Intraprostatic concentration of ciprofloxacin and its activity against urinary pathogens

Ciprofloxacin as a prophylactic agent against prostate cancer: a "two hit" hypothesis

More evidence indicate that prostate inflammation can lead to prostate cancer development. Prostate cancer affects elderly men. Prostate cancer prophylaxis is an important issue because life expectancy is very long now. Ciprofloxacin is an antibacterial agent used mainly in urinary tract infections and prostate inflammation. This drug acts also against cancer cells by the inhibition of topoisomerase II. These properties should allow it to inhibit the development of prostate cancer. Firstly, ciprofloxacin can stop the acute and chronic prostate inflammation which can lead to cancer development. Secondly, ciprofloxacin can potentially kill prostate cancer cells in their early stage of development. Ciprofloxacin accumulates mainly in the prostate after oral intake thus ciprofloxacin seems to be a perfect candidate as a prophylactic agent.

Parallel evolution and local differentiation in quinolone resistance in Pseudomonas aeruginosa

The emergence and spread of antibiotic resistance in pathogens is a major impediment to the control of microbial disease. Here, we review mechanisms of quinolone resistance in Pseudomonas aeruginosa, an important nosocomial pathogen and a major cause of morbidity in cystic fibrosis (CF) patients. In this quantitative literature review, we find that mutations in DNA gyrase A, the primary target of quinolones in Gram-negative bacteria, are the most common resistance mutations identified in clinical samples of all origins, in keeping with previous observations. However, the identities of non-gyrase resistance mutations vary systematically between samples isolated from CF patients and those isolated from acute infections. CF-derived strains tend to harbour mutations in the efflux pump regulator nfxB, while non-CF strains tend to bear mutations in the efflux regulator mexR or in parC, which encodes one of two subunits of DNA topoisomerase IV. We suggest that differences in resistance mechanisms between CF and non-CF strains result either from local adaptation to different sites of infection or from differences in mutational processes between different environments. We further discuss the therapeutic implications of local differentiation in resistance mechanisms to a common antibiotic.

Prostatitis: US perspective

The diagnosis and management of prostatitis syndromes is a challenge to the clinician. Careful history and examination of the prostate fluid and quantitative segmented bacteriologic cultures will lead to proper categorization into the recognized forms of the prostatitis syndrome. Antimicrobial therapy is effective in the majority of men with acute and chronic bacterial prostatitis (CBP). Fluoroquinolone agents appear to have an increasingly important role in this regard, although a randomized, prospective, double-blind study is still lacking. Alpha-1-selective blocking agents may relieve symptomatology of chronic pelvis pain syndrome (CPPS). Other non-prostatic sources of voiding symptoms should be sought and ruled out, especially malignancy or inflammatory disorders.

Clinical pharmacokinetics of parenterally administered danofloxacin in cattle

Danofloxacin is a new fluoroquinolone antibacterial, developed specifically for veterinary use. Its in vitro activity and pharmacokinetic properties have been investigated to assess its potential for use in the therapy of respiratory disease in cattle. The minimum inhibitory concentration of danofloxacin against 90% (MIC90) of contemporary European and North American field isolates of Pasteurella haemolytica, Pasteurella multocida and Haemophilus somnus, the most important bacterial respiratory pathogens of cattle, was 0.125 micrograms/ml. The plasma and lung kinetics of danofloxacin following parenteral administration of 1.25 mg/kg were evaluated in two studies. Danofloxacin was rapidly absorbed following intramuscular and subcutaneous injection and bioavailability was virtually complete (101% and 94% respectively). Plasma concentration profiles of danofloxacin were similar for intramuscular and subcutaneous routes with no significant differences in the area under the plasma concentration-time curves (AUC) following one, three or five consecutive daily doses, although slightly higher peak plasma concentrations were achieved by the intramuscular route. Following intramuscular administration, the mean peak lung concentration of danofloxacin was 4.1 times greater than that of plasma. Similarly, the AUC for lung tissue was 3.7 times greater than that for plasma. These data indicate that danofloxacin should be particularly appropriate for the therapy of bacterial respiratory disease in cattle.

