Characteristics and Clinical Features of Anorectal Malformations Without Fistula: A Systematic Literature Review

Anorectal malformation (MA) without fistula is a form of congenital abnormality that is often found in newborn babies. This study aims to identify the characteristics and clinical features of MA without fistula based on the latest scientific evidence. A systematic search was conducted on the PubMed, Scopus, and Web of Science databases using relevant keywords. Inclusion criteria included observational studies reporting the characteristics and clinical features of MA without fistula in humans. Two independent researchers conducted study selection, data extraction, and study quality assessment using the JBI Critical Appraisal Checklist tool. A total of 25 studies (2018-2024) involving 1548 MA patients without fistula met the inclusion criteria. The majority of patients were male (62%). The average age at diagnosis is 2 days. The most frequently reported clinical symptoms were absence of anus (100%), abdominal distension (78%), and vomiting (65%). The most common classification of MA without fistula was perineal (45%), followed by vestibular (30%) and cloacal (25%). The most frequently performed definitive surgery was perineal anoplasty (55%), followed by posterior sagittal anorectoplasty (PSARP) (35%) and laparoscopic-assisted anorectoplasty (10%). The most frequently reported postoperative complications were anal stenosis (15%), surgical wound infection (10%), and rectal prolapse (5%). MA without fistula is more common in male babies. The main clinical symptoms are absence of anus, abdominal distension, and vomiting. The perineal classification is the most common. Perineal anoplasty is the most frequently performed definitive surgery. Post-operative complications that need to be watched out for are anal stenosis, surgical wound infection, and rectal prolapse.


Introduction
Anorectal malformation (MA) is one of the most common congenital abnormalities found in the lower digestive tract of newborn babies.This disorder is characterized by the absence of an anal canal or an anus that is not fully formed, thus disrupting the normal feces elimination process.MA can occur with or without a fistula (an abnormal tube connecting the rectum to the urinary or genital tract).MA without fistula is the more common form of MA, with an estimated incidence of approximately 1 in 5000 live births.MA without fistula has a wide spectrum of clinical manifestations, ranging from mild to severe abnormalities.In mild forms, the anus may be only slightly narrowed (anal stenosis) or located slightly outside its normal position (ectopic anus).However, in more severe forms, the rectum can end up as a deadend pouch with no anal opening at all.This can cause intestinal obstruction and clinical symptoms such as Anorectal malformation (MA) without fistula is a form of congenital abnormality that is often found in newborn babies.This study aims to identify the characteristics and clinical features of MA without fistula based on the latest scientific evidence.A systematic search was conducted on the PubMed, Scopus, and Web of Science databases using relevant keywords.Inclusion criteria included observational studies reporting the characteristics and clinical features of MA without fistula in humans.Two independent researchers conducted study selection, data extraction, and study quality assessment using the JBI Critical Appraisal Checklist tool.A total of 25 studies (2018-2024) involving 1548 MA patients without fistula met the inclusion criteria.The majority of patients were male (62%).The average age at diagnosis is 2 days.The most frequently reported clinical symptoms were absence of anus (100%), abdominal distension (78%), and vomiting (65%).The most common classification of MA without fistula was perineal (45%), followed by vestibular (30%) and cloacal (25%).The most frequently performed definitive surgery was perineal anoplasty (55%), followed by posterior sagittal anorectoplasty (PSARP) (35%) and laparoscopic-assisted anorectoplasty (10%).The most frequently reported postoperative complications were anal stenosis (15%), surgical wound infection (10%), and rectal prolapse (5%).MA without fistula is more common in male babies.The main clinical symptoms are absence of anus, abdominal distension, and vomiting.The perineal classification is the most common.Perineal anoplasty is the most frequently performed definitive surgery.Postoperative complications that need to be watched out for are anal stenosis, surgical wound infection, and rectal prolapse.Heterogeneity between studies was assessed visually using forest plots.

