Upper Tract Infections Research Articles

Management of Acute Uncomplicated Urinary Tract Infection in Adults

Acute uncomplicated UTI is one of the most common problems for which young women seek medical attention, and it accounts for considerable morbidity and health care costs. Acute cystitis is a superficial infection of the bladder mucosa, whereas pyelonephritis involves tissue invasion of the upper urinary tract. Localization tests suggest that as many as one third of episodes of acute cystitis are associated with silent upper tract involvement. Acute cystitis or pyelonephritis in the adult patient should be considered uncomplicated if the patient is not pregnant or elderly, if there has been no recent instrumentation or antimicrobial treatment, and if there are no known functional or anatomic abnormalities of the genitourinary tract. Most of these infections are caused by E. coli, which are susceptible to many oral antimicrobials. Because of the superficial nature of cystitis, single-dose and 3-day regimens have gained wide acceptance as the preferred methods of treatment. Review of the published data suggests that a 3-day regimen is more effective than a single-dose regimen for all antimicrobials tested. Regimens with trimethoprim-sulfamethoxazole appear to be more effective than those with beta-lactams, regardless of the duration. Acute pyelonephritis does not necessarily imply a complicated infection. Upper tract infection with highly virulent uropathogens in an otherwise healthy woman may be considered an uncomplicated infection. The optimal treatment duration for acute uncomplicated pyelonephritis has not been established, and 14-day regimens are often used. We prefer to use antimicrobials that attain high renal tissue levels, such as trimethoprim-sulfamethoxazole or quinolones, for pyelonephritis. Women with frequently recurring infections can be successfully managed by continuous prophylaxis, either daily or thrice-weekly, by postcoital prophylaxis, or, in compliant patients, by early self-administration of single-dose or 3-day therapy as soon as typical symptoms are noted. Our drug of choice for all these regimens is trimethoprim-sulfamethoxazole. Acute uncomplicated cystitis in adult men is very uncommon, but it is occasionally noted in homosexual men who practice insertive and intercourse or in heterosexual men whose partners have vaginal colonization with E. coli.

The Value of Single-Dose Therapy to Diagnose the Site of Urinary Infection

Several single dose regimens have been shown to cure 90 percent of women with acute cystitis in whom infection is confined to the bladder. About 25 percent of women with acute cystitis and approximately one-half with asymptomatic infection have organisms originating from one or both upper urinary tracts. Effective single dose regimens such as trimethoprim-sulfamethoxazole, amoxicillin, and trimethoprim alone, cure between 40 and 60 percent of upper tract infections in women with renal involvement, who present with acute cystitis or with asymptomatic bacteriuria. Five studies have shown that single dose failure in women with acute cystitis or asymptomatic bacteriuria is a specific predictor of upper tract infection. It is also sensitive (60-80 percent) in predicting upper tract pathology. The evidence to date favours the hypothesis that failure of single dose cure following treatment with an effective single dose regimen in adult women who have asymptomatic bacteriuria or acute cystitis, identifies a subset of women who require further investigation of the urinary tract.

Southwestern Internal Medicine Conference: Prognosis in Pyelonephritis: Promise or Progress?

Prognosis in pyelonephritis, or upper urinary tract infection, is provided. This infection is not responsible for progressive renal disease in young or elderly patients but accounts for frequent febrile episodes in women of all ages and men after the age of 50. Vigorous local immune response develops with the infection, which never succeeds in eradicating bacteria but does limit the infection and provides a diagnostic test: the antibody-coated bacteria test. Emphasis is placed on the need for a localization test for upper tract infection because studies based exclusively on clinical criteria are invalid. Appropriate therapy for mildly ill patients is given with recommendations of combination therapy for severely ill persons. Long-term follow-up is critical because most patients with recurrent infections can be given preventive therapy without subjecting them to needless urologic evaluation.

