Mycoplasmas in human pyelonephritis: demonstration of antibodies in serum and urine.

This study was carried out to elucidate by serological examination the etiological significance of mycoplasmas isolated from the upper urinary tract of patients with pyelonephritis. The occurrence of antibodies in patients with acute pyelonephritis, chronic pyelonephritis with or without exacerbation, or noninfectious urinary tract disease was compared by the indirect hemagglutination method. Antibody response was demonstrated significantly more often in patients yielding growth of Mycoplasma hominis from the upper urinary tract than in patients not yielding growth. Antibodies against M. hominis were demonstrated in ureteric and bladder urine from three patients with acute pyelonephritis and from one patient with exacerbation of chronic pyelonephritis. M. hominis was isolated from the upper urinary tract of all four patients. Urine antibodies could not be demonstrated in any other cases. Thus, it seems highly possible that M. hominis may play a role in pyelonephritis of humans. The investigations did not disclose a similar role for Ureaplasma urealyticum.     

Diagnosis of Mycoplasma hominis pyelonephritis by demonstration of antibodies in urine.

To evaluate the diagnostic significance of the demonstration in urine of antibodies to Mycoplasma hominis, 1,000 samples of urine with more than 5 leukocytes per high-power field were serologically investigated by indirect hemagglutination, using glutaraldehyde-fixed erythrocytes coated with M. hominis antigen. The samples were collected from 702 patients. Antibodies were demonstrated in the urine of nine patients, all of whom had signs of acute attack of pyelonephritis. In seven of these patients, characterized by mild or moderate clinical signs and absence of lower urinary tract symptoms, bacterial causes were not observed, whereas M. hominis organisms were isolated from the upper urinary tract in most cases and from the bladder urine in all cases. In two patients, characterized by severe clinical signs and presence of lower urinary tract symptoms, both M. hominis and bacteria were isolated from the upper urinary tract and ballder urine. The demonstration of antibodies to M. hominis in urine is of high diagnostic value as they were only observed in patients in whom M. hominis infection in the upper urinary tract was evident or likely and only in the presence of clinical signs of acute attacks of pyelonephritis.     

Escherichia coli K5 antigen in relation to various infections and in healthy individuals.

A phage specific for Escherichia coli K5 antigen was used to determine the frequency of K5 in strains of E. coli isolated from cases of sepsis, meningitis, and urinary tract infection (pyelonephritis, cystitis, and asymptomatic bacteriuria), as well as from fecal samples of healthy subjects. Although entirely absent from meningitic strains, K5 was found to be one of the most common E. coli capsular antigens, especially in strains causing sepsis. K5 was less common in the fecal strains of healthy subjects than in strains causing various urinary tract infections, between which there was no significant difference in its frequency. Thus, even if K5 is a less important antigen than K1 in the etiology of acute pyelonephritis or acute meningitis, as the fifth most commonly occurring K antigen in E. coli strains causing urinary tract infection it should be included as a component in any K antigen-based vaccine against acute pyelonephritis.     

Physicochemical surface properties of Escherichia coli strains isolated from different types of urinary tract infections.

Escherichia coli strains isolated from three groups of patients with urinary tract infections, such as acute pyelonephritis, acute cystitis, and asymptomatic bacteriuria, were analyzed with respect to their physicochemical surface properties by means of polymer two-phase partitioning in dextran-polyethylene glycol systems and hydrophobic interaction chromatography on Octyl-Sepharose. Strains causing acute pyelonephritis constituted a homogenous group which, depending on the growth conditions, demonstrated smooth-type lipopolysaccharide, elevated negative charge, and liability to hydrophobic interaction, whereas strains isolated from acute cystitis and asymptomatic bacteriuria showed a more heterogenous pattern.     

Adhesion, hemagglutination, and virulence of Escherichia coli causing urinary tract infections.

The capacity of 453 Escherichia coli strains to agglutinate erythrocytes and yeast cells and to attach to human urinary tract epithelial cells was tested. The strains were isolated from the urine of patients with acute pyelonephritis, acute cystitis, or asymptomatic bacteriuria and from the stools of healthy school children. Three main patterns of hemagglutination were found: (i) mannose-resistant agglutination of human erythrocytes alone or simultaneously with mannose-sensitive agglutination of guinea pig erythrocytes; (ii) only mannose-sensitive agglutination of guinea pig and other erythrocytes; and (iii) no agglutination. Strains with mannose-resistant agglutination of human erythrocytes alone or in combination with mannose-sensitive hemagglutination attached in high numbers to human urinary tract epithelial cells. Bacteria inducing only mannose-sensitive hemagglutination attached in low numbers, and non-agglutinating strains did not bind to the urinary tract epithelial cells. The bacterial surface antigen(s) mediating mannose-resistant hemagglutination of human erythrocytes and attachment to human urinary tract epithelial cells may be one factor selecting for E. coli from among the fecal flora which infect the urinary tract. The highest proportion of strains with this property was found among acute pyelonephritis isolates (77%), and the lowest proportion of strains with this property was found among normal fecal E. coli (16%).     

