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Percutaneous nephrostomy tube, if a ureteral catheter is not possible

Perinephric abscess is thought to occur usually from renal extension of ascending infection.

Clinical presentation varies among patients.

Fever, chills, and flank pain are common.

Symptoms may persist after appropriate antimicrobial therapy.

Diagnosis. Ultrasound and computed tomography (CT) scan are the best methods.

Treatment can include the following:

Percutaneous aspiration and drainage

Relieving obstruction if present (e.g., removal of a ureteral catheter)

Antimicrobial therapy

G Prostatitis/Chronic pelvic pain syndrome is a spectrum of infectious and noninfectious diseases of the prostate gland

Clinical presentation includes urinary frequency, urgency, perineal pain or fullness, and dysuria.

Subsets include acute bacterial prostatitis, chronic bacterial prostatitis, nonbacterial prostatitis, and prostatodynia (Table 25 -1).

Diagnosis

Acute bacterial prostatitis presents with most of the aforementioned symptoms plus a fever. Prostatic massage should not be performed to avoid bacteremia.

Urinalysis. Patients with acute bacterial prostatitis usually have inflammatory findings on urinalysis.

Expressed prostatic secretions (EPS) , which are fluid obtained by digital massage of the prostate, are tested for leukocytes in chronic inflammatory conditions.

Bacteriologic etiology

Young men (younger than 50 years of age). Chlamydia and gram -negative organisms predominate.

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TABLE 25-1 Diagnostic Features of Prostatitis/Chronic Pelvic Pain Syndrome

WBC, white blood cell count; EPS, expressed prostatic secretions.

Elderly men (older than 50 years of age). Gram-negative organisms are the most common pathogens.

Treatment

Acute bacterial prostatitis

Trimethoprim-sulfamethoxazole for 30 days

Fluoroquinolone for 30 days

Parenteral therapy with ampicillin and gentamicin or vancomycin, if the patient is systemically ill or has a complicated UTI

Chronic bacterial prostatitis. Treatment is based on culture and sensitivity.

Trimethoprim-sulfamethoxazole for 6 weeks

Fluoroquinolone for 6 weeks

To treat symptomatic episodes or to consider suppression if therapy is ineffective (which it commonly is)

Nonbacterial prostatitis

Doxycycline for 4–6 weeks

Symptomatic control, including sitz baths

Prostatodynia. Because the cause may be multifactorial and include poorly understood, treatment is evolving.

Symptomatic control with empirical antimicrobial therapy

α-Adrenergic antagonists

Trycyclic antidepressents or membrance stabilizing agent (e.g. gabapentin)

Muscle relaxants (e.g., diazepam)

Biofeedback

Stress reduction techniques

Saw Palmetto and Pygeum extracts; anti -irritants to the prostate

II Urinary Calculi

A Etiologic theories

Supersaturation and crystallization

Uric acid and cystine calculi form when urine with an acid pH less than 6.0 becomes oversaturated with uric acid or cystine.

Struvite (magnesium ammonium phosphate) calculi form when the magnesium ammonium phosphate ions exist in an alkaline urine.

Inhibitor deficiency. Inhibitors (e.g., high molecular weight glycoproteins, citrate, magnesium, phosphates [pyrophosphate], zinc) that exist in the urine and can retard stone formation may be lacking.

B Types of urinary calculi

Calcium oxalate calculi are the most common stones. They are radiopaque owing to the calcium ion. They exist in monohydrate (more radiodense) and dihydrate forms.

Uric acid calculi are radiolucent stones that are formed from excess urinary uric acid levels.

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Cystine calculi are faintly radiopaque because of the sulfur ion.

Cause. Cystinuria is an autosomal recessive disorder that results in a defect in renal tubular reabsorption of four amino acids: cystine, ornithine, arginine, and lysine. Only cystine forms calculi.

Heterozygotes will most likely not form calculi; homozygotes invariably form multiple calculi.

Cystine calculi form because of the low solubility of cystine in urine with a pH less than 7.0.

Prevention. Overhydration and urine alkalinization to pH 7.5 are the most effective preventive measures. Oral cystine-binding drugs, such as D-penicillamine or α-mercaptopropionylglycine, also help to prevent stone formation.

Treatment of existing stones is usually multimodal with percutaneous procedures, extracorporeal shock -wave lithotripsy (ESWL), and dissolution therapy (percutaneous). Dissolution solutions include N-acetylcysteine or bicarbonate.

