Wednesday, April 19, 2017

Apt Test in Newborn: Maternal vs Neonatal Blood

We had few cases of suspected GI bleeding, admitted or referred to our NICU. One was case of Hematochezia and other was case of fresh blood in vomitus. Both babies were born to mother with Antepartum hemorrhage. The general condition of the babies were fine, and the vitals. There was no other reason for GI bleed at such early period in these neonates.

Generally, in absence of Apt test, we would get Sepsis workup, PT, aPTT, platelets done and baby would also be given IV antibiotics, Vitamin K and possibly FFP.
But a Simple test can prevent unnecessary interventions when history is clear and baby is well.

Vomiting of blood mixed content on first day or two in newborn is a commonly encountered problem. In Neonates, swallowed maternal blood is the most common cause in case of suspected GI bleeding. Blood can be either swallowed during delivery or swallowed from cracked maternal nipples during breast feeding. 1. As gastric transit is quick, newborn even present mimicking hematochezia or malena.

A simple bedside test can rule out lot of confusion and prevent unnecessary intervention, specially when amount is significant and requires evaluation. Apt test is useful for differentiating between newborn swallowing mother’s blood and fetal gastrointestinal bleeding. One is a benign condition and other is a worrisome one.

How is Apt Test done?
- non-quantitative method based on resistance of hemoglobin F to alkali denaturation. This test is useful ONLY on frankly bloody (red) stool or gastric specimens, not tarry (black) specimens.

Concept is- Fetal Hb is resistant to alkali denaturation.

Color change in Positive and Negative test. Alkali Denaturation Test

- false-positive result as oxyhemoglobin has been converted to hematin. 
- Visual judgement of color produced by test procedure may lead to error if only a small amount of blood is present. 
-Bilirubin containing meconium and possibly other substances may cause stool color interference. 2

Other Diagnsotic consideration should be
Midgut volvulus
Sepsis- DIC
Early onset hemorrhagic disease of Newborn
Stress gastic ulcer
Traumatic bleed- NG or CPAP induced nasal or gastric mucosal bleed.

In a sick newborn, just relying on Apt test does not seem logical and detail work up is needed.

Saturday, March 11, 2017

Immunization in Children- Basic concept

Immunization is defined as the procedure by which the body is prepared to fight against a specific disease. It is used to induce the immune resistance of the body to a specific disease.

Immunization is of two types:
1. Passive immunization
2. Active immunization.

1. Passive Immunization Passive immunization or immunity is produced without challenging the immune system of the body. It is done by administration of serum or gamma globulins from a person who is already immunized (affected by the disease) to a non-immune person.
Passive immunization is acquired either naturally or artificially.

Passive Natural Immunization- Passive natural immunization is acquired from the mother before and after birth. Before birth, immunity is transferred from mother to the fetus in the form of maternal antibodies (mainly IgG) through placenta. After birth, the antibodies (IgA) are transferred through breast milk. 

Passive Artificial Immunization - It is developed by injecting previously prepared antibodies using serum from humans or animals. This type of immunity is useful for providing immediate protection against acute infections like tetanus, measles, etc.

2.Active Immunization

Active immunization or immunity is acquired by activating immune system of the body.  Body develops resistance against disease by producing antibodies following the exposure to antigens. Active immunity is acquired either ◦naturally or artificially.

Active Natural Immunization
Naturally acquired active immunity involves activation of immune system in the body to produce antibodies. It is achieved in both clinical and subclinical infections

Active Artificial Immunization
Active artificial immunization is a type of immunization that is achieved by the administration of vaccines or toxoids.

Vaccination : The process of distributing and administering vaccines is referred to as Vaccination.

Types of vaccine

1. Live-attenuated (weakened) vaccines

These vaccines contain modified strains of a pathogen (bacteria or viruses) that have been weakened but are able to multiply within the body and remain antigenic enough to induce a strong immune response. ( Replicating Ag). The varicella-zoster vaccine, oral poliovirus (OPV) vaccine, or yellow fever virus vaccine are some examples of this type of vaccine.

