June 6, 2010 – Tristan had his quarterly endocrine appointment with Dr. Emily Germaine-Lee the lady who specializes in people with Albright Hereditary Osteodystophy (AHO). His overall endocrine-associated levels look good, but she is concerned about his overall slow growth. It was six months since his last appointment and according to her charts he has not gained in height or weight significantly. This is not normal for what should be a growing three-year-old.
The reason she is concerned is that 70% of the AHO patients with whom she has worked or researched have issues with their growth hormone levels. If left untreated Tristan will be lucky to even reach five feet tall, which of course for a man is rather short. In AHO, the bone growth plates fuse at an earlier age than children without the condition. As I stated in an earlier post, Tristan is very rare in terms of where on the GNAS gene the mutation occurred. As a result, Tristan’s expression of AHO is different than most other children with the disorder. As we discovered, his condition is much less severe than it could be, so we are thankful he had the mutation where he did. Most children with AHO have resistance to Thyroid-Stimulating Hormone (TSH) and to Parathyroid Hormone (PTH). At this time Tristan only has resistance to TSH, but not to PTH. Also, most AHO children are obese and often have obesity-associated conditions like diabetes. Tristan is the exact opposite in that he is skinny and has difficulty in weight maintenance. This has been true since his birth. Dr. Germain-Lee thinks there could be something interesting going on, but she is not sure what it is at this point.
So, sometime this summer Tristan will need to fast and have a growth hormone stimulation test conducted. An intravenous line will be placed in his arm, and over a three hour period they will inject an amino acid called arginine. At about every 30 minutes they will take blood samples. This will tell her if he is sufficient or deficient in his growth hormone production ability. If he is deficient, he will definitely go on growth hormone therapy to help improve his growth rate. She has done growth hormone treatment for many years, and now eight of her patients have reached adulthood, the tallest is about 5′ 7″, which she says is still short probably for a male, but is within the low-normal range.
She also plans to measure a number of other blood parameters to check his immune system and some other things she wants to determine. It will not be a fun day for him, but I hope it will give us answers on how to help him in the future.
Dr. Germain-Lee was very pleased about his progress with speech and other developmental milestones. I feel a bit relieved, because I noticed too he has virtually ceased in his growth. He does not advance beyond 30 pounds in weight and 33 inches in height for about a year now it seems. He has worn the same 2T/3T clothes and shoes the entire time.
So thank you again to all of you who follow Tristan, and his/our story. He is a precious boy who has so much promise.