Primary Hyperparathyroidism Presenting as Posterior Reversible Encephalopathy Syndrome: A Report of Two Cases

Abstract

What is already known on this topic? Hypercalcemia, mostly severe hypercalcemia secondary to malignancies, has been rarely implicated in the causation of posterior reversible encephalopathy syndrome (PRES). Primary hyperparathyroidism (PHPT) is usually associated with mild-moderate hypercalcemia and has rarely been implicated in PRES. What this study adds? Herein we have reported two cases of adolescent primary hyperparathyroidism presenting as PRES. We propose that serum calcium levels should be checked in all patients with PRES and PHPT be regarded as a differential diagnosis in those with underlying hypercalcemia.

Hypercalcemic crisis caused by primary hyperparathyroidism in a 11-year-old boy: a rare case report and review of the literature

“…In two cases (cases 4 and 5), bilateral neck exploration was performed, but the glands other than the responsible one were preserved because they were of normal size. The serum intact-PTH levels decreased to normal levels soon after the surgery (9). Furthermore, in all the cases shown in Table 1, the resected gland was histopathologically diagnosed with adenoma.…”

“…However, because PHPT is likely to be symptomatic in pediatric patients, even if the symptoms are vague, it is usually diagnosed before hypercalcemic crisis is developed. Indeed, there are only six reports of PHPT-induced hypercalcemic crisis in pediatric patients (7)(8)(9)(10)(11). Thus, an appropriate treatment approach for this condition has not been demonstrated.…”

“…Because it is necessary to lower serum calcium levels, the initial treatment consisting of normal saline infusion and/ or furosemide was immediately started for all six patients shown in Table 1. However, bisphosphonate (etidronate, pamidronate, or zoledronate) was used to decrease serum calcium levels in four out of six cases (7,(9)(10)(11), while in one case, denosumab, a human monoclonal antibody of the receptor activator of nuclear factor kappa-B ligand, was administered (8). In addition, calcitonin was used in one case (7).…”

“…With regard to other anti-bone resorption agents, cinacalcet, which is currently used to treat secondary hyperparathyroidism and parathyroid carcinoma, can be an option in the future. Although serum calcium levels were decreased by these medical treatments to some extent, parathyroidectomy was performed as radical treatment soon after hospitalization (1-5 days after admission) in five out of six patients (7,(9)(10)(11). Another patient (case 6) underwent surgery 22 days after admission.…”