[Azlocillin plus amikacin: an alternative therapy for sepsis caused by resistant staphylococci?]. / Azlocilina y amikacina: Una alternativa terapéutica para la septicemia por estafilococos resistentes?

OBJECTIVE: To assess the effectiveness of combined therapy with azlocillin and amikacin in a group of neonates with sepsis caused by multiresistant staphylococci who were hospitalized in the neonatal intensive care unit of Hospital Ginecobstétrico "America Arias" in Havana, Cuba, from 1998 to 2000. METHODS: A retrospective study was carried out of the clinical and laboratory results obtained in 15 patients with sepsis caused by multiresistant staphylococci who received combined therapy with azlocillin and amikacin, according to hospital guidelines on the use of antibiotics. We used a broth microdilution method to study the patterns of resistance shown by isolated strains to 10 of the antibiotics in use. In vitro synergy tests, specifically the checkerboard technique with microtitration plates, were used to observe the effects of treatment in 8 patients. RESULTS: Twelve coagulase-negative staphylococci and three Staphylococcus aureus isolates showed five different patterns of resistance on the basis of their sensitivity to oxacillin, three aminoglycosides, and vancomycin. Six of the synergy tests showed a considerable synergistic effect, with an average three-fold reduction in the minimum inhibitory concentrations (MIC) of the two antibiotics used to treat the patients. No antagonistic effects were noted, and the combined antibiotics showed an overall clinical effectiveness of 91.7%. CONCLUSIONS: The test showed that the therapeutic combination used was effective, but further studies are needed before conclusive results are obtained.

Once-daily versus multiple-daily gentamicin in empirical antibiotic therapy of febrile neutropenia following intensive chemotherapy.

The clinical efficacy and toxicity of once-daily compared with multiple-daily gentamicin dosing, in combination with azlocillin, were studied retrospectively in febrile neutropenic episodes following intensive chemotherapy. Fifty-two episodes were studied in 28 patients with acute myeloid leukaemia. Reasons for initiation of antibiotic therapy, dose, duration of treatment, organism isolation rates, response, cost comparison and toxicity were studied in the two treatment groups. The main indication for initiation of antibiotic therapy was neutropenic fever without a documented infection (80.8% of episodes). The response rate to once-daily gentamicin dosing and azlocillin was three times higher than to multiple-daily gentamicin dosing and azlocillin (P = 0.0112). The incidence of toxicity was low overall and was slightly but not significantly higher in the once-daily group. In this clinical context once-daily gentamicin at a dose of 7 mg/kg/day is more effective than a multiple-daily dosing regimen but may be more toxic.

Comparison of a beta-lactam alone versus beta-lactam and an aminoglycoside for pulmonary exacerbation in cystic fibrosis.

UNLABELLED: We determined whether a beta-lactam and an aminoglycoside have efficacy greater than a beta-lactam alone in the management of a pulmonary exacerbation in patients with cystic fibrosis. STUDY DESIGN: Azlocillin and placebo or azlocillin and tobramycin were administered to 76 patients with a pulmonary exacerbation caused by Pseudomonas aeruginosa in a randomized double-blind, third-party monitored protocol. Improvement was assessed by standardized clinical evaluation, pulmonary function testing, sputum bacterial density, sputum DNA content, and time to the next pulmonary exacerbation requiring hospitalization. RESULTS: No significant difference was seen between the 2 treatment groups in clinical evaluation, sputum DNA concentration, forced vital capacity, forced expiratory volume in second 1, or peak expiratory flow rate at the end of treatment (33 receiving azlocillin alone and 43 both antibiotics); adverse reactions were equivalent in each group. Sputum P. aeruginosa density decreased more with combination therapy (P =.034). On follow-up evaluation, an average of 26 days after the end of treatment, all outcome indicators had worsened in both groups. Time to readmission for a new pulmonary exacerbation was significantly longer in the group receiving azlocillin plus tobramycin (P <.001). Treatment-emergent tobramycin resistance occurred in both groups and was more frequent with combination therapy. CONCLUSION: We conclude that the combination of a beta-lactam and an aminoglycoside produces a longer clinical remission than a beta-lactam alone and slightly better initial improvement.

