Comparative double-blind study of 200- and 400-mg enoxacin given orally in the treatment of acute uncomplicated urethral gonorrhea in males

The battle against emerging antibiotic resistance: should fluoroquinolones be used to treat children?

Inappropriate use of antibiotic drugs in humans and animals has led to widespread resistance among microbial pathogens. Resistance is the phenotypic expression corresponding to genetic changes caused by either mutation or acquisition of new genetic information. In some cases, multidrug resistance occurs. Streptococcus pneumoniae is one of the most important respiratory pathogens, playing a major role in both upper and lower respiratory tract infections. Pneumococcal resistance to antimicrobials may be acquired by means of horizontal transfer followed by homologous recombination of genetic material from the normal flora of the human oral cavity or by means of mutation. Resistance to penicillins and macrolides has been increasing for some time, but, recently, fluoroquinolone resistance has become an issue as well. We are concerned that, if fluoroquinolones are approved for use in children, their widespread use will result in rapid emergence of pneumococcal resistance, because children are more often colonized in the nasopharynx with high-density populations of pneumococci than are adults.

High prevalence of high-level ciprofloxacin resistance in Neisseria gonorrhoeae in Tel Aviv, Israel: correlation with response to therapy

A survey of the drug susceptibilities of gonococcal isolates from 100 consecutive patients attending clinics in the Tel Aviv area of Israel during the period from February to September 2000 has shown a 61% rate of ciprofloxacin resistance (MICs, > or =1 microg/ml); 51 isolates were highly resistant (MICs, > or =4 microg/ml). Ciprofloxacin-resistant strains were more prevalent among isolates with chromosomally mediated resistance to penicillin and tetracycline. Therapeutic failures with ciprofloxacin correlated with MICs of > or =1 mg/ml (P < 0.01). The high rate of ciprofloxacin resistance coinciding with a sharp rise in the incidence of gonorrhea precludes the use of fluoroquinolone drugs for the empirical treatment of gonococcal infections acquired in Israel.

Antimicrobial resistance of Neisseria gonorrhoeae and high prevalence of ciprofloxacin-resistant isolates in Japan, 1993 to 1998

To assess the antimicrobial resistance of Neisseria gonorrhoeae isolated from 1993 through 1998 in Japan, susceptibility testing was conducted on 502 isolates. Selected isolates were characterized by auxotype and analysis for mutations within the quinolone resistance-determining region (QRDR) in the gyrA and parC genes, which confer fluoroquinolone resistance on the organism. Plasmid-mediated penicillin resistance (penicillinase-producing N. gonorrhoeae) decreased significantly from 1993-1994 (7.9%) to 1997-1998 (2.0%). Chromosomally mediated penicillin resistance decreased from 1993-1994 (12.6%) to 1995-1996 (1.9%) and then increased in 1997-1998 (10.7%). Chromosomally mediated tetracycline resistance decreased from 1993-1994 (3.3%) to 1997-1998 (2.0%), and no plasmid-mediated high-level tetracycline resistance was found. Isolates with ciprofloxacin resistance (MIC >/= 1 microg/ml) increased significantly from 1993-1994 (6.6%) to 1997-1998 (24.4%). The proline-requiring isolates were less susceptible to ciprofloxacin than the prototrophic or arginine-requiring isolates. Ciprofloxacin-resistant isolates contained three or four amino acid substitutions within the QRDR in the GyrA and ParC proteins.

Antimicrobial resistance in Neisseria gonorrhoeae in Finland, 1976 to 1995. The Finnish Study Group For Antimicrobial Resistance

BACKGROUND AND OBJECTIVES

The worldwide increase in antimicrobial resistance in Neisseria gonorrhoeae prompted the authors to evaluate the status and course of resistance in gonococci in Finland.

GOALS

The minimal inhibitory concentrations (MIC) of penicillin, tetracycline, spectinomycin, ciprofloxacin, ceftriaxone, and cefixime were tested for 337 consecutive clinical N. gonorrhoeae isolates collected in 19 Finnish microbiology laboratories in 1993.