Vesicoureteral Reflux in the Primate. IV. Infection as Cause of Prolonged High-Grade Reflux

High-grade reflux commonly lasts longer than moderate reflux, which disappears with maturation of the ureterovesical junction. It is known that ureteral function is affected by urinary tract infection from studies in experimental animals, as well as through clinical findings in patients with upper tract infection. Whether infection might affect the ability of the ureter to prolong high-grade reflux was questioned. This observation might explain why high-grade reflux does not disappear as rapidly as moderate reflux in children with recurrent urinary tract infections. Vesicoureteral reflux was produced surgically in combination with bladder neck obstruction using infant monkeys. The reflux thus produced was high grade with ureteral dilation and caliectasis. In the group of animals in which the bladder neck obstruction was relieved surgically, the reflux rapidly disappeared. In the other group, a bladder infection was produced with Escherichia coli at the time of release of the bladder neck obstruction. The reflux lasted significantly longer, an average of 18 months. Therefore, it appears that treatment of urinary tract infection rather than vesicoureteral reflux is the most important therapy.

The Intravenous Pyelogram in Acute Pyelonephritis

In a cohort of 67 otherwise healthy patients with acute pyelonephritis that was severe enough to warrant hospitalization and uroradiography, 8% had a genitourinary abnormality that influenced management. Consequently, over 90% of patients had studies that did not alter their care. In an attempt to identify clinical clues that might increase specificity without compromising sensitivity of the intravenous pyelogram in acute pyelonephritis, only the fever curve was statistically useful. Confined to patients who were febrile through 72 hours of appropriate antibiotic treatment, the yield of urography in demonstrating anomalies of immediate clinical significance rose from 8% to 36%. The likelihood of an acutely important abnormality was also increased fivefold in both diabetic patients and patients with a urinary pathogen other than ampicillin-sensitive Escherichia coli, but small numbers precluded statistical significance. Bacteremia was common (27%), but not helpful other than in confirming the microbiological diagnosis. Nonacute structural abnormalities were present in 43% of the patients, three to nine times more frequently than in reported cases without upper tract infection.

The intravenous pyelogram in acute pyelonephritis

In a cohort of 67 otherwise healthy patients with acute pyelonephritis that was severe enough to warrant hospitalization and uroradiography, 8% had a genitourinary abnormality that influenced management. Consequently, over 90% of patients had studies that did not alter their care. In an attempt to identify clinical clues that might increase specificity without compromising sensitivity of the intravenous pyelogram in acute pyelonephritis, only the fever curve was statistically useful. Confined to patients who were febrile through 72 hours of appropriate antibiotic treatment, the yield of urography in demonstrating anomalies of immediate clinical significance rose from 8% to 36%. The likelihood of an acutely important abnormality was also increased fivefold in both diabetic patients and patients with a urinary pathogen other than ampicillin-sensitive Escherichia coli, but small numbers precluded statistical significance. Bacteremia was common (27%), but not helpful other than in confirming the microbiological diagnosis. Nonacute structural abnormalities were present in 43% of the patients, three to nine times more frequently than in reported cases without upper tract infection.

Can Extracorporeal Shock Wave Lithotripsy Eradicate Persistent Urinary Infection Associated with Infected Stones?

Infected renal stones can be treated by extracorporeal shock wave lithotripsy but it still is not clear whether successful stone fragmentation and the disappearance of all macroscopic stone fragments guarantee eradication of the infection. Therefore, a prospective study was done in 135 patients with renal or upper ureteral stones associated with persistent urinary tract infection. The urinary infection was localized in each patient by bilateral ureteral catheterization. Upper tract infection in the kidney containing the stone was found in 75.6 per cent of the cases. A total of 94 patients completed treatment with extracorporeal shock wave lithotripsy and were followed for 3 to 16 months (mean followup 6.4 months). A marked correlation between the incidence of residual macroscopic stone fragments and the presence of persistent infection was noted. Of the 51 patients who became free of stones 48 (94 per cent) had sterile urine. Only 3 of the 51 patients had persistent infection in the treated kidney despite complete disappearance of the stones. In 45 of the 59 patients with stones smaller than 2cm. (76 per cent) the infection was eradicated, whereas of the 35 with larger stones the urine became sterile in only 13 (37 per cent). We conclude that extracorporeal shock wave lithotripsy can be endorsed for treatment of small infected stones but it is inadequate for treatment of stones larger than 2cm. unless combined with percutaneous nephrolithotripsy or chemical dissolution of the residual infected fragments.

