Symptoms, Signs and Investigation of Urinary Tract Disorders

Pain Arising From the Kidneys and Upper Tract

Both renal inflammation and stretching of the renal capsule cause pain in the renal angle, the posterior gap between the lowest rib and iliac crest. This area may also become tender to palpation or percussion. Renal stones, tumours or polycystic disease may cause dull and persistent loin pain even without obstruction.

In acute infections, such as pyelonephritis (affecting renal pelvis and kidney) or bladder infection, the pain is severe and is usually associated with systemic features and urinary tract symptoms.

Acute upper ureteric obstruction and distension of the pelvicalyceal system produce excruciating loin pain. The pain is colicky (resulting from powerful ureteric peristalsis) and often radiates to the hypochondrium (right or left upper quadrant of the abdomen) or groin ( Fig. 34.1 ). This pain is known as renal or ureteric colic . When obstruction is low in the ureter, the pain may radiate to the genitalia.

Pain Arising From the Bladder and Lower Tract

Pain originating in the bladder (e.g., in cystitis) is experienced in the suprapubic area. Pain may be referred to the penis or vulva if the bladder trigone is involved. In adults, urinary symptoms, such as dysuria and frequency, are usually present as well, but children may have no localising symptoms or complain only of pain, making the diagnosis less obvious. Dysuria is usually the predominant symptom of urethral disorders, but pain arising in the male urethra (e.g., in sexually transmitted infections) is usually referred to the tip of the penis. Finally, the pain of prostatic inflammation (prostatitis) is usually felt deep in the perineum. The prostate is tender on rectal examination.

Pain Simulating Urinary Tract Disease

Pain from other abdominal pathology may sometimes mimic pain arising from the urinary tract. Acute appendicitis may present with suprapubic pain, and biliary tract pain may be referred to the right thoracolumbar region, while posterior duodenal ulcers and pancreatic disease may cause pain in the central lumbar region. An expanding or leaking abdominal aortic aneurysm may sometimes mimic urinary tract disease, particularly if a ureter is compressed, causing flank pain, which can be mistaken for renal colic. Diseases of the thoracolumbar spine, such as metastatic cancer, tuberculosis, spondylosis and disc lesions may also simulate upper urinary tract disorders. Suspected renal colic with a local rash is usually caused by shingles (herpes zoster); the rash may not appear for several days after the onset of pain; perineal zoster may cause retention of urine. In women, pain arising from the ovaries or genital tract (e.g., pelvic inflammatory disease) may be confused with bladder pain.

Causes of Haematuria ( Fig. 34.2 for Renal Causes)

Tumours are a common cause of visible and non-visible haematuria and must be suspected even if another possible cause is found. Haematuria from tumours is typically painless, although upper urinary tract bleeding can cause ‘clot colic’. However, carcinoma-in-situ of the bladder, a dysplastic condition with a high probability of progression to invasive carcinoma, usually presents with irritative voiding, dysuria, and haematuria, often with a finding of sterile pyuria (pus cell without proven bacteria) on urine testing. Irritation from infection or stones may also cause bleeding, but is usually accompanied by pain or dysuria. If the urethra is obstructed by prostatic enlargement, straining at micturition may cause bleeding from dilated veins at the bladder neck.

Trauma to a normal kidney may cause frank haematuria if substantial force has been applied, but non-visible haematuria is common after minor trauma in contact sports and rarely indicates significant injury. Enlarged kidneys are more susceptible to trauma, whatever the primary pathology. In hydronephrosis or polycystic kidneys, minor blunt trauma may cause gross haematuria.

Sometimes, urine becomes red with haemoglobin rather than blood. In young people this may be induced by vigorous exercise, such as jogging ( exercise haemoglobinuria and haematuria ). These patients are believed to have defective red cell membranes, which makes them more vulnerable to trauma. Exercise haemoglobinuria is self-limiting and requires no treatment.

