Fowler’s syndrome
Clinically Relevant Anatomy
The normal control of urine undergo a complex network between signals from the brain and lower urinary tract to work together. When the bladder fills about 300–400 mL, it starts to send signals to the sacral spinal cord, that sends afferent signals to a brain area called the periaqueductal gray (PAG), where integration of afferent information from the lower urinary tract system via the sacral cord with information from frontal networks (the precentral gyrus, anterior cingulate gyrus and limbic system). So, if the environment is socially safe to urinate (like in a bathroom), the PAG activate the inhibition of the pontine micturition center (PMC) to activate urination, on the other side if there is negative feedback (like pain, anxiety, or fear, unsuitable situation), the PAG will keep the inhibition of the urination reflex.
With abnormal activity of external urethral sphincter (overactivity), in its turn sends inhibitory signals back to the sacral spinal cord as a result, the afferent signals to the brain (PAG) does not get the message that the bladder is full and in turn the patient will not feel the urge to urinate, leading to urinary retention.
Introduction
Fowler’s Syndrome (FS) defined as inability to pass urine normally first described in 1985, it is uncommon clinical diagnosis and one of the causes of chronic urinary retention in absence of any other pathology with incidence rate of 0.2 cases per 100,000 per year, and usually characterized by a large bladder capacity, reduced sensation, increased maximal urethral closure pressure and impaired urethral relaxation, and detrusor underactivity.
Fowler’s syndrome was found in post-menarche young women in their second and third decades of life, and was found on teenage. There was a common factor was noted across the cases, most of the patients present a trigger medical event in their medical history, such as gynecological surgery or other surgical procedures (laparoscopic appendectomy, urethral dilatation, urethrotomy, hysterectomy, or myomectomy,)[1], childbirth, and acute medical conditions. Poly cystic ovarian syndrome, endometriosis, subfertility were observed in women with urinary retention and this was explained as something that might just be happening by chance, not because one causes the other.
Mechanism of Injury / Pathological Process
There is no definite cause or explanations of how or why this conditions happen and still unclear but there are hypothesizes that explain the condition[2]:
Primary hyperactivity of the external urethral sphincter and failure of relaxation of the urethral striated muscles, resulting in an increase in urethral afferent activity, inhibiting the bladder afferent signals to the brain. This hyperactivity can be detected and diagnosed by EMG.
Hormonal changes that may happen with conditions like Polycystic Ovary Syndrome (PCOS), may cause abnormal electrical signal transmission through the muscle membrane.
Clinical Presentation
- Reduced sensation of bladder fullness
- Reduced urinary frequency
- Prolonged micturition time.
- Voiding dysfunction (weak micturition stream/ interrupted, sensation of incomplete bladder emptying).
- Painless retention with a large residual volume of urine (> 1000 mL)[2].[1]
- High rates of bladder, urethral and pelvic pain[3]
- No history of urological abnormalities in childhood or associated abnormalities of the urinary tract
Diagnostic Procedures
Concentric needle electromyography (EMG) is the gold standard for diagnosis. It shows complex repetitive discharges (CRDs) in which the electrical signals are unlike that normal signals which originate from neuromuscular transmission, it was noted to be transmitted from adjacent membranes in parallel waves, though there is a continuous excitatory activity of external urethral sphincter and failed to relaxation[4]. On the other side the abnormal signal activity of EMG was found in about 30–53% of healthy, asymptomatic women.
Functional magnetic resonance imaging (fMRI), there was a negative response and a decrease in the activity of brain areas in response to bladder filling in women with FS compared to healthy women[5].
Urodynamic, will show large bladder capacity, reduced sensation, an increase in maximal urethral closure pressure (MUCP), and detrusor underactivity matching with the symptoms and characteristics of FS.
Management / Interventions
Sacral neuromodulation (SNM)
It restore the balance in signals between spinal cord and higher centers. It is a permanent electrical stimulation of sacral nerve roots through an implantation of S3 neurostimulators[1][2], however this direct, continuous effect of sacral nerves help patients with urination it still has no effect on overactivity of eternal urethral sphincter. SNM considered the only treatment intervention available for this condition after self catheterization.
Differential Diagnosis
Urethral obstruction
Neurogenic bladder
Medication-Induced Retention[2] (opiates, drugs with anticholinergic activity)[6]
Detrusor underactivity
Radical pelvic surgery
Resources
References
- ↑ 1.0 1.1 1.2 Trachta J, Wachter J, Kriz J. Chronic Urinary Retention due to Fowler's Syndrome. European Journal of Pediatric Surgery Reports. 2018 Jan;6(01):e77-80.
- ↑ 2.0 2.1 2.2 2.3 Szymański JK, Słabuszewska-Jóźwiak A, Jakiel G. Fowler’s syndrome—the cause of urinary retention in young women, often forgotten, but significant and challenging to treat. International Journal of Environmental Research and Public Health. 2021 Mar 23;18(6):3310.
- ↑ Cox ER, Panicker JN, Coombe D, Selai C, Ellis D, Stone J, Hoeritzauer I. Fowler’s syndrome—Patient led phenotyping of 265 patients. Continence. 2024 Dec 1;12:101710.
- ↑ Osman NI, Chapple CR. Fowler's syndrome—a cause of unexplained urinary retention in young women?. Nature Reviews Urology. 2014 Feb;11(2):87-98.
- ↑ Kavia R., Dasgupta R., Critchley H., Fowler C., Griffiths D. A functional magnetic resonance imaging study of the effect of sacral neuromodulation on brain responses in women with Fowler’s syndrome. BJU Int. 2010;105:366–372. doi: 10.1111/j.1464-410X.2009.08819.x
- ↑ Panicker JN, Pakzad M, Fowler CJ. Fowler's syndrome: a primary disorder of urethral sphincter relaxation. The Obstetrician and Gynaecologist. 2018;20(2):95-100.