Obstruction urethral

Obstructive lesions exist in a considerable number of patients, although the proof of an uro-dynamically significant obstruction is difficult. As documented in 12 studies comprising 151 patients mainly studied postmortem, 84 had obstructive urethral lesions (Wheatley et al. 1996). If the theory of urethral obstruction as a primary defect in prune belly syndrome is correct, the timing and severity of the obstruction must be distinct from other obstructive uropathies, particularly from posterior urethral valves. 

There are also drugs which by themselves can cause kidney failure. The mechanisms behind drugs negative effects on the kidneys are multiple. Among the most important is diminished blood flow to the kidneys (prerenal failure). Others are immunological damages to the nephrons caused by deposition of autoimmune complexes or direct nephrotoxicity caused by for example, antibiotics. The kidney function can also be damaged by post-renal obstructions, for example, kidney stones, urethral strictures or prostate hyperplasia (Ashley 2004). 

Benign prostatic hypertrophy Patients with benign prostatic hypertrophy may develop acute urethral obstruction. Priapism or excessive sexual stimulation may develop. Oligospermia may occur after prolonged administration or excessive dosage. 

Benign prostatic hyperplasia. Age-associated enlargement of the prostate, resulting from proliferation of both glandular and stromal elements, beginning generally in the fifth decade of life. It may cause urethral compression and obstruction. 

As BPH progresses, the excess tissue results in prostatic enlargement and causes urethral obstruction. This obstruction is typically associated with characteristic symptoms such as hesitancy in starting urination, diminished urine stream size and force, involuntary interruptions in stream, and a sensation of incomplete bladder emptying (Claridge, 1966). In men with BPH, the mean decrease in maximum urinary flow rate is about 0.2 ml/s/year (Ball et al, 1981). 

Lower tract infections include cystitis (bladder), urethritis (urethra), prostatitis (prostate gland), and epididymitis. Upper tract infections (such as pyelonephritis) involve the kidney and are referred to as pyelonephritis. Uncomplicated UTIs are not associated with structural or neurologic abnormalities that may interfere with the normal flow of urine or the voiding mechanism. Complicated UTIs are the result of a predisposing lesion of the urinary tract such as a congenital abnormality or distortion of the urinary tract, a stone, indwelling catheter, prostatic hypertrophy, obstruction, or neurologic deficit that interferes with the normal flow of urine and urinary tract defenses. 

Goscrelin Transient increase m bone p-iin and urethral obstruction in patients with metastatic prostatic cancer hoc flushes Impotence testicular atrophy gynaccoma tia... 

Biological agents BCG (Bacilli Calmette-Guerin) Acute toxicity Bladder irritation nausea and vomiting fever sepsis Delayed toxicity Granulomatous pyelonephritis hepatitis urethral obstruction epididymitis renal abscess... 

A 15-year-old boy with Lennox-Gastaut syndrome taking felbamate (3000 mg/day), topiramate(200 mg/ day), and lorazepam developed painful hematuria, bilateral urethral obstruction, and urinary retention. Kidney, bladder, and urethral stones were found. The stone material was identified as felbamate by chemical analysis. However, as the patient was also taking topir-amate the association with felbamate was uncertain. 

Refluxing ureters can be treated endoscopically with sub-ureteric injection of polytetrafluoroethylene paste (Polytef), the STING procedure. However, ureteric obstruction has been described as a complication (8). Urinary incontinence has also been treated by periurethral or submucosal injections of Polytef, but reports of urinary obstruction (9,10) and poor long-term success (11,12) have limited the range of indications for this treatment. Other reported complications of Teflon injection for stress urinary incontinence include periurethral abscess, urethral diverticulum. Teflon granuloma with urethral wall prolapse (13), and microembolization (14). 

Suramin was not effective in one phase II study in advanced renal cell carcinoma, in which it was given in a fixed dose plus hydrocortisone to 22 patients (19 men, three women, aged 30-74 years) (11). Three patients had grade 4 toxicity (hypersensitivity, urethral obstruction, hypotension, and neutropenic sepsis). Eleven developed grade 3 toxicity, mainly abdominal pain, anemia, diarrhea, erythema, dyspnea, fatigue, and fever. 