Vesicoureteral Reflux in the Primate. Iv. Infection as Cause of Prolonged High-Grade Reflux

High-grade reflux commonly lasts longer than moderate reflux, which disappears with maturation of the ureterovesical junction. It is known that ureteral function is affected by urinary tract infection from studies in experimental animals, as well as through clinical findings in patients with upper tract infection. Whether infection might affect the ability of the ureter to prolong high-grade reflux was questioned. This observation might explain why high-grade reflux does not disappear as rapidly as moderate reflux in children with recurrent urinary tract infections. Vesicoureteral reflux was produced surgically in combination with bladder neck obstruction using infant monkeys. The reflux thus produced was high grade with ureteral dilation and caliectasis. In the group of animals in which the bladder neck obstruction was relieved surgically, the reflux rapidly disappeared. In the other group, a bladder infection was produced with Escherichia coli at the time of release of the bladder neck obstruction. The reflux lasted significantly longer, an average of 18 months. Therefore, it appears that treatment of urinary tract infection rather than vesicoureteral reflux is the most important therapy.

Urinary lactic acid dehydrogenase activity and the site of urinary tract infections.

A report that elevated urinary lactic acid dehydrogenase (LDH) isoenzyme 5 activity is a reliable tool for separating patients with upper from those with lower urinary tract infections (UTIs) led us to study urinary LDH enzyme activity in girls having bladder washout studies to localize the site of infection. Urinary LDH isoenzyme 5 activity in 64 instances of lower UTI was 16.1 +/- 3.3%, a value not significantly different than that of 18.2 +/- 12.6% found in 26 instances of upper tract infection (t = 0.8726, P = 0.1928). The data show that LDH isoenzyme 5 activity is of no value for localization of the site of a UTI. The data of these studies also showed that urinary LDH enzyme activity clearly separates girls with UTIs from those without infections, but it is unlikely that this finding will be of value in diagnosis or management.

Recurrent Urinary Tract Infection in Adult Women: Diagnosis and Treatment

Recurrent urinary infection may be either relapse or reinfection. The majority of women experiencing recurrent infection have normal genitourinary tracts. For recurrent cystitis, single-dose therapy is optimal and symptomatic episodes are effectively prevented with continuous low-dose antimicrobial prophylaxis. For upper tract infection, or relapse after single dose therapy, two-week therapy is generally adequate. Investigation for abnormalities of the genitourinary tract should be reserved for women who fail to respond to therapy or with relapsing or bacteremic infection.

Single-agent therapy for women with acute polymicrobial therapy pelvic infections

Pathogens that cause acute polymicrobial female pelvic infections usually do not differ from those that compose the normal flora of the lower reproductive tract. Accurate identification of these bacteria is difficult because cultures obtained via the lower tract can easily be contaminated. Although use of a double-lumen catheter-protected brush culture cannot completely eliminate the risk of contamination, it is the least invasive method for obtaining culture material from the upper reproductive tract. Compounding the problem of accurately identifying pathogens that cause acute upper tract infections is the fact that bacteria appear to be present in the upper tracts of asymptomatic women with normal examinations. Because of these problems and because of the polymicrobial nature of these infections, empiric therapy frequently includes more than one antimicrobial agent. Newer, semisynthetic penicillins and cephalosporins have expanded spectrums of in vitro activity against most of the bacteria frequently recovered from pelvic infection sites. Comparative clinical trials have shown these agents to be as effective when used alone as is combination therapy. With few exceptions, empiric monotherapy with one of these newer antimicrobials will be curative for women with acute upper tract infection, will have less potential toxicity, will require less space, materials, and manpower to administer, and will be less expensive.

Microbiological and histopathological findings in acute pelvic inflammatory disease

Upper genital tract infection was investigated in 45 women admitted to hospital for suspected acute pelvic inflammatory disease (PID). Salpingitis was diagnosed by laparoscopy in 30 (67%) women. Histopathological evidence of endometritis was found significantly more often in the 30 women with salpingitis (87%) than in the other 15 women without salpingitis (33%). C. trachomatis or N. gonorrhoeae, or both, were isolated from the upper genital tract in 14 of the 31 women who had both salpingitis and endometritis or endometritis only but in none of the four women who had salpingitis alone and in none of the 10 women who had no evidence of PID. Bacterial vaginosis was associated with histopathological evidence of upper tract infection. Non-chlamydial non-gonococcal organisms were frequently isolated from the upper genital tract. No organisms were isolated from the upper genital tract from 9 of 35 women with laparoscopic or histopathological evidence of PID compared with 7 of 10 women without evidence of PID. C. trachomatis or N. gonorrhoeae in the endometrium was associated with lymphoid follicles comprising transformed lymphocytes, and correlated with the density of plasma cells on biopsy. The microbiological results support the recommendations of broad spectrum antimicrobial therapy for PID.

