Cat eye syndrome, anorectal malformation, and Hirschsprung's disease.

Sir,

The estimated incidence of anorectal malformation (ARM) associated with Hirschsprung's disease (HD) is 2.3%-3.4%, about 1/147,000 live births.[123] Furthermore, occurrence of HD and ARM in a patient with cat eye syndrome (CES) is very rare, with only three cases reported in available English literature.[145]

This female newborn with a normal vaginal delivery, full term, and birth weight was 2.100 kg, with the following abnormalities: imperforate anus (with anovestibular fistula), left ptosis, bilateral iris coloboma, and skin tags in right preauricular area and cheeks. At age of 20 days, a sigmoid colostomy was performed, and later at the age of two months she underwent posterior sagittal anorectoplasty (PSARP). Because of health insurance issues, closure of the colostomy was not done until the age of 18 months. During this period, she had problems with passing stools, she was constipated, and required frequent saline enemas (2-3/day), and she thrived poorly. All of the fore mentioned was blamed on the colostomy construction and frequent dilatations were performed. Following closure of colostomy, she experienced multiple episodes of severe constipation requiring hospital admission to manage it. At that time, the presence of HD was suspected, so a contrast study was preformed showing significant dilation of small and large intestine. This was differentiated from stricture at the site of closure of colostomy, a rectal biopsy was planned. Unfortunately, the patient was admitted with severe sepsis associated with intestinal obstruction, toxic megacolon for which an emergency laparotomy was undertaken when an obvious transition zone was seen in the terminal ileum [Figure 1]. Both ileostomy as well as colostomy at the site of previous anastomosis were created, as well as multiple small and large bowel biopsies were taken.

Figure 1

Transitional zone in the terminal ileum

The patient was admitted to the intensive care unit because of hypothermia and hypotension that attributed to septic shock, and she died on the 2nd day after operation despite maximal resuscitation efforts.

The biopsy showed absence of ganglion cells in all biopsies taken till 15 cm proximal to the ileocecal valve.

ARM is a wide spectrum disease, ranging from simple malformations with good prognosis, to very complicated ones, associated with multiple anomalies of different systems. ARM represents one of the major features of CES, observed in about 83% of cases.[6]

HD tends to be either an isolated entity, or it may occur as part of syndromes in 30% of HD cases. Regarding its occurrence with ARM, Watanatittan et al.,[3] reported nine cases of HD associated with ARM, representing 2.8% of 321 HD cases.

In regards to the association between CES, ARM and HD, only three case have been reported in the literature, two cases were associated with long segment HD[15] and the third one associated with short segment HD[4] [Table 1]. This makes our case the fourth one. This association opens the discussion regarding the possible presence of gene at the chromosomal region 22q11.2, responsible for the enteric system development, the same chromosomal region which its abnormalities can cause CES.[4]

Table 1

Comparison between the present case and the previous three cases

This case emphasizes the awareness of suspecting the presence of HD in a patient with managed ARM, who has recurrent episode of constipation and fecal impaction. Moreover, this suspicion should be higher when dealing with ARM as part of CES. Further investigations are required to identify the true role of chromosome 22 regarding this unique association and its relation to the development of the enteric system.