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Conjoined twins

MedGen UID:
52901
•Concept ID:
C0041428
•
Congenital Abnormality
Synonyms: Conjoined Twin; Conjoined Twins; Siamese Twin; Siamese Twins; Twin, Conjoined; Twin, Siamese; Twins, Conjoined; Twins, Siamese
SNOMED CT: Conjoined twins (41337007); Siamese twins (41337007)
 
Monarch Initiative: MONDO:0958083

Definition

A monoamniotic twin gestation in which the twins share one or more organs. [from NCI]

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVConjoined twins

Professional guidelines

PubMed

Screening, Management and Delivery in Twin Pregnancy.
von Kaisenberg C, Klaritsch P, Ochsenbein-Kölble N, Hodel ME, Nothacker M, Hecher K
Ultraschall Med 2021 Aug;42(4):367-378. Epub 2020 Oct 5 doi: 10.1055/a-1248-8896. PMID: 33017845
Prenatal diagnosis and obstetric management.
O'Brien P, Nugent M, Khalil A
Semin Pediatr Surg 2015 Oct;24(5):203-6. Epub 2015 Jun 23 doi: 10.1053/j.sempedsurg.2015.06.002. PMID: 26382256
History of treatment of conjoined twins.
Kobylarz K
Anaesthesiol Intensive Ther 2014 Apr-Jun;46(2):116-23. doi: 10.5603/AIT.2014.0022. PMID: 24858972

Recent clinical studies

Etiology

Monochorionic monoamniotic twin pregnancies.
Khairudin D, Khalil A
Best Pract Res Clin Obstet Gynaecol 2022 Nov;84:96-103. Epub 2022 Aug 24 doi: 10.1016/j.bpobgyn.2022.08.004. PMID: 36123247
Conjoined Twin Separation: Review of 30-Year Case Experience and Lessons Learned.
Shafarenko MS, Zuker RM
Plast Reconstr Surg 2022 Jul 1;150(1):133-144. Epub 2022 May 17 doi: 10.1097/PRS.0000000000009267. PMID: 35575643
Separation of Craniopagus Twins.
Johnson R, Weir P
Camb Q Healthc Ethics 2016 Jan;25(1):38-49. doi: 10.1017/S0963180115000274. PMID: 26788945
Human laterality disorders.
Peeters H, Devriendt K
Eur J Med Genet 2006 Sep-Oct;49(5):349-62. Epub 2006 Jan 3 doi: 10.1016/j.ejmg.2005.12.003. PMID: 16461029
Ethics and conjoined twins.
Atkinson L
Childs Nerv Syst 2004 Aug;20(8-9):504-7. Epub 2004 Jul 17 doi: 10.1007/s00381-004-0983-6. PMID: 15258819

Diagnosis

Thoracopagus conjoined twins.
Ostatníková Michaela, Chválna Zuzana, Gábor Martin, Záhumenský Jozef
Ceska Gynekol 2023;88(3):186-189. doi: 10.48095/cccg2023186. PMID: 37344184
Monochorionic monoamniotic twin pregnancies.
Khairudin D, Khalil A
Best Pract Res Clin Obstet Gynaecol 2022 Nov;84:96-103. Epub 2022 Aug 24 doi: 10.1016/j.bpobgyn.2022.08.004. PMID: 36123247
Conjoined twins and conjoined triplets: At the heart of the matter.
Oostra RJ, Schepens-Franke AN, Magno G, Zanatta A, Boer LL
Birth Defects Res 2022 Jul 15;114(12):596-610. Epub 2022 Jun 29 doi: 10.1002/bdr2.2066. PMID: 35766259Free PMC Article
Conjoined Twins.
Kattel P
JNMA J Nepal Med Assoc 2018 Mar-Apr;56(211):708-710. PMID: 30381771Free PMC Article
Intracranial fetus-in-fetu with numerous fully developed organs.
Traisrisilp K, Srisupundit K, Suwansirikul S, Norasetthada T, Kosarat S, Tongsong T
J Clin Ultrasound 2018 Sep;46(7):487-493. Epub 2017 Nov 28 doi: 10.1002/jcu.22566. PMID: 29193240

Therapy

Xenopus, an ideal model organism to study laterality in conjoined twins.
Tisler M, Schweickert A, Blum M
Genesis 2017 Jan;55(1-2) doi: 10.1002/dvg.22993. PMID: 28132423
Cardiothoracic surgery.
Tsang VT, Tran PK, de Leval M
Semin Pediatr Surg 2015 Oct;24(5):252-3. Epub 2015 Jul 4 doi: 10.1053/j.sempedsurg.2015.07.005. PMID: 26382267
The separation procedure.
Kiely EM, Spitz L
Semin Pediatr Surg 2015 Oct;24(5):231-6. Epub 2015 Jun 26 doi: 10.1053/j.sempedsurg.2015.06.007. PMID: 26382263
The management of conjoined twins: Cardiology assessment.
Andrews RE, Yates RW, Sullivan ID
Semin Pediatr Surg 2015 Oct;24(5):217-20. Epub 2015 Jul 9 doi: 10.1053/j.sempedsurg.2015.07.003. PMID: 26382259
Anaesthesia of conjoined twins.
Kobylarz K
Anaesthesiol Intensive Ther 2014 Apr-Jun;46(2):124-9. doi: 10.5603/AIT.2014.0023. PMID: 24858973

