Trichothiodystrophy; Bone Abnormalities; DNA Repair; Transcription Disorder
Objective(s): The purpose of the study conducted is to characterize the qualitative and quantitative features of the bone abnormalities present in patients diagnosed with Trichothiodystrophy (TTD), a DNA repair and transcription disorder. An additional goal of the study is to identify TTD patients at risk for rapidly progressive bone abnormalities in order to improve diagnosis and treatment for TTD patients.
Study Design: A retrospective study conducted at the National Institutes of Health (NIH) examining the bone abnormalities present in a study population comprised of 32 patients between the ages of 1 and 29 years of age diagnosed with TTD. Radiographic images, acetabular angle, walking ability and stage of avascular necrosis (AVN) were evaluated to assess changes in bone structure.
Results: Delayed bone age, central osteosclerosis, peripheral osteopenia, hip degeneration or coxa valga were present in 31 (97%) of 32 TTD patients. All TTD patients with hip abnormalities on radiographic images exhibited progressive degeneration and difficulty walking, over a 2-6 year period. Acetabular angle measurements did not correlate with the clinical and radiological findings for 4 (80%) of 5 TTD patients with hip abnormalities on radiographic images. Abnormalities in mean corpuscular volume (MCV), hemoglobin A2 (HbA2), red blood cell morphology and hormone and nutrient levels (calcium, parathyroid hormone and Vitamin D) were not associated with the onset of bone abnormalities present in the 32 TTD patients.
Conclusion(s): Bone abnormalities are a common clinical feature of TTD that have been shown to significantly impact the quality of life of a TTD patient. Thus, analysis of the predictive factors and events preceding the onset of bone abnormalities is clinically important in improving the diagnosis and treatment of TTD.
Allawh, Rina; Xiong, Michael; Tamura, Deborah; DiGiovanna, John J.; Collins, Michael T.; Kraemer, Kenneth H.; and Hill, Suvimol, "Skinning the Surface of Bone Abnormalities in Trichothiodystrophy" (2013). GW Research Days 2013. Paper 10.