Congenital malformations of gastrointestinal tract in children aged less than 5 years of age: A retrospective and prospective study

Introduction: The spectrum and prevalence of congenital abnormalities of gastrointestinal tract vary in different populations depending upon the environment influences, genetic predisposition and prevalent socioeconomic factors. The aim of this study is to review and analyse the cases registered in the last five years in our centre and study their clinical presentation, spectrum, prevalence and also the histopathological picture. Methods: This cross-sectional descriptive study was taken up in Niloufer Hospital, Hyderabad. This was a 3 year retrospective and 2 year prospective study. All Pediatric surgical specimens and biopsies of children aged less than 5 years received during a period of 5 years were included in the study. Results: During the study period, total 2842 pathological specimens were reviewed, out of which 161 (5.67%) cases were related to GI tract Anomalies. Hirschsprung’s disease was the commonest accounting for about 47.2% of all the anomalies. Together Hirschsprung’s disease, Omphalo mesenteric duct remnants, intestinal atresia’s, duplication cysts and meconium ileus contributed to greater than 75% (¾ ) of the cases. Most of the cases were less than 1 year of age (71%). Male predominance was noted with a male to female ratio of 2.74:1. Conclusion: Congenital and developmental abnormalities of gastro intestinal tract are not very uncommon in the Indian sub continent and these are a cause of significant mortality and morbidity in pediatric age group. This study has highlighted the prevalence and types of congenital anomalies seen in our Geographical area.


Introduction
Early intrauterine period during 3 rd to 8 th weeks of gestation is the vital period of life for the development of organs and organ systems or organogenesis [1]. Congenital malformations or defects are structural, functional and metabolic disorders at birth and exact causes of birth defects in 40-60% of cases are unknown. However factors like genetic, environmental, teratogenic and infectious agents play important role for the origin of malformations during the most sensitive period of embryogenesis. The spectrum and prevalence of these abnormalities vary in different populations depending upon the environment influences, genetic predisposition and prevalent socioeconomic factors [2]. Except for anecdotal reports no definite study has been done in Indian population to assess the prevalence and spectrum of congenital gastrointestinal tract anomalies in Indian population [3]. Being a tertiary centre, we regularly encounter quite a variety as well as a good number of congenital gastrointestinal abnormalities.
We intend to review and analyse the cases registered in the last five years in our centre and study their clinical presentation, spectrum, prevalence and also the histopathological picture.

Material and Methods
Study Design-This Cross sectional descriptive study was taken up in Niloufer Hospital, Hyderabad. This is a

Research Article
Tropical Journal of Pathology & Microbiology Available online at: www.pathologyreview.in 56 | P a g e 3year retrospective and 2year prospective observational study.
Setting-The present study was done to evaluate the prevalence and pattern of congenital malformations of the gastrointestinal tract based upon the pathological specimen sent. It was taken up in Niloufer Hospital which is a pediatric referral centre for medical and surgical diseases.
Inclusion Criteria-Specimens of children less than 5 years only were included in the study. Quantitative Variables-The various congenital anomalies were analysed and grouped according the age, sex and biopsy sites and further analysis was done.

Participants-
Statistical methods-Data was entered into excel data sheet and appropriate statistical analysis was performed.

Results
From August 2006 to July 2011, the total number of Pediatric surgical specimens and biopsies received at pathology department of Niloufer hospital, Hyderabad for a period of 5 years were 2842.
Out of theses 161 (5.67%) cases were related to congenital and developmental anomalies of gastrointestinal tract in children aged less than 5 years.
Among the GIT anomalies, Hirschsprung's disease was the commonest accounting for about 47.2% of all the anomalies. This was followed by Omphalo mesenteric duct remnants which were accounting for about 13.7% of the cases.
Intestinal atresias were seen in about 8% of the cases and Duplication cysts were responsible for another 6.5% of cases.
Most of the cases diagnosed to have GIT anomalies were less than 1 year of age (71%). The age group ranged from 1 day-5 years with 36% presenting before the age of one month. In the present study, male predominance was noted with a male to female ratio of 2.74: 1.
Among those diagnosed to have Hirschsprung's disease, male predominance was noted with a male to female ratio of 2.8: 1, which was similar to the overall sex ratio.
More than 2/3 of the cases diagnosed were younger than 1 year of age, with around 41% between the ages of 1 month-1 year.

