Abstract

Obesity commonly occurs as a result of environmental polygenic factors but it can be caused by a number of nonenvironmental non-polygenic conditions, the so called monogenic forms of obesity, which are rare causes of obesity, the treatable form of which is congenital leptin deficiency which is a clinical condition that arises due to genetic loss of leptin functions. It is distinguished by an early onset severe obesity as a result of uncontrolled appetite. Despite the fact that it is a rare condition, patients respond well to leptin replacement therapy.
Methods: In this review, data on the effects of leptin analogue was extracted from naïve leptin patients and six studies were included.
Results: As an overall trend leptin therapy has a powerful positive effects on body weight and associated abnormalities, a remarkable weight loss was observed among participants (mean weight reduction was 29.6 kg), reported cases were fifteen for LEP gene defects, twenty-one for LEPR gene mutations and three for functional leptin mutations.
Conclusion: This review will assess congenital leptin deficiency condition in terms of phenotypes, clinical consequences, diagnosis and management, and will evaluate leptin analogue therapy among different genetic phenotypes of leptin deficiency patients.

Keywords: Leptin, Congenital leptin deficiency, Lepr, Obesity, Metreleptin