Role of obesity and adipose tissue-derived cytokine leptin during Clostridium difficile infection

• Obesity is associated with an increased risk of Clostridium difficile infection.
• Role of obesity in C. difficile disease outcomes needs further investigation.
• High serum leptin levels are seen in obese individuals.
• Leptin enhances colonic inflammation after C. difficile infection.
• Lack of leptin signaling alters indigenous host microbiota.

Obesity is among the most pressing health concerns in the world since it is increasingly common even in the developing world, and is clearly associated with increased risk for chronic debilitating diseases and death. Furthermore, obesity can influence the pathogenesis of infectious diseases by affecting the balance of pathogen clearance and pathological inflammation. The mechanisms that result in enhanced inflammation in obese individuals are poorly understood. Clostridium difficile is a major cause of nosocomial infections worldwide. Recent studies have shown that obesity is associated with increased risk of C. difficile infections. In this review, we will discuss our current knowledge of the role of obesity in determining risk of C. difficile infections, and focus on the role of the adipose tissue-derived cytokine leptin in C. difficile infections.