Sickle Cell disease in pregnancy

 

Sickle Cell disease in pregnancy

 

Sickle Cell disease is a genetic disorder of hemoglobin.

In this disorder instead of normal hemoglobin A,the bone marrow produces abnormally structured hemoglobin-S.

Because of this hemoglobin-S, the shape of red blood cells become distorted

These distorted RBCs, when they pass through reticulo-endothelial system, they get destroyed in larger numbers.

The by-product of this destruction lead to elevation of unconjugated hemoglobin in the blood. There is also secretion of urobilinogen in urine making the colour of urine dark yellow.

Clinically patient present as jaundice and chronic anaemia.

Body will try to correct this anaemia by making more red blood cells.

These immature red blood cells are known as reticulocytes.

In peripherals smear of blood reticulocytes count will be increased.

Because of this increased metabolism, a liver enzyme LDH is also increased in blood.

This disease is characterized by life threatening vaso-occlusive crisis.

What happens is this- the abnormal shaped RBCs, when they pass through micro vasculature of any organ, they stuck over there.

This leads to situation of micro infarction in the system.

To understand it more fully, you can imagine that the blood stops flowing after a certain point.

It creates paucity of oxygen in the end organ.

If this phenomenon is happening in vital organs like brain, lungs or heart, it can be life threatening too.

If a woman has Sickle Cell disease and she becomes pregnant then following consequences may happen.

She may have vaso -occlusive crisis. It means micro or macro infarcts can lead to organ damage.

She may have anemia crisis with severe haemolysis, red cell aplasia and splenic sequestration.

Acute chest syndrome can become a cause of maternal mortality .

Neurological events can also complicate her journey.

Now let's talk about each event in a bit of detail.

Vaso-occlusive crisis or painful crisis is the most common reason for hospital admission.

Mostly, pain occurs in third trimester & post-partum period.

Most common site is head of femur & humerus. And pain occurs because of osteonecrosis of bone marrow.

In acute haemolytic anemia, Red blood cells get sequestered in spleen leading to its rapid enlargement and abdominal pain.

In acute lung injury two things happen-one, fat embolism from bone marrow and two vao-occlusive crises.

Patient presents with chest pain, increased respiratory rate associated with respiratory distress and abnormal pulmonary function test.

X-Ray show pulmonary infiltrates.

Neurological events may cause fits in the pregnancy.

Course of pregnancy is complicated for women having single cell disease.

Firstly, there are higher chances of spontaneous abortion.

Most of the complications are related to vaso-occlusion, the result of which is decrease blood supply in placental bed as well as to the foetus.

Following is the list of maternal complications-

-Cerebral vein thrombosis

-Deep rain thrombosis

-Pulmonary embolism

-Pregnancy induced hypertension

-Eclampsia

-Pre term labour

-Placental abruption

Foetal complications include-

-Intrauterine growth retardation

-Pre term labour

-Prematurity

-And even intrauterine fetal death

Care of these women during pregnancy should be done in a tertiary care centre where a team of doctors like gynaecologist, haematologist, paediatrician, blood bank, ICU and NICU are available.

Frequent monitoring of patients with multiple blood tests and ultrasound will be required.

Fetal well being will also need to be monitor more closely by use of ultrasound, colour Doppler and NST.

The patient may require multiple hospital admissions to manage Sickle Cell crisis.

She may also require blood transfusions.

Baby delivery may happen prematurely for various reasons and baby may also be low birth weight requiring NICU care

Challenges are many but with advanced medical care it is possible to keep both mother and baby safe.