Fluoroquinolone resistance in hematopoietic stem cell transplant recipients with infectious complications.

The infectious complications are an important cause of morbidity and mortality in hematopoietic stem cell transplant (HSCT) recipients. Our retrospective study has the objective to evaluate the incidence, clinical and bacteriologic features of documented infections in these patients. The frequency of infectious complications was analysed in 42 patients with hematologic malignancies who received HSCT from January to December 2002 at Pisa General Hospital. Thirty-three patients underwent autologous HSCT and 9 received allogeneic HSCT. All patients received acyclovir, fluconazole and fluoroquinolones as prophylactic regimen. A total of 38 infectious episodes were recognized in 22 patients during the early post-HSCT period (N=27) and in the late post-HSCT period (N=11). Infectious complications rate correlated positively with the deepness and length of neutropenia in the early period. There were 21 episodes of sepsis (the majority by coagulase negative staphylococci), 2 pneumonias and 1 vertebral osteomyelitis. All staphylococcus strains were, in vitro, resistant to oxacillin and ciprofloxacin and 8 out of 15 gram negative rods were resistant to ciprofloxacin. Most of the infectious complications were cured with appropriated antimicrobial therapy and/or with engraftment and, in 4 cases, with central catheter removal. One patient developed a positive CMV antigenemia; a pre-core mutant form of HBV reactivation was diagnosed in another patient. No cases of invasive fungal infections were recognised. Five patients died but only one from infection (septic shock). Pneumonia was a coexisting cause of death in 2 patient in the late period. We can conclude that most of infectious complications, that occurred in the early period post-HSCT were due to coagulase negative staphylococci and gram negative rods resistant to ciprofloxacin. For this reason, the usefulness of fluoroquinolone prophylaxis in HSCT recipients should be reevaluated.

Surgical management of knee dislocations with ligament reconstruction associated with a hinged external fixator.

INTRODUCTION: Knee dislocations are defined as ligament injuries involving at least two of the four most important knee ligaments. Results from recent studies have shown a tendency towards improvement of the functional outcomes with use of an articulated external fixator during the postoperative period following multiligament reconstruction. Our hypothesis was that good knee stability and early gain of range of motion could be achieved with the use of the external fixator after ligament reconstructions. METHODS: Fourteen patients with knee dislocations were evaluated after multiligament reconstruction in association with use of a lateral monoplanar external fixator for six weeks. Reconstructions were performed using grafts from a tissue bank. Range of motion was measured after one, two, three, six, twelve months and at the final evaluation at a mean time of 49 months. The assessments were made using objective and subjective IKDC, Lysholm and Tegner scales. RESULTS: The mean scores were 71.7 for the subjective IKDC score, 81.5 for the Lysholm score. No patient was able to return to previous Tegner score. Out of the 45 ligament reconstructions performed, only four failed during the follow-up time. The mean range of motion of the knee presented a progressive increase from the first to the twelfth month, from 67.8° to 115.7°. Two cases of superficial infection on the site of the external fixator pins were observed. CONCLUSION: The use of an external fixator enabled early rehabilitation with range of motion gains starting from the first postoperative month, a low rate of reconstruction failure and minimal complications. Nevertheless, none of the patients returned to the level of activity prevailing prior to the injury. LEVEL OF EVIDENCE: Level IV, retrospective therapeutic case series.

Comparative study of the in vitro antibacterial activity of ciprofloxacin and thirteen other antimicrobial drugs with respect to recently isolated pathogens.

The in vitro antibacterial activity of ciprofloxacin and 13 other antimicrobial drugs was evaluated with respect to 569 pathogens, mainly isolated from urine. Ciprofloxacin was found active in 96.1% of all of the Gram-positive and Gram-negative strains tested, amikacin in 90.6%, ceftazidime in 89.8%, ceftriaxone in 85.3%, piperacillin in 82.7%, tobramycin in 82.6%, gentamicin in 81.5%, aztreonam in 78.3%, nitrofurantoin in 72.6%, cotrimoxazole in 71.6%, cinoxacin in 71.0%, pipemidic acid in 70.6%, nalidixic acid in 66.7%, ampicillin in 50.1%. Ciprofloxacin was found to be the most active of the drugs studied against the bacterial strains which cause urinary, respiratory and other infections.

Bloodstream infections in HIV-positive patients: a review of sixty-eight episodes.