Research Article
Tropical Journal of Pathology & Microbiology Available online at: www.pathologyreview.in 57 | P a g e  (13), the commonest location was Ileal atresia. Most of the cases of omphalomesenteric duct remnants were diagnosed beyond the age of one month (> 90%), with around 45% diagnosed at greater than one year of age. Those who were diagnosed after 1 year of age were exclusively male children. Similar to the patients with Omphalomesenteric duct remnants, enteric duplication cysts were more common in children aged greater than one month of age (70%), with 40% greater than one year of age. Male predominance was also noted in this group except for the patients presenting before age of one month, where female predominance was noted. Ileum {5 (50%)} was the commonest site of enteric duplication cysts followed by gastric and jejunum.  In our study Hirschsprung's disease was the commonest accounting for about 47.2% of all the anomalies, unlike other studies. Probably the Geographical, Ethnic and Genetic differences were the reasons for the differences noted in the distribution of congenital anomalies. In our study more than 2/3 of the cases of Hirschsprung disease diagnosed were younger than 1 year of age, with around 41% of them between the ages of 1 month -1 year. 29% were diagnosed between ages of 1-5 years. Male predominance was noted with a male to female ratio of 2.8: 1. This was similar to the available literature [7,8].

Research Article
Tropical Journal of Pathology & Microbiology Available online at: www.pathologyreview.in 59 | P a g e In Intestinal atresia, the commonest location was Ileum followed by jejunum and colon. In most studies, jejunoileal atresias seem to be more common than duodenal atresias and colonic atresias accounted for least number of cases [9,10,11].
In the present study Omphalomesenteric duct remnants were seen in 13.7% (22 cases) of the patients. Among the omphalomesenteric duct remnants, Meckels diverticulum is the commonest anomaly and in the present study it was seen in 12.47% of the cases (20 cases). Although no sex-based difference was reported in studies that evaluated this condition as an incidental finding during operations or autopsies, males are as much as 3-4 times more prone to complications than females [6].
In the present study compared to the overall group, significant male predominance was noted here (3.4:1). Most of the cases of omphalomesenteric duct remnants in the present study were diagnosed beyond the age of one month (> 90%), with around 45% diagnosed at greater than one year of age.
In the present study Duplication cysts were seen in 6.2% (10 cases). Gastrointestinal duplications are observed in 1 of every 4500 autopsies, predominantly in white males. Oesophago-Gastric Similar to the available literature, Ileum was the most common site of enteric duplication cysts [12,13,14]. Enteric duplication cysts were more common in children aged greater than one month of age (70%), with 40% greater than one year of age. Male predominance was also noted in this group except for the patients presenting before the age of one month, where female predominance was noted.
In the present study Intussusception was seen in 5 cases (3.1%). Its estimated incidence is approximately 1 case per 2000 live births [7]. In the present study the male to female ratio was 1.5:1, In the literature, the male-to-female ratio is approximately 3:1 [7,15,16].
With advancing age, gender difference becomes marked; in patients older than 4 years, the male-to-female ratio is 8:1 [7]. Intussusception is the most common cause of intestinal obstruction in infants between 6 and 36 months of age. Intussusception is less common before three months and after six years of age. Approximately 60% of children are younger than one year of age, and 80% are younger than two years of age [15]. In the present study 80% of the children presenting with Intussusceptions were younger than 1 year of age.

Research Article
Tropical Journal of Pathology & Microbiology Available online at: www.pathologyreview.in 60 | P a g e In the present study, Colorectal polyps were seen in 3 cases corresponding to 1.9% of the patients. All the children who presented with polyps were greater than 2 years of age and all of them were male. In study by Latt TT et al, the mean age of presentation was 5.6 years and about two thirds of the patients were under the age of 5 years [17]. Similar in another study by Prakash mandhan et al the mean age at presentation was 5.2 years, with a male predominance [18]. In the present study, all those diagnosed to have polyps were male. Similarly Prakash mandhan et al and Wajeehuddin et al in their studies also documented a significant male predominance (4:1) [18,19].
Mesenteric cysts are rare; the incidence is about 1 per 140,000 general hospital admissions and about 1 per 20,000 pediatric hospital admissions [20,21]. In a study from Egleston Children's Hospital at Emory University from 1965-1994, showed a prevalence of about 1 case per 11,250 admissions [22]. In the present study mesenteric cysts were seen in 3 cases which contributed for about 1.9% of all cases The age range in present study varied between 0-5 years. In a study by Hebra et al 75% of cases occurred in children younger than 5 years of age [23]. In another study by from Bliss et al approximately one third of cases occur in children younger than 15 years of age [24].
Limitations-As it is a tertiary care hospital or referral centre, prevalence calculated may be higher than the general population in this hospital-based study. Hence, the data cannot be projected to the general population, for which population-based studies are necessary.

Conclusions
Congenital and developmental abnormalities of gastro intestinal tract are not very uncommon in the Indian subcontinent and these are a cause of significant mortality and morbidity in pediatric age group. This study has highlighted the prevalence and types of congenital anomalies seen in our locality. Probably the Geographical, Ethnic and Genetic differences were the reason for the differences noted in the distribution of congenital anomalies.
Though radiodiagnosis is the preliminary diagnostic modality, but gross and histopathologic examination are essential to confirm the diagnosis. Especially in the case of Hirschsprung's disease histopathological examination is the diagnostic modality to ensure early surgical management.
Funding: Nil, Conflict of interest: None initiated, Permission from IRB: Yes