A boy with Weyers-like ulnar ray/oligodactyly reduction limb defects and split hand malformation: case report.

Summary: A boy with Weyers-like ulnar ray/oligodactyly reduction limb defects and split hand malformation: case report: Weyers ulnar ray/oligodactyly syndrome is characterized by variable ulnar, radial, or fibular ray limb reductions, single central incisor, and renal, splenic or cardiac anomalies. Split hand/split foot malformation is a central reduction defect of the hands and feet, and may occur either as an isolated malformation or as a part of syndrome. We describe a patient with Weyers-like ulnar ray/oligodactyly reduction limb defects and split hand malformation. Key-words: Ulnar aplasia - Split hand malformation - Oligodactyly. INTRODUCTION Reduction defects of the ulnar ray are very rare with an incidence of 1:100000 (17). They can occur as an isolated defect or as a part of multiple congenital abnormality syndromes. In 1957, Weyers (16) described two unrelated children with ulnar ray deficiency: one with a single central maxillary incisor and hypoplastic mandible; the other with cleft lip and palate, fibular ray reduction, and renal and splenic abnormalities. In 1985 Elejalde et al. (3), applied the Weyers' eponym to a lethal malformation in two sibs with ulnar and fibular ray deficiencies and hydronephrosis, proposing autosomal recessive inheritance. Congenital limb reduction defects occur in approximately 1 :2000 live births, among which the anomalies of the central ray constitute an important subgroup (1). The Split- Hand/Foot malformation (SHFM), also known as ectrodactyly, affects the distal portion of the upper and lower limbs, and is characterized by a deep medial cleft and missing central fingers (2, 4, 12). Genetically, SHFM comprises both isolated and hereditary forms, linked to five distinct loci (10, 11). CASE REPORT A boy was born at term and was the first child of non-consanguineous parents, aged 28 (father) and 24 (mother). He was referred at 4 years of age. On examination he had an absent fifth finger on the right hand and left split hand deformity (Figs IA, IB). Radiographs showed absent left ulna, and absent fifth finger ray and fifth metacarpal bone of the right hand (Figs 2A, 2B). There were no apparent midline facial, oral and tooth anomalies. His echocardiography, and chest radiograph were normal. Ultrasound screening did not find any internal organ abnormalities. Laboratory examinations and karyotype analysis were also normal. DISCUSSION Isolated ulnar ray defects appear to be reported less frequently than ulnar ray/multiple congenital abnormality syndromes (5-8). Midline abnormalities occur frequently within the ulnar ray/multiple congenital abnormality syndrome group (9, 14), suggesting the possibility of a common developmental field of the ulnar ray and midline. Familial SHFM is generally inherited as an autosomal dominant trait with reduced penetrance and variable expressivity both among and within affected families and even among the autopods of a single individual. We report a patient with an absent fifth finger of the right hand and left split hand malformation. He had no apparent midline facial anomaly. This seems to be an unusual association of Weyers-like ulnar ray/oligodactyly syndrome and split hand malformation that has not yet been described. The association of midline developmental anomalies with ulnar/radial ray reduction limb defects, and phocomelic syndromes suggests an intimate but as yet undefined embryological relationship. The processes which determine symmetry in the midline plane of the early embryo may therefore interact, or have a common developmental link, with the way in which mesenchymal condensations arise from the mesoderm to form the limb buds. …