nnavam wrote:
Q#29

A 43-year-old woman with a recent diagnosis of B-cell lymphoma is being evaluated for chemotherapy. She is hospitalized because of fatigue, dizziness, polyuria, and constipation. She fell at home while trying to get out of bed. On physical examination, she is orthostatic and pale. The hematocrit is 38%, blood urea nitrogen 65 mg/dL (23.21 mmol/L), creatinine 2.5 mg/dL (221.05 µmol/L), and calcium 12.8 mg/dL (3.19 mmol/L). Intravenous fluid resuscitation with normal saline is initiated.

Which of the following is the most appropriate next test in the evaluation of this patient?
1)Parathyroid hormone (PTH)
2)Parathyroid hormone–related peptide (PTHrP)
3)1,25-dihydroxyvitamin D3
4)25-hydroxyvitamin D

1,25-dihydroxyvitamin D3

This hormone is made by some lymphoma cells.

nnavam wrote:
Q#30

A 44-year-old woman is evaluated for fatigue, polyuria, and constipation of 2 years' duration.
She has not seen a physician in years because of lack of medical insurance. Laboratory evaluation reveals hypercalcemia, hypophosphatemia, elevated parathyroid hormone level, and increased markers of bone turnover.
Subperiosteal bone resorption of the distal phalanges, femoral and spine osteopenia, and osteoporosis in the radius are found.
A parathyroid sestamibi scan localizes parathyroid adenoma to the right upper neck; the adenoma is removed by minimally invasive parathyroidectomy. Postoperatively, profound hypocalcemia and hypophosphatemia with tetany develop. The simultaneous parathyroid hormone level is <5 pg/mL (5 ng/L). The hypocalcemia requires therapy with large doses of intravenous and later orally administered calcium and vitamin D to relieve her symptoms and normalize the serum calcium and phosphate concentrations.

Which of the following is the most likely diagnosis?
1)Permanent surgical hypoparathyroidism
2)Temporary hypoparathyroidism due to vascular insufficiency
3)Hungry bone syndrome
4)Vitamin D deficiency
5)Osteomalacia

Hungry bone syndrome. More common in end-stage renal disease-related tertiary hyperprathyoridism

Q#25

Which of the following diagnostic studies is most appropriate for this patient?
1)24-Hour urine collection for proteinuria
2)Kidney ultrasonography
3)Measurement of urine microalbumin
4)Measurement of hemoglobin A1c[/quote]

A strange question. Not sure where they are going with this. But if this were real life, I might say that the decrease in renal function is rather sudden and in the absence of a history of heavy proteinuria, would worry about something in the urinary tract. So I select U/S., #2[/quote]


"in the absence of a history of heavy proteinuria"...,We do not know anything about his proteinuria from the Question....other than is already on ACEI.

Screening test for diabetic nephropathy....1 vs 3.

Its Measurement of urine microalbumin.

A 24-hour urine collection is no longer recommended to assess kidney function or quantify proteinuria.

Q#26
A 28-year-old woman is evaluated for a serum calcium level of 2.74 mmol/L obtained during a routine physical examination.
All other laboratory values are normal.
PTH level was subsequently checked and is 40 ng/L.
The patient is healthy and has no symptoms of polyuria, constipation, or fatigue.
Her mother and maternal grandfather have a history of hyperparathyroidism, and they both underwent parathyroidectomy but remained mildly hypercalcemic.
The patient had a recent renal ultrasound that showed no evidence of nephrolithiasis. Her diet is rich in dairy products, and she has no history of gastrointestinal illness.

Which of the following tests would be most likely to confirm the diagnosis?

1)25-hydroxyvitamin D
2)1,25-Dihydroxyvitamin D
3)Urine calcium/creatinine clearance ratio
4)Parathyroid hormone–related peptide[/quote]

3)Urine calcium/creatinine clearance ratio

I wonder about familial hypocalciuric hypercalcemia.[/quote]


In an asymptomatic patient with mild hypercalcemia and an inappropriately normal parathyroid hormone level, the main differential includes:
primary hyperparathyroidism versus benign familial hypocalciuric hypercalcemia.

It is diagnosed by a urinary calcium/creatinine clearance ratio <0.01 measured in a fasting morning urine spot collection.

Rare autosomal dominant disorder characterized by lifelong, mild asymptomatic hypercalcemia.
prevalence is about 1/16,000.
caused by an inactivating mutation of the calcium-sensing receptor.

Q#27

A 46-year-old woman is evaluated for a serum calcium concentration of 2.84 mmol/L discovered on routine screening.
A dual-energy x-ray absorptiometry showed T scores at the lumbar spine and left femoral neck of −0.88 and −0.05 respectively. There is no history or evidence of renal stones, bone fracture, cognitive impairment, or fatigue.
The intact serum parathyroid hormone level is 115 ng/L. The serum creatinine is 0.9 mg/dL (79.58 µmol/L). The urine calcium/creatinine clearance ratio is greater than 0.01, but the 24-hour urine calcium excretion is 6.3 mmol.

Which of the following is the most appropriate next step in the management of this patient? and Why????
1)Observation
2)Intravenous pamidronate
3)Mammography
4)Parathyroidectomy
5)Low-calcium diet[/quote]

4. Parathyroidectomy for hyperparathyroidism especially is there is an adenoma. Could make a case for observation but she already has decreased bone density.[/quote]

It's 4.

The indications for parathyroidectomy in a patient with mild, asymptomatic hypercalcemia secondary to primary hyperparathyroidism are:(National Institutes of Health's recommendations )
1) age less than 50 years.
2)serum calcium level >1.0 mg/dL (0.25 mmol/L) above the upper limit of normal.
3)24-hour urine calcium excretion >400 mg (10 mmol).
4)creatinine clearance reduced by ≥30%.
5)a bone mineral density T score <2.5 at any site.

The cause of primary hyperparathyroidism in most cases is a single parathyroid adenoma.

UKAdmin wrote:
nnavam wrote:
Q#28

A 48-year-old man is evaluated for weakness and fatigue. He has a history of hypertension and gout.
Medications include ramipril, hydrochlorothiazide, and colchicine.
Social history is significant for having lost his job 2 years ago, after which he has been drinking beer and wine every day. He does not have episodes of delirium tremens but admits to feeling guilty about his alcohol intake.

Physical examination reveals a disheveled man in no acute distress. The blood pressure is 135/80 mm Hg, and pulse rate is 78/min. Chvostek's sign is positive on the right. The liver is palpated 3 cm below the right costal margin and is tender to palpation. No spider angiomata or palmar erythema is noted.

Lab:Hematocrit 33%, Sodium 133 mmol/L, Potassium 3.4 mmol/L, BUN 8.93 mmol/L,
Creatinine 106.1 µmol/L,
Alanine aminotransferase 50 U/L, Aspartate aminotransferase 110 U/L
Alkaline phosphatase 55 U/L
Albumin 35 g/L, Calcium 1.8 mmol/L.

Which of the following is the most appropriate next test in the evaluation of this patient?
1)Parathyroid hormone
2)25-hydroxyvitamin D
3)1,25 hydroxyvitamin D3
4)Phosphate
5)Magnesium

5. Magnesium, hypomagnesemia could precipitate hypocalcemia.

Hypomagnesemia in alcoholics mimic hypoparathyroidism, causing severe hypocalcemia and hyperphosphatemia.

Hypomagnesemia causes hypocalcemia in 2 ways:
1) suppression of PTH secretion.
2) resistance to PTH action.