Pseudomonas aeruginosa infection in embryonated hen's eggs. An alternative in vivo model for the screening of antibacterial substances.

Embryonated hens' eggs can be reliably infected by Pseudomonas aeruginosa in laboratory experiments. Therapy tests with the antibiotics azlocillin (CAS 37091-66-0) and gentamicin (CAS 13291-74-2) on this type of infected hens' eggs demonstrate that this test system offers a realistic alternative to septic experiments with small laboratory rodents. Chick embryos survive a lethal Pseudomonas infection when azlocillin or gentamicin in a relevant therapeutic dose are administered immediately after the infective agent. The use of Pseudomonas infected chick embryos in the screening for new antiinfectives allows, therefore, a considerable reduction of the number of laboratory rodents required.

Ciprofloxacin resistant Serratia marcescens endocarditis as a complication of non-Hodgkin's lymphoma.

We report a case of endocarditis caused by a ciprofloxacin-resistant strain of Serratia marcescens in a 50-year-old female neutropenic patient with non-Hodgkin's lymphoma which occurred while receiving ciprofloxacin prophylaxis. She made poor progress on first line therapy with azlocillin and gentamicin by bolus injection t.d.s. The infection was finally eliminated by a regimen of continuous infusion of azlocillin and once daily gentamicin.

[Pulmonary aspergillosis in an immunocompetent female patient]. / Pulmonale Aspergillose bei einer immunkompetenten Patientin.

Symptoms of bronchopneumonia developed over 4 months in a 63-year-old woman in previously good health. The symptoms worsened despite treatment with tetracycline (500 mg twice daily for 10 days). Middle-lobe pneumonia was diagnosed both clinically and radiologically, but monotherapy with ofloxacin (200 mg twice daily) was ineffective, as well as combined treatment with gentamycin (80 mg), oxacillin (1 g) and azlocillin (5 g), each three times daily intravenously. Bronchoscopy revealed obstruction of the lumen of the right middle lobe bronchus by viscous purulent secretion which contained a high count of Aspergillus fumigatus, previously found in several sputum samples. The inflammatory process regressed completely within 12 days on itraconazole (200 mg twice daily), combined with nystatin inhalation (100,000 IU five times daily). The only possible aetiologically significant risk factor in this immunocompetent woman could have been her frequent use of a bio-waste container.

In vitro evaluation of newer beta-lactam antibiotics against gram negative bacilli isolated from neutropenic patients.

The in-vitro susceptibility pattern to newer beta lactams namely Ticer/Clav, Azlocillin, Piperacillin and Imipenem was determined with 50 clinical strains isolated from neutropenic patients with strains isolated from neutropenic patients with sepsis, with an objective of evolving a strategy for empirical antibiotic therapy for febrile neutropenic patients. The MIC90 value for Imipenem for the Gram negative bacilli tested, other than Pseudomonas was < 0.25 mcg/ml therapy revealing a high degree of susceptibility, while for Ps. aeruginosa and related species MIC50 and MIV90 values were 2.0 and 64.0 micrograms/ml respectively. A comparatively lower degree of susceptibility was found among Gram negative bacilli included in the study to ticar/clavu, azlocillin and piperacillin indicating a moderate degree of resistance to these antibiotics. The data from this study suggests that (i) Ureidopenicillins with an aminoglycoside should be effective therapy for proven Pseudomonas and other Gram negative sepsis in febrile neutropenic patients. (ii) Imipenem would be the antibiotic of choice in Gram negative bacterial sepsis in febrile neutropenic patients where the organism is resistant to cephalosporins and ureidopenicillins.

[Therapeutic effect of azlocillin and its combinations with other antibiotics in experimental plague infection]. / Lechebnoe deistvie azlotsillina i ego sochetanii s drugimi antibiotikami pri éksperimental'noi chume.

The therapeutic effect of azlocillin and its combinations with other antibiotics was studied in a model of experimental plague of albino mice. Azlocillin was shown to be efficient in the prophylaxis and treatment of the experimental plague infection. The optimal doses of azlocillin were determined. The protective action of the drug depended on the dose and the time of its administration. The therapeutic effect was mainly defined by the antibiotic dose. The use of azlocillin in not sufficiently active doses in combination with aminoglycosides (gentamicin, sisomicin and amikacin), rifampicin or doxycycline significantly increased the percentage of the animal survival by comparison with that after the use of every antibiotic alone. A synergistic effect was observed when azlocillin was used in combination with rifampicin or amikacin.

A randomized trial of high-dose ciprofloxacin versus azlocillin and netilmicin in the empirical therapy of febrile neutropenic patients.

A prospective, randomized trial comparing monotherapy with high-dose ciprofloxacin versus a standard combination regimen of azlocillin and netilmicin in the empirical treatment of febrile episodes in neutropenic patients was performed. One hundred and forty-six patient episodes were randomized, but ten (seven ciprofloxacin and three azlocillin/netilmicin) were considered unevaluable for efficacy, and three episodes were withdrawn due to incorrect randomization or non-neutropenia. Of the remaining 133 episodes, infections resolved without modification of therapy in 25/66 (38%) versus 28/67 (42%) of ciprofloxacin and azlocillin/netilmicin treated groups respectively (P = 0.72). Considering all randomized episodes, therapy was modified in 46/73 (63%) episodes with ciprofloxacin and 39/70 (56%) with azlocillin/netilmicin (P = 0.40). Of 73 patient episodes randomized to ciprofloxacin, 25 (34%) received oral follow-on therapy after a median of three days of intravenous therapy. Infections were microbiologically documented in 31/73 (42%) ciprofloxacin and 32/70 (46%) azlocillin/netilmicin, of which 8/27 (30%) and 14/31 (45%) of evaluable episodes resolved without modification of therapy respectively (P = 0.28). Gram-positive organisms accounted for 78% of all organisms cultured with 36% coagulase-negative staphylococci. Bacteriological eradication was recorded in 18/24 (75%) and 26/29 (90%) evaluable patient episodes treated with ciprofloxacin and azlocillin/netilmicin respectively (P = 0.27). Superinfections were seen in 14% of episodes in both groups, and subsequent infections in 12% ciprofloxacin and 14% azlocillin/netilmicin treated patients. Two patients (one ciprofloxacin and one azlocillin/netilmicin) died within 48 h of randomization, and a further 13 patients (four ciprofloxacin and nine azlocillin/netilmicin) died before resolution of neutropenia. Adverse events were recorded in 9% and 15% of ciprofloxacin and azlocillin/netilmicin treated patients respectively, with skin rash (five ciprofloxacin and four azlocillin/netilmicin), nephrotoxicity (two azlocillin/netilmicin), abnormal liver function tests (two azlocillin/netilmicin), ototoxicity (one azlocillin/netilmicin) and nausea (one ciprofloxacin) being the major events recorded. It was concluded that monotherapy with ciprofloxacin at this dosage is a safe alternative to combination therapy with azlocillin/netilmicin, and has the advantages of twice daily administration, iv and oral presentations, no cross allergy in beta-lactam-hypersensitive patients, and no nephro- or oto-toxicity.

Molecular epidemiological analysis of Pseudomonas aeruginosa strains causing failure of antibiotic therapy in cystic fibrosis patients.