Prognosis

Conjoined thoracopagus twins: A systematic review of the anomalies and outcome of surgical separation.
Saxena R, Sinha A, Pathak M, Rathod KJ
Afr J Paediatr Surg 2023 Jul-Sep;20(3):157-165. doi: 10.4103/ajps.ajps_77_22. PMID: 37470549Free PMC Article
Thoracopagus conjoined twins.
Ostatníková Michaela, Chválna Zuzana, Gábor Martin, Záhumenský Jozef
Ceska Gynekol 2023;88(3):186-189. doi: 10.48095/cccg2023186. PMID: 37344184
Conjoined twins: Pre-birth management, changes to NRP, and transport.
C Sager E, Thomas A, C Sundgren N
Semin Perinatol 2018 Oct;42(6):321-328. Epub 2018 Jul 30 doi: 10.1053/j.semperi.2018.07.008. PMID: 30150080
Intracranial fetus-in-fetu with numerous fully developed organs.
Traisrisilp K, Srisupundit K, Suwansirikul S, Norasetthada T, Kosarat S, Tongsong T
J Clin Ultrasound 2018 Sep;46(7):487-493. Epub 2017 Nov 28 doi: 10.1002/jcu.22566. PMID: 29193240
Conjoined twins.
Spitz L
Prenat Diagn 2005 Sep;25(9):814-9. doi: 10.1002/pd.1268. PMID: 16170846

Clinical prediction guides

Monochorionic monoamniotic twin pregnancies.
Khairudin D, Khalil A
Best Pract Res Clin Obstet Gynaecol 2022 Nov;84:96-103. Epub 2022 Aug 24 doi: 10.1016/j.bpobgyn.2022.08.004. PMID: 36123247
Cross-cultural representations of conjoined twins.
Tekendo-Ngongang C, Williams KJ, Williams MS
Am J Med Genet C Semin Med Genet 2021 Jun;187(2):240-253. Epub 2021 May 13 doi: 10.1002/ajmg.c.31897. PMID: 33982866
Conjoined Twins.
Kattel P
JNMA J Nepal Med Assoc 2018 Mar-Apr;56(211):708-710. PMID: 30381771Free PMC Article
Peri-operative intensive care.
Walsh SA, Peters MJ
Semin Pediatr Surg 2015 Oct;24(5):254-9. Epub 2015 Jul 30 doi: 10.1053/j.sempedsurg.2015.07.006. PMID: 26382268
Epidemiological and clinical analysis of a consecutive series of conjoined twins in Spain.
Martínez-Frías ML, Bermejo E, Mendioroz J, Rodríguez-Pinilla E, Blanco M, Egüés J, Félix V, García A, Huertas H, Nieto C, López JA, López S, Paisán L, Rosa A, Vázquez MS
J Pediatr Surg 2009 Apr;44(4):811-20. doi: 10.1016/j.jpedsurg.2008.07.002. PMID: 19361646

Recent systematic reviews

Conjoined thoracopagus twins: A systematic review of the anomalies and outcome of surgical separation.
Saxena R, Sinha A, Pathak M, Rathod KJ
Afr J Paediatr Surg 2023 Jul-Sep;20(3):157-165. doi: 10.4103/ajps.ajps_77_22. PMID: 37470549Free PMC Article
Heteropagus twins: six cases with systematic review and embryological insights.
Mathur P, Sharma S, Mittal P, Yadav RK, Barolia D
Pediatr Surg Int 2022 Jul;38(7):963-983. Epub 2022 May 14 doi: 10.1007/s00383-022-05135-w. PMID: 35567628
The Outcomes of Surgical Separation in Thoracopagus Twins with Conjoined Hearts: An Analysis of the Literature.
Collins RT 2nd, O'Connor MJ
Pediatr Cardiol 2021 Apr;42(4):875-882. Epub 2021 Apr 15 doi: 10.1007/s00246-021-02555-8. PMID: 33856497
Diprosopus: Systematic review and report of two cases.
Bidondo MP, Groisman B, Tardivo A, Tomasoni F, Tejeiro V, Camacho I, Vilas M, Liascovich R, Barbero P
Birth Defects Res A Clin Mol Teratol 2016 Dec;106(12):993-1007. Epub 2016 Oct 5 doi: 10.1002/bdra.23549. PMID: 27704687
Impact of cord entanglement on perinatal outcome of monoamniotic twins: a systematic review of the literature.
Rossi AC, Prefumo F
Ultrasound Obstet Gynecol 2013 Feb;41(2):131-5. doi: 10.1002/uog.12345. PMID: 23371346

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