Struvite calculi are also radiopaque. They are usually related to chronic UTIs with urea -splitting bacteria, which maintain an alkaline urine:

Proteus, which is most common

Providencia

Pseudomonas

Klebsiella

C Clinical presentation

The most frequent symptom is pain, which is caused by ureteral obstruction. The site of pain is related to the location of the obstructing calculus (e.g., flank pain, lower abdominal pain, testicular pain, or vulvar pain). Other symptoms that can occur include:

Hematuria (visible or microscopic)

Nausea and vomiting

Irritative bladder symptoms (e.g., from a ureterovesical junction calculus)

D Diagnosis

Physical examination. Patients are usually in distress and have costovertebral angle tenderness. Occasionally, an associated paralytic ileus can occur, which must be differentiated from an acute abdomen.

Urinalysis

Hematuria is usually present.

A uric acid stone is unlikely to be found in a patient with a urine pH of 6.5 or higher.

Noncontrast spiral computed tomography (CT) is now the diagnostic test of choice. This procedure is less costly, less time consuming, without contrast and is very accurate; however, although improvements are being made, it is not yet as informative as intravenous pyelography (IVP).

Excretory urography (IVP) can be useful to delineate complex anatomy or as alternative to CT (Fig. 25 -1).

Renal function should be assessed before IVP to avoid contrast nephrotoxicity.

IVP should define stone size, location, and degree of obstruction.

Ultrasonography is best used in patients with elevated serum creatinine or with a severe allergy to contrast media. It defines hydronephrosis or an acoustic shadow from a calculus. Ultrasonography is often used in conjunction with a plain abdominal radiograph.

Cystourethroscopy and retrograde pyelography may need to be used to confirm the presence of a calculus and reveal its location if it is difficult to identify the calculus on imaging studies.

E Treatment

Indications for emergency surgery include:

Fever. Obstructive calculi in a patient with a fever requires emergent decompression of the obstructed system. This is best accomplished through cystoscopy and retrograde placement of a ureteral catheter or stent. No further manipulation of the calculus should be performed

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at that time because of the risk of sepsis. If the obstructed system is unable to be decompressed in this manner, a percutaneous nephrostomy tube should be placed.

FIGURE 25-1 IVP; preliminary film (left) reveals a radiointensity (right) between L2 and L3. After injection of intravenous contrast, the density is seen obviously in the proximal ureter with resultant hydrouteronephrosis.

Renal insufficiency. An elevated serum creatinine level or ureteral calculi requires urgent ultrasonography. Similarly, cystoscopy with retrograde pyelography can further delineate an anatomic problem, and stent placement may be necessary. A classic situation is the solitary kidney with an obstructing calculus.

Observation for spontaneous stone passage

The patient must have adequate pain control (orally), an ability to take liquids by mouth, and a stone that has a favorable chance of passing.

The likelihood of spontaneous passage is related to the size of the stone and the site of obstruction. Most distal ureteral calculi of 5 mm or less will pass spontaneously.

Surgical procedures. Advances in endoscopic techniques, ESWL, and endourology successfully allow most calculi to be removed without open surgical procedures.

Indications for intervention include:

Severe pain

Nonprogression of calculus passage

Infection (emergent)

Prolonged obstruction

Interference with lifestyle

Percutaneous nephrostomy procedures allow renal calculi to be approached through a nephrostomy tube tract in the flank. This is best suited for large calculi that can be fragmented and removed using ultrasonic, electrohydraulic, or laser lithotriptors.

Ureteroscopic procedures. A transurethral approach into the ureter is best for calculi in the distal half of the ureter but may also be used for upper ureteral and renal calculi.

Calculi can be “grabbed” in a wire basket and removed intact, or laser, electrohydraulic, or ultrasonic lithotriptors may be used to fragment calculi.

A stent is often left in the ureter after manipulation to alleviate obstruction from edema.

ESWL can be used for renal or ureteral calculi. It consists of an external energy source, which is focused by fluoroscopic or ultrasound guidance on a calculus to provide a high-pressure zone that can fragment the calculus. The gravel-like fragments pass through the ureter.

Complications include bleeding, perinephric hematoma, “steinstrasse” (gravel causing ureteral obstruction), and hypertension.

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Contraindications include coagulopathy, antiplatelet medications, or infection. Simultaneous bilateral treatment is contraindicated.

F Metabolic evaluation and prophylaxis

Patients who require a metabolic evaluation to determine the etiology of their calculus formation include young people (younger than 40 years of age) experiencing their first calculus event, people with multiple calculi, and people with recurrent stone formation. Most of these patients will have a metabolic abnormality that can be benefited by medical therapy. All patients require radiographic assessment to rule out anatomic causes for calculi formation, such as obstruction with urinary stasis.

G Analysis of calculi

The retrieved calculus or fragments should be analyzed to determine their composition.

Calcium-containing calculi consist mainly of calcium oxalate or calcium phosphate.

