POMC and obesity due to melanocortin 4 receptor deficiency: Her sister (patient B) presented at age 3 years with a similar clinical picture: primary hypocortisolism (serum cortisol < 28 nmol/L) with high plasma ACTH levels (1036 pmol/L), early-onset obesity (at age 3 her weight and height were > 2 SDs above the average, at age 16 her body mass index was 30.3) and hyperphagia, but also an autism spectrum disorder and mild cognitive impairment.