Hyperpigmented Macules: Fanconi Anemia

This is an autosomal recessive syndrome characterized by chromosomal breakage, pancytopenia, and various congenital abnormalities. It is a heterogeneous condition clinically and has been linked to defects in at least 8 different genes. Fifty percent to 65% of affected persons demonstrate areas of hyper- or hypopigmentation. Café au lait macules, like those shown in Figure A in a 9-year-old boy, are seen in approximately 25% of those affected.

Skeletal abnormalities are another hallmark of Fanconi anemia: hypoplasia of the thumbs and radii are the most common findings. Figure B demonstrates hypoplasia of the thenar eminence in the same 9-year-old boy. Other skeletal abnormalities include hip dislocation, scoliosis, and vertebral anomalies. Low birth weight and subsequent short stature, microphthalmia, microcephaly, developmental delay, renal and genital anomalies, GI defects, and cardiac defects also have an increased association with this condition. However, 1 out of 3 affected persons demonstrates no obvious congenital deformities.