pica

Pica
Classification and external resources
Stomach contents of a psychiatric inpatient with pica
ICD-10	F50.8, F98.3
ICD-9	307.52
DiseasesDB	29704
eMedicine	ped/1798
MeSH	D010842

Pica (pron.: /ˈpaɪkə/ PY-kə) is characterized by an appetite for substances largely non-nutritive, such as clay, chalk, dirt, or sand.^[1] For these actions to be considered pica, they must persist for more than one month at an age where eating such objects is considered developmentally inappropriate. There are different variations of pica, as it can be from a cultural tradition, acquired taste or a neurological mechanism such as an iron deficiency, or chemical imbalance. It can lead to intoxication in children which can result in an impairment in both physical and mental development.^[2] In addition, it can also lead to surgical emergencies due to an intestinal obstruction as well as more subtle symptoms such as nutritional deficiencies and parasitosis.^[2] Pica has been linked to mental disorders and they often have psychotic comorbidity. Stressors such as maternal deprivation, family issues, parental neglect, pregnancy, poverty, and a disorganized family structure are strongly linked to pica.^{[citation needed]}

Pica is more commonly seen in women and children,^[3] where it affects people of all ages in these subgroups. Particularly it is seen in pregnant women, small children, and those with developmental disabilities such as autism. Children eating painted plaster containing lead may suffer brain damage from lead poisoning. There is a similar risk from eating dirt near roads that existed prior to the phaseout of tetraethyllead in petrol (in some countries) or prior to the cessation of the use of contaminated oil (either used or containing toxic PCBs or dioxin) to settle dust. In addition to poisoning, there is also a much greater risk of gastro-intestinal obstruction or tearing in the stomach.^{[4][unreliable medical source?]} Another risk of dirt-eating is the ingestion of animal feces and accompanying parasites. Pica can also be found in other animals and is most commonly found in dogs.^{[citation needed]}

Signs and symptoms

Chalky stone composed of kaolinite with traces of quartz ingested by a person with pica.

Pica is the consumption of substances with no significant nutritive value such as earth or ice.^[1] Subtypes are characterized by the substance eaten for example:

• Amylophagia (consumption of starch)
• Coprophagy (consumption of feces)
• Geophagy (consumption of soil, clay, or chalk)
• Hyalophagia (consumption of glass)
• Consumption of dust or sand has been reported among iron-deficient patients.
• Lithophagia (a subset of geophagia, consumption of pebbles or rocks)^[5]
• Mucophagia (consumption of mucus)
• Odowa (soft stones eaten by pregnant women in Kenya)^[6]
• Consumption of paint.
• Pagophagia (pathological consumption of ice)
• Self-cannibalism (rare condition where body parts may be consumed; see also Lesch-Nyhan syndrome)
• Trichophagia (consumption of hair or wool)
• Urophagia (consumption of urine)
• Xylophagia (consumption of wood or paper)

This pattern of eating should last at least one month to fit the diagnosis of pica.^[7]

Complications

Complications may occur due to the substance consumed. For example lead poisoning may result from the ingestion of paint or paint-soaked plaster, hairballs may cause intestinal obstruction and Toxoplasma or Toxocara infections may follow ingestion of feces or dirt.^[8]

Diagnosis

There is no single test that confirms pica. However, because pica can occur in people who have lower than normal nutrient levels and poor nutrition (malnutrition), the health care provider should test blood levels of iron and zinc. Hemoglobin can also be checked to test for anemia. Lead levels should always be checked in children who may have eaten paint or objects covered in lead-paint dust. The health care provider should test for infection if the person has been eating contaminated soil or animal waste.^[7]

DSM

1. Persistent eating of nonnutritive substances for a period of at least one month^[9]
2. Does not meet the criteria for either having autism, schizophrenia, or Kleine-Levin syndrome.^[8]
3. The eating behavior is not culturally sanctioned^[9]
4. If the eating behavior occurs exclusively during the course of another mental disorder (e.g., intellectual disability, pervasive developmental disorder, schizophrenia), it is sufficiently severe to warrant independent clinical attention.^[9]

Differential diagnosis

In individuals with autism, schizophrenia, and certain physical disorders (such as Kleine-Levin syndrome), nonnutritive substances may be eaten. In such instances, Pica should not be noted as an additional diagnosis.^[8]

Causes

The scant research that has been done on the causes of pica suggests that the disorder is a specific appetite caused by mineral deficiency in many cases, such as iron deficiency, which sometimes is a result of celiac disease^[3] or hookworm infection.^[10] Often the substance eaten by someone with pica contains the mineral in which that individual is deficient.^[11] More recently, cases of pica have been tied to the obsessive–compulsive spectrum, and there is a move to consider OCD in the etiology of pica.^[12] However, pica is currently recognized as a mental disorder by the widely used Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). Sensory, physiological, cultural and psychosocial perspectives have also been used by some to explain the causation of pica.

