Twin-to-Twin Transfusion Syndrome

 

Ms. Sarika Yadav

Assistant Professor, Department Child Health Nursing, SGT University, Gurgaon, Haryana, India

*Corresponding Author Email: sarika@sgtuniversity.org

 

ABSTRACT:

Twin-Twin transfusion syndrome (TTTS) leads to high rates of perinatal morbidity and mortality due to its poorly understood etiology and difficulty in diagnosis and treatment. Early diagnosis during foetal ultrasound is, therefore important in reducing the morbidity and mortality rates. TTTS is a phenomenon almost exclusive to monochorionic twin pregnancies. TTTS is associated with high rates of perinatal mortality. The donor twin is characterized by oliguria, oligohydram-nios or anhydramnios, growth restriction and abnormal umbilical artery by Doppler velocimetry. The recipient, on the other hand, is characterized by polyuria polyhydramnios abnormal venous dopplers cardiac enlargement /failure, and eventually hydrops. The present study reported a case of TTTS an unusual presentation.

 

KEYWORDS: Monochorionic twin, Twin Discordance, Stuck twin, oligohydram-nios, anhydramnios.

 

 


INTRODUCTION:

Twin to Twin Transfusion Syndrome, or TTTS, is a disease of the placenta. This condition affects twins or other multiples that share a single placenta containing blood vessels going from one baby to the other.

 

Blood from the smaller "donor" twin is transferred to the larger "recipient" twin through interconnecting vessels causing an unequal exchange of blood.

 

The recipient twin is at risk for heart failure receiving too much blood from both the placenta and donor twin, forcing its heart to work harder, while the donor twin is at risk for loss of blood.1

 

 

Twin-to-twin transfusion syndrome (TTTS), also known as Feto-Fetal Transfusion Syndrome (FFTS) and Twin Oligohydramnios-Polyhydramnios Sequence (TOPS) is a complication of disproportionate blood supply, resulting in high morbidity and mortality. It can affect monochorionic multiples, that is, multiple pregnancies where two or more fetuses share achorion and hence a single placenta. Severe TTTS has a 60–100% mortality rate.2

 

Definition:

Twin to Twin Transfusion Syndrome (TTTS) is a prenatal condition in which twins share unequal amounts of the placenta’s blood supply resulting in the two fetuses growing at different rates. The donor twin is often anemic and the recipient twin is often plethoric with hemoglobin differences greater than 5 g/dl.

 

Pathology:

TTTS results from an unbalanced arterio-venous (AV) communication in the placenta with increasing evidence implicating asymmetric anastomotic patterns in its aetiology. The smaller twin with oligohydramnious which also called "stuck twin" that pumps away blood is termed the donor twin while the larger twin receiving extra blood is termed the recipient twin.3

 

INCIDENCE:

·        TTTS occurs about 15 % of the time among identical twins which are always the same sex.

·        The prevalence of this condition is approximately 1 to 3 per 10,000 birth.4

 

TYPES

1.    Chronic TTTS:

Describes those cases that appear early in pregnancy (12-26 weeks’ gestation). These cases are the most serious because the babies are immature and cannot be delivered. In addition, the twins will have a longer time during their development in the womb to be affected by the TTTS abnormalities. Without treatment, most of these babies would not survive and of the survivors, most would have handicaps or birth defects.

 

2. Acute TTTS:

describes those cases that occur suddenly, whenever there is a major difference in the blood pressures between the twins. This may occur in labor at term, or during the last third of pregnancy whenever one twin becomes gravely ill or even passes away as a result of the abnormalities in their shared placenta. Acute TTTS twins may have a better chance to survive based on their gestational age, but may have a greater chance of surviving with handicaps.5

 

Stages:

A staging system proposed by fetal surgeon Dr. Ruben Quintero is commonly used to classify the severity of TTTS.

 

Stage I:

A small amount of amniotic fluid (oligohydramnios) is found around the donor twin and a large amount of amniotic fluid (polyhydramnios) is found around the recipient twin.

