Metronidazole in prevention and treatment of bacteroides infections after appendicectomy.

The frequency of non-clostridial anaerobic infection was studied in 95 patients who had undergone acute appendicectomy: 49 received prophylactic metronidazole and 46 received placebo. Anaerobic infection did not develop in any of the metronidazole-treated patients, but infections did develop in nine (19%) of the 46 controls. Metronidazole is conveniently administered by suppository to patients who cannot take oral drugs. Five patients with intra-abdominal infections caused by non-clostridial anaerobes were successfully treated with metronidazole.     

Rectal administration of metronidazole in severely ill patients.

Ten severely ill patients with life threatening sepsis received metronidazole as suppositories and blood concentrations of the drug were measured twice daily over five days. Therapeutic blood concentrations of metronidazole were maintained at all times in all patients. Rectal administration of metronidazole is accepted as effective prophylaxis against infection associated with surgery and as treatment of established infection. This study shows that in gravely ill patients metronidazole administered as suppositories gives perfectly adequate therapeutic serum concentrations of the drug, but that to achieve these concentrations rapidly the first suppository should be given with an intravenous loading dose.     

The tropic effect of intrarectal deoxycholate on rat colorectum is unaffected by oral metronidazole

Intrarectal administration of sodium deoxycholate (SDC) enhances experimental colorectal carcinogenesis, an effect that is partly vitiated by oral metronidazole. The effect of topical SDC with or without concurrent metronidazole on colorectal cell proliferation was explored in male Sprague-Dawley rats (n = 30) allocated to five groups. Two groups received thrice weekly intrarectal instillations of 1 ml N saline or 1 ml 0.12 M SDC. A third group received SDC plus metronidazole 22.5 mg/kg/day in the drinking water. Controls had no instillations or metronidazole alone. At time of killing (10 weeks), crypt cell production rate (CCPR) was determined by the stathmokinetic technique for four large-bowel segments. Saline had no significant effect on colorectal CCPR but SDC produced increases throughout, varying from 53% in the proximal colon to 222% in the rectum (P less than 0.01). Metronidazole did not reduce this effect, although given alone it reduced colonic CCPR by 40 to 50%. The direct tropic effect of bile acids could largely explain their cocarcinogenic properties. Since metronidazole does not prevent this increase in cell proliferation, its mildly protective role against cancer may reflect the presence of fewer anaerobes capable of degrading bile acids to carcinogenic metabolites.     

The Tropic Effect of Intrarectal Deoxycholate On Rat Colorectum Is Unaffected By Oral Metronidazole

Abstract. Intrarectal administration of sodium deoxycholate (SDC) enhances experimental colorectal carcinogenesis, an effect that is partly vitiated by oral metronidazole. the effect of topical SDC with or without concurrent metronidazole on colorectal cell proliferation was explored in male Sprague-Dawley rats ( n = 30) allocated to five groups. Two groups received thrice weekly intrarectal instillations of 1 ml N saline or 1 ml 0.12 m SDC. A third group received SDC plus metronidazole 22.5 mg/kg/day in the drinking water. Controls had no instillations or metronidazole alone. At time of killing (10 weeks), crypt cell production rate (CCPR) was determined by the stathmokinetic technique for four large-bowel segments. Saline had no significant effect on colorectal CCPR but SDC produced increases throughout, varying from 53% in the proximal colon to 222% in the rectum ( P < 0.01). Metronidazole did not reduce this effect, although given alone it reduced colonic CCPR by 40 to 50%. the direct tropic effect of bile acids could largely explain their cocarcinogenic properties. Since metronidazole does not prevent this increase in cell proliferation, its mildly protective role against cancer may reflect the presence of fewer anaerobes capable of degrading bile acids to carcinogenic metabolites.     