A retrospective review of all episodes of bloodstream infection (BSI) in HIV-positive patients admitted to the Infectious Diseases Unit at the Pisa General Hospital from 1991 to 1994 was performed. Sixty-eight episodes of BSI were recorded in 61 patients (5.8% of all patients admitted for HIV infection). BSI was community-acquired in 64.7% of cases. The patients were mainly male and i.v. drug abusers with a mean age of 33.8 yrs +/- 5.6 S.D. Sixty-four episodes occurred in AIDS patients (CDC criteria). CD4 count was less than 100 in 49 patients. The most frequent isolates were coagulase-negative staphylococci 33, S. aureus 7, Pseudomonas spp 7, fungi 1, non-typhoidal Salmonella 4. The most common sources of BSI were the skin or subcutaneous tissue infections and intravascular catheters. The overall mortality associated with BSI was 27.3%. Vancomycin and teicoplanin were active in vitro against all but one of the staphylococcal isolates.

Activity of vancomycin against recently isolated nosocomial gram-positive cocci.

This study reports the in vitro activity of vancomycin against 174 Gram-positive cocci isolated in nosocomial patients. Vancomycin was shown to have a slightly better activity than teicoplanin and was the most active of all other agents tested including imipenem, new quinolones and aminoglycosides.

Penetration of piperacillin into renal cysts.

Concentrations of piperacillin in the cystic fluid of eight patients with simple renal cysts were assessed after each patient had been given single or multiple doses of the antibiotic. Concentrations ranged from non-detectable to 9 mcg/ml.

Comparative nephrotoxicity and tissue accumulation of dactimicin, amikacin and gentamicin.

Dactimicin (ST 900) is a new pseudo-disaccharide aminoglycoside antibiotic which has been shown to be active against systemic infections in mice. Few data have so far been reported on dactimicin tissue accumulation or its potential nephrotoxicity. In this study, nephrotoxicity and renal tissue concentrations of gentamicin, amikacin and dactimicin were compared in Wistar rats. Liver, heart and lung accumulation of these drugs were also evaluated. Groups of 5 rats were respectively injected with 100 mg/kg body weight of the different drugs daily for 7 days. Five control rats were also injected with saline. Twenty-four hours after the last injection, all rats were sacrificed and bled to death. Blood samples were taken for BUN and serum creatinine assay. Kidney, liver, heart and lung tissues, as well as blood, were removed and processed for microbiological assay of gentamicin, amikacin and dactimicin. The results of this study showed that dactimicin, as well as amikacin, did not induce any significant increase in BUN and serum creatinine, while gentamicin administration resulted in severe uraemia in all rats. Consequently a much higher accumulation of gentamicin than amikacin and dactimicin was achieved in serum and tissues.

[Efficacy of enoxacin in the treatment of prostatitis-vesiculitis: its absence of toxicity on spermatogenesis]. / Efficacité de l'énoxacine dans le traitement des prostato-vésiculites: son absence de toxicité sur la spermatogénèse.

OBJECTIVES: The ability of enoxacin, a second generation quinolone, to diffuse into the seminal fluid both of normal volunteers (n = 10, protocol A) and patients with prostato-vesiculitis and positive sperm cultures (n = 10, protocol B) was investigated. In addition, the microbiological effectiveness and the occurrence of adverse effects on spermatogenesis were evaluated in the patient group. METHODS: Enoxacin was administered in oral doses of 300 mg b.i.d. for two and seven days to volunteers and patients, respectively. Two hours after the last drug administration, blood, semen and urine samples were collected to determine seminal fluid antibiotic concentrations by microbiological agar diffusion assay. In protocol B, sperm cultures and sperm analyses were performed at the end of treatment and repeated at 30 and 90 days follow-ups. RESULTS: In both protocols significant seminal fluid antibiotic concentration was achieved, thus providing evidence for considerable diffusion of the drug into prostate gland and seminal vesicles. Moreover, sperm cultures were sterile in all patients, and semen analysis demonstrated that spermatogenesis was not impaired by antibiotic treatment; on the contrary, 30 days after drug withdrawal percentage sperm motility improved, and the rate of abnormal forms decreased. CONCLUSIONS: The absence of adverse effects, both general and specifically on spermatogenesis, may be related to the restriction of indications and the brevity of the therapeutic cycles. Our results suggest that enoxacin may be successfully and safely used, in short term courses, for the treatment of documented genital tract infection by sensitive organisms. Further studies are needed to thoroughly evaluate the potential adverse effects on fertility of this quinolone, particularly when used for long-term suppressive therapy in patients with chronic urological infections.

