Impact of nosocomial polymicrobial bloodstream infections on the outcome in critically ill patients.

The aims of this study were to compare the clinical and microbiological characteristics from patients with polymicrobial bloodstream infections (BSI) to those from patients with monomicrobial BSI and to determine their influence on the prognosis. A prospective study was conducted on 371 nosocomial BSI in an intensive care unit (ICU). Seventy-five (20.2%) of them were polymicrobial. The mean APACHE II score at the onset of bacteremia in polymicrobial and monomicrobial BSI were 17.7 ± 6.6 and 18.9 ± 7.5, respectively (p=0.228). Severe sepsis and septic shock were present in 68.0% and 50.6% of polymicrobial BSI and in 73.9% and 55.1% of monomicrobial BSI, respectively (p=0.298 and p=0.494, respectively). The length of stay and the length of stay post-infection were significantly longer in patients with polymicrobial BSI. APACHE II score at the onset of BSI, high-risk microorganisms, and septic shock were predictors of related mortality, but polymicrobial BSI and inadequate empirical antimicrobial treatment were not. Our findings suggest that the clinical and microbiological characteristics of polymicrobial BSI are not different from monomicrobial BSI, and polymicrobial BSI do not have any influence on the related mortality. However, they occurred in patients with a longer length of stay in the hospital and were associated with longer stays in the hospital after the episode of BSI.

Clinical significance of the detection of Candida albicans germ tube-specific antibodies in critically ill patients.

The present study, comprising a prospective multicentre study including 53 non-neutropenic patients from intensive care units (ICU) in six Spanish tertiary-care hospitals, was carried out to determine the clinical significance and influence on mortality of Candida albicans germ tube-specific antibodies (CAGTA). There were 22 patients (41.5%) for whom the CAGTA results were positive, although none of had a blood culture positive for Candida. The intra-ICU mortality rate was significantly lower (p = 0.004) in CAGTA-positive patients (61.2% vs. 22.7%). Multivariate analysis confirmed that a positive CAGTA result was the only protective factor to be independently associated with ICU mortality (beta coefficient = -0.3856; 95% confidence interval = -0.648 to -0.123).

The influence of inadequate empirical antimicrobial treatment on patients with bloodstream infections in an intensive care unit.

OBJECTIVE: To determine the occurrence of inadequate antimicrobial therapy among critically ill patients with bacteremia and the factors associated with it, to identify the microorganisms that received inadequate antimicrobial treatment, and to determine the relationship between inadequate treatment and patients outcome. METHODS: From June 1995 to January 1999 we collected data on all clinically significant ICU-bacteremias in our teaching hospital. Clinical and microbiological characteristics were recorded and the adequacy of empirical antimicrobial treatment in each case was determined. We defined inappropriate empirical antimicrobial treatment as applying to infection that was not being effectively treated at the time the causative microorganism and its antibiotic susceptibility were known. Multivariate analysis was used to determine the variables associated with inappropriate empirical antimicrobial treatment and to evaluate the influence of this on the related mortality to bacteremia, using the SPSS package (9.0). RESULTS: Among 166 intensive care unit patients with bacteremia, 39 (23.5%) received inadequate antimicrobial treatment. In this last group the mean age of patients was 64.1 +/- 13.2 years, and 64% were men. Bacteremia was hospital-acquired in 92% of these cases. Eleven percent developed septic shock and 37.7% severe sepsis, and ultimately fatal underlying disease was present in 28.2% of patients given inadequate empirical antimicrobial treatment. The main sources of bacteremias in this group were: a vascular catheter (15.3%), respiratory (7.6%) or unknown (53.8%). The microorganisms most frequently isolated in the group with inadequate empirical antimicrobial treatment were: coagulase-negative staphylococci (29.5%), Acinetobacter baumannii (27.3%), Enterococcus faecalis, Pseudomonas aeruginosa, Enterobacter cloacae, Proteus mirabilis, Escherichia coli, and Candida species (4.5% each). The frequency of coagulase-negative staphylococci in the cases with inappropriate treatment was higher than in the group with appropriate treatment (OR 2.62; 95% CI: 1.10-6.21; P = 0.015). The global mortality rate was 56% and the related mortality was 30% in the group with inadequate empirical antimicrobial treatment. The only factor associated with inappropriate empirical antibiotic treatment was the absence of abdominal or respiratory focus (P = 0.04; OR = 0.35; 95% CI: 0.12-0.97). Septic shock was related to attributable mortality (P = 0.03; OR = 3.19; 95% CI: 1.08-9.40), but not inappropriate empirical antibiotic treatment (P = 0.24; OR = 1.71; 95% CI: 0.66-4.78). CONCLUSION: Almost a quarter of critically ill patients with bloodstream infections were given inadequate empirical antibiotic treatment, but mortality was not higher in the group with inadequate treatment than in the group with adequate treatment. This fact was probably due to microbiological factors and clinical features, such as the type of microorganism most frequently isolated and the source of the bacteremia.