Metronidazole activation and isolation of Clostridium acetobutylicum electron transport genes

An Escherichia coli F19 recA, nitrate reductase-deficient mutant was constructed by transposon mutagenesis and shown to be resistant to metronidazole. This mutant was a most suitable host for the isolation of Clostridium acetobutylicum genes on recombinant plasmids, which activated metronidazole and rendered the E. coli F19 strain sensitive to metronidazole. Twenty-five E. coli F19 clones containing different recombinant plasmids were isolated and classified into five groups on the basis of their sensitivity to metronidazole. The clones were tested for nitrate reductase, pyruvate-ferredoxin oxidoreductase, and hydrogenase activities. DNA hybridization and restriction endonuclease mapping revealed that four of the C. acetobutylicum insert DNA fragments on recombinant plasmids were linked in an 11.1-kb chromosomal fragment. DNA sequencing and amino acid homology studies indicated that this DNA fragment contained a flavodoxin gene which encoded a protein of 160 amino acids that activated metronidazole and made the E. coli F19 mutant very sensitive to metronidazole. The flavodoxin and hydrogenase genes which are involved in electron transfer systems were linked on the 11.1-kb DNA fragment from C. acetobutylicum.     

Single dose cefotaxime plus metronidazole versus three dose cefuroxime plus metronidazole as prophylaxis against wound infection in colorectal surgery: multicentre prospective randomised study.

OBJECTIVE--To establish whether a single preoperative dose of cefotaxime plus metronidazole was as effective as a standard three dose regimen of cefuroxime plus metronidazole in preventing wound infection after colorectal surgery. DESIGN--Prospective randomised allocation to one of two prophylactic antibiotic regimens in a parallel group trial. Group sequential analyses of each 250 patients were performed. SETTING--14 District general and teaching hospitals. PATIENTS--1018 Adults having colorectal operations were randomised, of whom 943 were evaluated. Demographic features, conditions requiring surgery, and operative procedures were similar in the two groups. Most patients had surgery for carcinoma of the colon or rectum. INTERVENTIONS--Group 1 received cefotaxime 1 g intravenously plus metronidazole 500 mg intravenously preoperatively. Group 2 received cefuroxime 1.5 g intravenously plus metronidazole 500 mg intravenously preoperatively, followed by cefuroxime 750 mg intravenously plus metronidazole 500 mg intravenously eight hours and 16 hours postoperatively. MAIN OUTCOME MEASURES--Development of surgical wound infection (as evidenced by the presence of pus), death, or discharge from hospital. RESULTS--Wound condition was scored on a five point scale on alternate days until discharge or for up to 20 days postoperatively. Wound infection rates were: group 1, 32/453 (7.1%; 95% confidence interval 4.7% to 9.4%); group 2, 33/454 (7.3%; 95% confidence interval 4.9% to 9.6%). Death rates (group 1: 26/470 (5.5%); group 2: 31/471 (6.6%], the incidence of postoperative complications, the median duration of hospital stay (12 days), and antibiotic tolerance were all similar in the two groups. Pooled data from groups 1 and 2 showed that wound infections were more frequent when minor faecal contamination had occurred at operation and when the duration of operation exceeded 90 minutes (greater than 90 min 11.2% of cases; less than 90 min 4.8%) and were associated with an extended hospital stay. CONCLUSIONS--A single preoperative dose of cefotaxime plus metronidazole is an efficacious as a three dose regimen of cefuroxime plus metronidazole in preventing wound infection after colorectal surgery and has practical advantages in eliminating the need for postoperative antibiotics.     

In Vitro Induced Anaerobic Resistance to Metronidazole In Trichomonas Vaginalis

ABSTRACT. Resitance to metronidazole detectable under anaerobic conditions was induced in two Trichomonas vaginalis strains (TV 10-02 and MRP-2) by cultivation at gradually increasing pressure of the drug (1-100 μ/ml) for 12 to 21 months. the resistant derivatives reproduced in anaerobic trypticase-yeast-extract-maltose medium at 100 μ/ml metronidazole and showed very high values of minimal lethal concentration for metronidazole in anaerobic in vitro assays (556-1,600 μ/ml at 48-h exposure to the drug). Stepwise selection was necessary to develop the resistance in either strain. Attempts to induce resistance by prolonged maintenance of trichomonads with constant, low or moderate drug concentrations (3-10 μ/ml) were unsuccessful. Freshly developed resistance to high concentrations of metronidazole was unstable in absence of drug pressure as well as after cryopreservation. Development of stable resistance required further cultivation at 100 μ/ml metronidazole. Unstable substrains did not revert to original susceptibility. They retained a moderate level of resistance, being able to grow at 10 μ/ml metronidazole. the strains with fully developed resistance had no activity of the hydrogenosomal enzymes pyruvate: ferredoxin oxidoreductase and hydrogenase and ceased uptake of [¹⁴C]-metronidazole. These findings indicate that the pyruvate oxidizing pathway responsible for metronidazole activation was inactivated and metabolism of the drug stopped.     