A combination of esterase electrophoretic typing and analysis of the restriction fragment length polymorphism of ribosomal DNA regions (ribotyping) was used to compare 27 Pseudomonas aeruginosa strains isolated before and after two-week courses of anti-pseudomonal treatment in seven cystic fibrosis patients. A total of 12 courses of therapy were studied in which ciprofloxacin, ceftazidime, azlocillin or imipenem were used alone or in combination with tobramycin. Isolates at a count of greater than or equal to 10(6) cfu/ml of sputum were collected when there was evidence of therapeutic failure on the basis of persistence of isolates whether or not they were resistant to the antibiotic used for therapy. Emergence of resistance was observed in ten cases and failure to eradicate sensitive strains in five cases. Among the 27 isolates, eight zymotypes and five ribotypes were identified. With this typing approach, resistant post-therapy isolates were found to be identical to pre-therapy isolates in all cases but one. However, in one case an additional resistant strain was isolated after therapy besides that initially present. In all five cases in which susceptibility was still observed after treatment, pre-therapy and post-therapy isolates were indistinguishable. Using this molecular typing approach, all the strains were typable. Thus combination of esterase typing and ribotyping should improve the analysis of therapeutic failure in cystic fibrosis patients.

[Chemotherapy of Pseudomonas aeruginosa infections in children during the first three months of life]. / Khimioterapiia detei pervykh trekh mesiatsev zhizni s sinegnoinoi infektsiei.

The data on the efficacy of antibacterial drugs and their combinations in treatment of 150 three-month old infants with generalized infection due to Pseudomonas aeruginosa are presented. The clinical isolates of P. aeruginosa were found to be carriers of multiple drug resistance which markedly complicated the chemotherapy. Only combined antibacterial therapy of such infants proved to be rational. High activity of aminoglycosides, azlocillin and cefotaxime against P. aeruginosa and the synergistic action of their combinations observed in the patients permitted to recommend the use of combinations of the above drugs in the empirical chemotherapy.

Adverse reactions to prolonged treatment with high doses of carbenicillin and ureidopenicillins.

Charts were reviewed for 63 patients whose chronic pseudomonas osteomyelitis was treated with high doses of extended-spectrum penicillins for prolonged periods. The incidence of untoward drug reactions was significantly higher than expected. Carbenicillin evoked adverse reactions in 22.8% of patients. However, most of these reactions were mild, and a change of drug was required in only 5.7% of cases. No adverse drug reactions were observed with cumulative doses of less than 750 g. In contrast to carbenicillin, the ureidopenicillins were associated with adverse reactions in 67.7% of patients; most reactions were moderate to severe in intensity; a cumulative dose of greater than 250 g produced adverse reactions; and discontinuation or change of therapy was required in 51.6% of cases. The main adverse reactions to both carbenicillin and the ureidopenicillins included rash, drug fever, leukopenia, eosinophilia, thrombocytopenia, and hepatic damage.

Randomized multicentre study of ciprofloxacin and azlocillin versus gentamicin and azlocillin in the treatment of febrile neutropenic patients.

In a randomized multicentre study ciprofloxacin combined with azlocillin was compared with gentamicin and azlocillin for the treatment of febrile episodes in neutropenic patients. In 147 evaluable episodes in 108 patients, 80 patients received ciprofloxacin/azlocillin and 67 received gentamicin/azlocillin. The two treatment groups were comparable in terms of age, underlying diagnosis, and duration of neutropenia. Microbiologically documented infections were the cause of fever in 34 (42.5%) and 29 (43.3%) episodes in the ciprofloxacin/azlocillin and gentamicin/azlocillin groups respectively. At the end of therapy, 46 patients (57.5%) receiving ciprofloxacin/azlocillin showed complete resolution compared with 30 (44.7%) for the gentamicin/azlocillin group (P = 0.14). The clinical response rate for microbiologically documented episodes was 58.8% and 48.3% respectively (P = 0.45). Among the microbiologically documented infections with follow-up cultures available, 24 (92.3%) of 26 isolates from patients receiving ciprofloxacin/azlocillin were eradicated, in comparison with 19 (86.4%) of 22 in the gentamicin/azlocillin group (P = 0.65). There were five superinfections, all in the gentamicin/azlocillin group. Significant resistance to the study drugs was not seen. Of all evaluable patients, including those subsequently withdrawn because of early modification of therapy, there were 12 deaths within the study period; six (6.8%) of these occurred in 88 patients randomized to the ciprofloxacin/azlocillin group, compared with two of 80 (2.5%) in the gentamicin/azlocillin group. Both treatments were generally well-tolerated; one patient in the ciprofloxacin/azlocillin group developed convulsions, probably related to ciprofloxacin. The combination of ciprofloxacin and azlocillin is as effective as gentamicin plus azlocillin and offers a useful alternative for the empirical treatment of febrile neutropenic patients.

