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Editor-In-Chief: C. Michael Gibson, M.S., M.D. ; Associate Editor(s)-in-Chief: Maryam Hadipour, M.D.
Synonyms and keywords: Pica syndrome, geophagia eating disorder, geophagy
- Pica is derived from the Latin word 'pica pica' which means magpie, a bird known for its behavior of gathering and eating almost everything.
- It was first documented in the 13th century in Latin work of Bartholomeus de Glanville, although the actual term was not used.
- The first time term ‘Pica’ was mentioned in a medical context was in 1563 in a surgical work, ‘An Excellent Treatise of Wounds made with Gonne Shot’, by Thomas Gale, where pica was addressed in pregnant women and children.
- Historically, clay ingestion had been used for medical purposes probably due to its effect on gastrointestinal (GI) system. It was particularly suggested as a treatment of intestinal infection and spasm.
Pica may be classified according to the name of the eaten substance; the most common types by far are geophagia and amylophagia:
- Acuphagia (sharp objects)
- Amylophagia (purified starch)
- Cautopyreiophagia (burnt matches)
- Coniophagia (dust, dirt)
- Coprophagia (feces)
- Emetophagia (vomit)
- Geomelophagia (raw potatoes)
- Geophagia (earth, soil, clay, chalk)
- Hyalophagia (glass)
- Lithophagia (stones)
- Metallophagia (metal)
- Mucophagia (mucus)
- Pagophagia (ice)
- Plumbophagia (lead, paint chips)
- Trichophagia (hair, wool, fibers)
- Urophagia (urine)
- Hematophagia (blood)
- Xylophagia (wood, paper)
- Hyalophagia (glass)
- Ryzophagia (raw rice)
- Sapophagia (soap)
The exact pathogenesis of Pica is not fully understood. However, there are different theories on developing Pica:
- Children with anemia and low plasma zinc levels may develop Pica and crave for substances rich in the insufficient nutrients.
- Kaolinite, a clay mineral, which has negative surface charge commonly ingested in Pica and can absorb the ions with positive surface charge, such as iron and causes iron-deficiency anemia. 
- There is not enough evidence to determine whether Pica is the cause of nutritional deficiency or nutritional deficiency leads to Pica development. 
Geophagia causes increase in gastrointestinal PH. This effect can soothe gastric pain and gastroesophageal reflux disease. It also results in reduction of bioavailability of pathogens and toxins in gastrointestinal tract, a phenomenon on which a hypothesis is based. The hypothesis states that non-nutritive substances bind to toxins and lead to less toxins absorption. This event occurs in the most vulnerable period of cell replication and growth (childhood and pregnancy) in order to protect the body from dangerous toxins.
- Various human studies revealed that lesions in eating center of hypothalamus and anterior cingulate gyrus may lead hyperphagia and Pica especially in individuals with history of brain damage.
- Animal studies indicated that rats with iron deficiency anemia have fewer D2 receptors in the central nervous system (CNS). This proposes a theory stating that reduction of dopaminergic neurotransmission leads to development of Pica, and not the iron deficiency anemia.
A hypothesis states that Pica can be attributed to obsessive-compulsive spectrum disorders because Pica-related behaviors are mostly involuntary, recurrent, and persistent to soothe the anxiety and distress, and resistance to stop the behaviors causes increased level of anxiety and distress. This hypothesis is supported by studies that have found that Pica has the same treatment as OCD, i.e selective serotonin reuptake inhibitors.
The cause of Pica has not been identified. To review risk factors for the development of Pica, click here.
Differentiating ((Page name)) from other Diseases
Pica must be differentiated from other psychiatric diseases including autism, schizophrenia, other eating disorders, developmental delay in children, substance abuse.
Epidemiology and Demographics
- The prevalence and incidence of Pica is challenging to estimate due to several reasons such as: under-reporting the cases, cultural and social issues, different definition of Pica in studies.
- The incidence of Pica decreases with age. Studies show 20-30% of children who are between 1-6 years old have developed Pica.
- Boys are slightly more affected by Pica than girls.
- The majority of Pica cases are reported in Africa.
