Giant Urinary Bladder in a Woman with Down Syndrome: A Case Report

Introduction

Chronic urinary retention is characterized by the ongoing inability to fully empty the bladder, despite the ability to urinate [1]. Non-neurogenic neurogenic bladder (NNB) is a functional cause of chronic urinary retention and refers to the intermittent and/or fluctuating flow rate caused by involuntary contractions of the external sphincters during voiding in individuals with normal neurological function [2]. NNB is characterized by the inability to suppress the detrusor contraction reflex and an over-active external sphincter [3]. In normal bladder filling, there is low bladder pressure and a closed bladder outlet [4]. This is followed by normal bladder emptying, which requires coordinated contraction of the bladder muscle and relaxation of the external urethral sphincter [4]. Regulation of this micturition reflex involves parasympathetic, somatic, and sympathetic innervation. However, individuals with NNB experience forceful contractions of the voluntary external sphincters during voiding, obstructing the bladder outlet [4]. Contributing factors can include excessive pelvic floor muscle training, emotional factors, trauma related to toilet training, and psychiatric disorders [5–7].

A retrospective analysis of 26 female patients diagnosed with NNB revealed that 19% of the patients had chronic urinary retention. The most common symptoms described were urgency and frequency, which occurred in 82% of the cases [8]. A persistent urinary retention typically involves a volume exceeding 800 mL and typically ranges from 1.0 to 1.5 L of retained urine, with certain instances reporting volumes surpassing 4 L [9]. The enlarged bladder can exert pressure on neighboring structures because of the limited space within the pelvis [10].

The diagnostic challenge of distinguishing between massive urinary bladder distension and ovarian tumors from clinical presentation alone remains a relatively unexplored area in medical literature. Existing literature offers limited insight into cases in which a massively distended urinary bladder mimics an ovarian tumor. While various pathologies, such as those involving the uterus, fallopian tubes, gastrointestinal tract, or mesentery, have been reported to mimic ovarian tumors, instances of the urinary bladder posing as such are notably absent from existing reports [11–13]. Noteworthy among reported cases are those of giant hydronephrosis [11].

Here, we report a case of a giant urinary bladder presenting with symptoms and signs mimicking an ovarian tumor in a female patient with Down syndrome.

Case Report

A 31-year-old woman with Down syndrome was referred by the primary care physician to the Emergency Department (ED) for weight loss of 5 kg over 1 month and loss of appetite of a 2 weeks’ duration. Her mother also noted a gradually increasing abdominal distension over a 3-year period.

Prior to this presentation, the patient had been well. She had no significant past medical history and was not on any prescribed or over-the-counter medications. She was fully independent in her activities of daily living. She worked as a helper at a rehabilitation center, alongside her mother. She had never indicated any symptoms of urinary tract infection, constipation, or abdominal pain. Her menses were also regular, with no menorrhagia, dysmenorrhea, or intermenstrual bleed. She was not sexually active.

Upon presentation at the ED, she appeared dehydrated and lethargic. However, she was afebrile, and all her vital signs were normal. Her blood pressure was 104/60 mmHg, pulse rate was 69 beats per min, and oxygen saturation was 99% on room air. Down syndrome features of a flat facial profile, upward slanting eyes, and a small nose were apparent. She had limited verbal communication, which was the same since she was a child.

On palpation of the abdomen, it was soft and non-tender. A palpable mass was identified rising from the lower abdomen, measuring approximately 24 weeks in size, resembling a gravid uterus. The mass was firm, non-mobile, and non-tender. Systematic neurological examination and external genitalia examination revealed normal findings. Transabdominal ultrasound revealed a normal uterus with a normal endometrial thickness but identified a large, uniloculated cystic lesion measuring 11×15 cm, with no solid areas or papillary projections. The urinary bladder was not identified, suspected to be hidden below the large cystic lesion, which appeared to be ovarian in origin.

A urine pregnancy test returned negative. Initial renal profile was deranged, with urea level of 6.9 mmol/L and creatinine level of 137 mmol/L, which rose to urea of 7.8 mmol/L and creatinine of 156 mmol/L, despite the administration of intravenous hydration. This, in addition to the presentation of significant weight loss and abdominal distension, increased the suspicion that the mass was malignant in nature. Full blood count, liver function test, and electrolyte results were within the normal ranges, while urinalysis yielded normal findings.

Tumor markers were sent, and a computed tomography scan of the abdomen and pelvis was arranged. Alpha fetoprotein, cancer antigen (CA) 125, CA 19-9, and carcinoembryonic antigen results were within normal ranges. Meanwhile, the computed tomography scan unveiled a huge pelvic cystic mass, likely representing a massively distended urinary bladder, measuring 11.6×13.6×17.6 cm and causing bilateral obstructive uropathy with moderate hydronephrosis and hydroureter (Figures 1–4). Both the ovaries were able to be visualized and were of normal parameters.

On further history, the patient’s mother reported that in the past few years, the patient needed frequent prompting to pass urine, although she never indicated if she had any problems with her urinary function. A urinary catheter was subsequently inserted, which drained 1900 mL of urine, and her abdominal distension significantly improved. The renal function also picked up to a urea of level of 5 mmol/L and creatinine level of 103 mmol/L.

Due to the patient’s limited verbal communication and significant discomfort with urinary catheterization, the urologist could not proceed with a urodynamic study or voiding cystourethrography. However, based on the patient’s history and examination, external anatomical obstruction or a neurological abnormality contributing to patient’s urinary retention were excluded. The patient was discharged home with intermittent self-catheterization. She presented again 1 month later at the ED with a full bladder, although not a huge one this time. On discharge from the ED, the patient and mother were taught trial of void and behavioral modifications to help regulate her passing urine. The patient was able to perform timed voiding and regulate her fluid intake at home successfully. Six months after discharge, the patient had been able to pass urine as normal without needing a catheter and had no further occurrence of urinary retention to date. Based on this, a diagnosis of functional voiding dysfunction or non-neurogenic neurogenic bladder was given.