Amebiasis in HIV-1-infected Japanese men: clinical features and response to therapy

Invasive amebic diseases caused by Entamoeba histolytica are increasing among men who have sex with men and co-infection of ameba and HIV-1 is an emerging problem in developed East Asian countries. To characterize the clinical and epidemiological features of invasive amebiasis in HIV-1 patients, the medical records of 170 co-infected cases were analyzed retrospectively, and E. histolytica genotype was assayed in 14 cases. In this series of HIV-1-infected patients, clinical presentation of invasive amebiasis was similar to that described in the normal host. High fever, leukocytosis and high CRP were associated with extraluminal amebic diseases. Two cases died from amebic colitis (resulting in intestinal perforation in one and gastrointestinal bleeding in one), and three cases died from causes unrelated to amebiasis. Treatment with metronidazole or tinidazole was successful in the other 165 cases. Luminal treatment was provided to 83 patients following metronidazole or tinidazole treatment. However, amebiasis recurred in 6 of these, a frequency similar to that seen in patients who did not receive luminal treatment. Recurrence was more frequent in HCV-antibody positive individuals and those who acquired syphilis during the follow-up period. Various genotypes of E. histolytica were identified in 14 patients but there was no correlation between genotype and clinical features. The outcome of metronidazole and tinidazole treatment of uncomplicated amebiasis was excellent even in HIV-1-infected individuals. Luminal treatment following metronidazole or tinidazole treatment does not reduce recurrence of amebiasis in high risk populations probably due to amebic re-infection.     

TRICHOMONIASIS—Clinical Trial of Metronidazole (Flagyl?)

Metronidazole was given in various dosage regimens to 97 patients having microscopically diagnosed trichomoniasis.At the first examination after treatment all 97, including 76 to whom metronidazole had been given orally only, were found by culture and wet smear to be free of trichomonads.Reexamination of the 65 patients followed up for periods ranging from two weeks to 14 months revealed reappearance of trichomonads in eight cases.Nineteen husbands were treated. No patient had a recurrence after treatment of the husband.No effect of metronidazole on pregnancy or on fetal development was seen. Side effects, noted in 19 cases (20 per cent), generally were mild and transient and in no case were severe enough to terminate therapy before cure was effected.     

Clinical and microbiological efficacy of metronidazole and ornidazole in the treatment of urogenital trichomoniasis in men]

The aim of the study was to compare the efficacy of metronidazole and ornidazole in the treatment of urogenital trichomoniasis in men. The drugs were used randomly in usual doses as monotherapy: 210 patients, metronidazole and 217 patients, ornidazole. The clinical efficacy of metronidazole and ornidazole was stated in 57.6 and 94.5% of the patients and the microbiological efficacy was stated in 77.1 and 98.2% of the patients respectively. The side effects were recorded in 59.0 and 3.7% of the patients respectively. Thus, ornidazole proved to be a more efficient and safe agent vs. metronidazole in the treatment of urogenital trichomoniasis.     

Six regimens for the eradication of Helicobacter pylori (Hp) in duodenal ulcer patients: three consecutive trials (1995-1999).