Advantage are- Single dose is sufficient for immunization

Heterologous vaccines:  a sub-group of live attenuated vaccines produced from strains that are pathogenic in animals but not in humans.
-confers protective immunity against a pathogen that shares cross-reacting antigens with the microorganisms in the vaccine.
-Example cowpox virus that protects against smallpox in humans.

2. Killed- Inactivated Vaccines

To produce this type of vaccines, bacteria or viruses are killed or inactivated by a chemical treatment or heat. This group includes for example the inactivated poliovirus (IPV) vaccine, pertussis vaccine, rabies vaccine, or hepatitis A virus vaccine.

- Repeated dosing required.

3. Sub-unit vaccines
Instead of the entire microbe, subunit vaccines include only the antigens that best stimulate the immune system. In some cases, these vaccines use epitopes: the very specific parts of the antigen that antibodies or T cells recognize and bind to.
Because subunit vaccines contain only the essential antigens and not all the other molecules that make up the microbe, the chances of adverse reactions to the vaccine are lower.
Eg Hep B vaccine

4. Toxoid Vaccines

These vaccines are used when a bacterial toxin is the main cause of illness. When the immune system receives a vaccine containing a harmless toxoid, it learns how to fight off the natural toxin. ( non replicating Ag). The immune system produces antibodies that block the toxin. E.g Vaccines against diphtheria and tetanus.

Routes of Administration
Deep subcutaneous or intramuscular route (most vaccines)
Oral route (oral BCG vaccine)
Intradermal route (BCG vaccine)
Intranasal route (live attenuated influenza vaccine)

Scheme of immunization

Primary vaccination
One dose vaccines (BCG, measles, mumps, rubella, yellow fever)
Multiple dose vaccines (polio, DPT, hepatitis B)

Booster vaccination
To maintain immunity level after it declines after some time has elapsed (DT, MMR
Periods of maintained immunity due to vaccines
Short period (months): cholera vaccine
Two years: TAB vaccine (typhoid-paratyphoid A and B vaccine)
Three to five years: DPT vaccine (diphtheria, pertussis (whooping cough), and tetanus)
Five or more years: BCG vaccine(Bacillus Calmette–GuĂ©rin is a vaccine against tuberculosis)
Ten years: yellow fever vaccine
Solid immunity: measles, mumps, and rubella vaccines


Monday, December 12, 2016

Jaundice in newborn baby: Parent's guide

Yellowish discoloration of skin and sclera, " Jaundice" is a commonly met problem for parents of newborn babies.  Jaundice is caused by increased level of bilirubin in blood ( serum). Many parents notice yellowness first in the eyes and face and are overly concerned about the problem while others who have previously parented a baby are convinced that even normal newborn babies developed certain amount of yellowish discoloration. Almost 70% of term babies and 80% of prematurely born babies develop some amount of jaundice but around 10% require medical intervention. This means most are physiological jaundice ie benign in nature.
However, since the consequences of severe jaundice leads to brain damage, it is important to differentiate the physiological from pathological jaundice.

Some Frequently asked questions by Parents?

A. When should I be concerned about jaundice?
Certain risk factors increases the chance that jaundice becomes severe needing timely intervention. The absence of these risk factors however does not rule out the chance of developing severe jaundice. Therefore assessment by a clinician whenever you are concerned about jaundice becomes vital.

  1. Jaundice developing within 24 hours of birth
  2. When mother blood group is Rh-ve or O blood group ( Rh and ABO incompatibility)
  3. Premature babies developing jaundice ( < 38 completed weeks gestation babies)
  4. Signs of underlying illness like vomiting, poor feeding, fever or low tempertature, fast breathing or poor breathing effort.
  5. Presence of bruises on body, swelling of scalp or blood collection on othersites.
  6. Intrauterine infections in mother ( TORCH infections)
  7. Family history of severe jaundice in previous infant
  8. Persistence of jaundice beyond 3 weeks.
  9. Passage of white stools.
B. Should I breast feed the baby with jaundice?
Breast feeding should be continued adequately. But in some instances of Breastmilk jaundice if decided by the Doctor, it may need to be switched to formula feed for 48-72 hours. This is decided by your pediatrician.

