Aphalangia, Partial, With Syndactyly And Duplication Of Metatarsal Iv

Clinical Features

Martinez-Frias et al. (1995) reported a Spanish family in which the father and a daughter and son had partial aphalangia, syndactyly with duplication of metatarsal IV, microcephaly, dull intelligence, and short stature. Although the types of limb anomalies described in this family had been observed previously, they had occurred as isolated defects or in association with other defects. Thus, Martinez-Frias et al. (1995) concluded that this is a newly described autosomal dominant syndrome.

Di Rocco (2002) reported a 17-year-old boy, born of consanguineous parents, with borderline mental defect (IQ of 75), distal aphalangia affecting both the hands and feet, and duplication of metatarsal IV. He also had severe kyphoscoliosis and megaureter, which may have been coincidental. His parents and 2 brothers were unaffected.

Utine et al. (2009) reported a 10-year-old Turkish boy, born of consanguineous parents, with distal extremity anomalies, microcephaly, and impaired cognitive function (IQ of 50). He was tall and obese with normal hands and fingers. However, his feet showed multiple distal skeletal defects, including 3 toes on the left and 4 on the right, partial cutaneous syndactyly between the second and third digits, several overriding toes, and duplication of metatarsal IV.

Ozsurekci et al. (2015) reported a 12-year-old girl, born of consanguineous parents, with microcephaly, borderline intelligence, partial distal aphalangia, syndactyly, and duplication of metatarsal IV. She also presented with a massive cerebral sinovenous thrombosis. Hypercoagulability risk was assessed in the patient, but no clear risk factor was identified.

Inheritance

The transmission pattern of partial aphalangia with syndactyly and duplication of metatarsal IV in the family reported by Martinez-Frias et al. (1995) was consistent with autosomal dominant inheritance. In contrast, the individual patients reported by Di Rocco (2002), Utine et al. (2009), and Ozsurekci et al. (2015) were all born of consanguineous parents, suggesting autosomal recessive inheritance, but a de novo dominant mutation could not be ruled out.