Use of quinolones in treatment of prostatitis and lower urinary tract infections

The newer quinolones, ciprofloxacin, enoxacin, fleroxacin, lomefloxacin, norfloxacin, ofloxacin and pefloxacin are highly effective antimicrobial agents against the majority of bacteria responsible for urinary tract infections and bacterial prostatitis. The pharmacokinetic properties of these agents after oral administration result in high concentrations in human urine, as well as in prostatic fluid and prostatic tissue. Ciprofloxacin, enoxacin and lomefloxacin produce the highest concentrations in prostatic tissue, followed by norfloxacin, ofloxacin and fleroxacin. More than 400 patients with chronic bacterial prostatitis have been treated with one of the newer quinolones in varying doses for 10 to 84 days. The results indicate a cure rate of approximately 70%, although the follow-up period is quite variable in these studies. Clinical trials of short-term (single dose vs three days) therapy with the newer quinolones conducted in women with uncomplicated lower urinary tract infections were reviewed. Although bacteriologic cure rates were high with single doses of ciprofloxacin, fleroxacin, norfloxacin, ofloxacin and pefloxacin, approximately one in five women with suspected uncomplicated lower urinary tract infection experience failure of single-dose therapy. In contrast, a three-day regimen with these agents is more effective than a single-dose in the treatment of uncomplicated lower urinary tract infections in women.

Prostatic abscess caused by Streptococcus mutans

The first reported case of prostatic abscess caused by Streptococcus mutans isolated in pure culture is described. Urethral dilation for obstruction was unsuccessful, so suprapubic cystostomy was performed. Perineal aspiration under ultrasonic guidance resulted in 10 mL of pus containing pure Strep mutans. Diagnosis of prostatic abscess is difficult since the clinical manifestations are nonspecific.

Extravascular penetration of ciprofloxacin. A review

The pharmacokinetics of ciprofloxacin after oral and intravenous administration have been studied extensively, and the results have been published worldwide. This paper serves as a review of the pharmacokinetics of ciprofloxacin, with specific reference to its penetration into body fluids and tissues. Ciprofloxacin has a protein binding of approximately 30% and penetrates well into tissues. For instance, the total concentration (area under the serum concentration-time curve) in peripheral human lymph is 70% of the serum values, and the peak level in lymph appears with 1-2 hr. The corresponding value for suction skin blisters is 60% and for inflammatory blisters 120%. Ciprofloxacin is concentrated in white blood cells, lung, prostate, and kidney and reaches concentrations above serum in many other tissues as well. Urine concentrations are up to 100 times those in serum. The levels in bile are comparable or only slightly higher (less than or equal to x 10) than serum levels. The penetration into cerebrospinal fluid (CSF) is low; the CSF levels are 4-10% of the serum levels in noninflammatory CSF and 30-50% in CSF from patients with meningitis.

Ciprofloxacin in management of urinary tract infection

Ciprofloxacin is a new quinolone derivative which is particularly well adapted for the treatment of bacterial urinary tract infection. Virtually all uropathogens are susceptible, and the development of resistance is uncommon. Its pharmacokinetic characteristics reveal that effective concentrations of the drug are easily achieved with twice a day oral therapy in the blood, urine, kidneys, and prostate--even in advanced renal failure. The drug is well tolerated, even with prolonged courses of therapy. It will be particularly useful in the treatment of antibiotic-resistant, complicated, and/or prostatic infection.