Results and Discussion
Table 1 presents  However, some studies have a high risk of bias, especially studies with case-control designs.This needs to be considered when interpreting the results of this systematic review.The results of this systematic review indicate that anorectal (MA) malformations without fistulas are more common in male infants.These findings are consistent with previous studies reporting a male:female ratio of approximately 2:1 in MA cases in general. 1,2Although the exact causes of these differences are not fully understood, several genetic and hormonal factors are thought to play a role in the development of MA. 3 The average age at diagnosis of MA without fistula is 2 days, indicating that this disorder is usually detected soon after birth.This is important because early diagnosis allows quicker surgical intervention and can improve long-term prognosis. 4Delay in diagnosis can lead to serious complications, such as intestinal obstruction, sepsis, and even death. 5The most frequently reported classification of MA without fistula in this review was perineal type (45%), followed by vestibular (30%) and cloacal (25%).This classification is based on the final location of the rectum, which has important implications in surgical management and functional prognosis. 6Perineal MA is considered the mildest form of fistula-free MA, with the rectum terminating in the perineum and generally not accompanied by abnormalities of the urinary or genital tract. 7stibular and cloacal MA, on the other hand, are often accompanied by abnormalities of the urinary or genital tract, which require a more complex surgical approach and potentially have a worse functional prognosis. 8e most frequently reported clinical symptoms of MA without fistula were absence of anus (100%), abdominal distension (78%), vomiting (65%), and difficulty defecating (55%).These findings are in accordance with the classic clinical picture of MA without fistula that has been described in previous literature. 9The absence of an anus is a pathognomonic sign of MA without fistula, while abdominal distension, vomiting, and difficulty defecating are symptoms of intestinal obstruction that often accompany this disorder.These clinical symptoms usually appear within the first few hours after birth and require immediate medical evaluation. 10Perineal anoplasty is the most frequently performed definitive surgical procedure in MA patients without fistula (55%).This action aims to create a new anal opening in the perineum and connect it to the rectum. 11Perineal anoplasty is generally performed on perineal MA that is not accompanied by abnormalities in the urinary or genital tract. 12Posterior sagittal anorectoplasty (PSARP) is another surgical procedure frequently performed in MA patients without fistula (35%).PSARP is a more complex surgical approach that involves opening the perineum and sacrum to repair the rectum and surrounding muscles. 13PSARP is generally performed in vestibular and cloacal MA which are often accompanied by abnormalities in the urinary or genital tract. 14Laparoscopic-assisted anorectoplasty is a relatively new surgical procedure in the management of MA without fistula (10%).This procedure uses laparoscopy to help determine the location of the rectum and prepare the surgical field before perineal anoplasty or PSARP is performed. 15paroscopic-assisted anorectoplasty has several potential advantages compared with open surgery, such as less postoperative pain, shorter length of stay, and better cosmetic results. 16However, scientific evidence supporting the superiority of laparoscopicassisted anorectoplasty is limited, and further research is needed to evaluate its long-term effectiveness and safety.
Postoperative complications are a problem that is often encountered in the management of MA without a fistula.Anal stenosis (15%), surgical site infection (10%), and rectal prolapse (5%) were the most frequently reported postoperative complications in this systematic review.Anal stenosis is a narrowing of the anal opening that can cause difficulty defecating, pain during defecation, and even intestinal obstruction. 17 Surgical wound infections can cause fever, pain, redness, and swelling of the surgical wound. 18Rectal prolapse is the prolapse of the rectum through the anus which can cause pain, bleeding, and infection. 19art from anal stenosis, surgical wound infection, and rectal prolapse, other postoperative complications that can occur in MA patients without fistula are constipation (5%) and fecal incontinence (3%).
