Nephrology Grand
Rounds
5/13/08
Refractory
Hyperparathyroidism
Brad Weaver
Causes of refractory HPTH



Inadequate therapy
Persistent hyperphosphatemia
Acquired abnormalities of parathyroid gland
Polyclonal cell proliferation (diffuse hyperplasia) –
summative effect of each cell having a
nonsuppressible basal secretion of PTH
 Monoclonal cell proliferation – can lead to
adenomatous cells that do not respond to
appropriate feedback

General indications for
parathyroidectomy






Symptomatic patients with elevated and
nonsuppressible iPTH (usually >800)
Hyperparathyroid bone disease – diagnosed by
radiographical evidence or bone biopsy
Extensive extraskeletal calcifications or
calciphylaxis
Refractory pruritis
Unexplained myopathy
Severe hypercalcemia (mainly seen in primary
HPTH)
Effects of parathyroidectomy
Effects cont.


Parathyroidectomy may have beneficial effects
on humoral immunity
Prospective study 1999: 34 dialysis patients
received parathyroidectomy for 2°HPTH.
At 12 months there were significant increases in
serum levels of IgG, IgM, IgA, C3, C4, and CH50
 Nutrional status also improved as measured by
significant increases in albumin and hematocrit

Am J Surg 1999 Oct;178(4):332-6.
VA Study 2004 – U. of Washington




Observational matched cohort study of 4558
dialysis patients undergoing parathyroidectomy
vs. 4558 matched controls
Higher 30 day mortality in parathyroidectomy
group 3.1% vs. 1.2% in controls
Long term survival better in parathyroidectomy
group – 53 vs. 47 months
Survival curves crossed at 587 days s/p surgery
Kidney Int 2004 Nov;66(5):2010-6
Parathyroidectomy and transplant

What to do with a patient with refractory
hyperparathyroidism on transplant list?
Most cases (approximately 96%) of HPT resolve
after transplant
 HPT that does not resolve may cause increased risk
to the renal graft and may cause hypertension
 However, parathyroidectomy in transplant patients
carries a small risk of sudden deterioration of renal
graft function

Surgical considerations

In primary HPTH, nuclear medicine scans
(technetium-99m-sestamibi or I-123 SPECT) are
used to detect location of glands prior to
surgery



Unknown if useful in 2°HPT due to renal failure
Total parathyroidectomy with
autotransplantation is the most common
technique
Reoperation rates for persistent HPT are 6-14%
Hungry bone syndrome




Severe hypocalcemia following
parathyroidectomy in spite of normal or
elevated PTH levels
Sudden decrease in PTH disrupts bone
equilibrium of resorption vs. formation
Most common in patients with severe
preexisting bone disease
Occurred in 20% of 148 dialysis patients
undergoing parathyroidectomy in one series
Kidney Int Suppl 2003 Jun;(85):S97-100
Hungry bone syndrome cont.



Hypocalcemia
 Nadirs 2-4 days post op
 If tetany and seizures occur, they can increase
fracture risk
 Sudden heart failure has been attributed to
hypocalcemia
Hypophosphatemia and hypomagnesemia
 Mainly seen in primary HPTH
Hyperkalemia
 Occurs in 80% of dialysis patients post-op
Treatment





Oral calcium – 2 to 4 g per day
IV calcium for symptomatic hypocalcemia or Ca <
7.5 – 1 amp of calcium gluconate instilled over 10
to 20 minutes followed by maintenance drip
Vitamin D supplementation – calcitriol
Hemodialysis – use high calcium bath (3.5 mEq/L
Ca)
Peritoneal dialysis – add 1 to 3 amps of calcium
gluconate to each bag of dialysate