Risk of infection and immune function in anorexia nervosa

The eating disorder, anorexia nervosa, like other forms of starvation, has been associated with an increased risk and severity of infectious diseases. However, there is conflicting evidence about the true risk of infection in anorectic patients. Indeed, some anorectics appear to be less susceptible to minor viral illnesses, possibly analagous to the attenuation of viral infections observed in protein‐starved mice. Leukopenia and neutrophil dysfunction, including abnormal chemotaxis and depressed microbicidal activity, have been well documented in some anorectic patients. Abnormalities of the complement system and impaired immunoglobulin synthesis have also been reported. Patients with severe anorexia nervosa are often anergic to skin testing but other abnormalities in cell‐mediated immune function have been difficult to document. Increased spontaneous tumor necrosis factor (TNF) production by peripheral blood mononuclear cells and lower cell‐mediated cytotoxicity have been reported in patients with anorexia nervosa. Further studies are needed to define the true risk of infection in anorexia nervosa and to clarify the types and extent of immune system abnormalities in this patient population.