[Current epidemiological and clinical aspects of tuberculosis: A study in the Hospital of Pisa]. / Attuali aspetti epidemiologici e clinici della tubercolosi: indagine nell'Ospedale di Pisa.

OBJECTIVES: To describe epidemiological and clinical features of tuberculosis (tbc) cases identified recently in the Pisa area (Tuscany, Italy). MATERIALS AND METHODS: We performed a retrospective study of all cases of tbc notified to the Public Health Service in Pisa during January 1996-December 1998. The diagnosis of tbc was made following the criteria of the Public Health Ministry. RESULTS: Eighty-eight patients affected by tbc were identified. Diagnosis was microbiologically proven (positive culture for M. tuberculosis) in 42 patients. Sixty-nine patients had pulmonary tbc, 14 extrapulmonary and 5 mixed tbc. Mean age was 56.4 years (range 16-87 years). Nineteen patients were extra European Community citizens. The incidence of tbc (N./100,000) was 8.4 in 1996, 10 in 1997 and 3.2 in 1998. In 5.7% of the cases tbc was associated with advanced HIV infection. The chest X-ray showed pleural effusion in 12 patients and cavitation in 26 patients. Fever was not present in 36.4% of the patients at the moment of diagnosis. 12% of the isolated strains of M. tuberculosis were in vitro multidrug-resistant. CONCLUSIONS: The data presented showed an important rate of tbc in Pisa, similar to the incidence of tbc reported by other studies carried out on a national scale. We have yet to understand if the decreased rate observed in 1998 represents a new trend. The isolation rate of multidrug-resistant strains of M. tuberculosis in Pisa seems higher than the rates reported in other geographical areas. Therefore monitoring of M. tuberculosis susceptibility to antimicrobial agents is necessary.

Dip-slide in patients at high risk of urinary tract infection.

146 initial and follow-up urine specimens of a urinary tract infection clinic were processed simultaneously by a dip-slide and by a standard pour plate method to evaluate the reliability of this simplified urine culture technique in a population with a high incidence of urinary tract infections. The dip-slide method gave false-negative results in only 8.7% of infected urines (greater than 10(5) cfu/ml urine), as determined by pour plate method. 1.3% false-positives were recorded. The false-negative rate rose to 22.2% when the dip-slide was used on the urines from patients on antimicrobial therapy. Our findings suggest that this simplified urine culture method is a useful tool even in populations with high incidence of urinary infections, although more careful evaluation of these test results is necessary when antimicrobial drugs are present in the urine specimens.

The influence of postural changes on the glomerular filtration rate in nephroptosis.

The influence of postural changes on renal function was determined in 13 patients with nephroptosis and in 5 normal subjects by measuring GFR in the erect and supine positions. The results indicate that GFR was reduced in the erect position in 10 of 13 patients with either unilateral or bilateral nephroptosis whereas GFR was increased in the erect position in 4 of 5 patients without renal disease. One patient with bilateral nephroptosis and renovascular hypertension was studied before and after surgical correction of his disease. These observations indicate that patients with nephroptosis may have significant reductions in renal function when they assume an upright position, and suggest that GFR measurements in the supine and erect position in patients with nephroptosis can be helpful in evaluating this disease.

Current microbiological and clinical aspects of urinary tract infections.

OBJECTIVES: To evaluate some risk factors which could affect the isolation rates of various uropathogens and their in vitro susceptibility to antibiotics in ambulatory and hospitalized patients. PATIENTS AND METHODS: A prospective study was conducted in a microbiological laboratory at Pisa Hospital. Nine-hundred and seventy-two consecutive patients with documented urinary tract infection were enrolled from April 1996 to October 1999. Data on age, sex, current or previous bladder catheterization, some underlying diseases as diabetes mellitus, and previous antibiotic therapy were recorded. The distribution of bacteria isolates and their in vitro susceptibility to antibiotics was evaluated. RESULTS: Escherichia coli was responsible for 54.7% of urinary tract infections. Isolation of E. coli is decreasing in comparison to previous observations, especially in males and in patients with indwelling bladder catheters who instead show higher Pseudomonas spp. and Enterococcus spp. isolation rates than females and non-catheterized patients. Diabetes mellitus does not affect the isolation rate of uropathogens and their patterns of susceptibility. Multivariate analysis of multiresistant uropathogens showed a positive significant correlation with indewelling bladder catheter and age. An upward trend in the resistance of E. coli to cotrimoxazole, ampicillin and fluoroquinolones was observed from 1996 to 1999; more than 50% of Pseudomonas spp. strains were resistant to fluoroquinolones and gentamicin. CONCLUSIONS: The empirical antibiotic therapy of patients with urinary tract infection should be guided by an accurate anamnesis evaluating not only age and sex but also the presence of a bladder catheter at the moment of urine collection or a history of recent bladder catheterization and previous courses of antimicrobial drugs.