STUDY DESIGN

The results were compared with data obtained in three Finnish laboratories in 1986 and contrasted with the development of the incidence of gonorrhea and the prevalence of penicillinase-producing N. gonorrhoeae (PPNG) in Finland, 1976 to 1995. The number of strains with an elevated MIC to ciprofloxacin was assessed by questionnaire.

RESULTS

A decrease, from more than 50% in 1986 to 20% in 1993, of strains susceptible to penicillin and tetracycline was observed. The prevalence of PPNG increased from 0% (1976) to 5.7% (1995). In 1995, two strains with a ciprofloxacin MIC of > or = 32 micrograms/ml were reported. No resistance to ceftriaxone or spectinomycin was detected.

CONCLUSIONS

In spite of the rarity of gonorrhea and the availability of efficient antimicrobials in Finland, monitoring of the antimicrobial resistance of N. gonorrhoeae remains important.

Antimicrobial activity of trovafloxacin tested against ciprofloxacin-susceptible and -resistant Neisseria gonorrhoeae. Interpretive criteria and comparisons with Etest results

Trovafloxacin, a new fluorinated naphthyridine, has enhanced activity against Gram-positive cocci, while retaining an excellent spectrum against Gram-negative pathogens. It has been used successfully in clinical trials for therapy of gonorrhea, and this investigation proposes in vitro susceptibility testing criteria for trovafloxacin. A total of 150 Neisseria gonorrhoeae clinical isolates (50 resistant to ciprofloxacin; MICs > or = 0.12 microgram/mL) were tested by methods recommended by the National Committee for Clinical Laboratory Standards (NCCLS) and the Etest (AB BIODISK, Solna, Sweden). Trovafloxacin was very active against gonococci (MIC90, 0.008 to 0.015 microgram/mL), but was generally eightfold less potent versus ciprofloxacin-resistant strains. Etest results correlated well (r = 0.96; 98% of MICs +/- one log2 dilution) compared to the reference agar dilution test. Reference agar dilution and Etest MICs were compared to disk-diffusion test zones (10-micrograms trovafloxacin disk), and excellent categorical agreement (89.4 to 99.3%) was achieved without significant false-susceptible or -resistant error (< or = 1.3%). Tentative breakpoints were suggested initially to outline the ciprofloxacin-susceptible and trovafloxacin-susceptible as susceptible (MIC, < or = 0.015 microgram/mL; zones > or = 47 mm), and strains with various well-characterized mutations of the gyr A and par C genes as either intermediate or resistant to trovafloxacin. When the results of clinical studies treating ciprofloxacin-resistant N. gonorrhoeae with trovafloxacin become available, the alternative breakpoints could be utilized for resistant MIC breakpoints of > or = 0.06 microgram/mL or > or = 0.5 microgram/mL. Trovafloxacin was stable in supplemented GC agar for 21 days stored at refrigerated temperatures. These in vitro results indicate that trovafloxacin should be a very acceptable agent for therapy of gonorrhea and other common sexually transmitted pathogens.

Enoxacin: a reappraisal of its clinical efficacy in the treatment of genitourinary tract infections

