Table 1.

Summary of the clinical data

Patient	V	A	C	TE	R	L	Other features
1	no anomalies (distal kinking on spinal MRI)	none	VSD	TEF with distal EA	abnormally echogenic kidneys bilaterally, with atrophic right kidney	none	none
2	multiple dysplastic supernumerary lumbar vertebral bodies, left cervical rib, 13 R ribs	anal atresia	none (history of PDA and PFO)a	TEF with distal EA	no frank anomalies; grade I VUR and chordee	none, though mild UE asymmetry	only consistent with prematurity

Twin pair 1 has additionally been described in Solomon et al. [2011]. EA = Esophageal atresia; PDA = patent ductus arteriosus; PFO = patent foramen ovale; TEF = tracheo-esophageal fistula; UE = upper extremity; VSD = ventricular septal defect; VUR = vesicoureteral reflux.

^aHistory of PDA and PFO is supposed to be most likely related to prematurity rather than reflective of a true congenital cardiovascular malformation.