What is Russell's sign associated with?

Russell's sign is specifically associated with calloused knuckles that result from repeated trauma caused by self-induced vomiting, a behavior commonly seen in individuals with bulimia nervosa. When a person forces themselves to vomit, the back of the hand may repeatedly come into contact with the teeth, leading to calluses or abrasions on the knuckles. This physical sign serves as a potential indicator of an eating disorder, particularly bulimia, and highlights the longer-term consequences of such behaviors.

The other options relate to different aspects of eating behaviors or conditions but do not connect directly to Russell's sign. Severe weight gain is more associated with binge eating disorders, while weight loss through exercise does not pertain to the physical manifestations indicative of self-induced vomiting. Excessive salivary production is often seen in other contexts, such as anxiety or certain medical conditions, rather than being specifically linked to the behavioral patterns of bulimia or the resulting physical signs like Russell's sign.