Enoxacin is a 6-fluoronaphthyridinone antibacterial agent with good in vitro activity against Neisseria gonorrhoeae and most Gram-negative urinary tract pathogens. It is less active in vitro against Acinetobacter spp., Pseudomonas aeruginosa, and most Gram-positive bacteria, than against Gram-negative organisms. Enoxacin is rapidly absorbed, with a high oral bioavailability (87 to 91%). Of the absorbed dose, 44 to 56% is excreted unchanged in the urine, with peak urinary concentrations (>500 mg/L within 4 hours) remaining high (>100 mg/L) for up to 24 hours, sufficient to inhibit most urinary tract pathogens. Single (400 mg) and multiple oral dose regimens (100 to 600 mg twice or 3 times daily for 5 to 14 days) of enoxacin are as effective for the treatment of patients with complicated or uncomplicated urinary tract infections as other antibacterial agents such as amoxicillin, cefuroxime axetil, cotrimoxazole (trimethoprim-sulfamethoxazole) or trimethoprim. Noncomparative data suggest that enoxacin is also an effective agent for the treatment of prostatitis. Single 400 mgoral doses of enoxacin produce >/- 95% bacteriological cure rates in gonococcal infections, comparable to those produced by single intramuscular doses of ceftriaxone 250 mg. Perioperative doses of oral enoxacin 200 mg provide effective prophylaxis against postoperative bacteriuria after transurethral resection of the prostate. Concomitant administration of enoxacin with a number of commonly used therapeutic agents (e.g. antacids, methylxanthines, warfarin) affects the pharmacokinetic properties of either enoxacin or the coadministered agents. Enoxacin is reasonably well tolerated, with the incidence of adverse experiences ranging from 0 to 24%. Adverse events are mainly gastrointestinal, neurological or dermatological and resolve with minimal intervention. Overall, although enoxacin exhibits a number of clinical characteristics that are similar to those of other agents for the treatment of genitourinary tract infections, the advantages offered by this agent generally do not outweigh those of alternative fluoroquinolone agents. Thus, it is likely to prove to be yet another addition to the list of agents available for the management of these infections.

Proposed criteria for interpretation of susceptibilities of strains of Neisseria gonorrhoeae to ciprofloxacin, ofloxacin, enoxacin, lomefloxacin, and norfloxacin

The susceptibilities of 45 strains of Neisseria gonorrhoeae, including 25 strains susceptible to ciprofloxacin (MICs, < or = 0.06 microgram/ml) and 20 strains exhibiting decreased susceptibilities to ciprofloxacin (MICs, > or = 0.125 microgram/ml), to ciprofloxacin, ofloxacin, enoxacin, lomefloxacin, norfloxacin, and nalidixic acid were determined by agar dilution and disk diffusion. On the basis of theoretical calculations of predicted susceptibilities at which infections may fail therapy (supported by observed failures of infections to respond to the therapeutic doses of enoxacin and ciprofloxacin), the Centers for Disease Control and Prevention has adopted the following agar dilution breakpoints for interpretation of resistance to these agents: MICs of > or = 1.0 microgram of ciprofloxacin, enoxacin, and norfloxacin per ml and MICs of > or = 2.0 micrograms of ofloxacin and lomefloxacin per ml. The corresponding disk diffusion breakpoints for these agents were as follows: ciprofloxacin, < or = 29 mm; ofloxacin, < or = 24 mm; enoxacin, < or = 31 mm; lomefloxacin, < or = 26 mm; and norfloxacin, < or = 32 mm. The Centers for Disease Control and Prevention recommends two strains as interim quality control strains for susceptibility testing of ciprofloxacin and ofloxacin. These are N. gonorrhoeae CDC-10,328 (MIC of ciprofloxacin, 0.125 to 0.25 microgram/ml [inhibition zone diameter range, 30 to 34 mm]; MIC of ofloxacin, 0.5 microgram/ml [inhibition zone diameter range, 27 to 32 mm]) and N. gonorrhoeae CDC-10,329 (MIC of ciprofloxacin, 1.0 to 2.0 micrograms/ml [zone inhibition diameter range, 21 to 26 mm]; MIC of ofloxacin 2.0 micrograms/ml [inhibition zone diameter range, 18 to 21 mm]).

Quinolones

Fluoroquinolones represent a major advance in antimicrobial chemotherapy. Currently, there are five fluoroquinolones approved by the FDA, and many more quinolones are expected to become available in years to come. Although their clinical utility is constantly expanding, they have been best studied in complicated urinary tract infections, chronic osteomyelitis caused by gram-negative bacilli, bacterial gastrointestinal infections such as traveler's diarrhea and typhoid fever, and uncomplicated gonococcal infections and in the prophylaxis of bacterial infections in patients with neutropenia. These agents have the convenience of oral administration, favorable pharmacokinetic properties, and low toxicity profiles but should be used advisedly because indiscriminate use may result in the early emergence of resistance.

