Changing trends in frequency and antimicrobial resistance of urinary pathogens in outpatient clinics and a hospital in Southern Israel, 1991–1995

In order to monitor changes in the frequency and antimicrobial resistance of urinary pathogens over several years, urinary cultures received from outpatient clinics and from a hospital during a period of one month each in 1991 and 1995 were analyzed at a clinical microbiology laboratory. In 1991 and 1995, 1366 and 1534 significant monomicrobic cultures respectively were reviewed. The frequency ofEscherichia coli dropped significantly in the outpatient clinics from 70.5% to 61.2% (p<0.0001). The frequency ofProteus mirabilis, Morganella morganii, Pseudomonas aeruginosa and other gram-negative bacteria also decreased, but the frequency ofKlebsiella spp. andEnterobacter spp. increased from 2.6% to 5.8% (p<0.0001). In the hospital, the frequency ofEnterobacter spp. (p<0.04),Escherichia coli andMorganella morganii declined from 1991 to 1995, whereas the frequency ofPseudomonas aeruginosa (p=0.001),Acinetobacter spp. (p<0.05),Klebsiella spp.,Proteus mirabilis and other gram-negative rods increased considerably. The frequency of gram-positive aerobic bacteria rose markedly in outpatient specimens from 6.1% to 13.5% (p<0.0001), while a decline from 14.4% to 9.3% was noted in hospital specimens (p<0.02). A significant rise in the resistance ofEscherichia coli to gentamicin and ciprofloxacin (p<0.0001) was detected in outpatient isoates. In the hospital, gram-negative urinary pathogens demonstrated increased resistance to ampicillin (p=0.042), cefuroxime (p=0.005), gentamicin (p=0.002) and ciprofloxacin (p<0.0001) during the study period. The changing etiology of urinary tract infections and the increasing resistance of organisms indicate that periodic monitoring and possibly also modification of empirical therapy are required.     

Pharmacokinetic dosing of aminoglycosides: a controlled trial

PURPOSE: To evaluate whether individualized pharmacokinetic dosing of aminoglycosides can reduce nephrotoxicity and improve the outcome of patients with gram-negative sepsis. METHODS: We conducted a prospective controlled trial at a tertiary care university hospital. Eighty-one patients with suspected or documented gram-negative infections were enrolled. All were treated with either gentamicin or amikacin, according to clinical judgement. Patients were allocated to one of two groups based on the last digit (odd/even) of their identification number. In the study group (pharmacokinetic dosing) of 43 patients, plasma aminoglycoside levels were determined 1 hour after initiation of drug infusion and 8 to 16 hours later to estimate the elimination half-life and volume of distribution, from which the subsequent dosage schedule was calculated. Target peak plasma levels were 20 microg/mL for gentamicin and 60 microg/mL for amikacin. Target trough levels were <1 microg/mL for both drugs. The control group (fixed once-daily dosing) consisted of 38 patients who were prescribed single daily doses of gentamicin or amikacin. The primary endpoints were renal toxicity (> or = 25% increase in serum creatinine level or a serum creatinine level > or = 1.4 mg/dL) and 28-day mortality. RESULTS: The two study groups were similar in age, sex, indications for therapy, Acute Physiology and Chronic Health Evaluation (APACHE) II score, and clinical assessment at baseline. Although the pharmacokinetic group received significantly greater doses of aminoglycosides than did the once-daily group, the incidence of nephrotoxicity was significantly lower in the pharmacokinetic group (5% [2/43] vs. 21% [8/38], P = 0.03). There was no statistically significant difference in 28-day mortality (27% [12/43] vs. 22% [8/38], P = 0.3). CONCLUSION: These results suggest that individualized pharmacokinetic dosing of aminoglycosides reduces the incidence of nephrotoxicity and allows the use of greater doses of aminoglycosides.     

Septic arthritis due to bacteroides fragilis after pilonidal sinus resection in a patient with rheumatoid arthritis

Summary Bacteroides fragilis is a rare cause of septic arthritis. Most patients with B.fragilis septic arthritis have a chronic joint disease, particularly rheumatoid arthritis, and sources of infection are lesions of the gastrointestinal tract and the skin. We report a 69-year-old male, who developed B.fragilis septic arthritis after pilonidal sinus resection. High level of suspicion of development B.fragilis septic arthritis must be present in patients with chronic joint disease in whom gastrointestinal or skin surgery was previously performed.     

