Obesity is ordinarily associated with low ghrelin levels. The example of a condition where obesity associated with high ghrelin level is:

Ghrelin is an 28 aa peptide produced from stomach. It increases food intake and promotes weight gain. It serves as a signal for initiation of feeding. It inversely corelates with BMI. In obesity ghrelin level are low. EXCEPTION is Prader willi syndrome a genetic obesity syndrome characterized by severe hyperphagia, growth hormone deficiency, hypogonadism. The hyperphagia is due to increased circulating Ghrelin levels. Ref: Sleisenger and Fordtran's, Edition-9, Page-8.