Persistence of Neisseria gonorrhoeae strains with decreased susceptibilities to ciprofloxacin and ofloxacin in Cleveland, Ohio, from 1992 through 1993

Twenty-five isolates of beta-lactamase-negative strains of Neisseria gonorrhoeae exhibiting decreased susceptibilities to ciprofloxacin (MIC, > or = 0.125 microgram/ml) were isolated from men with uncomplicated gonococcal urethritis in Cleveland, Ohio, from January 1992 through June 1993. The strains belonged to three auxotype-serovar classes: Pro-IB-1 (2 isolates), Pro-IB-2 (21 isolates), and Pro-IB-3 (2 isolates). MICs for strains were in the intermediate or resistant categories for penicillin, the intermediate or susceptible categories for tetracycline (with the exception of one strain that had acquired the 25.2-MDa TetM-containing plasmid) and cefoxitin, and the susceptible categories for ceftriaxone and cefixime (MICs, < or = 0.25 microgram/ml) and spectinomycin (MIC, < or = 256 micrograms/ml). MICs for strains were also in the susceptible category for ofloxacin (MIC, 0.25 microgram/ml) and in categories higher than susceptible for ciprofloxacin (MICs, 0.125 to 0.25 microgram/ml) and ofloxacin (MIC, 0.5 microgram/ml). The diameters of zones of inhibition for these strains ranged from 31 to 39 mm for ciprofloxacin to 28 to 35 mm for ofloxacin. The persistence of these strains over an 18-month period supports the need for routine sentinel surveillance and monitoring of gonococcal isolates, particularly posttreatment isolates, for resistance to quinolones when these agents are used for the primary therapy of uncomplicated gonorrhea.

Comparison of ciprofloxacin and ceftriaxone as single-dose therapy for uncomplicated gonorrhea in women

Although women bear the brunt of gonococcal infection-related morbidity, few large studies of gonorrhea treatment in women have been conducted. In a multicenter, double-blind, placebo-controlled trial, 181 evaluable women with uncomplicated gonorrhea were treated with ciprofloxacin (250 mg orally; 94 women) or ceftriaxone (250 mg intramuscularly; 87 women). Twenty-four percent of the participants were infected with antibiotic-resistant Neisseria gonorrhoeae. Cervical gonorrhea was cured in 100% (93 of 93) of the women treated with ciprofloxacin and 99% (83 of 84) receiving ceftriaxone. All pharyngeal (n = 5) or rectal (n = 20) infections treated with ciprofloxacin were cured, as were ceftriaxone-treated patients with pharyngeal (n = 6) or rectal (n = 21) infection. Geometric mean MICs (range) for 248 pretreatment isolates were: penicillin, 0.28 (0.015 to 8.0); tetracycline, 0.46 (0.06 to 4); ciprofloxacin, 0.003 (0.002 to 0.015); and ceftriaxone, 0.004 (0.001 to 0.125) microgram/ml. Both drugs were well tolerated. Despite the high prevalence of antibiotic-resistant gonococci in these populations, 250 mg of oral ciprofloxacin was as effective as an injection of ceftriaxone.

Recent developments in the treatment of sexually transmitted diseases

Recent changes in the treatment of sexually transmitted diseases include recognition of penicillin-resistant Neisseria gonorrhoeae, identification of Chlamydia trachomatis as the leading cause of bacterial genital infection in the United States, and the realization that the urethritis syndrome is often associated with multiple pathogens. There is currently no monotherapy that eradicates all STD pathogens. The role of fluoroquinolones in the treatment of STDs is still evolving. The investigational agent, temafloxacin, has good activity against gonococci, nongonococcal organisms, and, unlike other quinolones, against Bacteroides fragilis and other anaerobes. Norfloxacin, ciprofloxacin, enoxacin, ofloxacin, and temafloxacin single-dose therapy have demonstrated clinical efficacy for gonococcal infections in non-comparative and comparative trials, including bacterial eradication of isolates resistant to other agents.