AIM: to present our experience in eradicating Hp in three consecutive trials performed between 1995 and 1999. METHODS: 320 duodenal ulcer outpatients have been enrolled in three open, prospective controlled trials. Hp infection was confirmed by Giemsa stain and Rut. In Trial I, 52 cases received 20 mg omeprazole + 2 x 250 mg clarithromycin + 2 x 500 mg tinidazole (OCT), 48 patients were given 20 mg omeprazole, 2 x 1000 mg amoxicillin + 2 x 500 mg metronidazole (OAM) for 7 days; in Trial II, 48 cases received 40 mg pantoprazole + 2 x 1000 mg amoxicillin + 2 x 500 mg clarithromycin (PAC) for 7 days and 5l cases 2 x 400 mg ranitidin bismuth citrate + 2 x 500 mg clarithromycin for 14 days (RBC-C); in Trial III, 60 cases were treated with 2 x 30 mg lansoprazole + 2 x 250 mg clarithromycin + 2 x 500 mg metronidazole and 6l patients received 2 x 400 mg ranitidin bismuth citrate+2 x 250 mg clarithromycin + 2 x 500 mg metronidazole (RBC-CM). The patients were controlled within 4-6 weeks by endoscopy in trials I-II and 13C-urea breath test in trial III. RESULTS: Eradication rates on ITT/PP basis were: OCT: 72.3/80.2% vs OAM 51.2/63.5% (P = 0.02/P = 0.03); PAC: 80.8/88.3% vs RBC-C 80.3/85.4% (P = 0.65/0.67) and LCM 78.3/92.1% vs RBC-CM 78.7/90.5% (P = 0.86/P = 0.93). Side effects occurred in 5.2, 8.6, 9.5, 14.5, 13.5 and 18.3% of the cases. CONCLUSION: Regimens using 2 x l PPI or RBC + 2 antibiotics for l week proved to be the most effective for Hp eradication in duodenal ulcer patients.     

Nifuratel Compared with Metronidazole in the Treatment of Trichomonal Vaginitis

Nifuratel (Magmilor) was compared with metronidazole (Flagyl) in the treatment of trichomonal vaginitis by a randomized double-blind trial. Only 18 out of 47 patients (38%) treated with nifuratel were found to be cured, whereas 42 out of 49 patients (85%) treated with metronidazole were cured. Severe reactions, necessitating withdrawal of treatment, occurred in three patients treated with nifuratel. There were no serious side-effects with metronidazole. The results of this trial indicate that nifuratel is not a satisfactory substitute for metronidazole in the treatment of trichomoniasis.     

Clinical features and laboratory findings of human parvovirus B19 in human immunodeficiency virus-infected patients

Immunocompromised patients may develop severe chronic anaemia when infected by human parvovirus B19 (B19V). However, this is not the case in human immunodeficiency virus (HIV)-infected patients with good adherence to highly active antiretroviral treatment (HAART). In this study, we investigated the clinical evolution of five HIV-infected patients receiving HAART who had B19V infections confirmed by serum polymerase chain reaction. Four of the patients were infected with genotype 1a strains and the remaining patient was infected with a genotype 3b strain. Anaemia was detected in three of the patients, but all patients recovered without requiring immunoglobulin and/or blood transfusions. In all cases, the attending physicians did not suspect the B19V infections. There was no apparent relationship between the infecting genotype and the clinical course. In the HAART era, B19V infections in HIV-positive patients may be limited, subtle or unapparent.     

Mechanism of metronidazole-resistance by isolates of nitroreductase-producing Enterococcus gallinarum and Enterococcus casseliflavus from the human intestinal tract

Enterococcus casseliflavus and Enterococcus gallinarum strains resistant to metronidazole, nitrofurantoin and nitrofurazone were isolated from fecal samples of a patient with recurrent ulcerative colitis treated with metronidazole. Unlike other metronidazole-resistant bacteria, these strains produced nitroreductase but metabolized metronidazole to compounds that could not be detected by liquid chromatography with UV or mass spectral analysis. Metronidazole-susceptible Clostridium perfringens grew equally well in spent cultures of Enterococcus spp. incubated with or without metronidazole. These data indicate that the nitroreductases produced by these Enterococcus strains did not activate metronidazole to bactericidal metabolites and these bacteria may reduce the effectiveness of metronidazole. We have indirect evidence for an alternative pathway that results in metronidazole resistance. These strains of enterococcus had nitroreductase so resistance should not have occurred.     