Diagnostic potential of urinary enzymes and beta 2-microglobulin in acute urinary tract infection

Urinary excretions of beta 2-microglobulin (beta 2M), N-acetyl-beta-D-glucosaminidase (NAG), alanine aminopeptidase, beta-glucuronidase, acid and neutral alpha-glucosidase as indicators of proximal tubular dysfunction were measured in patients with acute upper and lower urinary tract infection (UTI) and fever of non-renal origin. The sensitivity of beta 2M was 67% and of NAG 49% as assessed in more than 100 episodes of acute pyelonephritis. Combined use of beta 2M and NAG increased the sensitivity to 75%. The degree of beta 2-microglobulinuria and enzymuria was comparable in patients with acute pyelonephritis and fever due to non-renal infections. The excretion of beta 2M and the various enzymes was too variable and unpredictable in individual cases to be useful as diagnostic indicator. In localizing an acute UTI, tests for proximal tubular dysfunction seem to be of no more clinical value than properly measured body temperature.     

Urinary lactate dehydrogenase isoenzyme analysis in adult population

This investigation was a systemic study on an adult population of urinary lactate dehydrogenase (LDH) isoenzyme analysis for the distinction between upper and lower urinary tract infections. The study included 160 urine samples from patients and healthy individuals. On the basis of clinical symptoms, urinary bacterial colony counts, renal function tests and radiologic findings, the adults were divided into pyelonephritis group, cystitis group, pelvic lesion group, and control group. This technique correctly identified 23 of 26 patients with pyelonephritis by the presence of elevated LDH-V (over 10 percent) and all of 12 patients with cystitis by the presence of elevated LDH-I (over 60 relative units) but low LDH-V (below 10 percent or lower than LDH-I). In the pelvic group, the results of eight patients were consistent with cystitis and four with pyelonephritis. Our study confirms the sensitivity and specificity of the LDH isoenzyme technique for the differential diagnosis of urinary tract infection on adult patients and is consistent with previous studies on pediatric patients. However, one should be cautious to interpret the results of LDH isoenzymogram before extra-urinary tract lesions are excluded.     

Virulence of Escherichia coli in relation to host factors in women with symptomatic urinary tract infection.

The relationship between bacterial characteristics and the severity of urinary tract infection in adults has not been clarified. In this study, Escherichia coli strains (n = 178) were prospectively collected from women with community-acquired urinary tract infection. The isolates were identified by O:K:H serotype and characterized for adherence, hemolysin production, and serum bactericidal resistance. The patients had acute pyelonephritis with or without complicating factors and acute cystitis. Nine serotypes (O1:K1:H7, O1:K1:H-, O2:K1:H-, O4:K12:H1, O7:K1:H-, O9:K34:H-, O16:K1:H6, O16:K1:H-, and O75:K5:H-) comprised 65% of the strains in uncomplicated pyelonephritis, but were significantly less often encountered in complicated pyelonephritis or cystitis. Adherence was the single property most characteristic of the pyelonephritogenic clones. Adhesins specifically recognizing Gal alpha 1----4Gal beta-containing receptors occurred in 80% of strains in uncomplicated pyelonephritis, in 50% of strains in complicated infections, and in 37% of cystitis strains. Hemolysin production and serum resistance did not correlate with any disease pattern. Advanced age did not seem to reduce the selection of virulent E. coli to cause pyelonephritis. These results demonstrate in women a relationship between E. coli virulence and the severity of urinary tract infection analogous to that previously observed in pediatric populations and also illustrate the balance between host resistance and bacterial virulence in the urinary tract.     

Have Ureaplasma urealyticum and Mycoplasma hominis infections any significant effect on women fertility?

