A 28-year-old male with a history of untreated Wolf-Parkinson disease diagnosed in childhood.
It began in December 2000, with tetraparesis of proximal predominance and kalemia of 2.0 meq/l, with no evidence of renal tubulopathy or intestinal malalignment.
Thyroid function revealed a pattern compatible with primary hypothyroidism [TSH: 12.8 ulU/ml, T3: 160 ng/dl, T4: 6.2 μg/dl, antithyroid antibodies L-)
Tetraparesis reappeared in January 2001, with kalemia of 1.9 meq/l and supraventricular tachyarrhythmia, so electrofulguration was performed.
With a diagnosis of hypokalemic periodic paralysis, propranol 20 mg q12h was initiated and her cardiologist requested PTH, which was 718 pg/ml (VN: 7 to 53 pg/ml), without a known foundation.
Cervical ultrasound showed 4 enlarged parathyroid glands, greater than 7.8 x mm, which was referred to an endocrinologist.
The directed interview did not reveal symptoms of hypocalcemia, intestinal transit alterations, bone pain or fractures.
Physical examination revealed a proportionate male habit.
Talla 1,68 m.
Weight: 81.3 kg. BMI: 28.8 kg/m.
BP: 110/70 mmHg, HR 72 x min regular.
The facies were normal.
Thyroid plaque was normal in shape, size and consistency.
Brachydactyly was not found and Chvostek and Trousseau signs were negative.
Both the eye fundus and pupil red were normal, as well as the intellectual level.
Table 1 shows the initial tests of the patient, highlighting repeated hypocalcemia of 7.9 and 6.7 mg/dl (adjusted according to albuminemia) in concomitance with PTH of 1.343 and 1.101 pg, respectively.
Both renal function and magnesemia were normal.
To rule out secondary hyperparathyroidism, calciuria of 24 h and 25 0H vitamin D were measured, which resulted in normal and slightly low ranges, respectively.
It was not possible to measure 1.25 OHD, a test that is not performed in Chile.
the left femoral hypoparathyroidism score2, and as a way to evaluate PTH resistance to PTH, measured bone fraction in normal controls (local measured at T = 1.079, and femoral neck at L2-L4: 1.179).
However, increased markers of exchange, urinary hydroxyproline and osteocalcin showed some degree of bone response to such high concentrations of PTH.
Hand radiography showed no abnormalities suggestive of Albright osteodystrophy (brachydactyly, microphalanges, tapering of 4° or 5° distal metatarsal).
1.
To demonstrate renal tubular resistance to PTH, tubular reabsorption of phosphates was measured, which, despite high PTH values, was 92%.
It is usually less than 80% in hyperparathyroidism.
The measurement of other hormones whose action is mediated by G protein ruled out resistance to radiation, although the patient had a history of elevated TSH in the absence of goiter or antithyroid antibodies.
The patient was treated with calcitriol at doses of 1 to 2 ug/d, associated with 2 g/day of calcium, which normalized calcemia at two months and PTH at six months.
The control showed ultrasound disappearance of the parathyroid glands visualized at the time of diagnosis.
Once TSH and calcemia levels have normalized, the patient has not repeated episodes of hypokalemic paralysis.
The biochemical study of calcemia, sickle cell anemia and PTH of their parents and sister was normal.
