Bladder Agenesis: A Systematic Review

Bladder agenesis is a rare congenital deformity characterized by the absence of the bladder. It is primarily observed in postmortem dissections of stillbirths rather than live births. The condition is often associated with other congenital anomalies, leading to the hypothesis that most affected fetuses do not survive to term. However, the exact cause and specific associated anomalies remain unclear and poorly described in the literature. The limited mention of bladder agenesis in textbooks and literature underscores the importance of creating a comprehensive source for future research in this field. Therefore, our objective is to collect and analyze data on bladder agenesis, focusing on associated anomalies and potential causes, to enhance our understanding of the condition. We conducted a thorough review of reports collected from three databases, Google Scholar, PubMed, and Science Direct, last searched on July 30, 2023, starting with 327 reports. Excluding duplicates and records written in languages other than English, veterinary studies, irrelevant reports, or stillbirths. Inclusion criteria were the following: cases must have proven bladder agenesis, not hypoplasia, and must have most of the information, including the age of diagnosis, presenting symptoms, gender, associated anomalies, and management or outcome of the patient. A quality assessment was conducted according to the Joanna Briggs Institute checklist for case reports. A total of 65 case reports from 56 articles were included in the review. Through our manual analysis, we documented a wild array of malformations associated with bladder agenesis. Among the reports reviewed, 93% exhibited urinary system malformations beside bladder agenesis, 77% were found to have reproductive malformations, 44% had gastrointestinal anomalies, 38% showed musculoskeletal malformations, 28% had cardiac malformations, and another 28% had vascular anomalies. The overall mortality rate was 38%, with a higher rate of 74% for males compared to 20% for females. By collating and analyzing those case reports, we aim to contribute to a better understanding of bladder agenesis and its associated anomalies, facilitating further investigations and advancements in the field.