Comparison of PCR mediated amplification of DNA and the classical methods for detection of Mycobacterium leprae in different types of clinical samples in leprosy patients and contacts.

Traditional staining and microscopic examination techniques for the detection of Mycobacterium leprae, DNA amplification by polymerase chain reaction (PCR) of a 531-bp fragment of the M. leprae specific gene encoding the 36-kDa antigen, and serodiagnosis with M. leprae specific antigens (PGL-1 and D-BSA) were compared on different clinical specimens (serum samples, slit-skin smears, biopsies and swabs) from 60 leprosy patients attending the Sanatorium of Fontilles. Patients were divided into groups; (i) 20 multibacillary patients (MB) with positive bacteriological index (BI) by conventional methods and on WHO multidrug therapy (MDT); (ii) 30 MB patients with negative BI and completed minimum 2 years treatment MDT; (iii) 10 paucibacillary (PB) patients who had completed 6 months MDT at least 8 years ago. Control groups included four non-leprosy patients for PCR methods and 40 health control patients and 10 tuberculosis patients for serological methods. In the multibacillary BI positive group, there was a good correlation between all methods. All tests were negative in the paucibacillary group, although only a few patients were tested and all had been treated many years ago. One must be cautious concerning the diagnostic potential of these techniques in this type of leprosy. We also studied different combinations of leprosy diagnosis methods to determine the potential risk in a leprosy contact individuals group. The prevalence of antibodies to M. leprae antigens in serum was measured, together with the presence of M. leprae DNA in the nose and lepromin status in a group of 43 contacts of leprosy patients (12 household and 31 occupational) to evaluate the maintenance of infection reservoirs and transmission of the disease. Only two individuals were found to form a potential high risk group.

Serological response (Western blot) to fractions of Mycobacterium tuberculosis sonicate antigen in tuberculosis patients and contacts.

OBJECTIVE: To assess the serological response to fractions of Mycobacterium tuberculosis sonicate antigen by Western blot analysis in patients with tuberculosis and contacts. METHODS: We studied 71 individuals including 43 patients with active tuberculosis, 16 contacts and 12 healthy blood donors. For Western blot analysis, M. tuberculosis (H37Rv strain) sonicate antigen extract was fractionated by electrophoresis on polyacrylamide gel (SDS-PAGE). RESULTS: We obtained antibody responses directed against four antigenic fractions with molecular weights of 71, 65, 26-38 and 19 kDa. Sixty per cent of pleural tuberculosis and 52.4% of smear-positive pulmonary tuberculosis had whole responses against all four fractions; there were no partial responses in these groups. For patients with smear-negative pulmonary tuberculosis whole responses were 17.6% and partial responses 41.2%. All contacts whose tuberculin tests converted from negative to positive (three cases) reacted exclusively against the 19 kDa fraction. CONCLUSIONS: Western blot-positive results in patients with pleural and smear-positive pulmonary tuberculosis were characterised by a whole pattern against all four antigenic fractions, whereas patients with smear-negative pulmonary tuberculosis showed heterogeneous results. The exclusive response against the 19 kDa fraction observed in contacts with tuberculin conversion could help to identify candidates for preventive therapy.

Pneumococcal pyomyositis.

Pyomyositis is most commonly caused by Staphylococcus aureus. A 25-month-old child developed infection of the biceps brachialis muscle caused by Streptococcus pneumoniae. The child had no underlying immune or anatomic defect.

Application of an optimized and highly discriminatory method based on arbitrarily primed PCR for epidemiologic analysis of methicillin-resistant Staphylococcus aureus nosocomial infections.

The optimization of an arbitrarily primed PCR method for typing 96 methicillin-resistant Staphylococcus aureus (MRSA) isolates was compared with pulsed-field gel electrophoresis. Identical results in the differentiation of MRSA clones and identification of the main cluster that included 82 strains (88% of patients) were obtained by both techniques.

[Tuberculosis in AIDS patients: the contribution of an analysis of the restriction fragment length polymorphism of Mycobacterium tuberculosis isolates]. / Tuberculosis en pacientes con SIDA: aportación del análisis de los fragmentos de restricción de longitud polimórfica aislados de Mycobacterium tuberculosis.

BACKGROUND: In this report we study tuberculosis transmission in HIV infected patients using molecular epidemiological methods. PATIENTS AND METHODS: We have studied 60 M. tuberculosis isolates from 30 HIV infected cases, and their clinical-epidemiological data. Susceptibility to tuberculostatic agents and electrophoretic patterns using RFLPs (restriction fragment length polymorphisms) method were evaluated. Dice's coefficient was used for the similarity analysis. RESULTS: Over 73% studied patients were included in clusters using RFLPs analysis. This data show that nearly 60% of the tuberculosis cases in our area have a recent transmission. Forty per cent of these cases were included in the main cluster. The frequency of tuberculostatic-resistant strains in HIV infected patients was similar to the that of observed in other patients. We did not find correlation between RFLPs clusters and clinical-epidemiological data. CONCLUSIONS: Tuberculosis transmission in HIV-positive patients using RFLPs as molecular marker shows that 60% of the cases are caused by recently acquired strains. We did not find multi-drug resistant strains in our isolates. However due to the high transmissibility of these circulating clones, control disease measures in this group of risk population are required.

DNA amplification fingerprinting for subtyping Neisseria gonorrhoeae strains.

BACKGROUND AND OBJECTIVES: DNA amplification fingerprinting is used in most epidemiologic studies as a substitute for conventional typing methods. DNA amplification fingerprinting and conventional typing methods were compared in this epidemiologic study of Neisseria gonorrhoeae. GOAL OF THIS STUDY: To differentiate 70 Neisseria gonorrhoeae isolates from untreated patients with urogenital gonococcal infection. STUDY DESIGN: Gonococcal strains were characterized by auxotyping, serotyping, plasmid profile, antibiotic sensitivity, and DNA amplification fingerprinting. The method of unweighted pair-group average linkage was used for cluster analysis. Discriminatory power was calculated applying Simpson's index. RESULTS: Amplification of Neisseria gonorrhoeae DNA with primers OPA-03 and OPA-13 produced well-resolved patterns of 15 and 22 DNA fragments, respectively, with a discriminatory power (0.978 with OPA-13 and 0.967 with OPA-03) comparable to that obtained with auxotyping/serotyping combination (D:0.968) or with auxotype/serotype/plasmid profile combination (D:0.983). Correlation between DNA amplification fingerprinting pattern and auxotype/serotype class was not always uniform. Some strains with the same auxotype/serotype/plasmid profile were subdivided by DNA amplification fingerprinting, and vice versa. CONCLUSION: Although auxotype/serotype class and DNA amplification fingerprinting can be used in the epidemiologic characterization of strains, DNA amplification fingerprinting offers a better discriminatory index than the separate serotyping. It is especially useful for differentiating serologically identical strains and nontypable strains. A combination of serotyping and DNA amplification fingerprinting seems to be the best way to differentiate Neisseria gonorrhoeae strains in epidemiologic studies, bringing together the most simple techniques and the best discriminatory power among isolates.

Use of genomic fingerprinting in the characterization of Neisseria gonorrhoeae isolated in Valencia, Spain.

