Rh Iso-immunization

*(Follow up of ICT +ve patient* ) 

Mrs Rekha (Name changed), 33 years, B-ve blood group with Husband  being O+ve, second gravida with previous one live issue and had received *Anti-D antenatally and postnataly in previous pregnancy,* Now referred to _PROMISE ULTRASOUND AND FETAL MEDICINE CENTER_ at *15 weeks with ICT positive* ( only qualitative done  at previous center).

Lets discuss the management

*Step One* :  

*Ask for quantitative ICT (i.e. Titre values)*

Patients titre was 1:8.

Remember A critical titre is defined as antibody levels which pose a significant risk of fetal anemia or Hydrops. For RHD antigen critical titre is 1:16 or 1:32 depending on the laboratory threshold. Significant risk of fetal anaemia or hydrops is present once critical titres are reached or there is sudden rise in antibody level. A previous Injection of Anti-D may present as ICT positive in present pregnancy especially if interpregnancy interval is less than three years however the titres would be low (1:4 or Even not detected)

 *Step Two:* 

*Monitor quantitative ICT (i.e. Titre values) every month till 28 weeks and every 15 days till delivery to see if titres remain below critical titres.* In any event of potential feto-maternal hemorrhage (Like Bleeding in previa or abruption or abdomen blow) it should be repeated after every episode. *Unfortunately, after two months, at 26 weeks, our patient, without any above said event, developed titres 1:32 (checked twice by laboratory).*[/vc_column_text]

*Step three* : Since this patient has reached critical titres, *a weekly Ultrasound monitoring for for potential development of fetal anemia is recommended.* It is monitored though *Peak systolic velocity (PSV) of Middle cereblar artery ( MCA)* which is to be kept *below 1.5 MOMs* for gestation  and  other *signs of Fetal anemia* _(like pericardial effusion, Tricuspid regurgitation, Placentomegaly, Polyhydraminos, scalp edema, skin edema, Ascites and finally fetal hydrops)_ are also to be looked upon. In other patients, where the critical titres are not reached, as discussed monthly titre monitoring with routine Ultrasonography is advised.

Our patient was monitored by MCA PSV and other USG signs of fetal anemia, delivered at 37 weeks with a healthy 2.8 kg female baby who required 7 days of NICU Admission for Mild neonatal jaundice with no requirement for exchange transfusion.

 *In Continuation:*

Had the MCA PSV increased to more than 1.5 MOM for gestation, indicating severe fetal anaemia, An Intrauterine Blood Transfusion would have been needed. Where ultrasound guided percutaneous umbilical blood sampling is performed to know the fetal haemoglobin and hematocrit followed by blood transfusion.We proudly announce that services of Intrauterine Blood Transfusion and sampling is available at *PROMISE ULTRASOUND AND FETAL MEDICINE CENTRE*

 An Important message 

*Overindulging in NIPT (Cell free DNA) after an Increased NT in first trimester can invite a future trouble*

Let’s understand the concept with a recent case of Increased NT sent to _PROMISE ULTRASOUND AND FETAL MEDICINE CENTRE_ (follow the link below for committee opinion of ACOG about the same)

A Clinical and Genetical low risk primi of 29 years was referred to our centre for a Level II scan at 19+3 weeks. At First trimester, she was found to have an *increased NT (At other centre) with normal Dual markers (PAPP-A & B-HCG* ). She was advised *NIPT by her doctor which showed LOW RISK for Trisomy 21, 18 & 13).* While doing Detailed anatomical surveillance Ultrasound (Level II), *we detected TGA ( Transposition of great arteries* ) .

Now what to do?? Remember she is 19+3 weeks.

 *Concept number one* : 

*In every case of Increased NT, Think beyond Down syndrome (or Edward or Patau* ). NIPT only caters *five* chromosomes *(21, 18, and 13, X, Y).* It doesn’t deal with rest and also *cannot* assess the risk for *fetal anomalies like ventral wall defects and neural tube defects*

An *increased NT* can also be seen in _cardiac defects, diaphragmatic hernia, exomphalos, body stalk anomaly, skeletal defects, and certain genetic syndromes, such as congenital adrenal hyperplasia, fetal akinesia, deformation sequence, Noonan syndrome, Smith-lemli-Opitz syndrome and spinal muscular atrophy._

 *Concept number two* : 

As at PROMISE ULTRASOUND AND FETAL MEDICINE CENTRE, We offer genetic counselling and detailed ultrasound evaluation at 15 to 16 weeks so that above stated anomalies can be ruled out and confident decision about *Amniocentesis (with full karyotype and Micro-Array) versus NIPT (Only Five Chromosomes* ) can be made as still we have four weeks in hand for any termination if required. *In both the cases, however a further detailed ultrasound at 19 weeks and a fetal echocardiography is recommended too* .

We must proudly emphasise here that while doing NT Scan, We always look for above stated problems that potentially could lead to Increased NT.

So in conclusion NIPT is part of the puzzle, but it is not the whole picture. A comprehensive approach that combines NIPT with a series of ultrasounds and other screening tests based on the patient’s risk factors can provide the optimal combination of effective prenatal care and patient peace of mind.


 *Case Discussion* :


*PPROM* at *19 weeks* and role of *Ultrasound guided Amnio Infusion* and *Fibrin Sealants*

This Patient, Conceived with IVF, Had a leak at 19 weeks with *Absolute Anhydraminos on Ultrasound,* However She was  free from any clinical signs of overt chorioamnionitis like infection, fever, increased C reactive protein (CRP), white blood cells and uterine tenderness. Detailed informed counseling regarding the potential *risks (chronic oligohydramnios, potter facies, club feet and pulmonary hypoplasia with universal moderate pulmonary artery hypertension)* and benefits of continuing pregnancy and about the procedure was done.

Under Strict Aseptic Precautions, *Ultrasound Guided Amnioinfusion* was done with 20 guage spinal needle, slowly avoiding any contact with fetus or cord and  Normal saline was transfused  till vertical pocket increased to 5 cm. Patient was made to rest and discharged . *If the leaking persisits, Patient is advised to come back for Cryoprecipitate infusion.*