 

Stage II:

In addition to the description above, the ultrasound is not able to identify the bladder in the donor twin.

 

Stage III: In addition to the characteristics of Stages I and II, there is abnormal blood flow in the umbilical cords of the twins.

 

Stage IV:

In addition to all of the above findings, the recipient twin has swelling under the skin and appears to be experiencing heart failure (fetal hydrops).

 

Stage V:

In addition to all of the above findings, one of the twins has died. This can happen to either twin. The risk to either the donor or the recipient is roughly equal amd is quite high in Stage II or higher TTTS.5

 

Signs of Twin to Twin Transfusion Syndrome in mother:

A mother whose twins have TTTS may experience:

·      Sensation of rapid growth of the womb

·      A uterus that measures large for dates

·      Abdominal pain, tightness, or contractions

·      Sudden increase in body weight

·      Swelling in the hands and legs in early pregnancy

 

Radiographic features:

Antenatal ultrasound:

General features that may suggest towards the diagnosis include:

·        Twin Growth Discordance between the two twins (>20%)

·        there may be folding of the inter-twin membrane as an early sign due to disparity in amniotic fluid volumes (amniotic fluid discordance)

·        in early pregnancy, there may be a difference in nuchal translucency between the twins

·        significant difference in umbilical cord diameter Features that may noted individually in each twin include:

 

Recipient twin is larger in size and will have an increased estimated fetal weight (EFW)

·        polyhydramnios

·        large urinary bladder

·        evidence of fetal polycythaemia

·        fetal hydrops

·        fetal cardiomegaly

·        in certain cases fetal echocardiography may also show AV valve incompetence

 

Donor twin (pump twin / stuck twin)

·        The small twin (with decreased EFW) can appear "pinned" to side of gestational sac.

·        Evidence of fetal anaemia

·        oligohydramnios

·        Small/absent urinary bladder

 

Possible predictors in first trimester ultrasound:

·        Presence of monochorionicity

·        Increased nuchal translucency and/or disparity in nuchal translucency between the twins

·        Poor crown-rump length growth of one fetus

·        Membrane folding at 10-13 weeks of gestation

·        Velamantous cord insertion6

 
Doppler:

·        Absent or reversed diastolic flow in the umbilical artery is an indication of worsening twin-to-twin transfusion syndrome

·        Abnormal Ductus Venosus Waveform pattern suggests possibility of cardiac diastolic    dysfunction 7

Treatment:

Various treatments for TTTS include:

Adjustment of amniotic fluid:

Serial Amniocentesi:

This procedure involves removal of amniotic fluid periodically throughout the pregnancy under the assumption that the extra fluid in the recipient twin can cause preterm labor, perinatal mortality, or tissue damage. In the case that the fluid does not reaccumulate, the reduction of amniotic fluid stabilizes the pregnancy. Otherwise the treatment is repeated as necessary. h time. There is a danger that if too much fluid is removed, the recipient twin could die. This procedure is associated with a 66% survival rate of at least one fetus, with a 15% risk of cerebral palsy and average delivery occurring at 29 weeks gestation.8

 

Septostomy, or Iatrogenic Disruption of the Dividing Membrane:

This procedure involves the tearing of the dividing membrane between fetuses such that the amniotic fluid of both twins mixes under the assumption that pressure is different in either amniotic sac and that its equilibration will ameliorate progression of the disease.. In addition, tearing the dividing membrane has contributed to cord entanglement and demise of fetuses through physical complications.8

 

Adjustment of blood supply:

Laser Therapy:

This procedure involves endoscopic surgery using laser to interrupt the vessels that allow exchange of blood between fetuses under the assumption that the unequal sharing of blood through these vascular communications leads to unequal levels of amniotic fluid. Each fetus remains connected to its primary source of blood and nutrition, the placenta, through the umbilical cord. This procedure is conducted once, with the exception of all vessels not having been found. The use of endoscopic instruments allows for short recovery time.

 

Twin anemia-polycythemia sequence (TAPS) may occur after laser surgery for TTTS (post-laser form). The spontaneous form of TAPS complicates approximately 3 to 5% of monochorionic twin pregnancies, whereas the post-laser form occurs in 2 to 13% of TTTS cases.