Ureaplasma urealyticum and Mycoplasma hominis are known as sexually transmitted agents. U. urealyticum and M. hominis jeopardize male fertility. However, it is unclear whether these infections significantly contribute to female infertility. In this controlled-study we aimed to establish whether M. hominis and U. urealyticum are risk factors for female fertility and prevalence of infection from these agents in patients attending our infertility clinic. Total 96 married women enrolled in this prospective study; the infertile (study) group consisted of 50 women and fertile (control) group comprised 46 women. The patients were searched about the presence of U. urealyticum and M. hominis by a micro-liquid culture method. The samples were collected from endocervical area with a dacron swab. 28 of 50 (56%) and 18 of 46 (39%) women were evaluated as positive for U. urealyticum culture in the study and control groups respectively. M. hominis was cultured from 4 of 50 (8%) women in the study group as no positive result in controls. There were no statistically significant differences between the groups for both agents (p>0.05), but the higher prevalence of U. urealyticum in infertile women gives emphasis to evaluate these agents in patients that have no any other etiological factor for infertility.     

High prevalence of upper urinary tract involvement detected by <Superscript>111</Superscript>indium-oxine leukocyte scintigraphy in patients with candiduria

The purpose of this investigation was to assess the prevalence of upper urinary tract involvement in patients with candiduria by means of ¹¹¹indium-oxine-labeled leukocyte scintigraphy. An observational cohort study of patients with confirmed candiduria was conducted in an acute-care teaching hospital in Spain from March 2006 through February 2009. An ¹¹¹In-labeled leukocyte scan was performed in order to assess the upper urinary tract involvement. A series of non-matched patients without candiduria nor bacteriuria undergoing scintigraphy to exclude infections in other sites than the urinary tract was also studied. Demographics, baseline illness, and clinical data were recorded. Candiduria was detected in 428 patients, and scintigraphy was performed in 35 of these patients. Twenty-nine patients without candiduria nor bacteriuria were also studied. Positive renal scintigraphy was documented in 24 (68%) patients with confirmed candiduria and in 3 (10%) patients without candiduria (p < 0.005). Renal uptake was not associated with a higher mortality nor with re-admissions. Subclinical pyelonephritis could be more frequent in patients with candiduria than it has been previously considered.     

CRP检测在妊娠合并急性泌尿系感染中作用探讨

目的探讨CRP在妊娠合并急性泌尿系感染中的作用。方法检测2005年6月～2006年6月32例妊娠合并急性泌尿系感染病例的CRP。其中妊娠合并急性肾孟肾炎和妊娠合并急性膀胱炎各16例。选择同期16例健康孕妇作对照组，采用免疫比浊法检测CRP（用Twbox Plus检测仪）。结果妊娠合并急性肾孟肾炎治疗前发热天数与CRP值正相关（r^2=0．528 P＜0．01）。CRP为40mg／L时，诊断急性肾孟肾炎敏感性为0．92，特异性为0．97。妊娠合并急性肾孟肾炎CRP平均值为78mg／L，急性膀胱炎组CRP值仅为10mg／L，正常孕妇CRP平均值为6mg／L。急性肾孟肾炎组明显高于急性膀胱炎组，差异有极显著性（P＜0．01）。结论CRP是妊娠合并急性肾孟肾炎病情观察的指标，CRP值与患者治疗前发热时间长短有关。在鉴别妊娠合并急性肾孟肾炎和急性膀胱炎中，CRP是一个特异性和敏感性较好的指标。     

Serological response to P-fimbriae ofEscherichia coli in patients with urinary tract infections

The antibody response to P-fimbriae ofEscherichia coli in patients with upper urinary tract infections was investigated. In the sera of patients with pyelonephritis obtained at the initial visit to hospital (3 to 7 days after the onset of symptoms), a high incidence of antibodies to P-fimbriae was detected (12 out of 14 patients). P-fimbriatedEscherichia coli strains were isolated from urine samples in all of these antibody-positive patients. Antibodies detected by ELISA using purified antigen were essentially IgG and specifically recognized P-fimbriae. These antibodies inhibited completely, or in some cases partially, mannose-resistant hemagglutination with P-fimbriatedEscherichia coli.     

Attachment of Proteus mirabilis to human urinary sediment epithelial cells in vitro is different from that of Escherichia coli.

