Mimi is an 11-year-old girl in special education classes brought in to see her pediatrician by her father with a note from the school that says “child is eating paper towel in the bathroom.” Dr. Newman has been Mimi’s pediatrician since she was an infant. Mimi has always been a small child, but she had fallen farther below the average growth curve for height and weight since age 9. Mimi’s father states he does not know what this is about and is only here because the school “tells me I have to bring her in.” He states that he and Mimi’s mother are not together, but he is still involved in Mimi’s life. He works nights, while her mother works during the day. He reports that he had never heard that Mimi had been eating paper towel and thinks it might be a “mistake.” Mimi walks home from her school on her own (4 blocks away). She is supposed to stay with her neighbor and the neighbor’s children until her mother comes home at 6 p.m. Upon further questioning, Mimi’s father states that he once saw her picking up wet sand from a bucket in the playground and putting it into her mouth; he told her to stop doing this. Later in the evaluation, he tells Dr. Newman that he also now recalls that during a visit with her last week, he noted that it looked like she “threw up in her mouth” a few times. He reports that he asked her whether she was feeling sick and she said no and denied having vomited.

Mimi is very quiet in the evaluation room, mostly shaking her head “no” to the questions Dr. Newman asks; she simply looks at him when he asks her about eating paper towels at school or at home. Her examination is largely unremarkable, other than a weight that has not increased since her last well-child visit five months prior, and a sense of fullness in the epigastric area and right upper quadrant. There is no evidence of physical trauma.

Mimi may have a diagnosis of pica .

Pica is a disordered eating behavior in which individuals repeatedly eat non-nutritive substances for a duration of at least one month in a manner that is not consistent with developmental stage or a socially sanctioned practice, and not thought to be better explained by an another psychiatric disorder or medical condition [see Text Box: Pica: DSM-5 Criteria]. Thought to be more common in those with intellectual impairment or nutritional deficiencies (specifically iron), the overall prevalence of pica has not been clearly determined. Pica usually develops during childhood, though may persist into adulthood or may have onset in adulthood. Pica may present during pregnancy. Patients with pica may eat a variety of substances, including soil, paper, paint, and soap. It has been postulated that iron deficiency triggers ingestion of substances such as soil/dirt, and some studies have demonstrated iron deficiency in individuals with pica. This theory has flaws, however; low iron in these patients may be a result of the pica behavior (i.e., eating non-nutritive substances rather than food), not the cause, and the ingestion of substances that do not contain vitamins and other nutrients is not consistent with an adaptive response to a nutritionally deficient state. Patients will sometimes describe a craving for certain non-food items. Complications of pica include impaired nutrition and weight loss if the ingestion of non-food substances replaces a substantial amount of a person’s usual food intake. Those patients who repeatedly ingest substances containing dangerous compounds may develop toxicity (e.g., lead toxicity in children eating lead-based paint). Gastrointestinal problems are also common, including irritation of the gastrointestinal tract from the substance being eaten, or even frank obstruction if the substances being eaten cannot be easily passed. Of note, pica is separate from the disordered behavior of swallowing dangerous items in order to self-injure (such as razor blades and batteries). In addition, if pica symptoms are present in an individual with another major mental disorder (such as autism spectrum disorder—a group of patients in whom pica symptoms are more prevalent), the diagnosis of pica should only be made if the symptoms are considered significant enough to warrant additional clinical attention.