Pharmacokinetic determination of relative potency of quinolone inhibition of caffeine disposition

Quinolone is reported to interact with caffeine, often resulting in an increase both in the plasma half-life and AUC, a decrease in total plasma clearance, and little change in the absorption rate constant and maximum plasma level. These complex changes in the pharmacokinetics of caffeine were analyzed experimentally and from published reports in order to determine the nature of the interaction, which is thought to be due to inhibition of caffeine metabolism by quinolones. A simple pharmacokinetic model for the caffeine-quinolone interaction was developed, which provides a unified method for evaluation and comparison of the effect of quinolones on the disposition of caffeine. The model is applicable to other methylxanthines, such as theophylline. The relative potency of the interactions of quinolones with caffeine in humans has been established as enoxacin (100), pipemidic acid (29), ciprofloxacin (11), norfloxacin (9) and ofloxacin (0).

Lectins and their application to clinical microbiology

Lectins are generally associated with plant or animal components, selectively bind carbohydrates, and interact with procaryotic and eucaryotic cells. Lectins have various specificities that are associated with their ability to interact with acetylaminocarbohydrates, aminocarbohydrates, sialic acids, hexoses, pentoses, and as other carbohydrates. Microbial surfaces generally contain many of the sugar residues that react with lectins. Lectins are presently used in the clinical laboratory to type blood cells and are used in a wide spectrum of applications, including, in part, as carriers of chemotherapeutic agents, as mitogens, for fractionation of animal cells, and for investigations of cellular surfaces. Numerous studies have shown that lectins can be used to identify rapidly certain microorganisms isolated from a clinical specimen or directly in a clinical specimen. Lectins have been demonstrated to be important diagnostic reagents in the major realms of clinical microbiology. Thus, they have been applied in bacteriology, mycology, mycobacteriology, and virology for the identification and/or differentiation of various microorganisms. Lectins have been used successfully as epidemiologic as well as taxonomic markers of specific microorganisms. Lectins provide the clinical microbiologist with cost-effective and potential diagnostic reagents. This review describes the applications of lectins in clinical microbiology.

Comparison of ofloxacin and ceftriaxone in the treatment of uncomplicated gonorrhea caused by penicillinase-producing and non-penicillinase-producing strains

Eighty-nine patients with uncomplicated gonorrhea, including 31 patients (34.8%) infected with penicillinase-producing strains of Neisseria gonorrhoeae, were treated with oral ofloxacin (single 400-mg dose) or intramuscular ceftriaxone (250-mg dose). All 47 patients who received ofloxacin and 41 of 42 patients who received ceftriaxone were cured.

Fluoroquinolone antimicrobial agents

The fluoroquinolones, a new class of potent orally absorbed antimicrobial agents, are reviewed, considering structure, mechanisms of action and resistance, spectrum, variables affecting activity in vitro, pharmacokinetic properties, clinical efficacy, emergence of resistance, and tolerability. The primary bacterial target is the enzyme deoxyribonucleic acid gyrase. Bacterial resistance occurs by chromosomal mutations altering deoxyribonucleic acid gyrase and decreasing drug permeation. The drugs are bactericidal and potent in vitro against members of the family Enterobacteriaceae, Haemophilus spp., and Neisseria spp., have good activity against Pseudomonas aeruginosa and staphylococci, and (with several exceptions) are less potent against streptococci and have fair to poor activity against anaerobic species. Potency in vitro decreases in the presence of low pH, magnesium ions, or urine but is little affected by different media, increased inoculum, or serum. The effects of the drugs in combination with a beta-lactam or aminoglycoside are often additive, occasionally synergistic, and rarely antagonistic. The agents are orally absorbed, require at most twice-daily dosing, and achieve high concentrations in urine, feces, and kidney and good concentrations in lung, bone, prostate, and other tissues. The drugs are efficacious in treatment of a variety of bacterial infections, including uncomplicated and complicated urinary tract infections, bacterial gastroenteritis, and gonorrhea, and show promise for therapy of prostatitis, respiratory tract infections, osteomyelitis, and cutaneous infections, particularly when caused by aerobic gram-negative bacilli. Fluoroquinolones have also proved to be efficacious for prophylaxis against travelers' diarrhea and infection with gram-negative bacilli in neutropenic patients. The drugs are effective in eliminating carriage of Neisseria meningitidis. Patient tolerability appears acceptable, with gastrointestinal or central nervous system toxicities occurring most commonly, but only rarely necessitating discontinuance of therapy. In 17 of 18 prospective, randomized, double-blind comparisons with another agent or placebo, fluoroquinolones were tolerated as well as or better than the comparison regimen. Bacterial resistance has been uncommonly documented but occurs, most notably with P. aeruginosa and Staphylococcus aureus and occasionally other species for which the therapeutic ratio is less favorable. Fluoroquinolones offer an efficacious, well-tolerated, and cost-effective alternative to parenteral therapies of selected infections.