The in vitro attachment of 335 Proteus mirabilis strains from various human sources to human urinary tract epithelial cells was measured. No significant difference in adhesive capacity was found between P. mirabilis strains isolated from the blood of 89 patients with bacteremia, the stools of 36 healthy subjects and 56 patients with diarrhea, and the urine of 62 adults and 92 children with bacteriuria. High mean adhesion values were observed in all groups. The P. mirabilis strains attached only to squamous cells and not to transitional epithelial cells, whereas most of the Escherichia coli strains tested attached to both cell types; strains from patients with acute pyelonephritis attached more often than those from patients with acute cystitis or asymptomatic bacteriuria. The attachment of P. mirabilis to squamous epithelial cells was high about day 15 of the menstrual cycle of the epithelial cell donor, but low at the beginning and the end of the cycle. In contrast, the attachment of E. coli to squamous and transitional epithelial cells did not vary significantly with the menstrual cycle of the cell donor. Differences in adhesion characteristics of E. coli and P. mirabilis may relate to the differences in clinical appearance of urinary tract infections produced by the two organisms.     

In vitro activity of nitroxoline on urogenital mycoplasmas

The product nitroxoline was studied in vitro for its activity towards Ureaplasma urealyticum and Mycoplasma hominis. In view of the low MIC values obtained, it seems nitroxoline could be used in the treatment of urinary infections. It is bactericidal, and should not produce resistant strains.     

Prevalence and characterization of uropathogenic Escherichia coli producing cytotoxic necrotizing factor type 1 (CNF1) in the center of Tunisia]

During a three-year survey of the prevalence in central Tunisia of Escherichia coli producing CNF1 toxin (NTEC), 716 samples have been investigated by PCR for cnf1 gene. All samples were isolated from urine of adult and children patients presenting significant bacteriuria (> 10(5) colony-forming units/mL), independently of the severity of the clinical presentation; 328 strains were found harboring cnf1 gene, they were distributed into three clinical categories: 219 (66.76%) from patients with symptomatic bacteriuria, 76 (23.17%) from patients with uncomplicated cystitis and 33 (10.06%) from patients with acute pyelonephritis and complicated urinary tract infections. 98.78% (324) of CNF1 strains presented hemolytic activity. All 328 CNF1 strains harbored both sfa and pap genes and expressed MRHA activity. They belonged to 16 different serotypes. The most common serotypes, in order of frequency, were O6 (25.91%), O4 (17.98%), O2 (12.5%), O75 (9.14%), O78 (8.35%), and O83 (3.65%). Two strains (0.6%) were O168; a serotype shown to be associated to CNF2 producing bovine strains. The frequency of uropathogenic CNF1 strains in center Tunisia was about 45.81% and increased from 26.08% in 1998 to 58.16% in 2000. We showed that E. coli producing cytotoxic necrotizing factor (CNF1) was implicated in urinary tract infections in center Tunisia but no difference was shown between strains isolated from patients with complicated or uncomplicated urinary tract infections. The presence of CNF1 toxin with various associated virulence factors seemed to increase the risk for severe forms of urinary tract infections.     

Bacterial and host determinants of renal scarring

This review summarizes recent work examining the interaction between host and parasite in recurrent urinary tract infection (UTI) and renal scarring. Virulence in uropathogenic E. coli has been defined by the severity of acute disease. Isolates from patients with acute pyelonephritic strains differ from those causing asymptomatic bacteriuria by multiple traits which contribute to virulence, and which are coexpressed in a non-random manner. The single marker most characteristic for the pyelonephritogenic clones is bacterial adherence to uroepithelial cells binding specifically to the disaccaride Gal alpha 1-4 Gal beta within the globoseries of glycolipids. The notion that the most severe consequence of acute pyelonephritis, i.e. renal scarring, was caused by the most virulent clones, was contradicted by comparison of pyelonephritic strains isolated from children with and without scarring. The virulent clones were significantly less frequent in patients with renal scarring (22%) than in patients with recurrent pyelonephritis not developing renal scars (62%). In view of the unexpected inverse association of bacterial virulence with renal scarring lack of Gal alpha 1-4 Gal beta binding capacity of E. coli strains was found to predict the risk for renal scarring among boys with first-time acute pyelonephritis. Vesicoureteric reflux (VUR) is widely accepted as a host determinant of susceptibility to pyelonephritis and renal scarring. In our study the frequency of renal scarring was 57% among girls with VUR as compared to 8% of those without. The reflux alone did however, not explain the selection of bacteria of low virulence. Individuals prone to UTI and renal scarring were found to be a genetically selected subgroup of the general population. A correlation between P1 blood group phenotype and susceptibility to UTI and between blood group non-secretor state and renal scarring was found. The mechanisms behind these relationships need to be defined. The bacterial and host parameters combined indicate that host parameters are essential for the tendency to develop renal scarring after acute pyelonephritis.     

