Bulimia nervosa patient diagnosed with previously unsuspected ADHD in adulthood: clinical case report, literature review, and diagnostic challenges

There is increasing literature suggesting a link between attention-deficit hyperactivity disorder (ADHD) and eating disorders (EDs), especially bulimia nervosa. ADHD is under-diagnosed in girls and children of high intelligence are typically missed. We identified a case of a 23-year-old woman suffering from severe bulimia nervosa and previously unsuspected ADHD in adulthood; we diagnosed and treated her with extended-release methylphenidate. We performed a literature review on the ADHD and bulimia nervosa comorbidity. We discuss the reasons why her ADHD remained undiagnosed and the difficulties in diagnosing ADHD in patients with EDs. We suggest that identifying comorbid ADHD is crucial for these patients and argue for the use of a structured interview, collateral history and investigation of onset of symptoms to establish a diagnosis of ADHD in adults with bulimia nervosa. Comorbidities and overlap of symptomatology need to be taken into account.