Urethra

Theory and Equipment. Many diseases of the human body can be identified by visual appearance. Tumors in the upper gastrointestinal (GI) tract, for example, possess a characteristic salmon pink color (3). The presence of such a color can be an indication of disease. Endoscopy is the medical imaging tool used to detect such colors in the inside of hoUow internal organs such as the rectum, urethra, urinary bladder, stomach, colon, etc. An endoscope is the instmment used to perform endoscopy. Endoscopic imaging involves the production of a tme color picture of the inside of the human body using lenses and either hoUow pipes, a fiber optic bundle, or a smaU CCD camera. AU three use a large field-of-view, sometimes referred to as a fish eye, lens to aUow a 180° field of view. 

Hamblasen-. (Anat.) vesical, vesico-. -gang, m. (Anat.) urethra. 

Solids (eg, suppositories) or jellies inserted into the urethra... 

This chapter discusses drug s used to treat urinary tract infections (UTIs) and certain miscellaneous drag > used to relieve the symptoms associated with an overactive bladder (involuntary contractions of the detrusor or bladder muscle). Structures of the urinary system that may be affected include the bladder (cystitis), prostate gland (prostatitis), the kidney, or the urethra (see Pig. 47-1). These drug s also help control the discomfort associated with irritation of the lower urinary tract mucosa caused by infection, trauma, surgery, and endoscopic procedures. 

Urinary tract infection (UTI) is an infection caused by pathogenic microorganisms of one or more structures of the urinary tract. The most common structure affected is the bladder, with the urethra, prostate, and kidney also affected (see Pig. 47-1). Display 47-1 identifies the disorder most frequently associated with each of these structures within the urinary system. Clinical manifestations of a UTI of the bladder (cystitis) include urgency, frequency, burning and pain on urination, and pain caused by spasm in the region of the bladder and the suprapubic area. 

Cys/tt/sUnflammation of the bladder i/reffirft/sUnflammation of the urethra Prosfaf/f/s-inflammation of the male prostate gland Pyefonephritis-inflammation of the kidney and renal pelvis... 

In healthy individuals, the bladder, ureters and urethra are sterile and sterile urine constantly flushes the urinary traet. Organisms invading the urinary traet must avoid being detached Ifom the epithelial surfaces and washed out during urination. In the male, since the urethra is long ica. 20 cm), bacteria must be introduced directly into the bladder, possibly through eatheterization. In the female, the urethra is much shorter... 

The penis consists of three components, two dorsolateral corpora cavernosa and a ventral corpus spongiosum that surrounds the penile urethra and distally forms the glans penis. The corpora cavernosa consist of blood-filled sinusoidal or lacunar spaces, which are lined with endothelial cells, supported by trabecular smooth muscle, and surrounded by a thick fibrous sheath called the tunica albuginea. The caver-nosal arteries, which are branches of the penile artery, penetrate the tunica albuginea and supply blood flow to the penis. 

O The lower urinary tract symptoms and signs of benign prostatic hyperplasia are due to static, dynamic, or detrusor factors. The static factor refers to anatomic obstruction of the bladder neck caused by an enlarged prostate gland. The dynamic factor refers to excessive stimulation of a-adrenergic receptors in the smooth muscle of the prostate, urethra, and bladder neck. The detrusor factor refers to irritability of hypertrophied detrusor muscle as a result of long-standing bladder outlet obstruction. 

The prostate is a heart-shaped, chestnut-sized organ that encircles the portion of the proximal urethra that is located at the base of the urinary bladder. The prostate produces secretions which are part of the ejaculate. 

Urinary incontinence can result from abnormalities within (intrinsic to) and outside of (extrinsic to) the urinary tract. Within the urinary tract, abnormalities may occur in the urethra (including the bladder outlet and urinary sphincters), the bladder, or a combination of both structures. Focusing on abnormalities in these two structures, a simple classification scheme emerges for all but the rarest intrinsic causes of UI. Accurate diagnosis and classification of UI type is critical to the selection of appropriate drug therapy. 

Stimulating a adrenoceptors in the smooth muscle of the proximal urethra and bladder neck... 

Uncomplicated infections of the cervix, urethra, and rectum can be treated with one of the following regimens in adults ... 

Uncomplicated Infections of the Cervix, Urethra, and Rectum in Children (less than 45 kg)... 

Since HSV is only found in humans, infection may only be transmitted from infectious secretions onto mucosal surfaces (i.e., cervix or urethra) or abraded skin. It has also been noted that the virus may survive for a limited amount of time on environmental surfaces. 

Intravenous pyelogram Radiograph of the urinary tract, including the kidney ureters, urinary bladder, and urethra radiographic... 

Lower urinary tract infection (UTI) Includes infections of the bladder, urethra, and (in men) prostate and epididymis. 

Prostate An organ in the urogenital tract that surrounds the urethra at the base of the urinary bladder. Prostatic secretions are secreted into the urethra and become part of the ejaculate in males. 

Prostate-specific antigen (PSA) a substance secreted by the prostate and normally carried by ducts to the urethra during ejaculation PSA is used as a screening test for prostate cancer. 

Urethral stricture Fibrosis and scarring of the urethra that results in narrowing of the urethral lumen. 

Bladder tumor-associated antigen (BTA), a human complement factor H, is produced by bladder cancer cells (men two to three times as often as women). Cancer cells are sometimes seen in urine samples by microscope cytoscopy (examination of the bladder with an instrument inserted into the urethra), which can reveal abnormal areas. Biopsy is needed to confirm the diagnosis. Early stage cancer confined to the bladder wall can often be removed with a cytoscope. If several tumors are present, they are removed by infusing the bladder with a solution containing bacteria able to stimulate the immune system. 

Site of infection Most common-urethra Others-rectum (usually due to rectal intercourse in men who have sex with men), oropharynx, eye Most common-endocervical canal Others-uretfira, rectum (usually due to perineal contamination), oropharynx, eye... 

Type of Infection Uncomplicated infections of the cervix, urethra, and rectum in adultsc,d Recommended Regimens0 Ceftriaxone 125 mg IM once/ or cefixime 400 mg po once/5 or ciprofloxacin 500 mg po once/ or ofloxacin 400 mg po once/ or levofloxacin 250 mg po once plus A treatment regimen for presumptive C. trachomatis coinfection if chlamydial infection has not been ruled out (see Table 121 -8 in Pharmacotherapy A Pathophysiologic Approach, seventh edition)... 

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. 

In females, the short length of the urethra and proximity to the perirectal area make colonization of the urethra likely. Bacteria are then believed to enter the bladder from the urethra. Once in the bladder, the organisms multiply quickly and can ascend the ureters to the kidney. 

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