Multicenter randomized study of single-dose ofloxacin versus amoxicillin-probenecid for treatment of uncomplicated gonococcal infection

The safety and efficacy of ofloxacin, 400 mg orally, were compared with those of amoxicillin, 3.0 g, plus probenecid, 1.0 g orally, as single-dose therapy in 201 heterosexual patients (101 men and 100 women) with uncomplicated gonococcal infection. Treatment groups were comparable in age, duration of symptoms, number of sexual partners within the previous month, and number of previous episodes of sexually transmitted diseases. The cure rate for men treated with ofloxacin was 98% (47 of 48), and that for women was 100% (52 of 52). Cure rates for both men and women treated with amoxicillin-probenecid were 96% (51 of 53 men; 46 of 48 women). All 13 patients with positive rectal cultures and 7 of 8 patients with positive pharyngeal cultures treated with ofloxacin were cured. Neither regimen reliably eradicated coexistent infection with Chlamydia trachomatis. The MIC of ofloxacin for all but two of 198 pretreatment isolates was 0.3 microgram/ml or less. The MIC of amoxicillin for 90% of isolates tested was 1.0 microgram/ml. Single oral doses of ofloxacin and of amoxicillin plus probenecid were equally effective for treatment of urethral and cervical gonorrhea. Ofloxacin appears promising as treatment for rectal and pharyngeal infection, but studies with larger numbers of patients with rectal or pharyngeal infection or both are required for confirmation. Relative contraindications in children and possibly pregnant women plus the potential for single-step, high-level resistance may limit the usefulness of quinolone therapy for gonorrhea.

[Multi-step increase in resistance of Neisseria gonorrhoeae isolates after repeated in-vitro subinhibitory concentrations of second-generation quinolones]

Five recent gonococcal isolates were exposed to subinhibitory concentrations of several antibiotics in vitro 25 times. In the presence of rifampicin all strains quickly became resistant. In the presence of penicillin, enoxacin and ciprofloxacin, antimicrobial susceptibility also decreased. Here development of resistance, however, corresponded to the multi- and not to the one-step type. It seems remarkable that even at the end of the experiments no strain grew at concentrations of ciprofloxacin exceeding 0.064 mg/l. In conclusion, quick development of resistance need not be expected after the introduction of newer quinolones into the therapy of gonorrhoea on a large scale.

Clinical overview of enoxacin

Enoxacin is a new fluoroquinolone that will be available as oral and intravenous preparations. This drug is bactericidal for a wide range of organisms, including Staphylococcus aureus, S. epidermidis, Enterobacteriaceae and Pseudomonas aeruginosa. In addition, Neisseria gonorrhoeae is exquisitely susceptible, as is Branhamella catarrhalis. The evaluation of the clinical activity of enoxacin is still relatively new, but published studies reveal a good deal of potential in the treatment of infections caused by susceptible bacteria in the urinary tract, upper and lower respiratory tracts, bones and joints, and the gastrointestinal tract. The general use of this drug has been associated with few adverse reactions. Further published data, as well as the results of comparative trials now in progress, will permit a thorough clinical evaluation of this useful drug.