Urinary tract infection.

Urinary tract infection exists when bacteria are present in urine in the bladder. Significant bacteriuria ( ≥105 organisms/ml of urine) defines the numbers of bacteria in midstream clean voided urine that exceed the numbers usually caused by contamination from the anterior urethra. Urinary tract infections can be categorized anatomically into lower tract infection (i.e. involving the bladder) and upper tract infection (infection in the kidney). Cystitis refers to lower tract infection associated with symptoms of frequency, urgency and/or dysuria. One third of patients with cystitis have asymptomatic upper tract infection. The urethral syndrome refers to symptoms of dysuria, frequency, and/or urgency associated with ≤105 bacteria per ml of urine. One third of patients with this syndrome have lower tract bacterial infection with bacteria in the bladder as demonstrated by suprapubic bladder aspiration. Acute pyelonephritis refers to upper tract infection associated with symptoms of fever and flank pain. Symptoms of lower tract infection frequently accompany pyelonephritis. Most urinary tract infection is asymptomatic, i.e. asymptomatic bacteriuria. One third of patients with asymptomatic bacteriuria havex upper tract infection.

Microelements in the Circulation of Coccidiosis-Infected Chicks

Four-week-old Single Comb White Leghorn male chicks were inoculated with either Eimeria acervulina, E. necatrix, E. brunetti, E. tenella, or left uninfected. On Days 1, 3, 5, 6, 7, 8, 9, 10, 14, 21, 28, and 35 after inoculation, blood was removed from five birds in each group; content of copper, zinc, and iron in plasma and total iron-binding capacity were determined. Copper content in plasma was increased during the acute phase of the infections by lower intestinal tract (E. brunetti, E. tenella) infections but not by upper tract (E. acervulina, E. necatrix) infections. Zinc content in plasma was decreased by E. acervulina and E. necatrix infections on the 7th day and was increased by E. acervulina, E. brunetti, and E. tenella infections on the 9th or 10th days. Iron content in plasma was decreased during the acute phase (Days 5 to 7) of E. acervulina, E. brunetti, and E. tenella infections. Total iron-binding capacity was decreased by acute phase E. acervulina and E. brunetti infections. Eimeria tenella infections increased total iron-binding capacity during both the acute and early recovery phases. Plasma content of all components returned to normal by the latter part of the recovery phase of the infections and remained so thereafter. Plasma trace mineral content appeared to be influenced by mineral absorption effects, by hemorrhaging, and perhaps by invasion of the bloodstream by gut bacteria as a result of mucosal damage. In upper tract infections, mineral content of plasma more closely paralleled that expected from previously reported mineral absorptive patterns, while the pattern of plasma mineral content seen in lower tract infections more nearly paralleled those expected from reported effects of bacterial invasion of the bloodstream.

Complications and Treatment of Urinary Tract Infections During Pregnancy

Bacteriuria during pregnancy may result in serious complications, including development of acute pyelonephritis in the third trimester and premature labor. Because uninfected women commonly experience symptoms associated with urinary tract infections and many bacteriuric women are asymptomatic, all pregnant women should be screened by quantitative urine cultures. The goal of antimicrobial therapy is complete elimination of bacteria from the urinary tract. Major indications for complete urologic evaluation are failure of a patient with signs of acute upper-tract infection to improve on appropriate treatment and bacterial persistence after initial sterilization of the urine. Either problem may require surgical intervention.

