Clinical Case Reports

Biography

Biography: Aysha Habib Khan

Abstract

Patients with parathyroid hormone (PTH) disorders develop osteoporosis faster regardless of age or sex. Osteoporosis is often extreme with pain and decrease life expectancy. Diagnoses are challenging in asymptomatic stage due to variable/atypical presentation, lack of awareness and difficulty in interpretation of findings. We reviewed laboratory results of 534 subjects and medical records of 111 subjects tested with bone health screening panel (comprising of serum 25OHD, calcium, phosphorus, magnesium, and alkaline phosphatase, creatinine, albumin and plasma iPTH) in identifying disorders of parathyroid gland secretion. Subjects were classified into groups using lower and upper cutoff of the reference range of biomarker. PTH nomogram by Harvey et al was applied to calculate max PTH in subjects with atypical presentations (normocalcemic hyperparathyroidism and hypercalcemia with inappropriately normal PTH) to determine primary high PTH secretion. Means of iPTH of 534 subjects was high, vitamin D was insufficient, and other markers were in normal range. High creatinine was found in 7% subjects. PTH disorders were classified after excluding high creatinine. The compensatory response of parathyroid gland (secondary hyperparathyroidism) to vitamin D deficient group was seen in 17.7% while 39%, 8%, 1% and 0.4% had functional hyperparathyroidism, normocalcemic hyperparathyroidism, primary hyperparathyroidism and primary hypoparathyroidism respectively. Symptoms of generalized myalgia, bone and joint pains were predominant findings in 111 cases. Parathyroid adenoma, osteopenia/osteoporosis, fractures proximal myopathy and renal stones were seen with deranged parathyroid hormone levels. All subjects with primary hyperparathyroidism and normocalcemic hyperparathyroidism had higher PTH levels than calculated maxPTH. In subjects of hypercalcemia with inappropriately normal PTH, 6 had low, 2 had equal and 2 had high PTH, which was > maxPTH. A significant number of patients presents with biochemical variables that do not fit the classic description of primary and secondary disorders of PTH secretion and may present a diagnostic dilemma. Vitamin D deficiency and insufficiency has an important role in the interpretation of diagnostic tests. A low reference range of PTH has been proposed in vitamin D deficient patients with osteopenia or osteoporosis, to facilitate the diagnosis of mild hyperparathyroidism. Use of a multidimensional nomogram to distinct between normal and disease phenotypes can be used to enhance diagnostic accuracy in atypical cases. There is a dire need to identify the defects in areas with endemic vitamin D deficiency due to its implications on osteoporosis