C. Should mother avoid turmeric or other food if baby has jaundice?
Mother need not abstain from any food. Baby's jaundice is not related to mothers food but is caused by bilirubin produced in baby's blood itself.

D. What will Doctor do to check the jaundice?
If the jaundice appears less from clinical visual assessment, doctor will simply advice you to follow up after few days. But it it appears high then he/she will perform some tests.
Jaundice can be checked by device from skin with out pricking for blood or by sending blood samples. Here are list of tests for jaundice.

E. If jaundice is severe, what are the treatments available?
There are 2 effective treatments.
  1.  Phototherapy- Blue/White light therapy under which babies are kept without clothes to decrease the bilirubin in the blood.
  2.  Exchange transfusion- Exchanging the blood of baby with another blood. 
Other modalities are drug therapy like Phenobarbitone etc that are all decided by doctor in special circumstances.

F. If my jaundiced baby required extensive management, what else will I need to do?
For severe cases, doctor will advice you to perform hearing evaluation on a later date, as high bilirubin can cause hearing defects.

G. What happens if significant jaundice is not treated?
If the level of bilirubin in blood crosses significant level, it may cross the blood brain barrier and affect the brain causing damage.
Therefore, whenever a concern of jaundice is there, a visit to a doctor is important and also if the baby has been discharged early from the Hospital, a quicker follow up with in days is required.

[Disclaimer: The article is intended for information purpose only and should not be used as replacement for Doctor's consultation. Please see a doctor whenever you are concerned about the baby]


Thursday, October 27, 2016

Nine interesting cases in Neonates

1. Sepsis presenting with Diabetic ketoacidosis like feature in Preterm neonate

A thriving preterm neonate had new onset sepsis with off color skin and poor feed tolerance. A work up for sepsis was sent and antibiotics were upgraded to 2nd line agents. Inotrope was added for tachycardia with poor perfusion. By evening, there was polyuria with >8ml/kg/hr of urine. We checked our list for any drugs and checked RBS- it was high, so GIR was decreased. By night, baby developed acidotic breathing with severe metabolic acidosis with high blood sugar and urine sugar + ketone +. Fluid corrections were started, and was managed with Infusion of Insulin. Over next 12-24 hours the blood sugar came down to < 150mg/dl. Insulin was stopped and there were no further episodes of hyperglycemia. HbA1c was normal. Baby did well with normal Head scans.
The most interesting thing was the Blood sugar in this baby reached upto 1500mg/dl with ABG ph- 6.9 and HCO3 upto 4meQ/L. 

2. Infective endocarditis in a preterm newborn:
A baby who was ventilated for poor respiratory effort at birth was extubated on day 4 but started developing features of Congestive cardiac failure in late 2nd week. Baby had murmur since Day 2 but we noticed changing nature of murmur and deteriorating cardiac functions. Baby was started on diuretics and also needed Digitalization. Baby remained CPAP dependent. ECHO was requested. Echo located vegetation in RVOT. The baby also had repeated anemia. In background of all these, we started the therapy for IE. Baby remained 50 days in hospital and was discharged with good feeding and weight gain. Adequate control of failure and will follow up soon for repeat ECHO.

3. IUGR baby with recurrent hypoglycemia : Congenital adrenal hypoplasia.
A male baby was transferred in for lethargy and low blood sugar. Despite all management and adequate control of sepsis, it was difficult to wean the baby from IV drip. In background of hyponatremia, hypoglycemia and dark stained genitalia, 21 OHP level was sent which came high and significant. As sample was sent at time of illness, a repeat sample was sent that confirmed CAH. Baby was started on steroid and weaned off IV. Baby was sent for Endocrine consult for optimal care.

4. Down Syndrome with Upper GI obstruction
In view of bilious vomiting and double bubble appearance on Xray, a preliminary diagnosis of Duodenal atresia was made. Baby was operated and on laparotomy has Annular pancreas. A duodenoduodenostomy was done.

5. Three cases of  severe Meconium aspiration with PPHN : Sildenafil magic
For a resource limited condition like ours where NO is a dream, so is HFV, we administered sildenafil. The baby's Oxygenation index decreased over next 12-24 hours and were quickly weaned off ventilators in 2-3 days. A renewed lives from lost hope. One thing that clinicians have to beware is, it can cause refractory hypotension and should be used with caution. It should be avoided in cases with hypotension.