 

A recent review found that laser coagulation resulted in fewer fetal and perinatal deaths than amnioreduction and septostomy, and recommended its use for all states of TTTS.

 

Umbilical Cord Occlusio:

This procedure involves the ligation or otherwise occlusion of the umbilical cord to interrupt the exchange of blood between the fetuses. The procedure is typically offered in cases where one of the fetuses is presumed moribund and endangering the life or health of the other twin through resultant hypotension. 9

 

Prognosis for Twin-Twin Transfusion Syndrome:

Without treatment, this condition can be fatal for both twins. Fetal surgery is sometimes necessary to save one or both babies. The prognosis is usually better when the condition develops after 20 weeks’ gestation. 

 

Receiving a diagnosis of twin-twin transfusion syndrome is an emotional experience, and in some cases decisions about treatment must be made quickly. At the Cincinnati Fetal Center, we are here to help, providing a thorough, compassionate approach to each patient’s care.  10

 

CONCLUSION:

High degree of suspicion of TTTS should be there  while performing sonography of Monochorionic twins.  Timely diagnosis of twin-twin transfusion syndrome  by ultrasound is crucial to initiate the treatment early.  Delay in diagnosis may result in a delay in treatment and increased perinatal mortality and morbidity.

 

The neonatal survival of TTTS is improved by fetoscopic laser coagulation, preferely by using Solomon tecnhique. The use of active management of stage I is currently on research.

 

REFERENCES:

1.     Bhat R. Twin to twin transfusion syndrome. Kath-mandu University Medical Journal 2010; 8(1): 29: 87-90.

2.     SRinivaS PRaSad RH, Bv BalaKRiSHna .et.al. Twin to Twin Transfusion Syndrome (TTTS): An Interesting Entity in Twin Pregnancy, Indian Journal of Neonatal Medicine and Research. 2015 Apr, Vol-3(2): 7-9.

3.     Berengere Beauquier-Maccotta, Gihad E. Chalouhi .et.al, Impact of Monochorionicity and Twin to Twin Transfusion Syndrome on Prenatal Attachment, Post Traumatic Stress Disorder, Anxiety and Depressive Symptoms. https://doi.org/10.1371/journal.pone.0145649

4.      Blickstein I. The twin-twin transfusion syndrome. Obstet Gynecol. 1990;76:714–722. [PubMed].

5.     Muratore CS1, Carr SR.et.al. twin-to-twin transfusion syndrome, Journal journal of Pediatric Surgery. 2009 Jan;44(1):66-70

6.     Middeldorp JM, Sueters M, Lopriore E, Klumper FJ, Oepkes D, et al. (2007) Fetoscopic laser surgery in 100 pregnancies with severe twin-to-twin transfusion syndrome in the Netherlands. Fetal Diagn Ther 22: 190-194.

7.     Huber A, Diehl W, Bregenzer T, Hackeloer BJ, Hecher K (2006) Stage-related outcome in twin-twin transfusion syndrome treated by fetoscopic laser coagulation. Obstet Gynecol 108: 333-337.

8.     Chmait RH, Kontopoulos EV, Korst LM, Llanes A, Petisco I, et al. (2011) Stage-based outcomes of 682 consecutive cases of twin-twin transfusion syndrome treated with laser surgery: the USFetus experience. American  Journal of Obstetric and  Gynecology  204: 393 e1-e6.

9.     Kliegman M.robert, Textbook of paediatrics. Elsevier publications.:2016; edition 20. V(2).p821.

10.   Macdonal sue. Mayes’ Textbook of Midwifery. Elsevier publications:1997: 14th edition. p819-821

 

 

 

 

 

Received on 21.05.2017       Modified on 29.08.2017

Accepted on 25.11.2017      ©A&V Publications All right reserved

Asian J. Nursing Education and Research. 2018; 8(2): 295-297.

DOI: 10.5958/2349-2996.2018.00057.5