La infección urinaria y su prevención / Urinary Tract Infections and Their Prevention

Contexto: En este artículo se revisan diferentes aspectos acerca de la prevención de las infecciones del tracto urinario que incluyen: la confirmación de la existencia de dichas infecciones, la aplicación de medidas higiénico-dietéticas, la profilaxis antibacteriana-preferentemente la toma de una única dosis nocturna diaria oral de un antibiótico o quimioterápico con elevada excreción urinaria y buena tolerancia-, la administración de vacunas elaboradas con Escherichiacoli y otros bacilos gramnegativos completos con fracciones inmunoestimulantes o fimbrias tipo 1 de E. coli por vías parenteral u oral. Objetivo: Revisión de las nuevas medidas de prevención de las infecciones del tracto urinario. Adquisición y síntesis de evidencia: Se revisan diferentes aspectos microbiológicos, la fisiopatología y los factores de virulencia de E. coli uropatógenos productores de fimbrias de tipos 1y P. Se analiza la relación entre los grupos sanguíneos y la infección del tracto urinario en los individuos secretores y no secretores. Conclusiones: El uso de vacunas inactivadas con fenol y administradas por vía mucosa, el empleode inhibidores de la adherencia y de la formación de biopelículas bacterianas y el uso de estimuladores del adenosín-monofosfato cíclico se presentan como nuevas medidas preventivas de la infección urinaria, particularmente para el grupo de mayor incidencia, representado por las mujeres entre la pubertad y la menopausia (AU)

Context: This article reviews diverse aspects of the prevention of urinary tract infections, including confirmation of the diagnosis, application of hygiene and dietary measures, antibacterial prophylaxis (preferably consisting of a single nocturnal oral dose per day of an antibiotic or drug with high urinary excretion and good tolerance), and administration of vaccines made with Escherichia coli and other Gram-negative bacilli, consisting of immunostimulating fractions of E. coli strains or E. coli type-1 fimbriae administered through the parenteral or oral route. Objective: We aimed to review the new preventive measures against urinary tract infections. Acquisition and synthesis of evidence: We reviewed various microbiological aspects, as well as the physiopathology and virulence factors of uropathogenic E. coli strains expressing type-1 and P fimbriae. The association between blood groups and urinary tract infections in blood group antigen-secretors and non secretors was analyzed. Conclusions: New preventive measures against urinary tract infection consist of the use of phenol-inactivated vaccines administered via the mucosal route, inhibitors of bacterial adherence and biofilm formation and cyclic adenosine monophosphate stimulators, especially in women aged between puberty and menopause, who show the highest incidence of these infections (AU)

[Urinary tract infections and their prevention]. / La infección urinaria y su prevención.

CONTEXT: This article reviews diverse aspects of the prevention of urinary tract infections, including confirmation of the diagnosis, application of hygiene and dietary measures, antibacterial prophylaxis (preferably consisting of a single nocturnal oral dose per day of an antibiotic or drug with high urinary excretion and good tolerance), and administration of vaccines made with Escherichia coli and other Gram-negative bacilli, consisting of immunostimulating fractions of E. coli strains or E. coli type-1 fimbriae administered through the parenteral or oral route. OBJECTIVE: We aimed to review the new preventive measures against urinary tract infections. ACQUISITION AND SYNTHESIS OF EVIDENCE: We reviewed various microbiological aspects, as well as the physiopathology and virulence factors of uropathogenic E. coli strains expressing type-1 and P fimbriae. The association between blood groups and urinary tract infections in blood group antigen-secretors and nonsecretors was analyzed. CONCLUSIONS: New preventive measures against urinary tract infection consist of the use of phenol-inactivated vaccines administered via the mucosal route, inhibitors of bacterial adherence and biofilm formation and cyclic adenosine monophosphate stimulators, especially in women aged between puberty and menopause, who show the highest incidence of these infections.

Modification of stool's water content in constipated infants: management with an adapted infant formula.

BACKGROUND: Constipation is a common occurrence in formula-fed infants. The aim of this preliminary study was to evaluate the impact of a formula with high levels of lactose and magnesium, in compliance with the official regulations, on stool water content, as well as a parental assessment of constipation. MATERIALS AND METHODS: Thirty healthy term-born, formula-fed infants, aged 4-10 weeks, with functional constipation were included. All infants were full-term and fed standard formula. Exclusion criteria were preterm and/or low birth weight, organic constipation, being breast fed or fed a formula specially designed to treat constipation. Stool composition was measured by near-infrared reflectance analysis (NIRA) and parents answered questions about crying associated with defecation and stool consistency at baseline and after two weeks of the adapted formula. RESULTS: After 2 weeks of the adapted formula, stool water content increased from 71 +/- 8.1% to 84 +/- 5.9%, (p < 0.02). There was no significant change in the stool's fat, protein or carbohydrate content. Parental impressions of constipation were improved with the decrease in stool hardness (100% with hard stools at baseline, 10% after 2 weeks), pain with defecation (90% at baseline, 10% after 2 weeks), and the requirement for rectal stimulation to achieve defecation (70% at baseline, 30% after 2 weeks, p < 0.001 for all three indicators). CONCLUSIONS: This preliminary study suggests that an adapted formula with high levels of lactose and magnesium increases stool water content and improves symptoms of constipation in term-born, formula-fed infants. A larger randomized placebo-controlled trial is indicated.

Extraintestinal infection due to Hafnia alvei.

The aim of this study was to establish the clinical features of extraintestinal infections caused by Hafnia alvei. Over a 5-year period (1994-1998), data were collected regarding inpatients (n = 8) with nosocomial (n = 5) or community-acquired (n = 3) infections caused by Hafnia alvei. The mean age of the patients was 47 +/- 21 years. Three patients had hospital-acquired urinary tract infections. Hafnia alvei also caused community-acquired cholangitis, cholecystitis, appendicitis, psoas abscess and prosthetic endocarditis. Hafnia alvei was susceptible to amoxicillin/clavulanic acid and to first-generation cephalosporins in two cases. Susceptibility to aminoglycosides, imipenem, cotrimoxazole, ciprofloxacin, piperacillin and cefotaxime was very good (8/8). Four patients required invasive treatment.

[Should cefminox substitute cefoxitin in infectionscaused by bacteria susceptible to both drugs?] / ¿Debe sustituir cefminox a cefoxitinaen en las infecciones por bacterias sensibles a ambos?

We studied the in vitro activity of cefminox (MIC by agar dilution) and cefoxitin against 477 facultative Gram-positive and Gram-negative isolates which were recovered from clinical specimens and identified by standard methods. Cefminox has proved to be 4-16 times more active than cefoxitin against enteric Gram-negative bacilli commonly involved in cholecystitis, secondary peritonitis, intraabdominal abscesses and gynecological infections. On the contrary, cefoxitin has proved to be four times more active against Gram-positive cocci. Both have been ineffective against Enterobacter spp., Pseudomonas aeruginosa and Acinetobacter spp. The microbiological activity and pharmacokinetic parameters of cefminox make it one of the first choice treatments for community-acquired intraabdominal and pelvic infections with the presence of anaerobes.

[Relationship between antimicrobial susceptibility and virulence factors in Helicobacter pylori clinical isolates] / Relación entre sensibilidad antibióticay factores de virulencia en aislamientos clínicosde Helicobacter pylori.

The aim of this study was to determine the relationship between the antibiotic susceptibility and different virulence factors among Helicobacter pylori clinical isolates. One hundred and forty-five strains were isolated from biopsy cultures obtained from adult patients. Antimicrobial susceptibility to amoxicillin, clarithromycin, metronidazole and tetracycline were tested using an agar dilution method. cagA and iceA genes and s1 and s2 alleles of vacA were studied by polymerase chain reaction. A group of patients had been previously treated for H. pylori infection. We found a resistance rate of 28.7% and 16.5% to metronidazole and clarithromycin, respectively. We did not find any resistance to amoxicillin or tetracycline. The cagA gene and s1 allele were detected in 86.3% and 65.2% of the strains. One hundred and two (71.3%) strains were iceA+. cagA+ strains showed lower percentages of resistance to antibiotics, as did vacA s1 and iceA+ strains. The role of lower rates of resistance to clarithromycin and metronidazole in more virulent H. pylori strains may have favorable effects in their eradication in patients infected with these strains.

[Should cefminox substitute cefoxitin in infections caused by bacteria susceptible to both drugs?]. / Debe sustituir cefminox a cefoxitinaen en las infecciones por bacterias sensibles a ambos?

We studied the in vitro activity of cefminox (MIC by agar dilution) and cefoxitin against 477 facultative Gram-positive and Gram-negative isolates which were recovered from clinical specimens and identified by standard methods. Cefminox has proved to be 4-16 times more active than cefoxitin against enteric Gram-negative bacilli commonly involved in cholecystitis, secondary peritonitis, intraabdominal abscesses and gynecological infections. On the contrary, cefoxitin has proved to be four times more active against Gram-positive cocci. Both have been ineffective against Enterobacter spp., Pseudomonas aeruginosa and Acinetobacter spp. The microbiological activity and pharmacokinetic parameters of cefminox make it one of the first choice treatments for community-acquired intraabdominal and pelvic infections with the presence of anaerobes.

[Relationship between antimicrobial susceptibility and virulence factors in Helicobacter pylori clinical isolates]. / Relación entre sensibilidad antibióticay factores de virulencia en aislamientos clínicos de Helicobacter pylori.

The aim of this study was to determine the relationship between the antibiotic susceptibility and different virulence factors among Helicobacter pylori clinical isolates. One hundred and forty-five strains were isolated from biopsy cultures obtained from adult patients. Antimicrobial susceptibility to amoxicillin, clarithromycin, metronidazole and tetracycline were tested using an agar dilution method. cagA and iceA genes and s1 and s2 alleles of vacA were studied by polymerase chain reaction. A group of patients had been previously treated for H. pylori infection. We found a resistance rate of 28.7% and 16.5% to metronidazole and clarithromycin, respectively. We did not find any resistance to amoxicillin or tetracycline. The cagA gene and s1 allele were detected in 86.3% and 65.2% of the strains. One hundred and two (71.3%) strains were iceA+. cagA+ strains showed lower percentages of resistance to antibiotics, as did vacA s1 and iceA+ strains. The role of lower rates of resistance to clarithromycin and metronidazole in more virulent H. pylori strains may have favorable effects in their eradication in patients infected with these strains.

[Bacteremia associated with mycotic aneurysm of the transversal aortic arch and myocarditis caused by Salmonella enteritidis]. / Bacteriemia asociada a aneurisma micótico de arco aórtico transverso y miocarditis por Salmonella enteritidis.

A 60-year-old male with diabetes mellitus had Salmonella enteritidis bacteremia associated with mycotic aneurysm of the transverse aortic arc and myocarditis. Antibiotic therapy with ampicillin and chloramphenicol was ineffective despite the fact that the microorganism was sensitive in vitro to those antimicrobials, and the patient had a progressive clinical deterioration which culminated in death.

Activity of cefotaxime and amikacin against 14,272 gram-negative bacteria from clinical samples in the period 1980 to 1985.

The sensitivity to cefotaxime and amikacin of 14,272 Gram-negative bacilli (Enterobacteriaceae and non-fermenting Gram-negative bacilli) isolated from clinical samples was studied during the period 1980 to 1985. The minimum inhibitory concentration (MIC) was determined by means of diffusion in agar. Strains were considered resistant to cefotaxime and amikacin if the MIC values were greater than 16 mg/L and greater than 8 mg/L, respectively. The MIC90 reached the critical value for cefotaxime in the case of Citrobacter spp., Escherichia coli, Klebsiella spp., Proteus mirabilis, Salmonella spp. and Shigella spp., and for amikacin in the case of Citrobacter spp., Enterobacter spp., E. coli, Klebsiella spp., P. mirabilis, Proteus vulgaris, Salmonella spp. and Serratia spp. Only Shigella spp. were sensitive to cefotaxime but not to amikacin, and only strains of Enterobacter spp. and Serratia spp. were sensitive to amikacin but not to cefotaxime.

Carbenicillin resistance of Pseudomonas aeruginosa.

Four strains of Pseudomonas aeruginosa obtained from clinical isolates which are carbenicillin resistant were studied to find the cause(s) of resistance to this beta-lactam antibiotic. The electrophoresis patterns of the four strains (PH20610, PH20815, PH4011, and PH4301) were found to be different from those of a wild-type strain, P. aeruginosa NCTC 10662, and appeared to lack penicillin-binding protein 2. Affinity of other penicillin-binding proteins from strains PH20610 and PH20815 for carbenicillin seemed to be normal or slightly diminished. Electrophoretic patterns of penicillin-binding proteins from strains PH4011 and PH4301 had more profound differences, since the affinities of their penicillin-binding proteins 1a, 1b, and 4 for carbenicillin were decreased by nearly two orders of magnitude relative to the preparations from the wild-type strain. Kinetic studies on binding of carbenicillin to penicillin-binding proteins both in isolated membrane preparations and in intact cells revealed that carbenicillin penetration into resistant cells was a much slower process than in susceptible cells, suggesting that the outer envelope structures serve as an efficient barrier against carbenicillin entry into our P. aeruginosa strains from clinical isolates.

[Comparative study of different serological tests for the diagnosis of brucellosis (author's transl)]. / Estudio comparativo de diversas pruebas en el diagnóstico serológico de la brucelosis.

The diagnosis of brucellosis is frequently a difficult one, and it is founded basically on the results of blood cultures and serological tests. Wright's classical agglutination test is commonly utilized in the serological diagnosis of brucellosis and its value is well established in the acute forms of the disease; for the diagnosis of subacute or chronic forms, however, a Coombs test must be performed to show incomplete antibodies. The agglutination carried out with serum treated with 2-mercaptoethanol allows the determination of the type of immunoglobulins present. Indirect immunofluorescence has been infrequently utilized in the diagnosis of brucellosis. The first three tests have been compared with indirect immunofluorescence using sera from 100 patients presenting with fever of unknown origin. All tests were negative in 40 sera, and of the 60 remaining sera only 32 were positive to all four tests. The highest titers were found with the Coombs test, while immunofluorescence yielded titers which were never above 1/320. Significant correlation coefficients were obtained between the tests. The best correlation was obtained between immunofluorescence and 2-mercaptoethanol, followed by immunofluorescence and Coombs, and by immunofluorescence and agglutination. Only immunofluorescence titers above 1/80 corresponded to the same of superior titers in the remaining tests; thus immunofluorescence titers below 1/80 can not be considered as diagnostic of the disease. The authors believe that immunofluorescence to 1/80 can be utilized as a quick routine test for the diagnosis of brucellosis, its disadvantages being a high cost and the requirement for an immunofluorescence microscope which may not be available in many laboratories.

[Bacteremia and sepsis due to Streptococcus agalactiae. Study of eight cases (author's transl)]. / Bacteriemia y sepsis por Streptococcus agalactiae. Presentación de ocho casos.

During a period of 29 months positive hemocultures to Streptococcus agalactiae corresponding to eight adult patients have been observed. These bacteria were apparently responsible for the clinical picture in five patients. In other two patients S. agalactiae appeared in the course of a sepsis caused by other germ. The remaining patient had a transient bacteremia and no treatment was required. Septic shock and bacterial endocarditis were the cause of death in two patients. Six patients cured. Literature on this subject is reviewed and the better prognosis of sepsis due to S. agalactiae in adults than in neonates is stressed. Endocarditis and meningitis occur as severe complications with poor prognosis. In patients with endocarditis the administration of penicillin and gentamicin as well as the consideration of early surgical replacement of the affected heart valve is recommended. Intravenous penicillin and gentamicin associated with intrathecal gentamicin are indicated in meningeal infections. Vancomycin is a good substitutive antibiotic in patients with penicillin hypersensibility.

Evolution of sensitivity to fosfomycin in bacteria isolated in 1973, 1974 and 1975 in the Servicio de Microbiologia y Epidemiologia of the 'Clinica Puerta de Hierro', Madrid.

The bacteriostatic activity of fosfomycin was studied in vitro against 1,243 clinical isolations of gram-positive cocci and 4,086 isolations of gram-negative bacilli that were obtained in 1973, 1974 and in the period from January to May of 1975. MIC was determined by the agar diffusion method, quantifying it by means of the standard curve that was worked out with the strain of E. coli NCTC 10,418. A slight increase in resistance was observed in the gram-positive cocci: 64 mug/ml were inhibitory for 63% of the 249 isolations obtained in 1973, 59.1% of the 716 isolations obtained in 1974, and 57.5% of the 278 isolations from 1975. A slight loss of sensitivity was also observed in the gram-negative bacilli: the aforementioned concentration of fosfomycin inhibited 36% of the 742 isolations from 1973, 33.6% of the 2,387 isolations from 1974 and 32.6% of the 957 isolations from 1975. 933 g of this antibiotic were consumed in our hospital in 1973, 4,203 g in 1974 and 957 g in 1975. The consumption rate per patient per year was 0.15, 0.72 and 0.20 g, respectively. In conclusion, although no change was observed in the sensitivity of some bacterial strains to fosfomycin, the overall study indicates a slight decrease in the sensitivity, although it does not apparently have any relationship to the consumption of fosfomycin in our hospital.

Interactions of fosfomycin with other antibiotics.

We selected 100 strains of organisms that were isolated in our hospital, which came from pathological products and which had an MIC of fosfomycin of 256 mug/ml or more and belonged to the genera Klebsiella, Pseudomonas, Escherichia coli, Serratia, Enterobacter, Proteus, Acinetobacter, Levinea and Staphylococcus. We have studied the effect of the association of fosfomycin with 15 antibiotics (beta-lactamins, cephalosporins, aminoglycosides, etc.) and 5 chemotherapeutics. The 11 selected strains were studied by the 'chess board' technique in agar. A study was also carried out on the action of fosfomycin on E. coli K12 E711 in the phase of logarithmic growth. The 11 selected strains were studied by the 'chess board' technique in agar. Synergic effect with fosfomycin associated to other antimicrobials was found in 9 strains.