Fluoroquinolone antibiotics. Microbiology, pharmacokinetics and clinical use

The newer fluoroquinolones are a major advance in antimicrobial chemotherapy. They inhibit the supercoiling activity of the DNA gyrase enzyme, thus exerting their antibacterial action on DNA and RNA synthesis, resulting in a biphasic response and killing of susceptible organisms. The newer fluoroquinolones have an extended antimicrobial spectrum compared to their older congeners, and are highly active against most Gram-negative pathogens including the Enterobacteriaceae and Pseudomonas aeruginosa. While Staphylococcus aureus and coagulase-negative staphylococci are usually susceptible to the fluoroquinolones, streptococci are generally more resistant and enterococci are resistant. All of the newer fluoroquinolones may be administered orally and most of them have been administered parenterally. They are widely distributed in the body, attaining therapeutic concentrations in most tissues. All of the fluoroquinolones have long half-lives and may be administered once or twice daily. The fluoroquinolones have proved effective in many infections, including uncomplicated or complicated urinary tract infections, respiratory tract infections, gonorrhoea, bacterial gastroenteritis, and soft tissue infections due to Gram-negative organisms. In general, success has been notable in the management of Gram-negative infections but less so with Gram-positive infections. Resistance has occurred and is proving a problem with P. aeruginosa in some cystic fibrosis patients, but as yet no plasmid-mediated resistance has developed. Cross-resistance occurs between the quinolones but only rarely with other classes of antibacterial drugs. The fluoroquinolones have an excellent safety record and their adverse effects, which include hypersensitivity reactions, dizziness, headache, gastrointestinal disturbance and minor haematological abnormalities are usually mild and transient. However, the fluoroquinolones have been found to damage juvenile weight-bearing joints in animals and are therefore only to be used with caution in children; transient arthralgia has been reported in a cystic fibrotic teenager on long term ciprofloxacin therapy. All of the fluoroquinolones except ofloxacin are associated with a variable increase in the serum concentration of theophylline, warfarin and caffeine. Thus, the fluoroquinolones are an attractive option in the management of many infections. Cost and possible resistance, however, should counsel caution in their use, and may limit them to situations where a cheaper antimicrobial of equivalent efficacy is not available.

Single dose oral norfloxacin or intramuscular spectinomycin to treat gonorrhoea (PPNG and non-PPNG infections): analysis of efficacy and patient preference

Norfloxacin, a new oral quinolone, was compared with intramuscular spectinomycin for treating culture proved gonorrhoea (caused by penicillinase producing strains of Neisseria gonorrhoeae (PPNG) and non-PPNG strains. A total of 547 infected men and women were randomly allocated to treatment with either single dose norfloxacin (800 mg by mouth) or spectinomycin (2 g intramuscularly). Patient preference for tablets or injections was noted at this visit. Patients returned four to eight days later for assessment of efficacy, safety, and preference. Of the 482 patients who attended follow up, all those treated with norfloxacin (94 infected with PPNG strains, 145 with non-PPNG strains) and all 82 infected with PPNG strains and treated with spectinomycin were cured. Of 161 infected with non-PPNG strains and treated with spectinomycin, 159 (99%) were cured. Side effects (headache, nausea, and sleepiness) occurred in three patients receiving norfloxacin and in 17 (16 pain at injection site, 1 giddiness) receiving spectinomycin. Most patients preferred tablets to injection both on day 1 (313 v 200) and at follow up (373 v 104). This study showed that norfloxacin was a highly effective alternative to spectinomycin, produced fewer side effects, and was the preferred mode of administration.