Serum chemistry, urinalysis, and 24 -hour urine collection for calcium, oxalate, phosphate, uric acid, citrate, and creatinine are performed.

The goal is to differentiate the various causes of calcium stone formation , such as:

Renal hypercalciuria (leak of renal calcium)

Absorptive hypercalcuria (excessive gastrointestinal absorption of calcium)

Hyperparathyroidism

Normocalciuria

Renal tubular acidosis (in association with sarcoidosis, hypercalcemia, vitamin D intoxication, immobilization syndrome)

Treatment for calcium-containing calculi includes:

Hydration to maintain a urine output greater than 2 L/day

Thiazide diuretics for renal hypercalcuria

Orthophosphates (absorptive hypercalcemics) to bind calcium in the gastrointestinal tract

Citrate to increase urinary citrate, which is an inhibitor of calculus formation

Low-calcium diet

Struvite calculi require the presence of urea -splitting bacteria, which maintain an alkaline urine environment.

Proteus is the most common pathogen.

Treatment. Removal of all stone fragments plus eradication of infection is imperative. Frequently, the patient requires a combination of percutaneous and ESWL treatment. Percutaneous dissolution therapy is sometimes used on remaining small fragments.

Uric acid calculi are radiolucent on plain radiographs and dense (white) on a CT scan. They form in acid urine pH (i.e., pH <6.0). Alkalinization of urine to pH 7.0 will dissolve uric acid calculi. Potassium citrate or sodium bicarbonate is also effective. If hyperuricemia is present, allopurinol should be added for prevention of future calculi.

Cystine calculi (see II B 3)

III Benign Prostatic Hyperplasia

Benign prostatic hyperplasia (BPH) is a benign enlargement of the prostate gland that occurs commonly in aging men. Histologic changes include stromal and epithelial hyperplasia in the transition (periurethral) zone, which can compress the prostatic urethra and obstruct urinary flow. This process depends on testosterone, but the exact etiology remains unknown. The clinical sequela of BPH, lower urinary tract symptom (LUTS) , occur in only a subset of patients with histologic BPH. Obstruction is thought to have a static component (mechanical) and a dynamic component (bladder neck, prostatic capsule, and urethral tone).

A

Diagnosis is based on the patient's symptoms and findings on digital rectal examination (DRE). Cold weather, ingestion of alcohol, narcotics, antihistamines, anticholinergics, and holding urine for prolonged periods may exacerbate symptoms or precipitate urinary retention.

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Symptoms

Obstructive voiding symptoms of BPH. These symptoms tend to respond best to treatment.

Diminished force of urinary stream despite a full bladder

Hesitancy in initiating flow

Sense of incomplete emptying

Intermittency or “double voiding”

Urinary retention

Irritative voiding symptoms. These are thought to be caused by detrusor instability from chronic obstruction.

Frequency

Urgency, possibly urge incontinence

Nocturia

Dysuria

The International Prostate Symptom Score is a seven -item validated questionnaire that is useful to quantify severity of LUTS. Scores range from 0 to 35 and are subdivided into Mild (0– 7), Moderate (8–19), and Severe (19–35).

Physical examination and diagnostic testing include:

Palpation of the gland to assess size, consistency, and presence or absence of induration (risk of cancer)

Palpation of a suprapubic mass consistent with a full bladder

Hematuria (microscopic or gross)

Prostatic-specific antigen (PSA) (optimal)

Assessment of residual urine volume via transabdominal ultrasonography or direct catheterization

Uroflowmetric findings of diminished flow rate and prolonged voiding, or urodynamic evidence of low flow rate despite high intravesical pressure Optional Additional Tests

Cystourethroscopy to assess visual obstruction, bladder trabeculation, cellule or diverticuli formation, or bladder calculi. (None of these findings is specific for BPH, and each can be present in the absence of significant symptoms.)

Transrectal ultrasonography (TRUS) to demonstrate enlargement and allow estimation of the volume of prostatic tissue, and biopsy if a significant risk of cancer exists

IVP to demonstrate an enlarged prostatic impression on the inferior bladder, bladder wall thickening, hydroureteronephrosis, “J hooking” of the distal ureters, or bladder calculi. (IVP is no longer a standard part of the evaluation but may be included if infection or hematuria is present.)

B Treatment

Indications for treatment. Absolute indications for intervention include:

Urinary retention

Significant or recurrent gross hematuria not due to other causes.

Bladder calculi

Bilateral hydroureteronephrosis with renal insufficiency secondary to bladder outlet obstruction

Repeated UTIs caused by urinary stasis

Most men initiating treatment do so for relief of symptoms rather than any absolute indication.

Goals of treatment include: