Bacteremia associated with extracorporeal shockwave lithotripsy of gallbladder stones.

BACKGROUND/AIMS: The possible induction of bacteremia by extracorporeal shock wave lithotripsy (ESWL) of gallbladder stones was studied. MATERIALS AND METHODS: Seventy-six patients undergoing a total of 107 ESWL treatments were studied. RESULTS: Twenty-four (22%) of the 107 treatments were associated with bacteremia. Staphylococcus epidermidis was cultured during and/or after 23 (96%) of the treatments associated with bacteremia. The ESWL-induced tissue damage of the skin in the pass-way of the shock-waves was the most likely cause of bacteremia in these patients. There was no correlation between the occurrence of bacteremia and the age or body mass index of the patients. Neither was there any correlation of bacteremia related to the duration of the treatment, the number of shock waves, the energy delivered, the stone volume or the occurrence of calcified stones. No patient developed sepsis or endocarditis. Transient fever shortly after treatment was recorded in 5 patients (5%), one of whom had bacteremia. CONCLUSIONS: Routine antibiotic prophylaxis is not indicated in patients undergoing ESWL for gallbladder stones. The question whether such prophylaxis should be given to patients at special risk, for instance patients with artificial heart valves or known valvular heart disease, remains to be answered in larger controlled and randomized studies.

Meropenem versus imipenem/cilastatin in the treatment of intra-abdominal infections.

In order to compare the clinical and microbiological efficacy and safety of meropenem with imipenem/cilastatin, 249 patients with intra-abdominal infections participated in an open randomised comparative multicentre trial. Seventy-five men and 57 women (mean age 51 years) were enrolled in the meropenem group and 67 men and 50 women (mean age 52 years) in the imipenem/cilastatin group. The patients received either meropenem, 500 mg q 8 h, or imipenem/cilastatin, 500 mg/500 mg q 8 h by intravenous infusion for up to 17 days (mean 5 days). Ninety-seven of 99 patients (98%) receiving meropenem were clinically cured while 86 of 90 patients (96%) in the imipenem/cilastatin group were clinically cured. The microbiological response was satisfactory in 89 of 94 evaluable patients (95%) receiving meropenem and in 78 of 81 evaluable patients (96%) receiving imipenem/cilastatin. There was no significant difference in clinical and microbiological efficacy between the two treatment groups. Adverse reactions were noted in 26 patients receiving meropenem and in 36 patients receiving imipenem/cilastatin. The present study shows that meropenem is effective and well tolerated in the treatment of intra-abdominal infections.

Bacteremia following diagnostic and therapeutic ERCP.

The occurrence of bacteremia in association with diagnostic or therapeutic ERCP was studied in 180 patients undergoing a total of 194 examinations. Nineteen (15%) of 126 diagnostic procedures and 18 (27%) of 68 therapeutic procedures were associated with bacteremia (p less than 0.1). Nine patients had polymicrobial bacteremia and a total of 16 species were detected. Different streptococci, mainly alpha-hemolytic, were the most common bacteria which were identified in 38% of the bacteremic patients. There were no significant differences with regard to the occurrence of fever, pancreatitis, or septic complications between the diagnostic and therapeutic groups of patients. Neither did the complication rate in patients with bacteremia differ from that in patients without bacteremia, whether the procedure was diagnostic or therapeutic. Complication rates did not differ between patients with and patients without pancreaticobiliary obstruction. However, the majority of patients with biliary stasis had drainage with relief of the obstruction at the time of the diagnostic ERCP. We conclude that general routine antibiotic prophylaxis is not indicated in patients undergoing diagnostic or therapeutic ERCP. The question whether such prophylaxis should be given with certain diagnoses or treatments, or in patients with valvular heart disease, remains to be answered in controlled randomized studies.

Short-term cefotaxime prophylaxis reduces the failure rate in lower limb amputations.

The effect of prophylaxis with a broad-spectrum antibiotic agent in lower limb amputations was studied in a prospective, randomized investigation of 38 patients. Nineteen received cefotaxime (Claforan) and 19 served as controls. Three patients died in the immediate post-operative period. In the treatment group, 15/18 healed compared with 10/17 controls (P less than 0.001). We concluded that short-term cefotaxime prophylaxis increases the chances to achieve good stump healing.

Bioluminescent assay of bacterial ATP for rapid detection of bacterial growth in clinical blood cultures.

A bioluminescent assay of bacterial ATP for rapid detection of bacterial growth in 512 clinical aerobic blood cultures was evaluated. At the detection limit of bacterial ATP (10(-10) mol/l) in the blood cultures 94.2% of the true positive blood cultures were detected (sensitivity) and the specificity was 85.8%. If the cut-off limit was increased the sensitivity decreased and the specificity increased and at 2 x 10(-9) mol/l ATP the maximum correctly classified blood cultures was reached. At this cut-off limit the sensitivity was 82.9% and the specificity was 99.6%. In 54.3% of the true positive blood cultures bacterial growth was detected more rapidly with the bioluminescent assay than with macroscopic examination and subculture.

A clinical and epidemiological study of "ornithosis" caused by Chlamydia psittaci and Chlamydia pneumoniae (strain TWAR).

Ornithosis is a notifiable disease in Sweden since 1954. In 1981 and 1982 a sharp increase in the number of notifications occurred. Since then the number has declined but is still high. A changed epidemiology characterized by no history of bird contact and no common source, raised the suspicion of a new agent. Serological data now suggest that the epidemic was to a substantial part due to Chlamydia pneumoniae (strain TWAR) (48% of the patients during 1981-1982 compared to 9% during 1984-1987). During recent years TWAR infections have thus become uncommon but reappearance can be expected in the near future. The clinical picture as well as the complications appear to be very similar in infections caused by C. pneumoniae and C. psittaci.

Rapid susceptibility testing of Mycobacterium tuberculosis by bioluminescence assay of mycobacterial ATP.

Mycobacterial growth was monitored by bioluminescence assay of mycobacterial ATP. Cultures of Mycobacterium tuberculosis H37Rv and of 25 clinical isolates of the same species were exposed to serial dilutions of ethambutol, isoniazid, rifampin, and streptomycin. A suppression of ATP, indicating growth inhibition, occurred for susceptible but not resistant strains within 5 to 7 days of incubation. Breakpoint concentrations between susceptibility and resistance were determined by comparing these results with those obtained by reference techniques. Full agreement was found in 99% of the assays with the resistance ratio method on Lowenstein-Jensen medium, and 98% of the assays were in full agreement with the radiometric system (BACTEC). A main advantage of the bioluminescence method is its rapidity, with results available as fast as with the radiometric system but at a lower cost and without the need for radioactive culture medium. The method provides kinetic data concerning drug effects within available in vivo drug concentrations and has great potential for both rapid routine susceptibility testing and research applications in studies of drug effects on mycobacteria.

Direct membrane-damaging effect of ketoconazole and tioconazole on Candida albicans demonstrated by bioluminescent assay of ATP.

Bioluminescent assays of fungal ATP in cultures of Candida albicans exposed to tioconazole and ketoconazole demonstrated that intracellular ATP levels were directly related to cell viability. At high concentrations of drug, a fungicidal effect was indicated by a very rapid and heavy leakage of ATP and a simultaneous, dramatic decrease in intracellular ATP. This leakage was due to direct membrane damage, which was less pronounced after exposure to ketoconazole than to tioconazole. After exposure to lower imidazole concentrations, intracellular ATP indicated growth inhibition without significant leakage of ATP. These findings support the hypothesis that imidazole antifungal agents basically act in the same manner but at different concentrations.

Rapid detection of bacterial growth in blood cultures by bioluminescent assay of bacterial ATP.

A method for rapid detection of bacterial growth in blood cultures by bioluminescent assay of bacterial ATP was developed. Samples from blood cultures were treated with a blood-lysing detergent combined with an ATP-hydrolyzing enzyme to destroy blood cell ATP. Blood cell ATP which was bound to cell debris and escaped the ATPase activity was then separated from the bacteria on Percoll density gradients. Bacterial ATP from the bacterial layer was determined by the firefly bioluminescence system. In simulated blood cultures inoculated with 10 CFU of bacteria per ml of blood, bacterial ATP levels exceeded the detection limit (10(-10) M) after 6 to 10 h of incubation. This ATP level corresponds to approximately 10(4) CFU of bacteria per ml.

Firefly luciferase ATP assay as a screening method for bacteriuria.

A rapid (15 min) test for bacteriuria based on firefly luciferase analysis of bacterial ATP has been evaluated in 2,018 clinical urine specimens. The test procedure involves removal of nonbacterial ATP by treatment of urine with Triton X-100 and apyrase, extraction of bacterial ATP by boiling, and bioluminescent analysis of bacterial ATP by firefly luciferase, using a luminometer. For comparison, the widely used nitrite test was included in the study as an example of an alternative rapid chemical test. The test was set up to distinguish between specimens yielding greater than 10(5) CFU/ml and specimens yielding less than 10(5) CFU/ml. A level of 13.5 nM ATP was chosen to define the limit between negative and positive results. At this discriminatory level, 92% of specimens yielding greater than 10(5) CFU/ml and 88% of specimens yielding less than 10(5) CFU/ml were correctly classified with the luciferase method, whereas corresponding figures for the nitrite test were 55 and 99%, respectively. Of the 12% false luciferase positives, 20% were shown to contain greater than 10(5) CFU/ml on prolonged incubation, thus reducing the false-positive rate to 10%. Of the 8% false luciferase negatives, 65% had low levels of CFU in the range of 10(5) to 10(6).

Inhibition of aminoglycoside activity in heparin.

Measurements of aminoglycosides by an agar disk diffusion assay are inhibited by heparin in a dose-dependent way. When assayed by a homogeneous immunoassay, this was only evident for tobramycin. This indicates that specimens for aminoglycoside measurement should not be obtained in heparinized tubes. When heparin is used clinically as an anticoagulant, the amount in blood does not reach levels that affect the aminoglycoside activity.

Benign meningococcemia in childhood. A report of five cases with clinical and diagnostic remarks.

Five children aged 1/2--10 years with benign meningococcemia are reported. The clinical picture was quite uniform: good general condition, spikes of fever, skin eruptions as maculopapules--sometimes haemorrhagic, appearing in association with febrile periods, and arthralgia (big joints). The diagnosis involves either isolation of meningococci (MC) from blood, demonstration of MC with immunofluorescence in skin eruptions, or a significant elevation of MC antibody titre in connection with typical clinical signs and symptoms. Important differential diagnoses are Henoch-Schönlein syndrome, disseminated gonococcal infection, septicemia of other origins, subacute bacterial endocarditis, viral infections, hypersensitivity reactions and subsepsis allergica. By co-agglutination technique, the causative agent of meningococcemia in 4 of the 5 children was shown to be MC group B. These have some features in common with gonococci, whereby an incorrect diagnosis might be suggested as demonstrated in one of our patients. The question is raised whether MC group B is the main causative agent in benign meningococcemia.

Pathogenicity in mice of strains of Candida albicans with different in vitro sensitivity to 5-fluorocytosine.

The pathogenicity in mice of 7 strains of Candida albicans with different in vitro susceptibility to 5-fluorocytosine (5-FC) was investigated. Resistant strains were not less virulent than susceptible strains. This is contradictory to findings reported for candida strains resistant to polyene antibiotics, which were less pathogenic than susceptible strains. The implications of these findings are discussed.

Septicemia and meningitis caused by Fusobacterium aquatile.

A case of septicemia and meningitis caused by Fusobacterium aquatile is described. The insidious onset of the megningitis and occurrence of multiple cranial nerve affections were outstanding features. In spite of adequate antibiotic treatment the course was protracted, and the outcome was permanent damage to 3 of the affected cranial nerves.

Effects of ampicillin on intracellular levels of adenosine triphosphate in bacterial cultures related to antibiotic susceptibility.

Short time effects of ampicillin on viability and levels of intracellular ATP were studied in bacterial cultures and a close relationship between intracellular ATP levels and viability was demonstrated. The connection between the effects observed and MIC values is discussed. The possibility of using the phenomenon for rapid antibioitc susceptibility testing was studied in clinical isolates incubated for 2 hours followed by luciferase assay of intracellular ATP. A positive correlation was demonstrated between ampicillin-induced decreases in intracellular ATP and inhibitory zone diameters, as measured by the agar diffusion technique.

A rapid semiautomated bioassay of gentamicin based on luciferase assay of bacterial adenosine triphosphate.

A rapid semiautomated bioassay of gentamicin in serum based on the effect of gentamicin on intracellular adenosine triphosphate (ATP) levels in bacterial cultures is presented. The ATP assay was performed with the firefly luciferin/luciferase system and results were compared with an agar diffusion technique. The lower limit of detection was set at 1 microgram/ml. The accuracy of the ATP assay expressed as a recovery of gentamicin over the range 1--8 microgram/ml was 98--103% and S.D. varied between 11-15%. The reproducibility was approximately within the same limits. Other antibiotics tested did not interfere with the determination of gentamicin. 112 clinical serum specimens containing gentamicin alone (N = 55) or in combination with other antibiotics (N = 57) were assayed and results with the two methods compared (r = 0.94). Volumes required were 0.1 ml serum and results were available within 3 h.

Haemophilus parainfluenzae infection of the central nervous system. A report on two infants.

Two cases of infection of the central nervous system (CNS) with Haemophilus parainfluenzae--a 12-month-old girl with meningitis and a 17-month-old girl with brain abscess--are reported. Both infants had long-standing upper respiratory infection before CNS disease. Both recovered after treatment.

In-vitro effect of doxycycline on levels of adenosine triphosphate in bacterial cultures. Possible clinical applications.

Short-term effects of doxycycline on viability and levels of intracellular ATP in bacteria were studied. Inhibition of growth by doxycycline was reflected in a corresponding inhibition of the accumulation of intracellular ATP which was clearly demonstrable within 1-2 hours. The effects of doxycycline on intracellular ATP were dose-dependent and the use of ATP assays for quantitation of antibiotics in serum is discussed. In 45 clinical isolates exposed to doxycycline a positive correlation was found between antibiotic-induced inhibition of intracellular ATP levels and inhibitory zone diameters with the disc diffusion method, indicating possible clinical applications in rapid susceptibility testing.