Enoxacin. A review of its antibacterial activity, pharmacokinetic properties and therapeutic use

Enoxacin is a new addition to the class of 4-quinolone antibacterial drugs. It has a broad spectrum of in vitro antibacterial activity, and is particularly potent against Gram-negative organisms and staphylococci. The pharmacokinetic profile of enoxacin is similar to that of ofloxacin, achieving higher plasma and tissue concentrations and possessing a longer half-life than norfloxacin or ciprofloxacin. In comparative studies, clinical and/or bacteriological efficacy was comparable or (in studies which statistically analysed the results) not significantly different between enoxacin and amoxycillin in acute cystitis, acute Gram-negative exacerbations of chronic bronchitis and acute or chronic otitis media, between enoxacin and cephalexin in skin, skin structure and soft tissue infections, between enoxacin and trimethoprim in acute cystitis, between enoxacin and co-trimoxazole in complicated urinary tract infection and between enoxacin and pipemidic acid in suppurative otitis media. Significantly (p less than 0.01) more clinical and/or bacteriological cures were effected by enoxacin than pipemidic acid in acute cystitis and complicated urinary tract infection. In uncomplicated gonococcal infections single oral doses of enoxacin were effective in over 90% of patients. Enoxacin is a well-tolerated, orally active broad spectrum antibacterial drug which should prove a worthwhile alternative to currently available antibacterial therapy.

Randomized comparative study of 0.5 and 1 g of cefodizime (HR 221) versus 1 g of cefotaxime for acute uncomplicated urogenital gonorrhea

Uncomplicated urogenital and concomitant oropharyngeal gonorrhea in 424 male and female patients was treated in a randomized comparative study with 0.5 g of cefodizime (89 men and 54 women), 1 g of cefodizime (87 men and 52 women), or 1 g of cefotaxime (86 men and 56 women). The cure rates were 100% for men and women in the group given 0.5 g of cefodizime, 100% for men and women in the group given 1 g of cefodizime, and 99% for men and 100% for women in the group given 1 g of cefotaxime. The MICs of cefodizime and cefotaxime for the isolate of Neisseria gonorrhoeae ranged from 0.004 to 0.06 micrograms/ml. Chlamydia trachomatis was isolated before treatment in 15% and after treatment in 13% of all patients. Side effects, such as nausea, diarrhea, abdominal pain, genital candidiasis, and pain at the site of injection, developed in 4% of the patients given cefodizime. Side effects, such as vertigo, genital candidiasis, fatigability, and diarrhea, developed in 4% of the patients treated with cefotaxime. In both groups of patients, the side effects were mild and transient. Cefodizime and cefotaxime are safe and effective agents in the treatment of uncomplicated urogenital gonorrhea.

Quinolones in the treatment of gonorrhoea and Chlamydia trachomatis infections

The results of two therapeutic trials in female patients with uncomplicated urogenital gonorrhoea (A) and in male patients with uncomplicated urethral gonorrhoea (B) treated with either 200 mg and 400 mg enoxacin orally, of one therapeutic trial in male patients with uncomplicated urogenital gonorrhoea treated with either 250 mg or 500 mg ciprofloxacin orally (C) and of one therapeutic trial in male patients with non-gonococcal urethritis (NGU) treated with ciprofloxacin 1 g daily during seven days (D) are presented and compared with the results of other investigators. The cure rate in study A was 100% (n = 40) in the 400 mg group and 95.7% (n = 46) in the 200 mg group. The cure rate in study B was 92% (n = 78) in the 400 mg group and 90% (n = 77) in the 200 mg group. In both studies no antichlamydial effect of enoxacin was observed. The cure rates in study C were 100% with 250 and 500 mg. An antichlamydial effect seemed to be present. In studies A, B and C side effects were minor and rare and were mainly nausea and headache. In study D (100 patients suffering from NGU) disappearance of Chlamydia trachomatis and Ureaplasma urealyticum one day after the end of treatment was observed in 29 of 32 (91%) and 28 of 32 (88%) cases, respectively. Pyuria disappeared in 44% and 74% of the patients showed clinical cure. However, two weeks after the end of treatment Chlamydia trachomatis and Ureaplasma urealyticum were observed in respectively six and eight cases. In 30% pyuria was still absent. Side effects were only minor.(ABSTRACT TRUNCATED AT 250 WORDS)