Mycobacterial testing in hospital laboratories: results from a questionnaire survey in Italy.

Between 1999 and 2001, 355 hospital laboratories in Italy were asked to complete a questionnaire addressing mycobacterial test methods, 1-year workloads and laboratory safety features. Analysis of the data showed that rapid methods for mycobacterial testing were being used by most larger laboratories; however, sub-optimal methods were still in use in small and medium-size laboratories. In a country such as Italy, which has a low prevalence of tuberculosis cases, implementation of rapid technologies, combined with regionalisation of mycobacterial diagnostic services, seems to be the most reasonable and cost-effective strategy.

Diagnostic paracentesis. A two-step approach.

Diagnostic paracentesis is usually considered the first test to be performed in the assessment of the ascitic patient and a large number of investigations on ascitic fluid have been proposed. To assess the value of a simplified procedure, serum to ascites albumin gradient and ascitic white blood cell counts were employed as a first step. One hundred and fifty-three paired serum and ascitic fluid samples were analysed and allowed patients to be divided into three groups: 1) serum to ascites albumin gradient > = 11 g/L and white blood cells < 0.5 x 10(9)/L predicted cirrhosis (or liver carcinoma) without peritonitis with 83% efficacy, 96% positive predictive value and 65% negative predictive value; 2) serum to ascites albumin gradient > = 11 g/L and white blood cells > = 0.5 x 10(9)/L predicted cirrhosis (or liver carcinoma) with peritonitis with 86% efficacy, 45% positive predictive value and 99% negative predictive value; 3) serum to ascites albumin gradient < 11 g/L predicted the other diagnoses with 92% efficacy, 77% positive predictive value and 95% negative predictive value. As serum to ascites albumin gradient > = 11 g/L and white blood cells < 0.5 x 10(9)/L predicted cirrhosis (or liver carcinoma) without peritonitis in 96% of the cases and excluded peritonitis in 99% of the cases, further fluid ascitic analyses could be considered as a second step only in patients with serum to ascites albumin gradient < 11 g/L and/or white blood cells > = 0.5 x 10(9)/L. In a group of ascitic patients where the prevailing diagnosis is cirrhosis (or liver carcinoma) without peritonitis, this simplified approach could provide a favourable cost/benefit ratio.

[Hemolytic properties of Escherichia coli strains isolated from cases of urinary tract infection and enteropathy]. / Proprietà emolitiche di stipiti di Escherichia coli isolati in casi di infezione delle vie urinarie e di enteropatia.

Different strains of E. coli, that were isolated during years 1986-1990 from 217 urine samples in patients with asymptomatic bacteriuria, cystitis, cysto-pyelitis and pyelonephritis, appeared to be more frequently haemolytic (34.5%) than strains of E. coli isolated from faecal samples in patients with acute enteropathy. It was confirmed that the haemolysin production occurs during log -phase of bacterial growth. The degree of haemolysis can vary widely according to the strain involved. Agglutination tests, using 53 O-antiserum, showed a great variety of serogroups. Some of them (04, 018, 022) are prevalent among the haemolytic strains isolated from urine; some others (055, 0111, 075) are prevalent among the anhaemolytic strains isolated from urine and faeces.

[Various biotypes of Escherichia coli: their correlation with antibiotic resistance]. / Biotipi diversi di Escherichia coli: loro correlazione con l'antibiotico resistenza.

The antimicrobial susceptibilities of 572 strains of Escherichia coli were evaluated. The strains were divided according to the biotypes and the differences between the strains towards various antibiotics were examined. We found a correlation between biotype and antibiotype. This correlation lead us to think of a possible existence of more resistant biotypes than others. Now we are doing other studies in order to show if this correlation is constant during time and if similar differences are present for other microorganisms, as well.

[Identification of Enterobacteriaceae using the ABAC-ABACTOR II semiautomatic system]. / Identificazione di "Enterobacteriaceae" mediante il sistema semiautomatico ABAC-ABACTOR II.

The validity of the semi-automatic ABAC-ABACTOR II system in diagnostic use has been confirmed with identification and control assays of 238 strains of Enterobacteriaceae.

In vitro antibacterial activity of ceftizoxime.

During 1983, the antibacterial activity of ceftizoxime has been tested in vitro against 325 strains of Enterobacteriaceae, Streptococcaceae, Micrococcaceae, Pseudomonaceae and Acinetobacter sp. isolated from material of human origin (blood, urine, faeces, sputum, various exudates). Except for S. faecalis and some strains of P. rettgeri, P. aeruginosa, A. calcoaceticus, Staphylococcus spp. all the strains examined were found to be sensitive to the antibiotic, whose MIC was 0.05-1.5 micrograms/ml in the great majority of cases. For 72 ceftizoxime-sensitive strains the MBC/MIC ratio was nearly always under 4:1, confirming the drug's bactericidal activity. On strains of Enterobacteriaceae (E. coli, K. pneumoniae, S. marcescens, S. typhimurium) MIC of ceftizoxime achieved a minimum bactericidal time (MBT) between 3 and 4 hours of bacteria-antibiotic contact, and bacterial survival percentages were, in any case, very low as early as the 1st hour.

[Transferable antibiotic resistance of Salmonellae isolated at the Novara General Hospital in 1977]. / Antibiotico-resistenza-trasferibile in salmonelle isolate presso l'Ospedale Maggiore di Novara nel 1977.

Of 74 strains of Salmonella isolated by the Laboratory of Microbiology of the Hospital of Novara in 1977 and belonging to 20 different serotypes, transfer of antibiotic-resistance, mostly multiple (Streptomycin, Chloramphenicol, Kanamycin, Tetracycline, Ampicillin) has been detected in 78,5% of 28 antibiotic-resistant strains. As in previous investigations made by the same Laboratory, the highest percentages of transfer of resistance have been observed in some serotypes (S. typhi murium, S. panama), while that was observed only in S. enteritidis isolated in 1977. At last in this period was S. wien able to transmit multiple resistance isolated only once.