Ninety-five Neisseria gonorrhoeae organisms isolated in Valencia, Spain, were characterized by antibiotic sensitivity testing, auxotyping, serotyping, plasmid analysis and restriction endonuclease fingerprinting (HindIII digestion). Cluster analysis of the restriction patterns revealed that 31 isolates (32.6%) formed 12 clearly defined clusters. Penicillinase-producing Neisseria gonorrhoeae strains formed four of these groups. Eight groups of gonococcal strains were identified by auxotyping, although 83% of isolates belonged to two auxotypes (Proto, Pro-). Twenty-three different serovars were identified by serotyping. The serovar pattern IB/rop was found in 38% of isolates. A 60% coincidence was found between gonococcal groupings obtained by combination of auxotyping, serotyping and plasmid analysis and those obtained with the restriction enzyme fingerprinting technique. The specificity of enzyme restriction patterns of Neisseria gonorrhoeae is confirmed to be of practical importance in the epidemiologic study of gonorrhoea.

Genomic fingerprinting of penicillinase-producing strains of Neisseria gonorrhoeae in Valencia, Spain.

OBJECTIVE: To compare the value of different markers and their combinations with the restriction enzyme technique in the differentiations of penicillinase-producing N. gonorrhoeae (PPNG) strains. MATERIALS AND METHODS: 17 PPNG strains isolated from symptomatic, untreated male patients with urethritis were characterised by antibiotic sensitivity testing, auxotyping, serotyping, plasmid profile, and restriction endonuclease fingerprinting (Hind III digestion). Cluster analysis with the method of unweighted pair-group average (UPGMA) linkage was used to calculate similarity or dissimilarity for PPNG strains. MAIN RESULTS: Either auxotyping or plasmid profile alone differentiated three groups of PPNG strains, whereas the combination auxotyping/serotyping identified 10. Although the combination auxotyping/serotyping/plasmid profile and the restriction enzyme technique showed a similar discrimination ability (differentiation of 11 PPNG strains), genomic fingerprinting gave highly specific restriction patterns on individual gonococcal isolates. CONCLUSIONS: The combination of different markers gave more epidemiological information than the use of only one. The sequence of discriminating ability for PPNG strains was: auxotyping/serotyping less than auxotyping/serotyping/plasmid profile less than restriction patterns of genomic DNA.

[Membrane proteins electrophoretic profiles study applied to Neisseria gonorrhoeae epidemiology]. / Aplicación del estudio de los perfiles electroforéticos de proteínas de membrana en la epidemiología de Neisseria gonorrhoeae.

The analysis of electrophoretic profiles of membrane proteins is one of the epidemiological methods of bacterial typing. The profiles of membrane proteins of 95 isolates were studied for valuing their usefulness in the epidemiology of N. gonorrhoeae. The results were compared with the obtained using other characterization methods (auxotyping, serotyping and antimicrobial sensibility). The proteins I and II (PI and PII) showed clear differences between isolates. Only protein-I (PI) with constant molecular weight for each isolate was valid to discriminate between strains. It was observed correlation between serovariety IA and molecular weight of PI 33.6-36 kD, and the serovariety IB with molecular weight 35.5-37 kD. Though it wasn't possible discriminated between the different serovarieties. It was proved a sensibility decrease to penicillin, tetracycline and cloramfenicol in those strains with molecular weight of PI greater than 35.5 kD (serogroup WII/WIII). In the 80% of the isolates considered multiple antibiotic-resistant it was observed a significant increase of the membrane protein dough of 52 kD. All the strains with this protein increased were multiple antibiotic-resistant.

[Acute fatty liver in pregnancy. Presentation of a case]. / Hígado graso agudo del embarazo. Presentación de un caso.

Acute fatty liver of pregnancy (AFLP) is not a very frequent disease, of unknown etiology mainly present in the 3rd trimester of the pregnancy. Early diagnosis and treatment including interruption of pregnancy (delivery or caesarean section) had been the key for decreasing fetal-maternal morbidity-mortality in recent years. This paper analyzes a clinical report of a 30 years old woman suffering AFLP histologically confirmed admitted to our hospital two weeks after illness started and who died because of secondary complications which did not respond to management probably because it was too late.