Benign prostatic hyperplasia

22 March 2017 01:35 pm Views - 5505

Throughout the course of human history, the mortality of the human race has declined owing to advancements of medicine and technology. As a result of this increased life expectancy, modern civilization has seen a considerable increase in the ‘ageing population’. Ageing is a process of physical, psychological and social transformation where a person is physiologically unable to meet the demands of the environment over time, basically writing cheques the body cannot cash. Over the course of a person’s lifetime, various health care interventions and medical tweakings are conducted to make the arduous process of ageing as graceful as possible. The elderly face a gradual loss of senses, impaired memory and non-communicable diseases such as high blood pressure, diabetes, heart disease and malignancies, all of which are well-known conditions for which people seek medical help. However there are other health issues that are usually overlooked. Prostatism or Benign Prostate Hyperplasia (BPH) is a very common condition that occurs in old age that may be agonizing but which people are ignorant about. The peak incidence are in men above the age of 40 but symptoms usually appear between the ages of 50-70 years.   

The human excretory system is responsible for ridding the body of waste products and toxins. The kidney acts as the principle organ of the excretory system that filters the blood, constantly clearing unwanted waste materials that are either ingested or produced in the body, thus producing urine. In addition, the kidneys aid in the regulation of the volume and composition of fluids and virtually keeping all the electrolytes in the body at optimal concentrations. The waste products include urea, creatinine and other metabolites resulting from breakdown of various compounds in the body.  

 
The excretory system comprises of a pair of kidneys, two ureters, a bladder and urethra. The urine is propelled through each ureter of the respective kidney which finally fill up the bladder. The bladder serves as a muscular reservoir for urine that has the ability to stretch when it is being filled.

Specialized receptors (sensors) are located in the bladder wall that are sensitive to stretch. The bladder is progressively filled with urine, building up a tension within its walls. When the tension exceeds a certain threshold, the receptors alert the nervous system via the nerves that innervate the bladder. This alert triggers a reflex mediated by the nervous system that signals the bladder and its sphincter, thus eliciting “nature’s call”. Although this is a reflex, our brain has voluntary control over the urge to urinate. Once the urination is initiated, the bladder musculature contracts, thereupon propelling urine through the bladder neck that funnels into the urethra. The male and female excretory systems are identical with the exception of the urethra, as the male urethra serves as a common tube for the passage of urine to the exterior and semen during ejaculation serving a dual functionality of excretory and reproductive systems. The male urethra is longer than that of the female, with 4 distinctive parts extending from the bladder neck to the tip of glans penis (external urethral meatus) namely the prostatic, membranous, bulbar and penile urethra.   

The prostate is a muscular gland that serves as part of the male reproductive system. It encircles the bladder neck and the proximal part of the urethra, hence the name “prostatic urethra”. It is a wedge shaped gland approximately 20g in weight and 3cm in length. The prostate is responsible for secreting 30% of the fluid in semen that is slightly alkaline in nature that protects and nourishes the sperm. The growth of the prostate gland is under hormonal control by testicular androgens (male sex hormones). Testosterone is the principle testicular androgen that controls the growth and survival of prostatic cells. The prostate possesses an enzyme (5-alpha reductase) that converts testosterone into dihydrotestosterone (DHT), a more potent form.  

In benign prostatic hyperplasia, due to an unclear cause, DHT increases prostatic cellular growth and inhibits cell death that leads to accumulations of senescent prostatic cells causing the gland to enlarge, a natural phenomenon of ageing in a majority of men.It is important to know that it is not malignant (cancer) or a premalignant lesion (giving rise to cancer) although an enlarged prostate provokes suspicion of prostatic cancer.  

 

Symptoms  
In BPH, the enlarged gland compresses the urethra, hence obscuring the urinary flow through that kindles symptoms of this condition. (It gives rise to a spectrum of symptoms that stems from increased size of the prostate and prostatic contractions). A spectrum of symptoms arise depending on the degree of obstruction ranging from no symptoms to lower urinary tract symptoms, bladder outflow obstruction to urinary retention giving rise to various complications. The obstruction to urinary flow through the urethra causes the following lower urinary tract symptoms or LUTS.  