Relationships Between Human Blood Groups, Bacterial Pathogens, and Urinary Tract Infections

Blood groups of 137 patients with acute pyelonephritis and chronic upper tract infection, cystitis, and asymptomatic bacteriuria were compared with those of a normal uninfected control population. In addition, the identified uropathogens were categorized according to the patient's blood group. There was a significant association between the diagnosis of chronic upper tract infection and blood group B as compared with controls (p = less than 0.05, chi 2). Analysis of the bacterial isolates showed that more patients with blood group B had infections with Pseudomonas sp., Klebsiella pneumoniae, and Proteus sp. than was expected; and fewer patients with blood group A had infections with Pseudomonas than predicted (p = less than 0.05, chi 2). There was an increased number of patients in blood group AB with infections caused by Escherichia coli and Klebsiella pneumoniae. These results suggest that an individual's blood group may be a significant factor in the host-response to bacterial invasion and influence the development of infection with certain gram-negative bacilli.

Ureteral Infection Stones

We report a case of recurrent urinary tract infections owing to culture proved ureteral infection stones. Although ureteral catheterization studies unilaterally localized the infection to the upper urinary tract, the direct immunofluorescence antibody test indicative of upper tract infection was negative. The patient was cured of persistent urinary tract infection by antibiotics, ureterolithotomy, resection of the stenotic ureteral segment and ureteroureterostomy

Macroelements in the Circulation of Coccidiosis-Infected Chicks

Four-week-old Single Comb White Leghorn (SCWL) chicks were inoculated with either Eimeria acervulina, E. necatrix, E. brunetti, E. tenella, or left uninfected. On the 1st, 3rd, 5th, 6th, 7th, 8th, 9th, 10th, 14th, 21st, 28th, and 35th days after inoculation, blood was removed from five birds in each group, and the content of calcium, magnesium, sodium, potassium, hemoglobin, erythrocytes, and packed cell volumes were determined. Hemoglobin, erythrocyte concentrations, and hematocrits all decreased during the acute phase of the infections and returned to normal during recovery. Plasma calcium concentrations were significantly decreased by the upper intestinal tract infections, but decreases were smaller in lower tract infections. Plasma magnesium was decreased and then increased by lower tract infections, but upper tract infections had variable effects. In contrast to earlier reports, acute phase E. acervulina, E. brunetti, and E. tenella infections decreased sodium plasma concentrations. Plasma potassium concentrations were variable, but increases were associated with the induction phases of E. necatrix and E. brunetti infections.

Urinary Tract Infections in Childhood: An Update

Although controversies remain regarding the definition, diagnosis, and management of urinary tract infections, such infections can pose a major risk to a child's well-being. Bacteriuria or recurrent urinary tract infections often pose difficult management problems. Symptomatic and asymptomatic bacteriuria during infancy are generally characterized by a benign outcome. In some children repeated episodes and, possibly, renal scarring result. The prognosis in young boys may be guarded if neonatal bacteriuria, with or without symptoms, occurs in the presence of anatomic defects. Although a variety of pathogens have been identified as causing urinary tract infections, Enterobacteriaceae are usually the cause of initial uncomplicated lower tract infections. Accepted therapy for such infections is reviewed, as are the combination therapies used for hospitalized patients with upper tract infections. An investigation of piperacillin, a new, extended-spectrum acylaminopenicillin, raises the hope that it may provide effective monotherapy for upper tract infections. The criteria for selecting patients who require radiologic evaluation in the management of urinary tract infections are reviewed.

An overview: evaluation of cefonicid in infections of the urinary tract, lower respiratory tract, and skin and soft tissue.

Infections of the urinary and lower respiratory tracts and of skin and soft tissue constitute a large proportion of infections requiring antimicrobial therapy. For many antimicrobial agents, one dose will cure lower urinary tract infection. In contrast, relapse of upper tract infection is common even after two weeks of treatment. In comparing the efficacy of antimicrobial agents in urinary infection, it is critical that patients assigned to different agents be equivalent. The questions about cefonicid in urinary infection that must be addressed concern (1) adverse effects and tolerability, (2) cost, and (3) rationale for the use of a parenteral preparation in uncomplicated urinary infection. In lower respiratory tract infections, therapeutic efficacy is difficult to evaluate primarily because of the difficulty in determining the causative role of the organisms isolated from sputum. The inclusion of information from gram-stained preparations reduces the diagnostic error. As far as cefonicid in treatment of pneumonia is concerned, the high serum protein binding reported and the relatively high minimal inhibitory concentrations for gram-positive cocci must be addressed. In skin and soft-tissue infections, therapeutic efficacy is difficult to evaluate because of the lack of isolates and the self-limited nature of many cutaneous infections.