Acute effects of tolamolol on renal function in hypertensive patients.

The renal heamodynamic effects of a single i.v. administration of tolamolol were studied in 9 hypertensive subjects. No change of GFR and ERPF was observed after tolamolol, while urine output decreased and urine creatinine concentration increased. A reduction of the heart rate was confirmed. Blood pressure was unchanged.

Urinary tract infection in diabetic patients.

AIM: The aim of the study was to compare the epidemiological, microbiological and clinical features of diabetic patients with urinary tract infection (UTI) to those of nondiabetic ones. METHODS: A prospective study was performed on 490 consecutive patients with proven UTI. The patients were studied on the basis of a specific questionnaire and hospital records. RESULTS: Of 490 enrolled patients, 89 (18.1%) had diabetes mellitus. The mean age of diabetics and nondiabetics was respectively 64.9 +/- 13.2 (SD) and 54.4 +/- 23.3 years. Most diabetics had asymptomatic bacteriuria and had undergone bladder catheterization more frequently than the nondiabetics. The most frequent causative agents of UTI in diabetics and nondiabetics were: E. coli (respectively, 56.1 vs. 56.8%), Proteus sp. (7.9% vs. 7.2%), Pseudomonas sp. (6.7 vs. 8.2%), Enterococcus sp. (6.7 vs. 7.2%). More than 50% of the isolated Pseudomonas sp. strains in both groups were resistant to gentamicin, piperacillin and norfloxacin. Both diabetics (52.8%) and nondiabetics (42.2%) had recurrent UTI during the follow-up period; the difference in the incidences did not reach statistical significance. CONCLUSION: No significant differences in epidemiological, clinical and microbiological evaluated features of diabetics and nondiabetics were pointed out, except for the higher frequency of bladder catheterization of diabetics than nondiabetics. However, the eradication of UTI seemed to be more difficult in diabetics than in nondiabetics.

Enterococcal glycopeptide resistance at an Italian teaching hospital.

Two thousand one hundred and thirteen strains of enterococci isolated at Pisa General Hospital in 1998 were analysed retrospectively to determine their glycopeptide resistance. Of all the microorganisms isolated in this period, 14.7% were enterococci (1405 Enterococcus faecalis, 19 Enterococcus faecium, six Enterococcus avium and 683 Enterococcus spp.). Two hundred and thirty (10.8%) of these enterococci were resistant or demonstrated reduced susceptibility to vancomycin and/or teicoplanin. The highest rate of resistance was found in outpatient enterococcal strains isolated from the urogenital tract. The frequency of enterococcal glycopeptide resistance at Pisa Hospital is higher than that reported from other areas of Italy.

Immunochemical and molecular characterization of vertebral hydatid fluid.

This study describes a 42-year-old male born in Tunisia, who presented with vertebral hydatidosis which was initially misdiagnosed as Pott's disease. The correct diagnosis was finally made utilizing CT and MRI imaging and confirmation of the diagnosis was made possible by molecular and immunochemical characterization of the content of vertebral cyst fluid.

Multicenter comparative study of aztreonam and gentamicin in the treatment of renal and urinary tract infections.

A multicenter comparative study was carried out to evaluate the efficacy of aztreonam and gentamicin in 186 patients with symptomatic renal or urinary tract infections. Patients were divided randomly into two groups: 94 patients received aztreonam 1 g/day intramuscularly and 92 patients received gentamicin 80 mg i.m. twice daily. The clinical and microbiologic results found a single daily dose of aztreonam to be more effective than gentamicin b.i.d. Furthermore, no evidence of side effects was seen with aztreonam. Such results are generally thought to ensure better compliance in outpatients.