Fanconi anemia (FA) is a hereditary progressive bone marrow failure syndrome and patients may have various endocrinological problems. In this study, we aimed to determine the rate osteopenia/osteoporosis in patients with FA below 18 years-old and tested the use of urinary deoxypyridinoline for this purpose in comparison with bone mineral densitometry (DEXA) measurements. Seventeen DEB positive FA patients (females/male; 9/8, mean age; 10.6±3.5 years (5-17)) were evaluated with urinary deoxypyridinoline and DEXA measurements from L2-L4. The Z score of DEXA were corrected according to body surface area, age and gender. Urinary deoxypyridinoline was found 17.6±10.5 nMDPD/mM (range among FA: 4.5-47.5, normal range for healthy group: 3-7.4). The mean corrected Z score values were -1.45±1.2 (+0.51 to -4.22). Eight (47%) were found to be osteopenic (Z score -1 to -2.5) and 3 (18%) had osteoporosis (Z score below -2.5). All of the patients who had osteopenia or osteoporosis had urinary deoxypyridinoline above the normal limits. Of the 6 patients with normal Z scores, 4 (66.6%) had deoxypyridinoline levels above the normal range. Osteopenia/osteoporosis is a common problem in pediatric and adolescent patients with FA (64.7% via DEXA in our study). Urinary deoxypyridinoline is found to effectively catch the patients who are osteopenic/osteoporotic in consistence with DEXA. In 66.6% of patients with normal DEXA levels, the urinary deoxypyridinoline levels were higher than normal and this may indicate that urinary deoxypyridinoline can detect the bone mineral density decline earlier than DEXA.

Keywords: deoxypyridinoline, Fanconi aplastic anemia, osteopenia