Enteropathogenic E. coli gastroenterocolitis in neonates treated with fosfomycin

The effect of calcium salt of fosfomycin in the treatment of 43 neonates suffering from acute gastroenterocolitis produced by enteropathogenic E. coli is evaluated. The minimal inhibitory concentration of these E. coli was, generally, lower than 128 mug/ml. Dosages of 150-200 mg/kg body weight/day were administered orally every 8 h. This treatment lasted for 4 days only. Clinical evolution was favorable in 38 (88%) babies and bacteriological evolution in 30 (70%). In eight cases a different flora to the initial was selected during the treatment with fosfomycin. None of the cases treated showed any toxic alteration attributed to the antibiotic.

Fosfomycin treatment of Haemophilus influenzae infection in mice

Haemophilus influenzae is an important pathogen in respiratory infections in children and often is implicated in otitis media. It is sensitive in vitro to a number of antibiotics, some of which are used clinically for the treatment of such infections. We have checked the in vitro sensitivity of a type b strain of H. influenzae. When tested in Levinthal's broth prepared with laked rabbit blood, the culture was most sensitive to tetracycline, ampicillin and penicillin and was somewhat less sensitive to cephalothin, fosfomycin, cephaloridine, and chloramphenicol. However, when this same strain was used to infect mice, fosfomycin was more active than ampicillin, tetracycline, chloramphenicol, penicillin or the cephalosporins.

Treatment of respiratory infections with fosfomycin

Results are presented for a series of 29 patients, 14 males and 15 females, with serious respiratory infections, in which fosfomycin proved effective. In all cases the study was completed by bacteriological, clinical, radiological and analytical controls. The average dose was 6 g/day (3 g orally and 3 g intramuscularly) for 1 or 2 weeks. The four isolated were P. aeruginosa, E. coli, Klebsiella-Enterobacter and D. pneumoniae. Overall sensitivity percentages were best for fosfomycin, gentamicin and colistin. Of the 29 germs isolated, only one strain of P. aeruginosa became resistant: this represents 3% resistance development. No side effects of intolerance or signs of hepatorenal insufficiency were observed during the treatment. Of the 29 patients treated, 22 were clinically cured, denoting 76% success.

The passage of fosfomycin into the cerebrospinal fluid in children's meningitis

This report deals with the results of a study that was made on the passage of fosfomycin into the CSF in 22 children with meningitis (11 parotideal meningitis and 11 meningococcal meningitis). The plasma and liquor levels of fosfomycin were determined in the acute phase of the illness and after the normalization of the CSF, with the object of studying the passage of the antibiotic through the blood-brain barrier in the presence and absence of meningeal inflammation. A greater permeability of the meninges was found to exist when they were in an inflammatory state and there seems to be a certain accumulative effect in the CSF when the fosfomycin is administered by intravenous perfusion. The concentrations that were obtained in the CSF were not high enough to justify the exclusive use of fosfomycin in the treatment of meningitis. Nevertheless, considering its wide antibacterial spectrum, its MIC against different microbial species and its lack of toxicity, we believe that fosfomycin can be of use when associated with other antibiotics in the treatment of meningitis caused by S. aureus, D. pneumoniae, H. influenzae, E. coli, P. mirabilis and S. marcescens.

Treatment of typhoid fever with fosfomycin alone and associated to chloramphenicol or ampicillin

Treatment with fosfomycin alone and associated to subtherapeutic doses of chloramphenicol or of ampicillin, has been tried on 50 patients with typhoid fever and on four carriers of S. typhi in the Hospital del Rey. 15 patients were treated with fosfomycin alone, 22 with fosfomycin plus chloramphenicol and 13 with fosfomycin plus ampicillin. The treatment lasted 15-20 days. The results have been evaluated clinically and bacteriologically, haemo- and coprocultures being carried out. The sensitivity of the isolated germs has been studied, including MIC and the synergism in vitro between fosfomycin-chloramphenicol and fosfomycin-ampicillin. Fosfomycin, chloramphenicol and ampicillin determinations have been carried out on the blood. The cures obtained were 67, 82 and 92% respectively with fosfomycin, fosfomycin-chloramphenicol and fosfomycin-ampicillin. We believe that this antibiotic can be useful in the treatment of typhoid fever, associating it to chloramphenicol or ampicillin, due to the synergism existing between them and given the results we have obtained.

