Status of Growth Hormone/ Insulin-like Growth Factor-1 (GH/IGF-1) Axis and Growth Failure in Ataxia Telangiectasia (AT) (GHAT)
Ataxia Telangiectasia, Growth Failure
About this trial
This is an interventional diagnostic trial for Ataxia Telangiectasia focused on measuring GH/IGF-1, Ataxia telangiectasia (AT), IGF-1 Generation Test, Growth hormone
Eligibility Criteria
Inclusion Criteria:
- Have a diagnosis of AT
- Have no fusion of epiphyses/closed growth plates as determined by X-ray of left wrist and hand (special skeletal age film)
- Be between 3 years to 18 years old and have not completed puberty
- Consent to permit blood and/or tissue samples for storage
- Demonstrate growth failure: height below the 10th percentile for chronological age
- Have a primary care physician at home
- Demonstrate growth failure, defined as growth velocity (measured as linear growth) that is less than 5% to 10% of that expected for children of the same age group, over the past 12 months
- Willingness to remain hospitalized for several days
- Provide evidence of serum IGF-1 level performed within the preceding 6 months and the results fall below 25% range of normal limits for age
Exclusion Criteria:
- Have fusion of epiphyseal plates
- Be under the age of 3 years or have reached completion of puberty
- Have a serum IGF-1 level that is above the 25% range of normal limits for age
- Be above the 10th percentile height for chronological age
- Demonstrate any history of anaphylactic reaction or hypersensitivity to one of the GH formulation
- Have any active or suspected neoplasia
- Demonstrate signs of intracranial hypertension as evidenced by papilledema upon examination by fundoscopy
- Have any condition that, in the investigator's opinion, places the patient at undue risk by participating in the study
- Be unwilling to undergo testing or procedures associated with this protocol
- Have acute or chronic infections
- Have a hypersensitivity to one of the drugs: Clonidine hydrochlorid, Arginine hydrochlorid, Estradiol valerate, Somatropin
- Have a presence of bradycardia, cardiac arrhythmia, have symptoms of a sick sinus syndrome
- Suffer from depression
- Have acute or recurrent thrombosis
- Have acute liver diseases
Sites / Locations
- Children's Hospital, Goethe-UniversityRecruiting
Arms of the Study
Arm 1
Experimental
Growth hormone-testing (GH/IGF-1-testing)
Patients (girls over 8 years and boys over 10 years) are primed with estradiol 1 mg orally for 2 days, to help avoid false results of growth hormone (GH) levels in blood samples. Then provocation testing is done, with two tests back to back. It determines blood levels of GH and the body's response to testing with drugs called arginine and clonidine. Patients are admitted to the pediatric inpatient unit and will have an intravenous (IV) line placed in the arm. Arginine is given by IV over 30 minutes, and blood samples are taken as indicated. The next day, the clonidine test is performed according to current guidelines. Then the IGF-1 generation test is done to see if the patient has the ability to generate IGF-1 in response to injections of GH for 5 consecutive days.