This is an autosomal dominant disorder. In Type-Ib: pseudohypoparathyroidism there is resistance to multiple hormones PTH, TSH, Luteinizing hormone, and gonadotrophic releasing hormone. The defects include short stature, obesity, round facies, brachymetacarpia, subcutaneous ossi­cation, and mental retardation (Albright’s hereditary osteodystrophy). Patients with pseudohypoparathyroidism 1b lack the features of Albright’s hereditary

The bits from parathyroids for cryopreservation are sent for frozen, conrmed as parathyroids, and then prepared for preservation. Freezing media is an 80% Rosewell park memorial institute (RPMI) 1640 solution with the addition of DMSO in 10% of autologous serum. The vials are placed in a freezer where the temperature goes down gradually from –1°C to –80°C.The vials are relocated into a liquid nitrogen freezer at –170 °C. When required the vials are placed in a water bath at 37–42°C.They are rinsed in an RPMI solution at 37°C three times. The parathy­roids are now ready for implantation.

Symptomatic PHPT is not an uncommon disease in Asian countries. The demo­graphic prole differs with the higher frequency of male patients and the average age of patients is a decade younger than the western counterpart. The skeletal prole of osteitis brosa cystica, brown tumors of the long bones, and fragility fractures are still seen in patients in India. Other less severe symptoms related to the musculo­skeletal system include diffuse bone pain, arthralgia, and myopathy affecting the pelvic girdle muscles. Because of bizarre clinical presentation diagnosis of PHPT is delayed considerably.

Gastrointestinal manifestations are mostly related to hypercalcemia, stone dis­eases in the gall bladder and pancreas, or primary tumors seen in MEN 1 syndrome. Recurrent acute pancreatitis is a primary presentation of PHPT and is considered as complication hypercalcemia.

A constellation of symptoms such as anorexia, nausea, vomiting, polyuria, dehy­dration, drowsiness, stupor, coma, renal insufciency, cardiac dysrhythmias are seen. The diagnosis of hypercalcemic crisis can be made when the serum calcium is more than 14.5mg/dl and acute symptoms and signs can be reversed by correcting the hypercalcemia. All these patients need emergency admission in high depen­dency wards, close monitoring, emergency measures to lower the serum calcium, and support to deteriorating general condition. Volume expansion by intravenous infusion of normal saline (150ml/h) is initiated and maintained. For quick control of hypercalcemia calcitonin is used as a nasal spray or subcutaneous injection. This brings down but serum calcium levels revert to previous high in 48 h. So, calcitonin is generally used to prepare the patient for emergent parathyroidectomy. For sus­tained lowering of serum calcium bisphosphates, infusions are given.

combination of nonspecic complaints such as fatigue, bone pain, weight loss, pru­ritis, polydipsia, polyuria, nocturia, joint pain, cardiac dysfunction, constipation, depression, nausea, and hematuria. Because of vivid symptoms related to various systems the diagnosis is often delayed.

Incidence of hypertension in PHPT patients is signicantly high compared to gen­eral population but etiopathogenesis of this association is not completely under­stood. Parathyroid hormone is said to play a permissive role in the hypertensive action of hypercalcemia. Animal studies indicate that chronic hyperparathyroidism

and paraneoplastic hypercalcemia can be instrumental in causing secretion of aldo­sterone ensuing relative hyperaldosteronism. Excess levels of PTH and aldosterone have a damaging effect vessel wall [3]. The resultant vasoconstrictor activity which enhances the renin-angiotensin aldosterone system and probably explains higher frequency of hypertension among patients with PHPT.The resultant vasoconstric­tion and extracellular uid over load may be the pathogenesis of hypertension in PHPT.

Clinical examination does not routinely show any pathognomonic signs. Evidences of target organ damages as deformities, brown tumors and arthritis are not conrmatory of PHPT.Neck swellings closely mimicking thyroid nodules are rare ndings.

2. When hyperparathyroidism is suspected simultaneous estimation of serum cal-

5. Serum 25 OHD estimation is necessary in further management of the PHPT.

7. Bone mineral density studies indicate fracture risk of the patient and is an indica-

9. Assessment of cardiac function is done with ECG and echocardiogram as rou-

Asymptomatic patients who do not fall into the category requiring operation should be reviewed annually. Clinical judgment shall be supported by estimation serum calcium, phosphate, and creatinine. Biannually skeletal screening for bone loss is done by DXA of wrist with lower radius, lumbar spine and hips is suggested. Annual testing for kidney function by estimating 24-h excretion of calcium and creatinine and eGFR estimation. Patients who show disease progression are sug­gested parathyroidectomy.

Advances in imaging technology and estimation of PTH enables surgeon to per­form minimal exploration. Focused parathyroidectomy involves the removal of the only the abnormal parathyroid gland identied by imaging. When the procedure is performed through a 2–4 cm incision, it is generally known as mini­parathyroidectomy. The completeness of removal of all hyperfunctioning glands is ensured by estimating PTH during the procedure. PTH has a short half-life (<5min) and 10min decline of serum PTH to <50% of pre-excision level ensures complete­ness of removal of all abnormal glands [5].

Remote access procedures are extended to parathyroid diseases also and parathy­roidectomy can be performed by endoscopic exploration. With the introduction mini-Gamma probes hand held probes are used for intraoperative guidance (Radio guided parathyroidectomy).

Modications in parathyroidectomy is effectively implemented as a result of advances inlocalization studies.