Recently, I read with great interest the papers/ editorial comment by Martı ´nez-Frı ´as et al. [2001], Keppler-Noreuil [2001], and Carey [2001] on cloacal exstrophy and OEIS (omphalocele -exstrophy -imperforate anus -spinal defects) complex. These papers demonstrate again the ongoing difficulties in terminology and delineation that, if possible, should preferentially be based on causes. However, because they are presently still unknown, terminology is based on phenotype and conclusions. This leads to a variety of names and confusion on how to classify a given complex of malformations including ''bladder exstrophy'' as a main finding. Martı ´nez-Frı ´as et al. [2001] have pointed out that bladder exstrophy and cloacal exstrophy seem to be distinct clinical entities.
Exstrophy of the cloaca is a well-known malformation that includes the persistence and exstrophy of a common cloaca that receives ureters, ileum, and a rudimentary hindgut and is associated with failure of fusion of the genital tubercles and pubic rami, incomplete development of the lumbosacral vertebrae with spinal dysraphism, imperforate anus, cryptorchidism and epispadias in males and anomalies of mu ¨llerian duct derivates in females, and a wide range of urinary tract anomalies. Omphalocele is common, and most patients have a single umbilical artery [Smith, 1997]. Thus, the term ''cloacal exstrophy'' is not restricted to the namegiving finding but includes omphalocele, imperforate anus, and spine anomalies (the O, I, and S in the OEIS acronym) as well as renal and umbilical cord anomalies, per definitionem.
In 1978, Carey et al. reported on a number of cases, of which all but one met the clinical criteria of ''classic'' cloacal exstrophy. They introduced the term OEIS