[Perioperative antimicrobial prophylaxis in Obwegeser-Dal Pont surgery for prognathism]. / Perioperative antimikrobielle Chemoprophylaxe bei Progenieoperationen nach Obwegeser-Dal Pont.

The value of ultra short antimicrobial prophylaxis using azlocillin in preventing postoperative wound infections was studied in a prospective clinical/bacteriological study in 41 orthognathic operations. Preoperatively the oral mucosa and pharyngeal flora of each patient was subjected to bacteriological identification with particular emphasis on anaerobes and sensitivity tests for organisms with established pathogenic potential. The results of a bacteriological examination of the redon drains on day 1 postoperatively indicated a contamination of the surgical wound. Clinically 31 patients showed moderate postoperative edema of the buccal soft tissues and 10 patients had hematomas or hemorrhages. In all patients the operation was followed by primary intraoral wound healing without any signs of an early infection.

Ceftriaxone vs. azlocillin and netilmicin in the treatment of febrile neutropenic children.

Efficacy of the cephalosporin, ceftriaxone, was compared with that of the combination of the aminoglycoside, netilmicin, and the penicillin, azlocillin, in the treatment of febrile episodes in immunocompromised neutropenic children undergoing chemotherapy for neoplastic disease. During 100 separate febrile episodes, 40 strains of bacteria were isolated from the blood of 34 patients and a further 55 strains from other sites. Nine strains (four of which were staphylococci) to both netilmicin and azlocillin. There was no difference in clinical response between the two therapeutic regimens as assessed 4 and 7 days after treatment began. Ceftriaxone had the considerable practical advantages of once daily dosage without a need for blood monitoring. Ceftriaxone would appear to be effective as initial monotherapy in the treatment of bacterial infections in severely neutropenic children.

Gram-positive bacteraemia in granulocytopenic cancer patients.

In the four EORTC International Antimicrobial Therapy Cooperative Group trials, the frequency of gram-positive isolates has increased significantly from 29% of single-organism bacteraemias in trial I (1973-1976) to 41% in trial IV (1983-1985). In trial IV febrile and neutropenic (less than 1000 polymorphonuclear lymphocytes per microliter) cancer patients were randomized prospectively to receive either azlocillin plus a long course (at least 9 days) of amikacin, or ceftazidime plus a short course (3 days) of amikacin, or ceftazidime plus a long course of amikacin. Without modification of the allocated antibiotics, the overall response rates for gram-positive bacteraemias were similar for all three regimens (19/37 [51%], 8/23 [35%] and 14/30 [47%]), respectively. However, in patients with prolonged and severe neutropenia, treatment with azlocillin plus amikacin was significantly more effective than with ceftazidime plus 3 days' amikacin (7/10 vs. 0/7). The overall response rate for these infections was significantly lower than that observed in trial I (46% vs. 74%), but this was not associated with increased mortality. The response to treatment was significantly influenced by the susceptibility of the infecting strain to the beta-lactam. Multivariate analysis revealed that increasing age, presence of a central venous catheter and resistance to beta-lactam adversely affected outcome. Future studies should be designed to improve the outcome of gram-positive bacteraemia in neutropenic patients with cancer.

