Low White Cell Counts: Naomi's Next Challenge

I'm spending another afternoon waiting for test results today. Naomi's white blood cell counts have been progressively dropping over the last five months. White blood cells counts are supposed to be between 5.2 and 14.8 K/mm3. In February Naomi's levels were 4.7, in May 3.6, and in June 3.0. In June Naomi had a terrible time getting over a stomach virus that went through our family. She had awful diarrhea for a week and lost four pounds, then was excessively tired and listless with low appetite for another two weeks. This is almost certainly due to her body's lowered ability to fight infection without the proper number of white cells.

We had another Complete Blood Count drawn yesterday, and I am anxiously awaiting word now. It's difficult not to speculate about what all this means. I have a detective's mind that is endlessly trying to draw connections to help understand my daughters better. Sometimes this gets me in trouble, but sometimes I am right and my thoughts prove valuable to helping the doctors treat my children. As writing seems to be my best therapy, I'm writing out my thoughts today.

I was told that if the counts dropped below 3.0 at all it would be considered dangerously low and we'd be referred to a hematologist for follow-up. The most likely explanation for the low count is that Naomi's liver fibrosis has progressed to where the blood in the portal vein cannot easily flow though the liver, causing portal hypertension (high blood pressure in the portal vein). This is an extremely common result of congenital hepatic fibrosis. The pressure in the portal vein causes the spleen to enlarge and small blood vessels in the esophagus may burst, causing life-threatening bleeding. The spleen under pressure may begin to sequester or trap platelets and/or white blood cells. Typically an enlarged spleen with low platelet counts are the first signs, but a slightly enlarged spleen with only low white counts can be the first sign as well.

Obviously, there are other explanations for low white cell counts including immune-system disorders where white cells are destroyed in large amounts (since Naomi has one auto-immune disease already this is not entirely out of the question), and bone-marrow disorders where white cells are not produced in sufficient quantities. However, I think the theory of the spleen trapping the white cells because of portal hypertension is most likely.

If this proves to be the case we are probably looking at four options:

1) Shots of a medicine that forces the bone marrow to produce more white cells, though if the spleen is just going to trap these again this seems an unlikely solution.

2) Surgery to place a shunt from the portal vein to another major vein. This allows some of the blood in the portal vein to be rerouted off of the backed-up portal "highway" to a less-crowded side road that leads to the body's main "interstate highway." This is an effective way to relieve pressure on the spleen and the vessels in the esophagus. It is proven effective at restoring blood cell counts and preventing esophageal bleeds. The problem is that the blood in the portal vein was bound for the liver for a reason: it is full of toxins that need to be filtered out by the liver before being released to the rest of the body. When a shunt sends portal vein blood to the main vascular system again these toxins can reach the brain and cause slowed brain waves (hepatic encephalopathy) in 1/3 of shunt patients. Naomi has enough issues with clear thinking already; I am not anxious to add encephalopathy to her troubles.

3) Removal of the spleen. This would restore normal blood counts, but does not lower pressure in the portal vein and so does not prevent the life-threatening esophageal bleeds. When the spleen is otherwise healthy and normal sized this is often not the option of choice.

4) Liver transplantation. Now that organ transplantation is becoming more common and successful, and now that it is possible to transplant one lobe of liver from a living donor this is fast becoming the treatment of choice. The fibrosis does not recur in the donor liver, portal vein pressure is restored to normal, the spleen can remain intact, blood counts return to normal, and there is no longer a risk of esophageal bleeds or the liver infections that often plague kids with hepatic fibrosis. Of course, there are the draw-backs of major surgery for both donor and recipient, life-long immune suppression therapy for the recipient, and the possibility that the liver may be rejected or may need to be retransplanted later in life.

As I wait for the phone to ring, none of these options sound appealing to me. I would like to hear that Naomi's white cell counts have inexplicably returned to normal levels and that no further follow-up is needed, but that probably isn't what I'm going to hear. I will post again when I have more information.