Subjective adverse reactions to metronidazole in patients with amebiasis

Subjective adverse reactions to metronidazole were analyzed in 111 patients with amebiasis. Metronidazole was administered to 36 patients at a daily dose of 2250 mg and 75 patients at daily doses lower than 2250 mg. The reactions reported included nausea without vomiting in 11 (9.9%) patients, nausea with vomiting in 2 (1.8%), dysgeusia in 2 (1.8%), diarrhea in 1 (0.9%), headache in 1 (0.9%), numbness in 1 (0.9%), dizziness in 1 (0.9%), urticaria in 1 (0.9%), exanthema in 1 (0.9%), and discomfort in 1 (0.9%). Nausea was reported by 28% (10/36) of the patients receiving metronidazole at a daily dose of 2250 mg and 4% (3/75) of the patients receiving lower daily doses. The duration of the metronidazole administration in days was not associated with the appearance of nausea. No life-threatening adverse reactions were identified, and good clinical therapeutic effects were observed in 96% (107/111) of the patients. While metronidazole appears to be a safe anti-protozoal agent for patients with amebiasis, our results indicate that a daily metronidazole dose of 2250 mg is excessive for amebiasis, as it often induces nausea.     

Study of different off-line sample processing procedures and the measurement of antibiotic and antiviral levels in human serum by high-performance liquid chromatography

We attempted to devise a preparation method for clinical samples that could be used for all antibiotics and antivirals. We studied thirteen antibiotics, including five penicillins, four cephalosporins, metronidazole, ofloxacin, and sulfamethoxazole and four protease inhibitors including indinavir, retonavir, nelfinavir, and sequinavir. We compared four sample preparation techniques including solvent precipitation, filtration and resin column. We employ HPLC methods based on a minimal number of columns and mobile phases. We were unable to find one sample preparation method that could be used for all antibiotics and antivirals. But, we did develop an algorithm for determining optimal processing procedures for all drugs.     

Metronidazole Susceptibility in Clostridium difficile Isolates Recovered from Cases of C. difficile -associated Disease Treatment Failures and Successes

Despite high clinical efficacy, a small number of patients with Clostridium difficile -associated disease (CDAD) do not respond to treatment with metronidazole. We looked for evidence of metronidazole resistance in human C. difficile isolates from 632 patients with CDAD treated with metronidazole, 14(2%) of whom failed treatment. C. difficile isolates were available from 10 of the metronidazole-failure cases and were matched with isolates from 20 contemporary control CDAD patients who responded to treatment with metronidazole. The mean (±SD) MIC of metronidazole-failure-associated C. difficile isolates was similar to the mean (±SD) MIC of isolates from metronidazole-success cases (E-test; 0.23±0.21 vs 0.29±0.19μg/mL, P=0.4). Restriction endonuclease analysis typing revealed that no particular C. difficile strain was associated with metronidazole treatment failure. Clinical CDAD treatment failures with metronidazole could not be attributed to decreased susceptibility of the causativeC. difficle isolate to metronidazole.     

Nitrimidazine Compared with Metronidazole in the Treatment of Vaginal Trichomoniasis

A new substituted nitroimidazole, nitrimidazine (Naxogin), is compared with the established drug, metronidazole (Flagyl), for the treatment of vaginal trichomoniasis in a randomized double-blind trial. Nitrimidazine cured 39 (68%) out of 57 patients and showed no undesirable effects other than nausea in one patient. Metronidazole cured 51 (89%) out of 57 patients and also caused nausea in one patient; this cure rate corresponds with that previously reported in other trials. In the recommended dosage nitrimidazine is inferior to metronidazole, but is sufficiently effective to be useful in cases of intolerance to metronidazole.     

乳酸杆菌活菌制剂用于治疗老年性阴道炎合并细菌性阴道病临床探讨

目的探讨乳酸杆菌活菌制剂用于治疗老年性阴道炎合并细菌性阴道病的临床疗效。方法对118例老年性阴道炎合并细菌性阴道病患者随机分3组,分别予以乳酸杆菌活菌制剂局部用药和（或）口服甲硝唑,进行疗效比较。结果乳酸杆菌活菌制剂和甲硝唑联合应用对治疗老年性阴道炎合并细菌性阴道病疗效显著高于单一用药的疗效,组间差异具有显著性（P〈0.05）;复发率低于单一用药。结论乳酸杆菌活菌制剂与甲硝唑联合治疗老年性阴道炎合并细菌性阴道病有比较好的治疗效果,不易复发。