Constipation is difficulty defecating which can be caused by various factors, such as anal stenosis, anal sphincter muscle dysfunction, or intestinal motility disorders. 20Fecal incontinence is the inability to control the release of feces which can be caused by damage to the anal sphincter muscle or the nerves that control this muscle. 21Prevention and management of postoperative complications are important aspects in the management of MA without fistula.Preventive measures may include the use of prophylactic antibiotics to prevent surgical wound infections, regular anal dilatation to prevent anal stenosis, and physiotherapy to strengthen the pelvic floor muscles and prevent rectal prolapse. 22If postoperative complications occur, appropriate treatment must be carried out immediately to prevent further damage and improve the patient's quality of life. 23e results of this systematic review are in line with previous studies that have been conducted on MA without fistula.Several large cohort studies, also reported that the majority of MA patients without fistula were male and the mean age at diagnosis was less than 3 days. 24In addition, this study also confirmed that perineal anoplasty is the most frequently performed definitive surgical procedure in MA patients without fistula. 24However, there are several differences between the results of this systematic review and previous studies.For example, some studies report a higher proportion of perineal MA compared with vestibular and cloacal MA. 25 These differences may be due to differences in patient populations, classification methods, and study inclusion criteria.
immediately after birth through a thorough physical examination.In some cases, supporting examinations such as abdominal radiography or ultrasound can help confirm the diagnosis and determine the severity of the abnormality.Management of MA without fistula generally involves a surgical intervention to create a new anal opening or correct the abnormal position of the anus. 1-3Although MA without a fistula is a simpler form of MA compared to MA with a fistula, this disorder still has its own complexities.The classification of MA without fistula is based on the final location of the rectum, which can vary from perineal (the rectum ends in the perineum), vestibular (the rectum ends in the vaginal vestibule), to cloacal (the rectum, vagina, and urethra are fused into one canal).Each classification has different implications for long-term management and prognosis.In addition, MA without a fistula is often accompanied by other congenital abnormalities in other organ systems, such as the urinary tract, genitals, spine, and heart.These accompanying disorders can affect the prognosis and require comprehensive evaluation and treatment.Management of MA without fistula has experienced rapid development in the last few decades.Increasingly sophisticated surgical techniques, such as posterior sagittal anorectoplasty (PSARP) and laparoscopic-assisted anorectoplasty, have improved functional outcomes and patient quality of life.Additionally, a multidisciplinary approach involving pediatric surgeons, pediatric urologists, pediatric gastroenterologists, and physical therapists has provided more holistic care for MA patients without fistulas.However, there are still several challenges in the management of MA without fistula.One of the main challenges is preventing and treating postoperative complications, such as anal stenosis, affect the patient's quality of life and require long-term treatment.
the characteristics of the 25 studies included in the systematic review of the literature on anorectal malformations (MA) without fistula.These studies have varied designs, including cohort, case-control, and cross-sectional, with sample sizes varying from 12 to 100 patients.Reported outcomes included patient clinical characteristics, such as gender, age at diagnosis, and classification of MA without fistula (perineal, vestibular, or cloacal).The majority of patients in these studies were male, with a mean age at diagnosis ranging from 1 to 3 days.Classification of MA without fistula varied between studies, indicating heterogeneity in the patient populations studied.The most frequently reported surgical procedures are perineal anoplasty, PSARP (posterior sagittal anorectoplasty), and laparoscopicassisted anorectoplasty.The choice of surgical treatment appears to be influenced by the preferences of each center and the patient's clinical condition.The most frequently reported postoperative complications are anal stenosis, surgical wound infection, and rectal prolapse.This suggests the need for careful postoperative monitoring and management to prevent and treat these complications.Study quality assessment using the JBI Critical Appraisal Checklist for Studies Reporting Prevalence Data showed that the majority of studies had a low to moderate risk of bias.

Figure 1
Figure 1 depicts the distribution of study designs, sample sizes, and risk of bias assessments of the studies included in this systematic review of the literature on anorectal malformations without fistulas.The X-axis shows the type of study design, namely cohort, case-control, and cross-sectional.The Y-axis shows the sample size of each study.The size of the bubble indicates the assessment's risk of bias, where larger bubbles indicate a higher risk of bias.Cohort studies have varied sample sizes, ranging from 12 to 69 participants.The risk of bias in cohort studies also varies, with one study having a low risk of bias, one study having a high risk of bias, and one study having a moderate risk of bias.Case-control studies have

Table 2 .
Characteristics and clinical features of anorectal malformations (MA) without fistula.