Eur Child Adolesc Psychiatry (2009) 18:645–651 Table 4 Adapted diagnostic criteria for PRS Diagnostic criteria for pervasive refusal syndrome A. Partial or complete refusal in three or more of the following domains: (1) eating, (2) mobilization, (3) speech, (4) attention to personal care B. Active and angry resistance to acts of help and encouragement C. Social withdrawal and school refusal D. No organic condition accounts for the severity of the degree of symptoms E. No other psychiatric disorder could better account for the symptoms F. The endangered state of the patient requires hospitalization disorders [11]. Table 5 presents an overview of the most common differential diagnoses. None of these diagnoses, however, accounts for the whole variety of symptoms seen in PRS, as described in detail by Bryan Lask (vide infra) [11]. Moreover, the active resistance to any form of help is the distinguishing feature of PRS. Although many of the features of PRS are compatible with a diagnosis of depression, common features of a severe major depressive episode such as psychomotor slowing, a constantly depressed mood and sleep disturbance are uncommon in PRS [11]. Anxiety can be seen in children with PRS, but an anxiety disorder does not account for the whole range of symptoms seen in PRS. Both depression and anxiety can be seen as comorbid to PRS. Food refusal is often seen in PRS, but in general the refusal is neither particularly focused on nor exclusive to food [11]. It is motivated by a desperate need to refuse and not by a desire to lose weight. A diagnosis of eating disorder is therefore not applicable. Selective mutism and school refusal refer to a speciﬁc area of functioning, while the refusal seen in PRS is far more pervasive. Chronic fatigue is common in PRS, but by no means the most central feature. Children with chronic Table 5 Main differential diagnoses of PRS (n = 24)a, 1991–2006 a Twenty-three patients from the literature search ? 1 patient from the Dutch article [25] Main differential diagnoses Depression Somatoform disorder Anxiety disorder Eating disorder Chronic fatigue syndrome Factitious disorder Catatonic disorder/stupor Selective mutism Frequency (total n = 24) 13 (54%) 10 (42%) 7 (29%) 4 (17%) 1 (4%) 1 (4%) 1 (4%) 1 (4%) 649 fatigue syndrome show very few of the other symptoms of PRS and are frustrated with their ill-health and have a strong wish to recover [11], in contrast to children with PRS. In our case report, the main differential diagnosis was factitious disorder, in contrast to most of the other pub- lished cases (see Table 5). A depressed mood was not found and Kate did not seem anxious at all. She showed situation-speciﬁc physical symptoms that had a strong intentional character, which ruled out a somatoform dis- order. Her complaints seemed to ﬂuctuate, particularly worsening when parents or medical/nursery staff were present, indicating either a factitious disorder or malin- gering. A diagnosis of malingering could be excluded because external incentives for her behaviour were not found and were explicitly denied by both Kate and her parents. Factititious disorder was considered but is typi- cally characterised by help-seeking behaviour and not by an active resistance to help, as seen in our patient. Regression has never been mentioned as a differential diagnosis of PRS in literature. We, however, consider regression as strongly correlated with PRS. In our opinion, and based on the above-mentioned deﬁnitions, refusal, withdrawal and regression can be considered different states of the same spectrum, with refusal being the less severe variant and regression the most severe (see ‘‘Psy- chopathological consideration’’). A waxing and waning from one state into the other and back again is possible, as is a co-existence of the various states of the RWR spec- trum. In PRS, for example, the refusal leads to an increasingly extended social withdrawal. However, as the patient becomes more withdrawn, the refusal remains present. Regression must be considered a more severe and mostly passive state of being with a massive loss of age- adequate psychological functioning. This is partially in contrast to PRS, where active resistance is much more dominant. As regression is mostly seen as a part of an axis- I disorder, PRS is considered an entity in its own right. However, the pervasive refusal and active resistance, which are so characteristic of PRS in children, can also be present in adult patients with an axis-I disorder (e.g. severely ill psychiatric patients with anorexia nervosa, a major depressive disorder or a schizophrenic psychosis who show a pervasive refusal and withdrawal from daily life, as well as an active resistance to treatment and who have been involuntary admitted under the mental health act). In line with the aforementioned, the presentations of the RWR spectrum can be seen as an end point in intensity of many untreated—and sometimes even treated—psychi- atric disorders. In contrast to PRS, which is only identiﬁed in children, regression is most often seen in adults with an axis-I dis- order. It can, however, also affect children. 123