 

• Hesitancy (Difficulty to initiate urination that is not relieved by straining)  
• Poor stream  
• Intermittent flow of urine  
• Dribbling (appearance of few drops continuously following the cessation of the main stream)  
• Incomplete evacuation of the bladder that causes retention of urine within the bladder triggering the stretch receptors of the bladder with a smaller volume of additional urine, causing,  
• increased frequency of urination including at night  
• Urgency (Urgent need to pass urine once the desire arises)  

Due to the increased workload resulting from the resistance to urinary flow, the bladder increases in muscle mass and distends further, precipitating the retention of urine within the bladder. With chronic retention, the residual urine serves as a reservoir for infection and formation of stones. Recurrent urinary tract infections are usually a “wake-up call”.  

 

• Blood in urine (due to rupture of blood vessels)   

Complications are urinary retention, recurrent urinary tract infections, urinary stones and kidney failure in the extreme cases. Acute retention presents an emergency with severe pain that is a mere exaggeration of the normal desire to urinate and requires urgent catheterization to alleviate symptoms.  

 

Diagnosis  
A thorough history and examination helps the clinician arrive at a probable diagnosis. Abdominal examination may reveal a distended bladder with chronic retention. Features of anaemia and dehydration may be present with chronic kidney impairment. The external urethral meatus and the testicles are examined to exclude other causes. A digital rectal examination assists in suspicion of prostatic cancer. Neurological examination excludes lesions in the nervous system with diabetes, Parkinson’s disease and other neurological lesionsthat may have given rise to the retention of urine.  

 

Investigations   
Imaging methods such as abdominal, pelvis and trans-rectal (through the rectum) ultrasound scan to detect prostate enlargement, residual urine volume in the bladder, and assess complications such as hydronephrosis (swollen kidneys) and bladder trabeculae (pouches formed in the bladder wall). If prostatectomy surgery is decided, a cystourethroscopy is done to inspect the urethra to determine the route of surgery (Whether through the urethra or open surgery)   

In addition, lowered haemoglobin content in full blood count, high serum creatinine levels and abnormal serum electrolyte concentrations arise suspicion of renal impairment. A full urine report and culture is used in the case of infection while prostate antigen testing and biopsy is performed when there is suspected prostate cancer. Uro-flowmetry is not routinely performed in Sri Lanka.  

 

Management  
The management strategies depend upon the severity of symptoms and the presentation. Some BPH don’t always require treatment but it is recommended to arrange regular appointments with your doctor to monitor your symptoms and the size of your prostate. Conservative measures, medical and surgical therapy is currently available as treatment of BPH. Conservative management is followed in men with mild symptoms, fair urine flow rate and satisfactory bladder emptying as well as in men who aren’t fit for surgery due to age or other medical problems.  

These measures include,  

•  urination without postponing once the urge arises  
• be careful with drugs such as anti-muscarinics as they may precipitate the symptoms  
•  Limit fluid intake  
•  limit alcohol and caffeine ingestion  

It is important to adhere to the prescription of a medical professional, as the treatment for each patient is tailored to fit his symptoms (graded by IPSS score and uro-flowmetry) and physical state. These medical therapies include ‘alpha-1 adrenergic blockers’ that ease the urinary flow by inhibiting the contraction of the muscle fibres of the prostate and ‘5-alpha reductase inhibitors’ that decreases the size of the prostate and is mandatory to check response to treatment. Surgery is indicated in patients with severe symptoms, episodes of acute and chronic retention, renal impairment, complications and those who do not respond to medical therapy. The surgical methods available are TURP (Transurethral resection of the prostate) and open surgery.  

It is important to discuss the outcomes and complications of prostatectomy with the surgeon before complying with the treatment. The bottom line is to age gracefully and get yourself checked for even the lesser-known overlooked demons like BPH.