Posterior cloaca was first described by Leditschke and Pena.4
The term posterior cloaca was suggested by Pena and Kessler.3
Three anatomic variants of this defect are described: (A) fused urethra and vagina open into the anterior rectal wall, at the anus and is visible only endoscopically; (B) the urogenital sinus opens into the perineum immediately anterior to the anus; and (C) the urogenital sinus opens either in the rectum or the perineum and there is a rudimentary urethra opening at the tip of a pseudophallus (as in our case).3
By definition, our case fits the type C defect.
We called it reverse cloaca because it is simply the reverse of the classical persistant cloaca. Posterior cloaca is a rare anomaly but, in this patient, the associated defect made the combination exceptionally rare. Gender assignment and detection of life-threatening conditions (salt-losing crisis due to congenital adrenal hyperplasia or Wilms' tumour) are the main aims when we deal with ambiguous genitalia. The main criteria for the diagnosis of female pseudohermaphrodism are: normal female karyotype 46XX, masculinisation of external genitalia and no palpable gonads. One can reveal urogenital sinus and vagina on genitography, and uterus on ultrasound examination or exploratory laparotomy.5
In our case, there was 46XX female pseudohermaphrodite with normal testosterone and complete masculisation of external genitalia, which is less frequently reported.6
The majority of the patients with posterior cloaca have urinary tract malformations. According to Pena and Kessler, 88% of these patients have urological defects. Hence, urological evaluation to detect these urogenital defects is recommended.3
Surprisingly, there was no urinary tract anomaly on ultrasonography in our patient. The kidneys, ureters and urinary bladder were found normal on sonography and laparotomy.
Further urological evaluation in the form of intravenous urogram, radioisotope renogram and/or MR urogram could not be done because of limited resources and the poverty of the patient. If these investigations would have been done they might have added some additional procedure depending upon the result of tests like nephrectomy for non-functional kidney.
Another associated defect in this patient was congenital rectal stenosis. Congenital rectal stenosis is a rare variant of anorectal malformations. Rectal atresia and rectal stenosis are very rare constituting 1–2% of the anorectal– malformations.7
In this congenital defect, the stenosed rectum is found placed within the levator muscle complex, the anal canal is normal in these patients and no fistula are usually found. The exact embryological mechanism for origin of this anomaly is not known, but it is thought to be secondary to vascular accident during gestational period. Genetic and environmental factors may be implacable according to some researchers.8
The reverse cloaca can be managed in single or multiple stages. Pena and Kessler had managed five patients by staged procedures and four patients in a single stage. They have reported the longest series of posterior cloaca patients' management in English language literature.3
We did diverting transverse colostomy in our patient as her general condition was very poor. The next step is final repair via a posterior sagittal transanorectal approach as described by Pena.3
- Reverse cloaca is an extremely rare entity and it is very hard to find this anomaly in day-to-day clinical practice.
- To diagnose this defect one should be aware of this anomaly and must examine perineum and external genitalia of the patient meticulously.