A randomised trial of empirical antibiotic therapy in febrile neutropenic patients with hematological disorders: ceftazidime versus azlocillin plus amikacin.

One hundred and two patients with neutropenia (less than 1 x 10(9)/L) secondary to primary hematological disorders or chemotherapy for hematological malignancies were prospectively randomised, upon the development of fever or other signs of infection, to receive empirical antibiotic treatment with either ceftazidime (+/- flucloxacillin) (n = 52) or azlocillin plus amikacin (+/- flucloxacillin) (A&A, n = 50). The two groups were equivalent with respect to clinical and laboratory parameters prior to antibiotic therapy and flucloxacillin was added to approximately 25% of the patients in each group on the clinical suspicion of Gram positive infection. When assessed at 96 hours, the complete response rates were 59.6% for the ceftazidime treated patients and 44% for A&A treated patients. Partial response rates were 17% and 20% respectively. This difference was not statistically significant. Eight patients died whilst on the trial, three of those initially randomised to ceftazidime and five initially randomised to A&A. Moderate to severe hypokalemia was encountered significantly less often in the ceftazidime treated group (p less than 0.01), whilst other parameters of toxicity were equivalent. No primary or acquired resistance to ceftazidime was encountered. Separate analysis of those patients who did not receive flucloxacillin yielded identical results. We conclude that ceftazidime (+/- flucloxacillin) is as efficacious as azlocillin plus amikacin (+/- flucloxacillin) in the empirical antibiotic management of such patients and is associated with a lower incidence of moderate to severe hypokalemia.

Comparative efficacy of ciprofloxacin, azlocillin, imipenem/cilastatin and tobramycin in a model of experimental septicemia due to Pseudomonas aeruginosa in neutropenic mice.

The in vivo activity of ciprofloxacin against Pseudomonas aeruginosa was studied in a septicemia model in neutropenic mice and compared to that of other antibiotics with established activity against P. aeruginosa. When given as a single agent, ciprofloxacin proved to be as effective as imipenem/cilastatin, whereas azlocillin and tobramycin were rather ineffective. After infection with higher challenge inocula, combinations of two (synergistic) antibiotics were more effective than single agent therapy in most instances. The combination of ciprofloxacin with azlocillin was at least as effective as that of imipenem/cilastatin with tobramycin. Selection of mutants with decreased sensitivity to ciprofloxacin occurred during therapy, however, post-therapy MICs of ciprofloxacin did not exceed a level of 1 mg/l and rises of MICs did not detrimentally influence treatment outcome. Taken together with the results of earlier studies, our data encourage the use of ciprofloxacin in gram-negative septicemia in neutropenic patients.

Treatment of pseudomonas aeruginosa colonisation in cystic fibrosis.

To test whether early treatment could postpone the chronic colonisation of the respiratory tract with mucoid strains of Pseudomonas aeruginosa in patients with cystic fibrosis, we performed a pilot study in 28 patients aged 2 to 18 years. A two week course of azlocillin (150 mg/kg/day) and tobramycin (10 to 15 mg/kg/day) was given after a mean duration of P aeruginosa colonisation of five months (range one to 11 months). Weight for height increased significantly by 3.5% (SEM 0.7%) of the predicted normal after chemotherapy. The eradication of P aeruginosa that was achieved in 18 children directly after hospital treatment was only temporary. Samples from only 10 and five patients remained negative three and six months after treatment, respectively. Five children remained free from P aeruginosa for a prolonged period of 14 to 32 months. We conclude that, apart from the clinical improvement in all patients, some children might benefit from early antipseudomonas treatment with respect to the bacteriological outcome. Most children, however, experience only a temporary reduction in colonisation. Further investigations in form of controlled clinical trials seem justified.