Inflammation caused by the invasion of pathogenic bacteria into the genitourinary male genital system to multiply is called genitourinary male infection. Most of the causative organisms are gram-negative bacteria. Because of the anatomical features, the close relationship between the urinary and genital tracts, and the connection between the urethral opening and the outside world, infections of the female urinary tract and genital tract often occur simultaneously or spread to each other.
Urinary tract infections are also known as urinary tract infections. Pyelonephritis and ureteritis are upper urinary tract infections. Cystitis and urethritis are lower urinary tract infections, and the former (upper urinary tract) is often complicated by lower urinary tract infections. The latter can be present alone. Urinary tract infections are highly prevalent and are second only to respiratory tract infections in terms of incidence of infectious diseases.
The most common pathogenic bacteria are from intestinal bacteria, 60%-80% of which are Escherichia coli, others such as Escherichia coli, Proteus mirabilis, Staphylococcus, Streptococcus faecalis, alkali-producing bacteria, and Pseudomonas aeruginosa (Pseudomonas aeruginosa). In addition, there are Mycobacterium tuberculosis, gonococcus, chlamydia, mycoplasma, trichomonas, anaerobes, fungi, protozoa, or viruses. Mycobacterium tuberculosis causes specific infections of the urinary and male genital systems.
Normal human urethral skin and mucous membrane have some bacteria stay, such as lactobacillus, streptococcus, staphylococcus, small rod bacillus, etc. called normal flora, in the pathogenic bacteria have not reached a certain number and virulence, normal flora can play a role in inhibiting the balance of pathogenic bacteria. And normal human urine pH and high osmotic pressure, urine contains urea and organic acids are not conducive to the reproduction of bacteria, and the bladder urination activity can be flushed out bacteria, so the normal infection has a defensive function.
I. Factors that induce infection
Due to the anatomical and physiological characteristics of the urinary and genital system, pathogenic bacteria are not easily able to stay and multiply under normal circumstances, so it is not appropriate to cause infection. However, once the genitourinary system is pathologically altered, the defensive function of infection is destroyed and pathogenic bacteria take advantage of the situation, thus inducing infection. The factors that induce infection are mainly from four aspects.
1, obstructive factors: such as congenital genitourinary abnormalities, stones, tumors, strictures, prostatic hyperplasia or neurogenic bladder, causing urine retention and reproduction, reducing the ability of the urinary tract and genital tract epithelial defense against bacteria.
2, weakened body resistance: such as diabetes, pregnancy, anemia, chronic liver disease, malnutrition, tumors and congenital immunodeficiency or long-term application of immunosuppressive therapy.
3, medical factors: such as indwelling catheterization fistula urethral dilatation prostate puncture biopsy cystoscopy and other operations, due to mucosal insertion injury or disregard for the concept of asepsis, easy to introduce pathogenic bacteria and induce or spread infection.
4, other: the female urethra is shorter, easy to attract upstream infection, menstruation, menopause, sexual intercourse is more likely to occur. During pregnancy, the ureteral orifice is relaxed due to endocrine and mechanical reasons, and urine discharge is delayed, making it easy for upstream infection. The urethral orifice deformity or infection lesions near the urethral orifice such as paraurethral adenitis and vaginitis are also triggers of infection.
Second, the route of infection
There are four main types of infection, the most common is the upstream infection and bloodstream infection.
1, upstream infection: the pathogenic bacteria through the urethra into the bladder, but also along the ureteral cavity spread to the kidney. About 50% of lower urinary tract infections lead to upper urinary tract infections, because cystitis appears as mucosal edema, which changes the function of the ureteral bladder junction and predisposes to urinary reflux, and pathogenic bacteria can reach the kidney directly. Upstream infections are more likely to occur if the bacteria have special adhesion or if normal ureteral peristalsis is impaired. Such infections often occur in women during the newlywed period, pregnancy, infants and children, as well as patients with urinary tract obstruction and the causative agent is mostly Escherichia coli.
2, bloodstream infection: less common, in the body’s immune function is low or some factors promote, skin boils canker tonsillitis otitis media and other infectious foci of bacteria directly and bloodstream transmission to the genitourinary organs, commonly for the renal cortex infection pathogenic bacteria are mostly Staphylococcus aureus.
3, lymphatic infection: the pathogenic bacteria from the foci of neighboring organs to the genitourinary organs through the lymphatic vessels, such as serious infections of the intestinal tract or retroperitoneal abscesses, is a much less common route of infection.
4. Direct infection: due to direct spread of infection from neighboring organs, such as appendiceal abscess, purulent inflammation of the pelvis or foreign infection, infection of pathogenic bacteria through fistulas and foreign bodies in the kidney area.
III. Diagnostic methods
Urinary and male genital infections generally have more typical clinical manifestations, especially in the acute stage, and the diagnosis is not difficult. However, in the diagnosis, attention must be paid to the search for the lesion and its pathological basis, and there should be an accurate estimation of the pathogen and the extent of the lesion. Confirmation of urinary tract infection depends first of all on the presence of bacteria or white blood cells in the urine. Since the diagnosis is often confused by contamination during specimen retrieval, the correct method of collecting urine specimens is an important part of the diagnosis.
1. Collection of urine specimens.
There are three ways:
(1) segmental collection of urine, generally using the middle segment of urine.
