Anorexia nervosa (AN) is an atypical form of malnutrition with peculiar changes in the immune system. We hypothesized that different lymphocyte subsets are differentially affected by malnutrition in AN, and thus, our aim was to investigate the influence of body mass loss on the variability of lymphocyte subsets in AN patients. A group of 66 adolescent female patients, aged 12-17 years, referred for their first episode of either AN or feeding or eating disorders not elsewhere classified were studied upon admission (46 AN-restricting subtype, 11 AN-binge/purging subtype, and 9 feeding or eating disorders not elsewhere classified). Ninety healthy adolescents served as controls. White blood cells and lymphocyte subsets were analyzed by flow cytometry. Relationships with the body mass index (BMI) z score were assessed in linear models adjusted by diagnostic subtype and age. Leukocyte numbers were lower in AN patients than in controls, and relative lymphocytosis was observed in AN-restricting subtype. Lower CD8, NK, and memory CD8 counts were found in eating disorder patients compared with controls. No differences were found for CD4 counts or naive and memory CD4 subsets between the groups. Negative associations between lymphocyte percentage and the BMI z score, as well as between the B cell counts, naive CD4 percentage and counts, and the BMI z score, were found. In conclusion, increased naive CD4 and B lymphocyte subsets associated with body mass loss drive the relative lymphocytosis observed in AN patients, which reflects an adaptive mechanism to preserve the adaptive immune response.

Introduction: Psychological and neuroendocrine alterations are typical characteristics in anorexia nervosa patients. The role of adipokines and cytokines as mediators of body systems' adaptations to the patients' abnormal eating behavior is not well understood. The duration of disease seems to be a determinant of nutritional status and associated hormone changes. We aimed to assess whether alterations in adipokines, cytokines and cortisol do already exist in patients with a recent disease onset by means of a case-control study. Methods: Forty-one adolescent female patients on their first-episode and diagnosed with anorexia nervosa, were matched by age and socioeconomic status (SES) (1:1) with healthy girls.Leptin, soluble leptin receptor (sOB-R), adiponectin, cortisol, and the cytokines IL-1β, IL-2, IL-6 and TNF-α were examined. Results: The results showed reduced leptin and increased sOB-R and cortisol levels in AN patients. Adiponectin was also increased but opposite to the previous biomarkers did not correlate with BMI Z-score. Serum TNF-α and IL-2 showed significantly lower and higher values, respectively, in the AN patients than in the controls. Cortisol showed the strongest correlation with sOB-R (r= 0.436; P=0.005). Conclusions: Our study confirms previous findings on adipokine and cortisol alterations in AN patients, while overall cytokine results did not show a clear disruption in AN patients with short disease duration. The results highlight the need to disentangle the role of the sOB-R in the interactions between leptin and cortisol secretion.Introducción: Las alteraciones psicológicas y neuroendocrinas son típicas de las pacientes con anorexia nerviosa. El papel de las adipoquinas y citoquinas como mediadores de la adaptación del organismo al comportamiento alimentario alterado no es bien conocido. La duración de la enfermedad parece ser un determinante del estado nutricional y de los cambios hormonales asociados. Nuestro objetivo ha sido establecer si existen alteraciones de adipoquinas, citoquinas y cortisol en pacientes con un comienzo reciente de la enfermedad en un estudio caso-control. Métodos: Cuarenta y una chicas adolescentes diagnosticadas con anorexia nerviosa en su primer episodio fueron emparejadas por edad y estado socioeconómico (1:1) con adolescentes sanas. Se midieron leptina, receptor soluble de leptina, adiponectina, cortisol y las citoquinas IL-1β, IL-2, IL-6 y TNF-α. Resultados: Las pacientes con AN mostraron niveles reducidos de leptina y elevados de receptor de leptina y cortisol. La adiponectina también se observó elevada, pero al contrario que los otros marcadores no correlacionó con el Z-score del

Introduction: Psychological and neuroendocrine alterations are typical characteristics in anorexia nervosa patients. The role of adipokines and cytokines as mediators of body systems' adaptations to the patients' abnormal eating behavior is not well understood. The duration of disease seems to be a determinant of nutritional status and associated hormone changes. We aimed to assess whether alterations in adipokines, cytokines and cortisol do already exist in patients with a recent disease onset by means of a case-control study. Methods: Forty-one adolescent female patients on their first-episode and diagnosed with anorexia nervosa, were matched by age and socioeconomic status (SES) (1:1) with healthy girls.Leptin, soluble leptin receptor (sOB-R), adiponectin, cortisol, and the cytokines IL-1β, IL-2, IL-6 and TNF-α were examined. Results: The results showed reduced leptin and increased sOB-R and cortisol levels in AN patients. Adiponectin was also increased but opposite to the previous biomarkers did not correlate with BMI Z-score. Serum TNF-α and IL-2 showed significantly lower and higher values, respectively, in the AN patients than in the controls. Cortisol showed the strongest correlation with sOB-R (r= 0.436; P=0.005). Conclusions: Our study confirms previous findings on adipokine and cortisol alterations in AN patients, while overall cytokine results did not show a clear disruption in AN patients with short disease duration. The results highlight the need to disentangle the role of the sOB-R in the interactions between leptin and cortisol secretion.Introducción: Las alteraciones psicológicas y neuroendocrinas son típicas de las pacientes con anorexia nerviosa. El papel de las adipoquinas y citoquinas como mediadores de la adaptación del organismo al comportamiento alimentario alterado no es bien conocido. La duración de la enfermedad parece ser un determinante del estado nutricional y de los cambios hormonales asociados. Nuestro objetivo ha sido establecer si existen alteraciones de adipoquinas, citoquinas y cortisol en pacientes con un comienzo reciente de la enfermedad en un estudio caso-control. Métodos: Cuarenta y una chicas adolescentes diagnosticadas con anorexia nerviosa en su primer episodio fueron emparejadas por edad y estado socioeconómico (1:1) con adolescentes sanas. Se midieron leptina, receptor soluble de leptina, adiponectina, cortisol y las citoquinas IL-1β, IL-2, IL-6 y TNF-α. Resultados: Las pacientes con AN mostraron niveles reducidos de leptina y elevados de receptor de leptina y cortisol. La adiponectina también se observó elevada, pero al contrario que los otros marcadores no correlacionó con el Z-score del