6.  Recurrent SVT in neonate:
It was the first time, we had to use Adenosine in neonate. This was case in India during my course.

7. Corpus callosum Agenesis, ambigious genitalia with refractory seizure:
Baby had atypical genitalia. USG revealed Lissencephaly with corpus callosum agenesis. Baby developed refractory seizure and was difficult to control with 3 antiepileptics so was kept on midazolam infusion. Baby ultimately expired. This was also case seen in India.
Diagnosis was X-linked lissencephaly with absent corpus callosum and ambiguous genitalia (XLAG)

8. Congenital Diaphragmatic hernia to CCHD to Holoprosencephaly:
 A newborn was referred in suspicion of CDH. Baby was cyanosed at birth. On examination, the findings were inconsistent with diagnosis. Chest Xray ordered showed good delineation of diaphragm on both sides. A suspicion of Congenital heart disease was made. Examination showed a huge posterior and anterior frontanels with diasthesis of suture. Baby had mid-facial hypoplasia with depressed nasal bridge.  USG cranium was ordered as such that revealed, Holoprosencephaly. MRI was planned.

9. 1st TEF repair:
EA/TEF was first time repaired in our teaching hospital with success. Baby was taken on academic bed and all procedures was done free of charge. The baby has undergone esophageal dilatation few times and is thriving well. With no other organ involvement, we expect the baby will have near normal outcome. This was an endeavor of Pediatric surgery team Neonatology team, Pediatrics team and Ped Gastroenterologist. None of the less the anesthesia team.

These are some of interesting mention-able cases in last one year. Hoping to see more challenging cases in coming future.

Pediatrics and Neonatology Team, NMCTH
Pediatric Surgery and Anesthesia team, NMCTH
Ped Gastro- Dr S. Rimal
Residents, medical officers and NICU staffs
NICU Unit, Sir Gangaram Hospital
Dr Manish Sh , Gangalal Hospital

Thursday, October 6, 2016

New Ballard Score : How to use it correctly

Assessment of gestational age can be made postnatally by either Dubowitz Score or New Ballard Scoring system. In sick infants, examination of Anterior lens canpsule vascularity with a +20D lens can be useful in assessing gestation and it needs to be carried out within 24 hours of birth.

Dr Jeanne L Ballard developed a scoring system based on neurological maturity and physical maturity to assess gestational age of babies. We are all well aware of the charts and scoring system but still many of us are not able to score appropriately and assign gestation age accurately.

Here is the chart-

You can use online calculator as well
Download New ballard score here

The video below demonstrates the procedure of assessment.

When is the appropriate time to perform New Ballard score?
Performed between 30 minutes to 96 hours, ideally within 24 hours. However, studies have debated its validity up to 7 days.
For preterm babies < 26 weeks, it must be done in first 24 hours because on second day babies may suffer from consequences of prematurity.

In such a case, you have two options: Perform the remainder of the neuromuscular criteria, then assign a similar score to the popliteal angle and heel to ear. Wait 24 to 48 hours or until flexor tone has returned to the hamstrings and gluteus muscles, and repeat the assessment For breech deliveries, there may be flexor fatigue in 1st 24 hours so, NBS is performed after 24-48 hours to avoid lower score for lowerlimbs.

Assigning score and gesatational age
For scores between numbers on the grid, we interpolate as follows:
25 = 34 weeks
26 = 34 weeks
27 = 34 weeks
28 = 35 weeks
29 = 35 weeks
30 = 36 weeks

Record only completed weeks of gestation and not partial weeks.
If weeks by exam fall within 2 weeks of KNOWN maternal dates, preferably confirmed by early ultrasound, then the maternal dates are more likely correct.
If weeks by exam are greater than 2 weeks outside of maternal dates in either direction, then the clinical gestational assessment is more likely correct.

New Ballard Score, expanded to include extremely premature infants. Ballard JL et Al.
Essential Neonatology- Mathur
Validity of New Ballard Score until 7th day of postnatal life in moderately preterm neonates.
Sasidharan K et Al