(2) Catheterization is commonly used in female patients.
(3) suprapubic cystocentesis, most suitable for newborns and paraplegics, the most reliable urine specimens are retained by this method. Urine cultures are often obtained from clean mid-stage urine or suprapubic bladder puncture specimens.
Urine specimens should be processed within 2 hours after collection to avoid contamination and miscellaneous homogeneous growth.
2, urine microscopy
Urine specimens should generally be examined in immediate smear, the simplest method is to stain a drop of fresh urine with US blue, microscopic observation can be seen gram-negative rods or positive cocci, another part and then send urine bacterial culture and drug sensitivity test.
In addition, the urine sediment is examined for the presence of white blood cells, and if there are more than 5 white blood cells per high-powered field of view, it is considered pus urine, suggesting a urinary tract infection. Pus urine without bacteriuria should be alert to the presence of tuberculosis, stones and tumors.
3.Bacterial culture and colony count
This is the main basis for the diagnosis of urinary tract infection.
If the colony count is more than 105/ml should be considered as having infection, less than 104 may be contamination, and the culture should be repeated, between 104-105 is suspicious. This value is meaningful in acute urinary tract infections and cases where antibacterial drugs have not been applied, but it is often difficult to judge in chronic cases and those who have used drugs, and must be analyzed in combination with clinical symptoms to make a decision.
4.Localization examination
Urinary tract infections are divided into upper and lower urinary tract infections, upper urinary tract infections are represented by pyelonephritis, and lower urinary tract infections are mainly cystitis, the treatment and prevention of which are different and must be clinically differentiated.
The methods of differentiation include identification of symptoms, urine microscopy, urine culture, urine fluorescence immunoassay and cystoscopy.
5.Imaging
These include ultrasound, plain urine film, excretory urography, cystography or urethrography, CT, radionuclide and magnetic resonance water imaging.
The examination is especially needed for chronic infections and patients who have been untreated for a long time. Its significance is to.
(1) To clarify the presence or absence of urinary tract abnormalities.
(2) The presence of obstructive lesions.
(3) The presence of combined stones, tumors and prostatic hyperplasia.
(4) whether the urodynamics is impaired.
(5) The presence or absence of renal impairment on both sides and left-right comparison.
(6) presence of bladder-ureteral reflux
(7) Monitor the residual urine and the emptying time of the renal pelvis and bladder.
IV. Treatment principles.
1, clarify the nature of the infection: clinical symptoms of urinary tract infection, the nature of the infection and the causative organisms must be clarified, based on the results of urine bacterial culture and drug sensitivity test report, and targeted drug use, which is the key to treatment, but there is no urine bacterial culture results, according to the urine sediment smear Gram stain preliminary estimate of the causative organisms, select the appropriate drugs.
2, identify the upper urinary tract infection or lower urinary tract infection: in the treatment of the two are different, the former heavy symptoms, poor prognosis, easy to relapse, the latter light symptoms, good prognosis, less relapse.
3, clarify whether it is bloodstream infection or upstream infection: bloodstream infection has a rapid onset, with chills and high fever and other systemic symptoms, apply antibacterial drugs with high blood concentration; upstream infection is mainly bladder irritation, apply antibacterial drugs with high urine concentration and antispasmodic drugs.
4, identify the presence of urinary tract obstruction factors: urinary tract obstruction is often a direct cause of urinary tract infection, while the presence of obstruction after infection, it is not easy to cure, easy to produce drug-resistant strains, but also easy to recur, requiring surgical drainage or lifting the obstruction.
5.Check whether there are any precipitating factors of urinary tract infection: correct them.
6.Measure the PH value of urine: The PH value of urine should be measured before treatment. If it is acidic, it is appropriate to use alkaline drugs, such as sodium bicarbonate, to alkalize the urine to inhibit the growth of pathogenic bacteria and use antibacterial drugs suitable for alkaline environment. On the contrary, if the urine is alkaline, it is appropriate to use acidic drugs, such as vitamin C, ammonium chloride plus urotropine, etc., with antibacterial drugs adapted to the acidic environment.
7, the correct use of antibiotics.
The purpose of treating urinary tract infections is to achieve sterile urine.
As a result, treatment must pay attention to the presence of sufficient concentration of antibacterial drugs in the urine, rather than simply relying on the concentration of drugs in the blood, and the concentration in the urine should be hundreds of times higher than the concentration in the blood in order to achieve the purpose of treatment.
An appropriate antimicrobial drug treatment should render the urine sterile within a few hours, and this treatment needs to be maintained for 7-10 days before determining whether the bacterial culture has turned negative; if the colony count is suppressed to a few hundred or less per milliliter, relapse occurs soon after discontinuation of the drug. Therefore, the use of antibacterial drugs should be maintained in principle until the disappearance of symptoms and 2 weeks after the urine bacterial culture.
In the process of antibacterial treatment, bacteria will mutate and change from highly sensitive to one antibiotic to resistant strains. To avoid the development of resistant strains two or more antibacterial drugs can be applied simultaneously.
If you have a history of infection, urinary tract obstruction and other causative factors, you must extend the duration of medication, while eliminating the causative factors at the right time, such as surgical drainage or lifting the obstruction, and not rely solely on drugs.