A study of the levels of fosfomycin in the cerebrospinal fluid in adult meningitis

In order to determine the liquor concentration of fosfomycin, we chose 27 patients who were suffering from meningitis with different etiology. According to route, type of administration and doses employed, we classified the patients into five groups. Blood samples were taken from the patients 1 h after concluding the administration of the antibiotic and 2 h after the CSF sample. The concentration of fosfomycin in the serum and the CSF were then determined in the laboratory. In order to evaluate the results we divided our cases into three groups according to the state of their meningeal inflammation. In the first group of patients with active meningitis, we obtained an average concentration of fosfomycin in the serum of 65.20 mug/ml and in the CSF of 10.88 mug/ml. In the second group of patients with meningitis in the remission stage, the concentration of fosfomycin in the serum was 83.58 mug/ml and in the CSF it was 9.63 mug/ml. In the third group of patients with their meningitis cured, the concentration of fosfomycin in the serum was 66.45 mug/ml and in the CSF it was 4.95 mug/ml. On the basis of the concentrations obtained and with regard to the sensitivity in vitro, we concluded that fosfomycin can be useful in the treatment of meningitis caused by Pneumococcus, Staphylococcus, E. coli and other gram-negative bacilli.

Fosfomycin in the treatment of bacterial infections: summary of clinical trials in Japan

The Japan Research Committee of Fosfomycin was organized in the fall of 1972 to promote the basic and clinical studies on fosfomycin. First of all, a subcommittee of fosfomycin consisting of a limited number of members was organized to establish the methods of determination on its antibacterial activity and its concentration in the biological fluid, and the most applicable methods were devised. The clinical trials on its oral form in a small scale were commenced from spring in 1973, and then gradually expanded to almost all of Japan. The clinical trials on its parenteral intravenous form were also undertaken from the latter half of 1973. The basic and clinical results obtained from hospitals and institutes almost all over Japan, to which members of the above Committee belong, were presented by speakers under a hot discussion in two symposia which were held by the Japan Society of Chemotherapy; one on its oral form in June 1974, and another on its parenteral form in December 1974. I served as chairman in both of the symposia. The clinical results of fosfomycin in Japan which were mainly collected in both symposia are described below. Its antibacterial activity, and absorption and exretion will be presented elsewhere in this volume. Clinical results of its oral form: Dosage forms of fosfomycin-Ca salt, capsule and granules, were prepared for its clinical trials. It resulted effective in about 76% of 1,200 patients with infection due to gram-positive or gram-negative (Pseudomonas, Salmonella, Escherichia coli, etc.) bacteria in several fields. As far as rates of efficacy were concerned, it was more effective in surgical, urological, ophthalmic and some other fields than in internal and pediatric ones. Fosfomycin was given in a dose of 2-3 g/day for adults or 100-130 mg/kg for infants and children in most cases. Furthermore, it can be favorably mentioned that fosfomycin was proved to be effective in salmonellosis and resistant shigellosis by a certain research group specialized in the therapy of infectious enteritis. Clinical results of its parenteral form: Sterlized bulk material of fosfomycin-Na salt was prepared in a vial for clinical use. Similarly as in the case of oral form, it was applied to about 500 patients with several infections. It resulted effective in about 68% of them. This percentage was not as high because of the higher frequency of application to severe patients or patients with underlying disease. Fosfomycin was intravenously administered by one shot or drip infusion in a dose of 2-4 g/day for adults, or 100-250 mg/kg for infants and children in most cases. Adverse reactions: In oral form, the incidence of adverse reactions was about 10% but most of them were slight gastrointestinal disorders. In an extremely small number of patients a rise of SGOT and/or SGPT was observed. In parenteral form, the incidence of adverse reactions was a little higher, being about 17% including a rise of SGOT and/or SGPT, vascular pain, nausea, and vomiting, etc...