Urethral overactivity is most commonly cansed by anatomic obstruction. Anatomic obstmction in men is most often caused by benign prostatic enlargement, which is discnssed in Chap. 82. 

Phenoxybenzamine and phentolamine have been shown to be effective in the relief of urethral obstruction induced by benign prostatic hyperplasia (BPH). Norepinephrine-induced contraction of isolated human prostate was shown to result from a -adrenoceptor activation (Hieble etal., 1985), and selective a,-adrenoceptor antagonists have been proven to be effective drugs for BPH (Eri and Tveter,... 

Azithromycin, an azalide macrolide antibiotic (500 mg p.o. as a single dose on day 1, followed by 250 mg daily on days 2 to 5 total accumulation dose is 1.5 g), is indicated in the treatment of acute bacterial exacerbations of chronic obstructive pulmonary disease caused by Haemophilus influenzae, Moraxella (Branhamella) catarrhalis, or Streptococcus pneumoniae mild community-acquired pneumonia caused by H. influenzae or S. pneumoniae uncomplicated skin and skin-structure infections caused by Staphylococcus aureus, Streptococcus pyogenes, or S. agalactiae second-line therapy of pharyngitis or tonsillitis caused by S. pyogenes and in nongonococcal urethritis or cervicitis caused by Chlamydia trachomatis. 

The symptoms of BPH (c.g., urethral obstruction leading to weak stream, urinary frequency, and nocturia) result from mechanical pressure on the urethra (due to an increase in smooth muscle mass) and an a -mediated increase in smooth muscle tone in the prostate and neck of the bladder. 

Oligoanuric acute renal failure has been described in patients on phenylbuta-zone ". A pathogenetic mechanism reponsible is the inhibition of the tubular reabsorption of uric acid, which results in hyperuricosuria, uric acid crystallization and, eventually, urethral obstruction. Another form of this syndrome, in which there is no evidence of hyperuricaemia, is felt to be an idiosyncratic reaction. The biopsy picture is consistent with acute tubular necrosis. ... 

Posterior urethral stenoses can be studied with voiding cystourethrography and voiding cystoure-throsonography and may be divided into vesical neck obstructive syndrome and post-prostatectomy stenosis. 

Hoebeke PB, Van Laecke E, Raes A et al (1997) Membrano-bulbo-urethral junction stenosis. Posterior urethra obstruction due to extreme caliber disproportion in the male urethra. Eur Urol 32 480-484 Kawashima A, Sandler CM, Wasserman NF et al (2004) Imaging of urethral disease a pictorial review. Radiographics 24 [Suppl 1] S195-216... 

Prune belly syndrome Deficient abdominal muscles, urinary obstruction/ distension, cryptorchism, malrotation of the gut, clubfeet, limb reduction anomalies Urethral atresia, ureteral duplication, bladder distension, hydronephrosis, renal dysplasia Mostly sporadic, heterogeneous (100100)... 

An urinoma may complicate a UPJ obstruction. This type of complication may occur already in utero. It is more common with posterior urethral valves and acts like a protecting mechanism against obstruction (Avni et al. 1987 Genes and Vachon 1989). 

Abnormal duplex kidneys used to be and are still detected during the work-up of urinary tract infection or urinary dribbling in girls. They are more and more often demonstrated during fetal life. In utero, it is possible to differentiate between the two collecting systems particularly if one is dilated. It is even possible to differentiate between ectopic ureter and ucele in utero (Joseph et al. 1989 Avni et al. 1991 Abuhamad et al. 1996 Vergani et al. 1999 Caione et al. 1989 Jee et al. 1993). Other forms of presentation include interlabial mass in girls or bladder outlet obstruction. Both conditions are related to urethral prolapse of the ucele (Nussbaum 1983). 

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