Incidence and clinical significance of bacteremia and sepsis among cardiac patients treated with intra-aortic balloon counterpulsation pump

In this prospective study, a significant incidence of fever (47%), true bacteremia (15%), and sepsis (12%), were found in 60 cardiac patients treated with an intra-aortic balloon counterpulsation pump. The benefit of antibiotic prophylaxis in this setting should therefore be evaluated.     

Inhibition of superoxide production in human neutrophils by combinations of heparin and thrombolytic agents.

OBJECTIVE--To investigate the effect of heparin and thrombolytic agents on superoxide generation by human neutrophils, as inhibition of superoxide production may have a role in reducing ischaemia and reperfusion injury. METHODS--Neutrophil superoxide production stimulated by phorbol myristate acetate (PMA), opsonised zymosan, or formyl methionyl leucyl phenylalanine (FMLP) was measured as the superoxide dismutase inhibitable reduction of acetyl ferricytochrome c by a microtitre plate technique. RESULTS--Heparin, at concentrations of 0.5-500 U/ml, caused a gradual inhibition of superoxide production stimulated by PMA, opsonised zymosan, or FMLP. Tissue plasminogen activator was more potent than heparin in inhibiting superoxide production induced by opsonised zymosan or FMLP, but it did not affect the activity stimulated by PMA. Streptokinase or urokinase had no effect on superoxide production. When heparin was used in combination with tissue plasminogen activator, streptokinase, or urokinase at their therapeutic concentrations there was a significant inhibition of superoxide generation (70%, 30%, and 25%, respectively). The therapeutic concentrations of tissue plasminogen activator alone caused a reduction of 40% of neutrophil superoxide production. When tissue plasminogen activator and streptokinase were both added to neutrophils, however, a synergistic inhibition of 80% was achieved. CONCLUSIONS--The inhibition of super oxide generation by these drug combinations may explain the limited inflammatory response and reduction of reperfusion injury observed in patients receiving thrombolytic treatment.     

Intrauterine restriction (IUGR)

Perinatal mortality and morbidity is markedly increased in intrauterine growth restricted (IUGR) fetuses. Prenatal identification of IUGR is the first step in clinical management. For that purpose a uniform definition and criteria are required. The etiology of IUGR is multifactorial and whenever possible it should be assessed. When the cause is of placental origin, it is possible to identify the affected fetuses. The major complication is chronic fetal hypoxemia. By monitoring the changes of fetal vital functions it is thus possible to improve both management and outcome. The timing of delivery is crucial but the optimal management scheme has not yet been identified. When IUGR is identified at very early gestational ages, serial assessments of the risk of continuing the in utero fetal life under adverse conditions versus the risks of the prematurity should be performed. Delivery of IUGR fetuses should take place in centers where appropriate neonatal assistance can be provided. Careful monitoring of the IUGR fetus during labor is crucial as the IUGR fetus can quickly decompensate once uterine contractions have started.     

Urinary Tract Infections Caused by Multi-Drug Resistant <Emphasis Type="Italic">Proteus mirabilis</Emphasis>: Risk Factors and Clinical Outcomes

Background:   

Proteus mirabilis (PM) as well as other membersof the Enterobacteriaceae family are a leading cause ofinfectious diseases in both the community and acute caresettings. The prevalence of multi-drug resistant (MDR) bacterialisolates have increased in the last few years, affectingthe prognosis and survival of hospitalized patients. The aimof our study was to determine the risk factors and clinicaloutcomes of urinary tract infections (UTIs) caused by MDR PMin patients hospitalized in our institution.     

Technetium Tc 99m diphosphonate bone scan. False-normal findings in elderly patients with hematogenous vertebral osteomyelitis

Hematogenous osteomyelitis is usually diagnosed by an abnormal technetium Tc 99m diphosphonate bone scan in symptomatic patients who have positive blood cultures. False-normal 99mTc bone scans have been described recently in neonates with biopsy-proved osteomyelitis. This phenomenon seems to be extremely rare in adults. Two elderly patients with hematogenous vertebral osteomyelitis had normal technetium Tc 99m diphosphonate bone scans when first evaluated. In both cases the bone scans became abnormal four to six weeks after onset of symptoms and two to four weeks after the initial normal results of the study. When suggested by the clinical picture, hematogenous osteomyelitis cannot be ruled out by a normal 99mTc bone scan at any age. Gallium scan, computed tomographic scan, or bone biopsy can be helpful in such cases.