Activity of fosfomycin in the treatment of bacterial infections

30 patients with different infections were treated with fosfomycin: 13 had urinary infections, 14 had pneumonial infections, 2 had staphylococcus osteomyelitis and 1 had staphylococcus septicemia. The antibiotic was administered in doses ranging from 100 to 230 mg/kg/day, with periods of treatment that lasted from 5 to 58 days. The doses were administered every 6 h by the oral or intramuscular route. A total of 35 organisms were isolated: 7 E. coli, 7beta-hemolitic Streptococcus, 6 Proteus sp., 6 S. aureus, 6 S. viridans, 2 Klebsiella sp. and 1 negative coagulase S. aureus. All were sensitive to fosfomycin in vitro, as was revealed by the diffusion in discs method. The therapeutic results were good in 29 of the 30 cases (96.7%). There were no important side effects. A patient complained of a local pain in the area of the injection. The transaminases increased temporarily in 2 patients. One patient had a moderate eosinophilia while under treatment.

Evaluation of fosfomycin in an intensive care unit

Sensitivity to fosfomycin has been studied and recorded throughout a period of 12 months in the bacteriological isolations originating from this Intensive Care Unit. The 548 samples were biological products obtained from patients admitted to this unit (bronchial exudates, urine, wounds, blood, cava catheters and cerebrospinal fluid). The highest percentage of sensitivity was given by S. aureus coagulase (+), S. fecalis and E. coli (91, 89 and 84% respectively), and the least by P. aeruginosa and Providencia (33 and 8% respectively). A summary is included of 8 seriously ill patients admitted with varied septic processes, produced by germs sensitive to fosfomycin and treated with this, in 5 cases alone and in 3 cases with gentamicin and carbenicillin. Of those who were treated with fosfomycin alone: three were cured, one died on the sixth day through circulatory, respiratory and renal deficiences and the other with respiratory deficiency. Those treated with the combined antibiotics: two were cured and the other died of sepsis on the fourth day.

Fosfomycin in acute bronchopneumopathies

Fosfomycin has been tested in 25 adult patients with bronchial or bronchopulmonary acute processes, of which 13 were simple acute processes of a greater or lesser severity, and 12 acutenesses of chronic bronchial processes. The germs found most frequently in the sputum cultures were Streptococcus pneumoniae and Klebsiella. Fosfomycin was used intramuscularly with doses of 4 g/day, for an average of 10 days. The results obtained were 16 cures, 7 improvements and 2 failures, which represents 92% success with 8% failures.

Antibiotherapy of Serratia marcescens septicemia in children

The clinical and bacteriological response of 38 treatments performed on 24 children (11 of them neonates) carrying out separate treatments with carbenicillin (2 treatments), gentamicin [4], fosfomycin [6], and associated treatments with gentamicin plus carbenicillin [6], fosfomycin plus gentamicin [18] and fosfomycin plus carbenicillin [2] are considered. The clinical cure was obtained in 21 children (87.5%). The most effective treatment was fosfomycin plus gentamicin; both antibiotics showed synergism in vitro on isolated Serratia strains. A dosage of 75 mg/kg fosfomycin enables serum levels of about 32 mug/ml during 4-5 h, being this level higher to the MIC of all isolated strains of S. marcescens.

Fosfomycin in pneumococcal meningitis

A study has been made of 12 patients with pneumococcal meningitis with ages ranging from 12 months to 59 years. In all cases pneumococcus was isolated in the cerebrospinal fluid (CSF). Seventeen pneumococci were studied for their sensitivity to fosfomycin, ampicillin and gentamicin, including their MIC. All were sensitive to fosfomycin and ampicillin and 7 to gentamicin. On the other hand there has also been made a study of the interaction between fosfomycin plus ampicillin and fosfomycin plus gentamicin. The concentration of antibiotics in plasma and CSF had been determined. The association of fosfomycin to penicillin or ampicillin was also studied in some cases, depending on whether the patient was younger or older than 2 years, and in other cases, the association of fosfomycin with gentamicin. The concentrations of antibiotics in the CSF varied according to the stage of evolution of the meningitis. As regards clinical results, 10 cures and 2 failures have been obtained. The pneumococcus was eradicated from the CSF in all cases, including the two failures, in the control carried out 2-3 days after beginning of treatment, the rest of the analytical data of the CSF became normal within 5 and 17 days treatment.

