A 26-year-old African-American woman, United States Marine stationed in Japan, was referred for evaluation of failure to gain weight. She reported no complaints and was able to successfully complete military physical fitness requirements without difficulty. Review of systems was notable for spontaneous bilateral epistaxis averaging once monthly, without hematuria. She denied shortness of breath or chest pain. Family history did reveal epistaxis in her mother. Exam was notable for a thin, slender body habitus, BMI 17.5, and room air pulse oximetry of 92%.