Common risk factors in the development of Pica include:
- Nutritional deficiency
- Child abuse, child neglect, family problem, parental separation, low socioeconomic status
- Cultural factors
- Mental disorders
- Learning and developmental disability such as autistic spectrum disorder, attention-deficit hyperactivity disorder
There is insufficient evidence to recommend routine screening for Pica.
Natural History, Complications, and Prognosis
If left untreated, patients with Pica may progress to develop:
- Iron deficiency anemia especially during pregnancy. This complication may occur due to binding of clay particle to iron or acting as an ion exchanger resin.
- Lead poisoning 
- Parasite infection (e.g. ,toxocariasis, toxoplasmosis, ascariasis, giardiasis, cysticercosis)
- Electrolyte abnormalities such as zinc deficiency, hypokalemia, hyperkalemia, hyperphosphatemia and metabolic alkalosis.
- Constipation and intestinal obstruction, bleeding and perforation.
- Social stigmatization especially in children.
- Tooth decay and sensitivity.
- High blood sugar and obesity due to amylophagia.
- Maternal Pica may lead to neurological disability and delayed motor function in newborns.
Diagnostic Study of Choice
The diagnosis of Pica is based on the criteria from Diagnosis and Statistical Manual of Mental Disorders (DSM-5), which include:
1.Person must have been eating non-nutritive nonfoods for at least one month.
2.This eating must be considered abnormal for the person's stage of development.
3.Eating these substances cannot be associated with a cultural practice that is considered normal in the social context of the individual.
4.For people who currently have a medical condition (e.g.: pregnancy) or a mental disorder (e.g.: autism spectrum disorder), the action of eating non-nutritive nonfoods should only be considered pica if it is dangerous and requires extra medical investigation or treatment on top of what they are already receiving for their pre-existing condition.
History and Symptoms
Symptoms of Pica are variable and depend on the material which is ingested.
Physicians should seek the details of the exposure, including:
- the substance type,
- the amount of substance,
- duration of exposure,
- situations where behavior usually happens,
- any co-ingestions, and
- symptoms of toxicity
Patients with Pica usually appear normal. However, sings of poisoning and complications of the ingested substance should be sought:
- Ingestion of some substances may lead to bezoar formation and consequently, intestinal obstruction, ulceration, and perforation,
- Lead poisoning symptoms include:
- cranial nerve palsy,
- cognitive impairment,
- peripheral neuropathy,
- abdominal pain and constipation,
- lead-line at the junction of gums and teeth, and
- developmental delay in children.
- Signs of parasitic infections (Toxocara and Ascaris) due to clay ingestion include:
- hepatomegaly, and
- visual disturbance.
- Malnourishment, especially in children
- Signs of iron deficiency anemia:
- easy fatigability,
- poor appetite,
- tachycardia and a soft ejection systolic flow murmur in severe cases.
- Dental complications such as severe abrasion and tooth damages.
Laboratory findings consistent with the diagnosis of Pica include:
- CBC (anemia)
- Electrolyte and nutrient evaluation (zinc deficiency, hyperkalemia)
- Liver function test
- Stool exam for parasite infections
- Blood lead concentration
There are no ECG findings associated with Pica.
There are no x-ray findings associated with Pica. However, an x-ray may be helpful in the diagnosis of complications of Pica, which include lead lines at the metaphysis of long bones and foreign bodies in chest or abdominal x-ray.
Echocardiography or Ultrasound
There are no echocardiography/ultrasound findings associated with Pica. However, an ultrasound may be helpful to reveal the location, size and the nature of the substance.
There are no CT scan findings associated with Pica.
There are no MRI findings associated with Pica.
Other Imaging Findings
There are no other imaging findings associated with Pica.
Other Diagnostic Studies
There are no other diagnostic studies associated with Pica.
The majority of cases of Pica are self-limited and require only supportive care. Supportive therapy for Pica includes:
- nutrient supplements such as iron and zinc in case of deficiency.
- Behavioral therapy, psychotherapy and family counseling particularly in children.
Surgical intervention is not recommended for the management of Pica Unless it causes severe obstruction or perforation.
Effective measures for the primary prevention of Pica include:
- Identifying high- risk populations such as pregnant women and children who live in old house with lead paint,
- Nutrition education in at-risk populations about the danger and consequences of Pica,
- Educating parents to supervise their children and make their home and environment safe.
There are no established measures for the secondary prevention of pica.