Fosfomycin in chronic urinary infections

Fosfomycin has been used on 40 patients with serious urinary infections of different clinical nature, and produced by repetitive infection (prostatisms, carcinomas, lithiasis, hydronephrosis, etc.) The following were isolated in the urocultures: E. coli (60%), Klebsiella (15%), P. aeruginosa (15.0%), Proteus sp. (15.0%), Staphylococcus (5%), S. faecalis (2.5%) and Paracolobactrum coliforme (2.5%). All the germs isolated before treatment were sensitive to fosfomycin. The results, as regards response to the bacteriuria, were 71.4% eradication of the infection, 17.2% reinfections and 11.4% failures. The results are considered very satisfactory in view of the etiopathogenic nature of the processes under treatment.

Fosfomycin in patients subjected to periodic hemodialysis

The sensitivity to fosfomycin which is found in organisms that are frequently found in urinary infections and the lack of toxicity of this antibiotic were the reasons for which we tested fosfomycin on patients who were subjected to periodic hemodialysis. We were interested in studying (1) if fosfomycin was dialyzable, and (2) its therapeutic pattern in these patients. We selected a group of 27 patients from our programme of periodic hemodialysis who spend 18 h each week in three sessions with an RSP Travenol artificial kidney, using Ultra Flo II as the dialytic unit. They were all free of infection and had not received any antibiotics for 40 days before the test was carried out. They were administered 1 or 2 g of fosfomycin by the intravenous route at the time of beginning the dialysis. Blood samples and samples from the dialytic bath were taken before administering the fosfomycin, and 1/2, 3 and 6 hours after administering it. Our results show that fosfomycin is 70-80% dialyzed by the membranes of the artificial kidney and that during the hemodialysis, given the clearance which the dialyzing membrane makes of the antibiotic, the usual doses of fosfomycin should not be altered. No side effects were observed in any of the patients.

Fosfomycin in a traumatological department

Fosfomycin has been used in the treatment of 99 patients suffering from varying kinds of osseous processes and divided into 2 groups, one of 60 patients who were not operated on, and another of 39 who were operated. A treatment only with fosfomycin was tried initially by intravenous infusion (8-16 g/day during 2-4 days), then by the intramuscular route (2-8 g/day during 2-6 days) and finishing with treatment by the oral route (2-4 g/day during 2-6 days). The results have been excellent, all cases progressing with no septic complications. As for secondary effects, we have had only one case in which a rash appeared at the end of treatment. Intravenous infusion has been well tolerated with no sign of phlebitis in any patient.

Neurosurgical infection treated with fosfomycin and 6-methylprednisolone

A left parietal parasagittal meningioma was removed in a 67-year-old female patient. In the postoperative period she had a neurosurgical cerebral suppurating infection: subdural, epidural and epicranial, connected to the exterior by several fistulas. In the operative revision and after a culture, the germ causing the infection, E. coli, was isolated. Treatment was begun with 16 g of intravenous fosfomycin and 120 mg daily of 6-methylprednisolone intramuscularly, and this treatment cured the patient.

Blood and urinary concentrations of fosfomycin as a function of the renal function value

The following parameters were considered in studying 43 subjects under treatment for urinary infections with different degrees of renal insufficiency: the maximum blood concentrations, the plasmatic half-life, and the urinary concentrations of fosfomycin as a function of the plasma creatinine of the subject treated. The curve of the average maximum blood concentrations show a parabola-like increase, the plasmatic half-life followed the same tendency, while the curve of the average urinary concentrations presented an exponential decrease. The urinary concentrations were, nevertheless, always higher than 100 mug/ml regardless of the degree of renal insufficiency and even in the subjects who had a very high plasma creatinine. Given its absence of renal and systemic toxicity, the daily dosage of fosfomycin could remain unchanged regardless of the degree of insufficiency.