Department of Paediatric Surgery | Cairo University Specialized Paediatric Hospital (CUSPH) & Cairo University Children's Hospital (CUCH) (email)
Scottish Surgical Paediatric Society
April 2016
Marie Katherine Cox; Mahmoud MA Marei; Fraser D Munro.
Introduction: Suction rectal biopsy is the gold standard investigation for diagnosing Hirschsprung’s disease. There are some technical pitfalls associated with this diagnostic procedure, as well as cost. Simple measures taken at time of biopsy could aid the pathology department in processing and analyzing specimens. Trials analyzing the efficiency of the RBi2 gun show that this method should be sufficient to achieve diagnosis in 93% of patients.
Aims: To describe the quality of suction rectal biopsies taken in the paediatric surgery department, at the Royal Hospital for Sick Children; Regarding (1) Number of specimens taken at biopsy, (2) Whether specimens were labelled according to level above the dentate line, and (3) Whether biopsies were accurate to provide a tissue diagnosis.
Methods: Patients (n=28) who had suction rectal biopsy were indentified over a two-year period (Jan 2014 to Dec 2015) via the databases of the paediatric pathology and paediatric surgery departments (LSA). Pathology reports and operative notes were analyzed for the number of specimens taken at biopsy, labelling according to level above the dentate line, and whether biopsies were sufficient to provide a tissue diagnosis.
Results: An average of 2.5 specimens were taken at biopsy, with 40% of specimens not labelled according to level above the dentate line. 20% of biopsies were insufficient for diagnosis, a significantly higher proportion (p=0.016) compared to the 7% cited in previous trials. The primary reason specimens were insufficient was due to lack of submucosa in the biopsy. Four patients (14%) required repeat biopsy.
Conclusions: The proportion of suction rectal biopsies using the RBi2 gun that were found insufficient for diagnosis was significantly higher than cited in previous studies. Simple measures such as correct labelling and providing three specimens where possible should facilitate processing and analyzing specimens; however, the lack of submucosa in the specimens indicates there is scope for technical improvement in obtaining the biopsy. Manometers for the RBi2 gun have been introduced for surgeons to trial in order to potentially achieve deeper biopsies. Additionally, immunohistochemistry staining, calretinin, may improve diagnostic potential of scanty specimens. Introduction of this stain has been discussed with senior pathologists, and is under consideration owing to this audit.