- ↑ 1.0 1.1 1.2 Parry-Jones B, Parry-Jones WL (March 1992). "Pica: symptom or eating disorder? A historical assessment". Br J Psychiatry. 160: 341–54. doi:10.1192/bjp.160.3.341. PMID 1562860.
- ↑ 2.0 2.1 2.2 Rose EA, Porcerelli JH, Neale AV (2000). "Pica: common but commonly missed". J Am Board Fam Pract. 13 (5): 353–8. PMID 11001006.
- ↑ Miao D, Young SL, Golden CD (2015). "A meta-analysis of pica and micronutrient status". Am J Hum Biol. 27 (1): 84–93. doi:10.1002/ajhb.22598. PMC 4270917. PMID 25156147.
- ↑ 4.0 4.1 Ali, Zainab (2009). "Pica in people with intellectual disability: a literature review of aetiology, epidemiology and complications". Journal of Intellectual & Developmental Disability. 26 (3): 205–215. doi:10.1080/13668250020054486. ISSN 1366-8250.
- ↑ von Garnier C, Stünitz H, Decker M, Battegay E, Zeller A (October 2008). "Pica and refractory iron deficiency anaemia: a case report". J Med Case Rep. 2: 324. doi:10.1186/1752-1947-2-324. PMC 2567333. PMID 18838005.
- ↑ 6.0 6.1 6.2 6.3 6.4 Leung A, Hon KL (2019). "Pica: A Common Condition that is Commonly Missed - An Update Review". Curr Pediatr Rev. 15 (3): 164–169. doi:10.2174/1573396315666190313163530. PMID 30868957. Vancouver style error: initials (help)
- ↑ Kettaneh A, Eclache V, Fain O, Sontag C, Uzan M, Carbillon L, Stirnemann J, Thomas M (February 2005). "Pica and food craving in patients with iron-deficiency anemia: a case-control study in France". Am J Med. 118 (2): 185–8. doi:10.1016/j.amjmed.2004.07.050. PMID 15694906.
- ↑ Young SL, Khalfan SS, Farag TH, Kavle JA, Ali SM, Hajji H, Rasmussen KM, Pelto GH, Tielsch JM, Stoltzfus RJ (July 2010). "Association of pica with anemia and gastrointestinal distress among pregnant women in Zanzibar, Tanzania". Am J Trop Med Hyg. 83 (1): 144–51. doi:10.4269/ajtmh.2010.09-0442. PMC 2912591. PMID 20595493.
- ↑ Young SL, Wilson MJ, Miller D, Hillier S (September 2008). "Toward a comprehensive approach to the collection and analysis of pica substances, with emphasis on geophagic materials". PLoS One. 3 (9): e3147. doi:10.1371/journal.pone.0003147. PMC 2522275. PMID 18773081.
- ↑ Johns T, Duquette M (February 1991). "Detoxification and mineral supplementation as functions of geophagy". Am J Clin Nutr. 53 (2): 448–56. doi:10.1093/ajcn/53.2.448. PMID 1989412.
- ↑ Dominy NJ, Davoust E, Minekus M (January 2004). "Adaptive function of soil consumption: an in vitro study modeling the human stomach and small intestine". J Exp Biol. 207 (Pt 2): 319–24. doi:10.1242/jeb.00758. PMID 14668315.
- ↑ Rangwala SD, Tobin MK, Birk DM, Butts JT, Nikas DC, Hahn YS (2017). "Pica in a Child with Anterior Cingulate Gyrus Oligodendroglioma: Case Report". Pediatr Neurosurg. 52 (4): 279–283. doi:10.1159/000477816. PMID 28704833.
- ↑ Singh, Nirbhay N.; Ellis, Cynthia R.; Crews, W. David; Singh, Yadhu N. (1994). "Does Diminished Dopaminergic Neurotransmission Increase Pica?". Journal of Child and Adolescent Psychopharmacology. 4 (2): 93–99. doi:10.1089/cap.1994.4.93. ISSN 1044-5463.
- ↑ Hergüner S, Ozyildirim I, Tanidir C (December 2008). "Is Pica an eating disorder or an obsessive-compulsive spectrum disorder?". Prog Neuropsychopharmacol Biol Psychiatry. 32 (8): 2010–1. doi:10.1016/j.pnpbp.2008.09.011. PMID 18848964.
