Epidemiological markers of Acinetobacter baumannii clinical isolates from a spinal cord injury unit

During a period of 28 months, 114 isolates of Acinetobacter baumannii obtained from urine samples of 57 patients, were recovered in a Spinal Cord Unit; an unusual increase in the number of A. baumannii isolates was observed between February 1991 and January 1992. Six different typing methods [biotyping, antimicrobial susceptibility, whole cell and cell-envelope protein analysis, plasmid analysis and chromosomal DNA analysis by pulsed-field gel electrophoresis (PFGE)] were used to study the isolates to establish any potential relationships among them. Chromosomal DNA analysis by digestion with ApaI and separation of the fragments by PFGE was the most powerful tool to determine the relatedness of isolates. The results suggest that the isolates from 1991 and 1992 may have originated from strains present in 1990 that subsequently acquired resistance to amikacin and tobramycin during the epidemic.

Fluconazole, itraconazole and ketoconazole in vitro activity against Candida spp

The in vitro activity of fluconazole, itraconazole and ketoconazole against 625 Candida yeast strains from patients treated at the University Hospital of the Canaries, by means of a micromethod of dilution in broth enriched with Yeast Nitrogen Base (YNB), and buffered to pH7, has been assessed. Species distribution was as follows: Candida albicans (388), Candida tropicalis (84), Candida glabrata (84), Candida parapsilosis (69). Our results show 10.0% and 8.8% of C. albicans resistant to itraconazole and fluconazole, respectively, and 1.8% resistant to ketoconazole; 39.5% of C. tropicalis were resistant to itraconazole, 34.5% to fluconazole and 2.4% to ketaconazole. 19.1% of C. glabrata were resistant to fluconazole and 13.1% to itraconazole; 4.4% of C. parapsilosis were resistant to fluconazole and 1.5% to itraconazole. In general C. tropicalis was the most resistant strain and C. parapsilosis the most sensitive. The greatest percentages of resistance in vitro were seen with the two triazols.

[Gardnerella vaginalis as urinary pathogen]

AIM

To study the significance of Gardnerella vaginalis in urine by comparing urine culture results, leucocytes count and clinical findings.

METHODS

A total of 1,365 urine specimens submitted consecutively were inoculated on Bilayer media. G. vaginalis was recovered from 76 urine specimens with the following distribution: in 12 samples G. vaginalis was isolated as the only organism, 9 with counts > 10(5) CFU/ml and 3 between 10(5)-10(3); in the remaining 64 samples G. vaginalis was always found in counts > 10(5) CFU/ml but associated in 13 occasions with another organism and in 51 occasions with 2 or more organisms from the periurethral and vaginal flora.

RESULTS

G. vaginalis in pure cultures corresponded to 8 women and 4 males whose ages ranged from 20 to 86 years. Six patients complained of symptoms of lower urinary tract infection (UTI), 3 had fever and in 3 the urine culture was practised as a control. Seven patients presented predisposing factors to UTI and 2 were pregnant. In only 2 cases pyuria was detected. Of 12 patients with pure cultures, only 3 were found to have G. vaginalis UTI.

CONCLUSIONS

Our data indicate that G. vaginalis in urine not always implies an UTI and that this organism is found most often in patients with predisposing factors.

In vitro susceptibility of 545 isolates of Candida spp. to four antifungal agents

The in vitro susceptibility to amphotericin B, fluconazole, itraconazole and ketoconazole of 545 Candida strains from patients treated at the University Hospital of the Canaries was determined by means of a microdilution test. The distribution of the species was as follows: Candida albicans (342), Candida tropicalis (70), Candida glabrata (68), Candida parapsilosis (65). Of Candida albicans isolates, 8.5% and 7.6% showed resistance to itraconazole and fluconazole respectively. Of C. tropicalis isolates 34.3%, 27.1% and 2.9% were resistant to itraconazole, fluconazole and ketaconazole respectively. For C. glabrata, 10.3% and 4.4% of the isolates under study demonstrated resistance to fluconazole and itraconazole respectively. Only 4.6% and 1.5% of C. parapsilosis isolates demonstrated resistance to fluconazole and itraconazole respectively. C. tropicalis was the most resistant strain and C. parapsilosis the most sensitive. The greatest percentages of resistance in vitro were seen with the triazoles.

[The effect of sepsis on liver protein synthesis]

A study was made of the possible influence of sepsis on liver protein synthesis in septic and control rats, fed either parenterally (TPN) or with water and feed available "ad libitum". Liver protein synthesis was determined using the single massive dose method. In experiment I, the septic and control animals received TPN for twenty-four hours: in experiment II water and food was available to them "ad libitum". Twenty-four hours after the sepsis occurred, the animals were injected with a massive dose of 14C-labelled leucine, and slaughtered by decapitation. The septic animals with water and feed available "ad libitum" were fasted voluntarily without any intake. This group of fasted septic animals was the only one which lost weight. Liver protein synthesis increased in septic animals in comparison with the control animals, whether receiving TPN (112.2 +/- 8/78.5 +/- 13) or with "ad libitum" nutrition (97.2 +/- 15/60.8 +/- 8). The increased liver protein synthesis in the septic animals was modified (although with reduced significance) by parenteral nutrition (112.2 +/- 8/97.2 +/- 15). Our results suggest that sepsis increases liver protein synthesis, and that this protein synthesis may be enhanced by parenteral nutrition.