Discussion

This case highlights the challenges in accurately diagnosing adnexal masses solely through clinical assessment and basic imaging, given the complex pelvic anatomy. Both ovarian and extra-ovarian pathologies can mimic ovarian malignancy, with 5.1% of initially suspected ovarian cancers turning out to be extra-ovarian diseases [13]. Given the overlap in clinical symptoms between malignant and non-malignant conditions, advanced imaging is crucial for accurate diagnosis [13]. Thus far, a case of giant urinary bladder mimicking an ovarian tumor has not been reported.

Giant urinary bladder is an uncommon, progressive condition usually caused by prostatic enlargement or neurological dysfunction [10]. Chronic urinary retention usually presents with a volume of greater than 1 to 1.5 L of retained urine [10]. Giant urinary bladder has not been well defined in terms of bladder volume or other variables [14]. The handful of cases reported have been mostly below 5 L, of which the latest reported volume is 11 L [10]. The causes of previous reported cases of giant urinary bladder include inferior vena cava obstruction, diabetic neuropathy, and bladder neck obstruction [10,15–17]. Other reported cases, which presented together with large hydronephroses, were also induced by anatomical restriction [11,16]. As of now, there have been no meta-analyses or systematic reviews published regarding the prevalence of giant urinary bladder, indicating its rarity.

Down syndrome is linked to various genitourinary issues. A systematic review by Mercer et al found common abnormalities, including renal hypoplasia, obstructive uropathy, and glomerular microcysts, along with developmental anomalies, such as megaureter and vesicoureteral reflux [18]. Bladder dysfunction is classified into neurogenic, anatomic, and functional causes [19]. Neurogenic causes encompass central nervous system damage, while anatomic causes include urinary outlet blockage [19]. The most severe type of bladder dysfunction is NNB, which is characterized by functional dysfunction without neurological problems [3].

Handel et al and Hicks et al were amongst the first to identify NNB in association with Down syndrome, discovering a higher incidence of NNB than other urological abnormalities in Down syndrome [2,20]. This is supported by recent studies that highlighted a concerning increase in functional voiding problems amongst individuals with Down syndrome [2,4,21,22]. Notably, patients with Down syndrome commonly exhibit urinary holding maneuvers and straining behaviors [2]. Furthermore, the study by Kitamura et al revealed that children with Down syndrome often experience lower urinary tract symptoms, abnormal uroflow findings, and significant post-void residual, even in the absence of urinary tract anomalies, severe constipation, or mental health issues [22]. This suggests that many urinary issues in patients with Down syndrome stem from functional disturbances within the bladder or micturition center, rather than from structural abnormalities or other comorbidities.

The mechanism of dysfunctional bladder in Down syndrome remains unclear. An unpublished article by Agni Vlahos from Advocate Lutheran General Hospital suggests that individuals with Down syndrome may have reduced muscle tone, leading to less firmness and relaxation of bladder muscles when not in use. This can hinder effective contraction during urination, causing difficulties in initiating the urine stream or retaining urine after voiding. Furthermore, delaying urination for prolonged periods can weaken the bladder over time, exacerbating these issues.

Diagnosing NNB requires ruling out anatomical or neurogenic causes through thorough investigation. Diagnostic measures can include blood tests, assessment of post-voiding residual, and various imaging modalities [23]. Conservative management, such as timed voiding and lifestyle adjustments, is typically the first-line treatment [23]. Medical interventions, such as anticholinergics, can be considered, with regular monitoring to assess treatment efficacy [23]. Intermittent catheterization or surgical interventions can be necessary in severe cases [23]. In this case, behavioral modification successfully resolved the urinary retention, a common approach for functional voiding dysfunction or NNB, when further diagnostic procedures are not feasible.

The massive urinary bladder distension observed in this case led to bilateral obstructive uropathy, resulting in the acute impairment of renal function. The distended bladder compressed the ureters, obstructing the normal flow of urine from the kidneys to the bladder. This obstruction caused a backup of urine into the kidneys, leading to hydronephrosis and subsequent renal dysfunction. As the bladder distension resolved, there was resolution of the kidney function.

To prevent further recurrence, the patient’s caregiver was advised to be more vigilant in monitoring the urinary practices of the patient, reminding the patient not to withhold her urine and to inform the caregiver if she had any other new problems that could affect her passing urine.

This case underscores the importance of vigilance and proactive management in preventing complications associated with urinary dysfunction in individuals with developmental disabilities. Early recognition of symptoms, regular monitoring, and prompt referral to specialists are essential components of clinical practice to prevent adverse outcomes related to urinary tract abnormalities.

Conclusions

This case report highlights the need for thorough evaluation and use of advanced imaging techniques in diagnosing adnexal masses, especially in differentiating between ovarian and extra-ovarian conditions. Routine imaging studies, such as ultrasound, can help identify urinary tract abnormalities before they progress to significant complications. Furthermore, it sheds light on the spectrum of genitourinary issues in patients with Down syndrome that physicians need to be aware of in order to treat these patients. Educating caregivers and healthcare providers about the signs and symptoms of urinary dysfunction in individuals with developmental disabilities can facilitate early detection and intervention. The successful management of the patient’s bladder dysfunction through individualized care and ongoing monitoring demonstrates the potential for effective intervention and improved quality of life in individuals with Down syndrome who face similar issues of functional voiding dysfunction. Encouraging timely referrals to specialists, such as urologists, for further evaluation and management of urinary tract abnormalities, can prevent the development of complications, like obstructive uropathy and renal dysfunction.