- ↑ Stein DJ, Bouwer C, van Heerden B (December 1996). "Pica and the obsessive-compulsive spectrum disorders". S Afr Med J. 86 (12 Suppl): 1586–8, 1591–2. PMID 9180801.
- ↑ Bhatia, Manjeet S.; Gupta, Ravi (2009). "Pica responding to SSRI: An OCD spectrum disorder?". The World Journal of Biological Psychiatry. 10 (4–3): 936–938. doi:10.1080/15622970701308389. ISSN 1562-2975.
- ↑ 17.0 17.1 Rabel A, Leitman SF, Miller JL (February 2016). "Ask about ice, then consider iron". J Am Assoc Nurse Pract. 28 (2): 116–20. doi:10.1002/2327-6924.12268. PMC 4635104. PMID 25943566.
- ↑ Kar SK, Kamboj A, Kumar R (2015). "Pica and psychosis - clinical attributes and correlations: a case report". J Family Med Prim Care. 4 (1): 149–50. doi:10.4103/2249-4863.152277. PMC 4366992. PMID 25811011.
- ↑ Mills ME (June 2007). "Craving more than food: the implications of pica in pregnancy". Nurs Womens Health. 11 (3): 266–73. doi:10.1111/j.1751-486X.2007.00156.x. PMID 17883773.
- ↑ Young SL, Sherman PW, Lucks JB, Pelto GH (June 2011). "Why on earth?: Evaluating hypotheses about the physiological functions of human geophagy". Q Rev Biol. 86 (2): 97–120. doi:10.1086/659884. PMID 21800636.
- ↑ Khan Y, Tisman G (March 2010). "Pica in iron deficiency: a case series". J Med Case Rep. 4: 86. doi:10.1186/1752-1947-4-86. PMC 2850349. PMID 20226051.
- ↑ 22.0 22.1 Moore DJ (May 2017). "Sapophagia: A Case of Irish Spring Soap Pica". J Emerg Nurs. 43 (3): 281–283. doi:10.1016/j.jen.2017.03.009. PMID 28476302.
- ↑ Hartmann AS, Poulain T, Vogel M, Hiemisch A, Kiess W, Hilbert A (November 2018). "Prevalence of pica and rumination behaviors in German children aged 7-14 and their associations with feeding, eating, and general psychopathology: a population-based study". Eur Child Adolesc Psychiatry. 27 (11): 1499–1508. doi:10.1007/s00787-018-1153-9. PMID 29675593.
- ↑ Fawcett EJ, Fawcett JM, Mazmanian D (June 2016). "A meta-analysis of the worldwide prevalence of pica during pregnancy and the postpartum period". Int J Gynaecol Obstet. 133 (3): 277–83. doi:10.1016/j.ijgo.2015.10.012. PMID 26892693.
- ↑ 25.0 25.1 Tokue H, Takahashi Y, Hirasawa S, Awata S, Kobayashi S, Shimada T, Tokue A, Sano R, Kominato Y, Tsushima Y (2015). "Intestinal obstruction in a mentally retarded patient due to pica". Ann Gen Psychiatry. 14: 22. doi:10.1186/s12991-015-0060-4. PMC 4521501. PMID 26236386.
- ↑ 26.0 26.1 Matson JL, Hattier MA, Belva B, Matson ML (September 2013). "Pica in persons with developmental disabilities: approaches to treatment". Res Dev Disabil. 34 (9): 2564–71. doi:10.1016/j.ridd.2013.05.018. PMID 23747942.
- ↑ Mischoulon D, Eddy KT, Keshaviah A, Dinescu D, Ross SL, Kass AE, Franko DL, Herzog DB (May 2011). "Depression and eating disorders: treatment and course". J Affect Disord. 130 (3): 470–7. doi:10.1016/j.jad.2010.10.043. PMC 3085695. PMID 21109307.
- ↑ Kendall-Tackett K (June 2002). "The health effects of childhood abuse: four pathways by which abuse can influence health". Child Abuse Negl. 26 (6–7): 715–29. doi:10.1016/s0145-2134(02)00343-5. PMID 12201164.