It has been proposed that mental-health conditions, such as obsessive-compulsive disorder (OCD) and schizophrenia, can sometimes cause pica.^[13]

However, pica can also be a cultural practice not associated with a deficiency or disorder. Ingestion of kaolin (white dirt) among African-American women in the US state of Georgia shows the practice there to be a DSM-IV "culture-bound syndrome" and "not selectively associated with other psychopathology".^[14] Similar kaolin ingestion is also widespread in parts of Africa.^[15] Such practices may stem from health benefits such as the ability of clay to absorb plant toxins and protect against toxic alkaloids and tannic acids.^[16]

Treatment

Treatment for pica may vary by patient and suspected cause (e.g., child, developmentally disabled, pregnant or psychotic) and may emphasize psychosocial, environmental and family-guidance approaches, (iron deficiency) may be treatable though iron supplement through dietary changes. An initial approach often involves screening for and, if necessary, treating any mineral deficiencies or other comorbid conditions.^[3] For pica that appears to be of psychotic etiology, therapy and medication such as SSRIs have been used successfully.^[17] However, previous reports have cautioned against the use of medication until all non-psychotic etiologies have been ruled out.^[18]

Looking back at the different causes of Pica related to assessment, the clinician will try to develop a treatment. First, there is Pica as a result of social attention. A strategy might be used of ignoring the person’s behavior or giving them the least possible attention. If their Pica is a result of obtaining a favorite item, a strategy may be used where the person is able to receive the item or activity without eating inedible items. The individual’s communication skills should increase so that they can relate what they want to another person without engaging in this behavior. If Pica is a way for a person to escape an activity or situation, the reason why the person wants to escape the activity should be examined and the person should be moved to a new situation. If Pica is motivated by sensory feedback, an alternative method of feeling that sensation should be provided. Other non-medication techniques might include other ways for oral stimulation such as gum. Foods such as popcorn have also been found helpful. These things can be placed in a “Pica Box” which should be easily accessible to the individual when they feel like engaging in Pica.^[2]

Behavior-based treatment options can be useful for developmentally disabled and mentally ill individuals with pica. These may involve using positive reinforcement normal behavior. Many use aversion therapy, where the patient learns through positive reinforcement which foods are good and which ones they should not eat. Often treatment is similar to the treatment of obsessive compulsive or addictive disorders (such as exposure therapy). In some cases treatment is as simple as addressing the fact they have this disorder and why they may have it. A recent study classified nine such classes of behavioral intervention: Success with treatment is generally high and generally fades with age, but it varies depending on the cause of the disorder. Developmental causes tend to have a lower success rate. Pregnancy craving causes tend to have higher success rates.^[19]

Treatment techniques include:^[2]

• Presentation of attention, food or toys, not contingent on pica being attempted
• Differential reinforcement, with positive reinforcement if pica is not attempted and consequences if pica is attempted
• Discrimination training between edible and inedible items, with negative consequences if pica is attempted
• Visual screening, with eyes covered for a short time after pica is attempted
• Aversive presentation, contingent on pica being attempted:

1. oral taste (e.g., lemon)
2. smell sensation (e.g., ammonia)
3. physical sensation (e.g., water mist in face)

• Physical restraint:

1. self-protection devices that prohibit placement of objects in the mouth
2. brief restraint contingent on pica being attempted
3. Time-out contingent on pica being attempted
4. Overcorrection, with attempted pica resulting in required washing of self, disposal of nonedible objects and chore-based punishment
5. Negative practice (non-edible object held against patient's mouth without allowing ingestion)

Epidemiology

The prevalence of pica is difficult to establish because of differences in definition and the reluctance of patients to admit to abnormal cravings and ingestion.^[2] Thusly leading to the prevalence recordings of pica being in the range of 8% and 65% depending on the study.^[1] A study published in 1994 found that 8.1% of pregnant African-American women in the United States self-reported pagophagia, the ingestion of large quantities of ice and freezer frost.^[20] A study conducted in 1991 found a prevalence of pica in 8.8% of pregnant women in Saudi Arabia.^[21] Rates of pica among pregnant women in developing countries, however, can be much higher, with estimates of 63.7%^[22] and 74.0%^[23] reported for two different African populations. This is due to different cultural norms as well as greater levels of malnutrition. Two studies of mentally retarded adults living in institutions found that 21.8%^[24] and 25.8%^[25] of these groups suffered from pica. Prevalence rates for children with and without developmental disabilities are unknown.

History

The term pica originates from the Latin word for magpie, a bird that is reputed because of their unusual eating behaviors where they are known to eat almost anything.^[26] In 13th century Latin work, pica was referenced by the Greeks and Romans; however, it was not addressed in medical texts until 1563.^[3] In the southern United States in the 1800s, geophagia was a common practice among the slave population.^[3] Geophagia is a form of pica in which the person consumes earthly substances such as clay, and is particularly prevalent to augment a mineral-deficient diet.^[27] Research on eating disorders in the 16th century to the 20th century suggests that during that time in history, pica was regarded more as a symptom of other disorders rather than its own specific disorder. Even today, what can be classified as pica behavior is a normative practice in some cultures as part of magical beliefs, healing methods, or religious ceremonies.^[3]

In other animals

Unlike in humans, pica in dogs or cats may be a sign of immune-mediated hemolytic anemia, especially when it involves eating substances such as tile grout, concrete dust and sand. Dogs exhibiting this form of pica should be tested for anemia with a CBC or at least hematocrit levels.^[28][29] However since it may be an evolved natural mechanism to increase micronutrient levels this type of geophagia may not be accurately described as pica since it is not actually a diseased behaviour.

See also

• Michel Lotito
• Tarrare
• Charles Domery

References

External links

• Book chapter