Anorexia nervosa is a psychiatric disorder with a prevalence of circa five percent in young women population, with an increased tendency of frequent occurrence over the past twenty years. Although the diagnosis is relatively simple and straightforward, the treatment of these patients is often time-consuming and challenging for clinicians, as the occurrence of malignant and persistent forms of the condition is becoming ever more common. Resistant clinical diagnoses usually arise through comorbidity with other psychiatric disorders. Counted among them, first of all, are personality disorders.

A.N. is treated by means of using various groups of psychopharmacological drugs in combination with psychotherapeutic treatment, with intention to establish a favorable therapeutic relationship and stability of the patient. Psychotherapeutic part of the treatment gains in importance when the condition occurs in comorbidity with personality disorders. Supportive treatment measures, namely aggressive rehydration, caloric values compensation via probes and and catheters are often an integral part of the treatment, and become particularly important when faced with treating malignant forms of the condition.

Presented case will show that the malignant forms of Anorexia Nervosa can only be understood through insight into the psychological foundations of personality and frequently accompanying disorders on Axis II (DSM-IV). The female patient in question displays a base borderline personality structure with dominant narcissistic tendencies which prompted the development of a malignant form of the condition and thus made the treatment significantly more difficult. Only early intervention with emphasis on the psychotherapy treatment can ensure a better long-term prognosis in such cases.