Wednesday, November 28, 2012

Short(ish) Update - Brain dump #2

I got an email back from GI that said the high HR could have been from feeding, but not the temp. However, if Tomas had some sort of infection/illness going on he would expect the fever to go down with a decrease in feeds (a.k.a. - stressing his body out). As long as Tomas doesn't run any more temps of 100.4 or greater we are in the clear. Nothing since Mon. night so we are good to go!

Saw infectious disease today. This is the first time Tomas has been seen by that service as an outpatient. Went through history, previous test results, pending tests, and such. He was particularly interested in the Shwachman-Diamond syndrome possibility. He said that there is a slightly higher prevalence of the disease in the DS population, and that clinically Tomas meets the criteria for the disease. The 3 criteria for a clinical diagnosis are:
1. Chronic Neutropenia (not otherwise specified)- check
2. Chronic Anemia (not otherwise specified)- check
3. Exocrine Pancreatic Insufficiency - semi-check. This enzyme insufficiency causes malabsorbtion issues in the GI tract and particularly fat malabsorbtion issues. Tomas definitely has fat malabsorbtion issues but I've always assumed it was due to his gallbladder being removed, and as far as I can recall no one has checked for other reasons.
There is a 4th component of skeletal abnormalities but it is not seen all the time and is not a part of the clinical criteria for the disease. The doctor said that skeletal issues can also take years to appear (like delayed bone age)  so it is not considered a necessary finding for the diagnosis.
I don't know, it is not a perfect fit and I like for things to fit neatly. That's why I never thought Down syndrome alone could explain Tomas. I said as much but the ID doctor said that with the pancreatic enzyme insufficiency sometimes has to get as low as functioning at 10% of normal before it shows up, and it just may be that Tomas is still young and his pancreas is still functioning well enough to stay above radar. He went so far as to say he was going to go out on a limb and say Tomas has Shwachman-Diamond. Eh...every single diagnostic test Tomas has ever had has come back either negative or inconclusive so I really can't get to excited about this yet. In the bizare world of my son where having a diagnosis of Shwachman-Diamond would be something to get excited about that is!

As for the immune component - here's where things get complicated. I needed a picture, for real.

Ok, white blood cells are made up of a few different types of cells: neutrophils, lymphocytes, and a few others that don't apply for Tomas' case.
We know he makes plenty of neutrophils (because his bone marrow biopsies show adequate baby neutrophil numbers).
We also know he makes tons of lymphocytes (his lab results are always on the high end).
There are two main types of small lymphocytes - T cells and B cells. B cells are responsible for producing immunoglobins, which in turn fight off infections. Tomas has had his immunoglobins tested several times. He was deficient in one up until he was about 2. Since then his counts have been normal. BUT Tomas has never had his T cells tested, and as it turns out one particular type of T cell (called CD4 or Helper cells) is responsible for directing the majority of infection fighting white blood cells.
This is where the doctor wants to focus. He thinks that Tomas either has a CD4 deficiency or a CD4 malfunction. Without Helper cells telling them what to do the other cells don't know to fight off an invader, regardless of what the blood counts show. First up is to test the T cell count, then he will test their function. This one I am excited about as it would explain why Tomas gets sick so often, why everything in his bone marrow points to an autoimmune disorder, but the autoimmune testing is always negative.

Next up for the appointment was the bacteria Tomas is persistently growing in his urine. It is already resistant to one major antibiotic family, and the dr said it would likely become resistant to the antibiotic Tomas is on now, which is why he does NOT want to put him on prophylactic antibiotics to prevent any more UTIs. This totally stinks, since urology is not going to move on preventing UTIs until the urodynamics study - which is in January. Which leaves Tomas completely exposed to another illness/hospitalization. He did say that he felt the bacteria was colonized and that it likely is colonized in the stones, which makes them very hard to break up and typically they need to be surgically removed. Which is pretty much what urology said yesterday. He also said that IF Tomas should get another UTI that he would recommend putting him on prophylactics until the testing. I hate that approach - I can't even tell you how much - but it is one I've encountered over and over across every specialist Tomas sees.

See - this was a shorter update right?



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