- ↑ 29.0 29.1 29.2 Al Nasser Y, Muco E, Alsaad AJ. PMID 30335275. Missing or empty
- ↑ Tucker MH, Holmes J, Harley S, Garcia MR, Custodio H (September 2017). "Case 1: Fever and Ataxia in a Toddler with Pica". Pediatr Rev. 38 (9): 435–436. doi:10.1542/pir.2016-0189. PMID 28864734.
- ↑ Setime MA, Sesay S, Cainelli F, Vento S (September 2013). "A case of severe hypokalemic myopathy due to clay ingestion". Isr Med Assoc J. 15 (9): 524–5. PMID 24340849.
- ↑ Kalgaonkar SR, Ramakantan R (2018). "Pica and the radiologist - beyond the radiology report … digging deeper". Indian J Radiol Imaging. 28 (3): 330–332. doi:10.4103/ijri.IJRI_48_18. PMC 6176668. PMID 30319211.
- ↑ 33.0 33.1 33.2 McNaughten B, Bourke T, Thompson A (October 2017). "Fifteen-minute consultation: the child with pica". Arch Dis Child Educ Pract Ed. 102 (5): 226–229. doi:10.1136/archdischild-2016-312121. PMID 28487433.
- ↑ Johnson CD, Koh SH, Shynett B, Koh J, Johnson C (2006). "An uncommon dental presentation during pregnancy resulting from multiple eating disorders: pica and bulimia: case report". Gen Dent. 54 (3): 198–200. PMID 16776414.
- ↑ Edwards CH, Johnson AA, Knight EM, Oyemade UJ, Cole OJ, Westney OE, Jones S, Laryea H, Westney LS (June 1994). "Pica in an urban environment". J Nutr. 124 (6 Suppl): 954S–962S. doi:10.1093/jn/124.suppl_6.954S. PMID 8201446.
- ↑ Mycyk MB, Leikin JB (May 2004). "Combined exchange transfusion and chelation therapy for neonatal lead poisoning". Ann Pharmacother. 38 (5): 821–4. doi:10.1345/aph.1D475. PMID 15026564.
- ↑ Mireku MO, Davidson LL, Zoumenou R, Massougbodji A, Cot M, Bodeau-Livinec F (August 2018). "Consequences of prenatal geophagy for maternal prenatal health, risk of childhood geophagy and child psychomotor development". Trop Med Int Health. 23 (8): 841–849. doi:10.1111/tmi.13088. PMC 6103800. PMID 29876999.
- ↑ Hartmann, Andrea S.; Becker, Anne E.; Hampton, Claire; Bryant-Waugh, Rachel (2012). "Pica and Rumination Disorder inDSM-5". Psychiatric Annals. 42 (11): 426–430. doi:10.3928/00485713-20121105-09. ISSN 0048-5713.
- ↑ "Screening for elevated blood lead levels. American Academy of Pediatrics Committee on Environmental Health". Pediatrics. 101 (6): 1072–8. June 1998. PMID 9614424.
- ↑ Woodhall DM, Garcia AP, Shapiro CA, Wray SL, Shane AL, Mani CS, Stimpert KK, Fox LM, Montgomery SP (October 2017). "Assessment of U.S. Pediatrician Knowledge of Toxocariasis". Am J Trop Med Hyg. 97 (4): 1243–1246. doi:10.4269/ajtmh.17-0232. PMC 5637614. PMID 28820703.
- ↑ Dold C, Holland CV (July 2011). "Ascaris and ascariasis". Microbes Infect. 13 (7): 632–7. doi:10.1016/j.micinf.2010.09.012. PMID 20934531.
- ↑ Hon KL, Fung CK, Leung AK (December 2017). "Childhood lead poisoning: an overview". Hong Kong Med J. 23 (6): 616–21. doi:10.12809/hkmj176214. PMID 29026055.
- ↑ Chatzimavroudis G, Christopoulos P, Atmatzidis S, Papadakis G, Nalbanti P, Papaziogas B, Koutelidakis I, Atmatzidis K (July 2011). "Pica: an uncommon cause of acute abdominal pain in children". Indian J Pediatr. 78 (7): 886–7. doi:10.1007/s12098-011-0376-2. PMID 21328077.
