If as a surgeon you have had a working relationship with a colleague for more than twenty years, it is not uncommon to take certain things for granted when he invites you to come and help out. Things like leaving the patient on the operating table and asking the assistant to write up the operation notes while you take a walk becomes commonplace. On certain occasion, the patent is already on the table and on arrival you go straight for the procedure without even saying hello to the medical director(MD) of the hospital. This day was no different. He had been informed of an elective caesarian section the previous day. When he asked of the indication, the reply of the MD was that her first confinement was through a caesarian section. So, there was no big deal.
On arrival, the surgeon went in for what he thought would be a simple caesarian section. The shocker came when the baby was brought out; there was no life in him. The first impulse was to go for the pericardial area to feel for the heart beat; and it wasn’t there! To make the matter worse, the skin of the dead baby was already peeling off. The umbilical cord was rotten and the liquor was heavily stained with meconium. In clinical terms, it was macerated still birth, meaning that the baby had been dead for more than 48 hours and no one raised an alarm. Well, operating to remove a dead baby is not a misnomer in practice and actually be a life saver in most instances. But a pre operative diagnosis helps everyone to know what they are getting into.
Now to the crux of the matter; the patient had Rhesus disease(RhD). This lesion goes by various names like rhesus incompatibility, rhesus D haemolytic disease of the newborn, rhesus isoimmunization, erythroblastosis foetalis and so on. This disease results in the destruction of the red blood cells of the baby while still in the womb. Basically, it is an immunological disease that manifests when a mother’s blood is incompatible with that of the baby with respect to the Rhesus factor antigen. In the general populace, there are those who have RhD gene and have the RhD antigen expressed in their red blood cells. If you are one of those; then you are said to be RHESUS POSITIVE. But if you do not have this antigen in your red cells, you are said to be RHESUS NEGATIVE.
The rhesus phenomenon comes into play when a rhesus negative mother conceives a baby who is rhesus positive. During the process of delivery or termination of the pregnancy, the maternal and foetal blood does mix. The foetal blood on entering the maternal circulation would be treated as a foreign body due to the presence of RhD antigen. The maternal immune system would in turn produce antibodies designed to attack and destroy the foetal red cells. Note that this only becomes evident in subsequent pregnancies irrespective of how the index pregnancy ended; be it normal delivery at term, ectopic pregnancy or even an abortion.
Thus during subsequent pregnancies of RhD positive foetus, antibodies from the mother with low molecular weight especially the IgG (immunoglobulin G) cross the placenta barrier and attack the red blood cells of foetus leading to their destruction. This condition can be mild, moderately severe or severe. During the process of red cell destruction, the foetus tries to compensate by increasing the rate of red cell production leading to increased presence of immature red cells known as ERYTHROBLASTS in the foetal circulation. This condition is known as erythroblastosis foetalis. In extremely severe case, Rhesus disease can lead to foetal intra uterine death with accumulation of fluid in the babies and when delivered are noted to be bloated; a condition known as HYDROPS FOETALIS.
In our environment, best way to cope with this condition; which has paid off to a large extent, is not by doing tests to confirm the presence of anti D antibodies in the maternal or foetal blood, but to assume that once a woman is Rhesus negative she is already sensitised. Thus, it is routine for all Rhesus negative mother to be given anti-RhD antibodies to mop up any Rhesus antigen that may have crossed the placenta barrier into the maternal circulation from the foetus. This is done at twenty eight weeks of gestation. It is almost mandatory that expectant Rh negative mothers arrange for RHOGAM brand of IgG months before confinement that would be administered as soon as the baby is delivered. This aggressive approach has been of tremendous help in the management of Rhesus phenomenon.
Having said this, much there are tests to detect antibodies and their level in the blood of the patients. The most commonly performed test is INDIRECT COOMBS test in which blood is taken from the mother to test for the presence of IgG antibodies that may crossed the placenta into maternal circulation. This is usually a prenatal and pre blood transfusion- for the baby- test. The DIRECT COOMBS TEST is for the baby when an auto immune haemolytic anaemia is present.
In our environment it is routine that in all cases of jaundice in the newborn that requires exchange blood transfusion, the mother’s blood will be tested irrespective what the blood group or Rh status is. There are other blood tests that are of importance in the management of this condition like estimating the level of SERUM BILIRUBIN, a toxic product from red blood cell breakdown that causes yellowish discoloration of the whitish part of the eye and skin, white cell count, platelet, hemoglobin and so on. These enable the caregivers to determine preferred management options to be considered. Ironically in our environment the commonest neonatal scourge is sepsis. Even when the baby is obviously jaundiced, infection is still considered top on the scale of differentials before considering challenges like prematurity and small for gestational age
In a resource constraint environment especially with challenged laboratory back up, in severe jaundice and neonatal anaemia, phototherapy and exchange blood transfusion is the gold standard. Antibiotics are given to the babies routinely and n some centres the babies are treated for ‘transfusion Malaria’. These babies are kept under close watch until the level of the serum bilirubin is down to a safe value.
This specialized health care is better left in the hands of a paeditrician. Suffice it to say that in established Rhesus negative mother, eternal vigilance through antenatal period to delivery and the first month of life.
Thus it was unthinkable that in our index case no one who had anything to do with the baby raised an alarm. What an embarrassing goof.