In vitro sensitivity to antibiotics in 178 strains of genital mycoplasma isolated from gynecology consultants in Dakar

The susceptibility to antibiotics of 144 strains of Ureaplasma urealyticum and 34 strains of Mycoplasma hominis isolated in Dakar, Senegal, was determinated by MIC determination in a medium. Doxycyclin and minocyclin are active on more than 90% of the strains of U. urealyticum, and more than 80% of M. hominis strains. Over 93% of U. urealyticum strains are susceptible to all the macrolids and apparented tested (erythromycin, pristinamycin, josamycin), but the activity of lincomycin, pristinamycin and josamycin on M. hominis was found only for 70% of the strains. Fluoroquinolones, once adequately studied, could turn out to be a useful alternative in therapeutics.     

Is resistance to novobiocin a reliable test for confirmation of the identification of Staphylococcus saprophyticus?

Staphylococcus saprophyticus, a coagulase-negative staphylococcus (CNS), causes acute urinary tract infection predominantly in young women (15-30 years). In the clinical microbiology laboratory identification and differentiation of S. saprophyticus from other CNS usually depends solely upon the demonstration of resistance to the antimicrobial agent novobiocin. Phenotypic characteristics of 36 novobiocin-resistant CNS isolated from the urine of patients with acute urinary tract infections were further analysed and the homogeneity of the isolates assessed. The organisms were speciated by the API STAPH identification system. Twenty-one isolates were S. saprophyticus (p greater than or equal to 97%), and there was one strain each of S. epidermidis, S. hominis and S. simulans (p greater than or equal to 97%). Of the remainder, three isolates were unidentifiable and a further nine had the characteristics associated with more than one species of CNS. Additional tests, including carbohydrate fermentation, antibiotic sensitivity and fluorogenic substrate utilisation, were performed on all isolates. Computer analysis of the results confirmed that testing for resistance to novobiocin selects a heterogeneous group of CNS composed of several different species.     

Urinary Immunoglobulins in Healthy Individuals and Children with Acute Pyelonephritis

Urine samples obtained from children with acute pyelonephritis and from healthy children and adults were analysed with regard to the molecular form and specific antibody activity of urinary immunoglobulins. The urinary IgA and IgG levels were quantified in unconcentrated urine by radioimmunoassay. The children with urinary tract infection had significantly higher levels of IgG and IgA than age-matched controls but not higher than healthy adults. After tenfold concentration, the urine was fractionated on an Ultrogel AcA 22 column, and the IgA, secretory IgA, and IgG in the fractions were determined by radioimmunoassay. IgA in urine from healthy adults was predominantly represented by polymeric IgA linked to secretory component; small quantities of monomeric IgA were also present. IgG eluted in the position of the serum standard. Increased proportions of IgG and monomeric IgA were found in the infected patients. Specific antibody activity of the IgG and IgA classes to antigens of the infecting Escherichia coli strain was detected in whole and in fractionated urine from children with acute pyelonephritis. The specific antibody activity in healthy adults and children was low.     

Comparison of Escherichia coli Strains Recovered from Human Cystitis and Pyelonephritis Infections in Transurethrally Challenged Mice

Urinary tract infection, most frequently caused by Escherichia coli, is one of the most common bacterial infections in humans. A vast amount of literature regarding the mechanisms through which E. coli induces pyelonephritis has accumulated. Although cystitis accounts for 95% of visits to physicians for symptoms of urinary tract infections, few in vivo studies have investigated possible differences between E. coli recovered from patients with clinical symptoms of cystitis and that from patients with symptoms of pyelonephritis. Epidemiological studies indicate that cystitis-associated strains appear to differ from pyelonephritis-associated strains in elaboration of some putative virulence factors. With transurethrally challenged mice we studied possible differences using three each of the most virulent pyelonephritis and cystitis E. coli strains in our collection. The results indicate that cystitis strains colonize the bladder more rapidly than do pyelonephritis strains, while the rates of kidney colonization are similar. Cystitis strains colonize the bladder in higher numbers, induce more pronounced histologic changes in the bladder, and are more rapidly eliminated from the mouse urinary tract than pyelonephritis strains. These results provide evidence that cystitis strains differ from pyelonephritis strains in this model, that this model is useful for the study of the uropathogenicity of cystitis strains, and that it would be unwise to use pyelonephritis strains to study putative virulence factors important in the development of cystitis.