Haematuria also occurs in renal parenchymal inflammation, such as glomerulonephritis or arteritis. Haematuria may be caused by microemboli impacting in the kidneys, as in atrial fibrillation or infective endocarditis. Any urinary tract disorder with a potential for haematuria is more likely to be revealed when a patient is on anticoagulant therapy or develops a bleeding diathesis.

Diagnostic Features of Haematuria

The stage of micturition at which blood appears is sometimes diagnostically useful. Blood from the kidneys, ureters or bladder wall will completely mix with the urine, and be present throughout the urinary stream. Urethral bleeding may leak out independently of micturition, or be seen only at the beginning or end of the urinary stream. Blood arising from the bladder neck or posterior urethra may sometimes present as terminal haematuria. Gross bleeding may result in the passage of clots.

Haematuria on dipstick testing can be confirmed by urine microscopy for red blood cells, and checked for infection by culture and sensitivity. Microscopic haematuria may represent a noteworthy lesion anywhere in the urinary tract and must be taken seriously; however, a significant cause is found in only 5% to 25% of patients.

Lower Urinary Tract Symptoms

These are divided into voiding (or obstructive) symptoms: hesitancy, poor stream, incomplete bladder emptying and terminal dribbling; and storage (or irritative) symptoms: frequency, nocturia, urgency and urge incontinence. Combinations of these symptoms can occur in prostatic obstruction; similar symptoms also occur in bladder neck obstruction, urethral stricture, bladder calculi and lower urinary tract infection. The severity of symptoms in men is assessed using the International Prostate Symptom Score (see Box 35.1 , p. 473).

Acute Retention

Acute urinary retention is often very painful and occasionally occurs in normal individuals, usually males, particularly postoperatively, when fluid overload, drugs, pain, the supine posture, anxiety or embarrassment are responsible. Similar factors may precipitate an episode in men with asymptomatic prostatic enlargement. Occasionally, acute retention is caused by an obstructing blood clot ( clot retention ) or stone.

In females, acute urinary retention may also occur in pregnancy, if the enlarging uterus becomes wedged in the pelvis at about 14 weeks’ gestation. Large ovarian cysts or uterine fibroids may cause similar obstruction. Other possible causes include neurological disorders, such as sacral nerve injury, multiple sclerosis, and following stress incontinence surgery (which increases the resistance of the bladder outlet and urethra). Fowler syndrome is an uncommon condition, which presents in young women as acute urinary retention caused by an underactive bladder, but is caused by a hypercontractile, non-relaxing external urethral sphincter. It is associated with urethral or pelvic pain, which limits the ability to tolerate urethral catheterisation. Alternative options to drain the bladder include insertion of a suprapubic catheter, or formation of a Mitrofanoff channel, which uses the appendix to provide a route to pass a catheter from the umbilicus or abdominal wall directly into the bladder, bypassing the urethra. Sacral nerve neuromodulation techniques can also be used to relax the sphincter to allow spontaneous voiding.

Chronic Retention

Chronic retention is often painless and occurs with structural or functional abnormalities of bladder muscle or the sphincter mechanism. Less commonly, it is caused by persistent urethral obstruction. In chronic retention, voiding of urine is often incomplete. The problem progresses until the residual volume approaches maximum bladder capacity. Voiding then usually occurs by ‘overflow’ and the bladder usually becomes abnormally distended. When obstruction is prolonged and severe, the bladder muscle hypertrophies, bladder diverticula may develop, and back pressure on the kidneys can cause uraemia and renal failure (high-pressure chronic retention). At any stage, complete cessation of flow, that is, acute-on-chronic retention , may be precipitated by overfilling (often alcohol induced), urinary tract infection or constipation. The most common cause of chronic retention is bladder outlet obstruction caused by a hypertrophied bladder neck or prostatic enlargement. It may also be caused by lower spinal neurological problems, for example, central protrusion of lumbar intervertebral discs damaging the S2, 3, 4 detrusor muscle innervation.