[A urinary outbreak of Acinetobacter baumanii in a spinal cord injury unit]

From January 1990 to April 1992, 114 urinary strains of Acinetobacter baumanii were isolated in 57 patients with traumatic spinal cord [correction of medular] injury. The strains were characterized by having all of them the same biochemical identification, except for citrate, maltose and tryptophan-desaminase. Until December 1990, (5 strains) were resistant to all antibiotics, except to tobramicine, amikacine, cotrimoxazol and imipenem (6.3%, 33.9%, 26.7% and 0% of resistances, respectively); since January 1991, (99 strains) became resistant to all of them, except to imipenem. 39.5% of AB were isolated in pure cultures, 46% of them with pyuria. Between February 1991 and January 1992, we observed the highest number of affected patients, although without seasonal predominance. We observed as well a higher incidence among males (46 males, 11 females). 80% of them carried a permanent probe. Only 6 patients presented clinical signs directly related to AB. The environmental study could not demonstrate any source of contagion or transmission mechanism.

[The isolation and identification of Mobiluncus curtisii and Mobiluncus mulieris in genital specimens]

Amongst 1.202 genital samples studied, the microscopic exam revealed in 179 (14.8%) cases flora compatible with bacterial vaginitis. Of these 179 samples, Mobiluncus SP was observed in 35 (19.6%) using Gram staining and in 18 (10.1%) this microorganism was isolated in agar RLK and anaerobic atmosphere. Using biochemical characterization M. curtisii species was found more frequently (15 isolations) than M. mulieris (3 isolations). Chromatographic characterization permitted the diagnosis of the genus but not the differentiation of the species. Out of the 35 cases of Mobiluncus observed microscopically, 11 (31.4%) were afterwards isolated while in 7 occasions Mobiluncus growth was obtained without having been previously visualized using Gram staining. The percentage of Mobiluncus observed was different according to the species since 2 of the 3 M. mulieris while only 9 out of the 15 M. mulieris were visualized.

[Evaluation of a new method for urine screening based on the study of catalase]

A new method of urine screening based on the enzymatic study of catalase (Uriscreen) was evaluated. Catalase is produced by the majority of microorganisms that cause urinary infections as well as by red cells, uroepithelial cells and PMN. In 553 consecutive urine samples we studied the sediment, the conventional culture, and the Uriscreen test. Comparative study between culture and Uriscreen revealed a sensitivity of 92.3%, specificity of 83.3%, negative predictive value of 96.2%, and positive predictive value of 69.9%. In 86% of the samples the results obtained with both techniques were similar, whereas in 14% of the cases they failed to coincide. Among the 74 cases of disagreement, 12 were false negative (culture positive, Uriscreen negative) and 62 were false positive (culture negative, Uriscreen positive). The high sensitivity and negative predictive values obtained with the screening method indicate that this is an useful procedure for the study of negative urines since it allows to rapidly classify 60.2% of the samples.

[Type 1 fimbriae, P fimbriae and X adhesins in Escherichia strains causing pyelonephritis, cystitis and recurrent urinary infections]

The presence of type 1 fimbriae, P fimbriae and X adhesins in 30 strains of Escherichia coli producing pyelonephritis, 30 strains producing cystitis, and 30 strains producing recurrent urinary infections are compared. All the strains were collected from adult women without risk factors for infections of the urinary tract. The presence of P fimbriae was 73% in strains producing pyelonephritis, 40% in strains producing cystitis and 20% in strains producing recurrent urinary infections; the presence of X adhesins was 3%, 0, and 17% respectively. There were, in consequence, significant differences between the groups studied; however, such differences were not observed with respect to the presence of type 1 fimbriae, which was 97%, 97% and 90%, respectively. We conclude that P fimbriae act as a factor of greater virulence in the strains of E. coli producing pyelonephritis and X adhesins are found almost exclusively in the strains producing recurrent urinary infections.

[Haemophilus influenzae and Haemophilus parainfluenzae: etiologic agents of sexually transmitted diseases?]

In 573 urethral swabs, 3 Haemophilus influenzae (HI) and 7 Haemophilus parainfluenzae (HPI) were isolated; 7 of the patients had clinical features of urethritis and in 3 another genital pathogen was associated. Biotype IV was the predominant one in HI, and II in HPI. In 6.259 endocervical and/or vaginal swabs 15 HI and 5 HPI were isolated. Three out of the 15 females infected by HI, had clinical features of salpingitis and 8 of vaginitis; 5 of them were carriers of an IUD. In four out of the 5 females with HPI another genital pathogen coexisted, and in the fifth there was an additional non analysable isolate. Biotype I predominated in HI and biotype II in HPI.

[Type 1 fimbriae and P fimbriae in E. coli producing chronic prostatitis]

The fimbriated adhesines constitute a factor of virulence of E. coli in the urinary tract infections. The presence of type 1 fimbriae and fimbriae P was evaluated in 23 E. coli strains isolated with patients with chronic bacterial prostatitis. For the diagnosis of prostatitis the Stamey test was used. The detection of the type 1 fimbriae was carried out by agglutination of the E. coli strains with Saccharomyces cerevisiae and that of fimbriae P with PPA test. 95.7% of the evaluated strains had type 1 fimbriae and 52.2% had fimbriae P. It is concluded that type 1 fimbriae are common in all strains associated with urinary tract infection, without any relationship between their presence and the localization of infection, and that the presence of fimbriae P is not a constant feature of the E. coli strains associated with chronic prostatitis.