PC2185: The Great Masquerader: The Uncommon Presentation of a Common Pathology

Introduction: Graves disease is a common endocrine diagnosis in both pediatric and adult populations. When presenting with well-recognized manifestations of the disease, patients often receive timely diagnosis and treatment which significantly improves quality of life. Alternately, atypical presentations can lead to costly delays in diagnosis and effective treatment. We present the case of an 18-year-old male who presented with persistent abdominal pain, fatigue, and mild hypercalcemia. His symptoms presented a diagnostic puzzle requiring multiple subspecialty evaluations before finally arriving to the correct diagnosis.

Case Description: The patient is an 18-year-old male who presented with a 4-month history of intermittent, disabling abdominal pain and fatigue. He was initially evaluated in the Emergency Department for abdominal pain with work-up notable for normal abdominal computed tomography and hypercalcemia (10.8mg/dL, ref range (RR) 8.6-10.2). Persistent vague epigastric abdominal pain disrupting daily function prompted a gastroenterology consult. Further evaluation yielded normal inflammatory markers, a normal abdominal ultrasound, and endoscopic biopsies. Hypertension was noted on multiple presentations leading to a nephrology consult. The patient continued to demonstrate hypercalcemia (11.3 mg/dL) with an appropriately low parathyroid hormone (PTH) level and low 1,25 dihydroxy-vitamin D level. Aldosterone, plasma renin activity, plasma metanephrine, and PTH-related peptide levels were normal. Cardiology was consulted for further evaluation of hypertension and newly identified murmur. EKG showed sinus tachycardia and echocardiogram was unrevealing. During this time period, he began endorsing other symptoms including muscle cramps, sleep disturbance, anxiety, waxing and waning appetite, intermittent diaphoresis, palpitations, and occasional nocturia. After 6 months of worsening symptoms, the patient was referred to endocrinology where he was discovered to have a subclavicular goiter, an undetectable TSH level, an elevated free thyroxine level, positive thyroid peroxidase antibodies, and an elevated thyroid stimulating immunoglobulin level. He was ultimately diagnosed with Graves disease and started on methimazole and atenolol for symptomatic improvement. Within 4 weeks, his abdominal pain resolved, calcium level normalized (9.4 mg/dL), and he was able to resume regular activity.

Discussion: Hyperthyroidism can be a “great masquerader” and does not always present with the typical triad of goiter, exophthalmos, and palpitations. Graves disease rarely presents with moderate hypercalcemia resulting in symptoms, and there are no such pediatric or young adult cases documented in the literature. By retrospective chart review, this patient’s presentation suggested hyperthyroidism, but the timing of his symptoms and pathway leading to his diagnosis was unusual. He underwent multiple subspecialty evaluations, extensive imaging, procedures, and laboratory testing. A cost-analysis reveals that a savings of $12,119.13 would have occurred had thyroid function studies been completed during his initial evaluation for weight loss, hypertension, abdominal pain, and hypercalcemia.

Conclusion: This case highlights the importance of considering this common endocrine disorder when unexplained hypercalcemia is present in the setting of other symptoms of thyrotoxicosis.