- ↑ Sabouraud S, Testud F, Descotes J, Benevent M, Soglu G (March 2008). "Lead poisoning following ingestion of pieces of lead roofing plates: pica-like behavior in an adult". Clin Toxicol (Phila). 46 (3): 267–9. doi:10.1080/15563650701639014. PMID 17906991.
- ↑ Johnson CD, Shynett B, Dosch R, Paulson R (2007). "An unusual case of tooth loss, abrasion, and erosion associated with a culturally accepted habit". Gen Dent. 55 (5): 445–8. PMID 17899724.
- ↑ Woywodt A, Kiss A (March 2002). "Geophagia: the history of earth-eating". J R Soc Med. 95 (3): 143–6. doi:10.1258/jrsm.95.3.143. PMC 1279487. PMID 11872770.
- ↑ Griffith JP, Bhanot VK (March 1994). "Geophagia in a chronic hemodialysis patient". W V Med J. 90 (3): 106–7. PMID 8197741.
- ↑ Waller BR, Pendergrass LB (November 1995). "Index of suspicion. Case 3. Strangulated hernia of the small intestine". Pediatr Rev. 16 (11): 433, 435–6. PMID 8539196.
- ↑ Roy A, Fuentes-Afflick E, Fernald L, Young SL (January 2018). "Pica is prevalent and strongly associated with iron deficiency among Hispanic pregnant women living in the United States". Appetite. 120: 163–170. doi:10.1016/j.appet.2017.08.033. PMID 28864256. Vancouver style error: initials (help)
- ↑ Sadeghzadeh M, Khoshnevisasl P, Sadeghzadeh S (August 2017). "The relation between pica and iron deficiency in children in Zanjan, Islamic Republic of Iran: a case-control study". East Mediterr Health J. 23 (6): 404–407. doi:10.26719/2017.23.6.404. PMID 28836652.
- ↑ Kelkitli E, Ozturk N, Aslan NA, Kilic-Baygutalp N, Bayraktutan Z, Kurt N, Bakan N, Bakan E (April 2016). "Serum zinc levels in patients with iron deficiency anemia and its association with symptoms of iron deficiency anemia". Ann Hematol. 95 (5): 751–6. doi:10.1007/s00277-016-2628-8. PMID 26931116.
- ↑ Mishori R, McHale C (July 2014). "Pica: an age-old eating disorder that's often missed". J Fam Pract. 63 (7): E1–4. PMID 25198212.
- ↑ Roberts JW, Dickey P (1995). "Exposure of children to pollutants in house dust and indoor air". Rev Environ Contam Toxicol. 143: 59–78. doi:10.1007/978-1-4612-2542-3_3. PMID 7501867.
- ↑ Hauptman M, Bruccoleri R, Woolf AD (September 2017). "An Update on Childhood Lead Poisoning". Clin Pediatr Emerg Med. 18 (3): 181–192. doi:10.1016/j.cpem.2017.07.010. PMC 5645046. PMID 29056870.
- ↑ Ezzeddin N, Zavoshy R, Noroozi M, Jahanihashemi H, Riseh SH (December 2015). "Prevalence and risk factors for pica during pregnancy in Tehran, Iran". Eat Weight Disord. 20 (4): 457–63. doi:10.1007/s40519-015-0198-8. PMID 26143570.
- ↑ Williams, Don E.; Kirkpatrick-Sanchez, Sharon; Enzinna, Christie; Dunn, Jacqueline; Borden-Karasack, Deborah (2009). "The Clinical Management and Prevention of Pica: A Retrospective Follow-Up of 41 Individuals with Intellectual Disabilities and Pica". Journal of Applied Research in Intellectual Disabilities. 22 (2): 210–215. doi:10.1111/j.1468-3148.2008.00490.x. ISSN 1360-2322.
- ↑ Young, Sera L.; Rasmussen, Kathleen M.; Kavle, Justine A.; Farag, Tamer H.; Hajji, Hamad; Khalfan, Sabra S.; Pelto, Gretel H.; Stoltzfus, Rebecca J.; Ali, Said M.; Tielsch, James M. (2010). "Association of Pica with Anemia and Gastrointestinal Distress among Pregnant Women in Zanzibar, Tanzania". The American Journal of Tropical Medicine and Hygiene. 83 (1): 144–151. doi:10.4269/ajtmh.2010.09-0442. ISSN 0002-9637.