Clinical pharmacokinetics of the newer antibacterial 4-quinolones

Structural modification of the so-called 'first-generation' or 'urinary' quinolones has led to a considerable increase in their intrinsic antibacterial activity, together with marked changes in the pharmacokinetic properties. Tissue penetration is the most notable change, and the newer quinolones are comparable with the newer broad spectrum beta-lactams in their clinical spectrum of activity. Marketed compounds in the 4-quinolones group include pefloxacin, ofloxacin, enoxacin, ciprofloxacin and norfloxacin; many more compounds are in various stages of research and development. The 4-quinolones act by inhibition of bacterial DNA gyrase, a process which is pH and concentration dependent. The bactericidal activity can be partly abolished if protein synthesis is inhibited by chloramphenicol, or if RNA synthesis is inhibited by rifampicin (rifampin). The antibacterial spectrum of activity includes methicillin- and gentamicin-resistant staphylococci, multiresistant non-fermenters, all Enterobacteriaceae, Legionella, Neisseria species, Branhamella and Haemophilus influenzae. With the exception of norfloxacin, which is only 30 to 40% bioavailable from the oral route, the 4-quinolones are 80 to 100% bioavailable, absorption occurring within 1 to 3 hours. Food does not significantly alter Cmax, AUC or elimination half-life, although tmax, may be increased. The 4-quinolones are widely distributed throughout the body, with volumes of distribution greater than 1.5 L/kg. Protein binding is less than 30% in most cases. Penetration into most tissues is good. With the exception of ofloxacin and lomefloxacin (NY 198), which are metabolically stable, metabolism of the 4-quinolones occurs primarily at the C7 position in the piperazinyl ring. Biotransformation is extensive (85%) with pefloxacin, medium (25 to 40%) with ciprofloxacin and enoxacin, and low (less than 20%) with norfloxacin. Elimination half-lives vary between 3 and 5 hours (ciprofloxacin) and 8 to 14 hours (pefloxacin). Biliary concentrations of the 4-quinolones are 2 to 10 times greater than those in serum or plasma, with several compounds undergoing enterohepatic circulation. There is some evidence that ciprofloxacin, norfloxacin, ofloxacin and enoxacin have an active renal tubular excretion pathway. In impaired renal function, reduction of the glomerular filtration rate below 30 ml/min (1.8 L/h) is associated with an increase in elimination half-life and AUC, and a decrease in renal and total clearance of the 4-quinolones, and a decrease in 24-hour urinary recovery.(ABSTRACT TRUNCATED AT 400 WORDS)

Ciprofloxacin: chemistry, mechanism of action, resistance, antimicrobial spectrum, pharmacokinetics, clinical trials, and adverse reactions

Ciprofloxacin, considered a benchmark when comparing new fluoroquinolones, shares with these agents a common mechanism of action: inhibition of DNA gyrase. While ciprofloxacin demonstrated a fairly good activity against gram-positive bacteria, it is against gram-negative organisms that it proved to be more potent than other fluoroquinolones. It is the most active quinolone against Pseudomonas aeruginosa, with MIC90s on the order of 0.5 micrograms/ml. When given orally, ciprofloxacin exhibited 70% bioavailability and attained peak serum levels ranging between 1.5 and 2.9 micrograms/ml after a single 500-mg dose. Nineteen percent of an oral dose was excreted as metabolites in both urine and feces. In most cases, body fluids and tissue concentrations equaled or exceeded those in concurrent serum samples. In clinical trials, oral and intravenous ciprofloxacin yielded similar clinical and bacteriologic results compared to standard therapy in a wide array of systemic infections, including lower and upper urinary tract infections; gonococcal urethritis; skin, skin structure, and bone infections; and respiratory tract and gastrointestinal tract infections. Major benefits with the oral form of this quinolone are expected in chronic pyelonephritis and bone infections, and in pulmonary exacerbations in patients with cystic fibrosis. Emergence of ciprofloxacin-resistant microorganisms has been noted in clinical practice, primarily Pseudomonas aeruginosa and Staphylococcus aureus. The most frequent side effects are related to the gastrointestinal tract; but attention should be given to adverse central nervous system effects.

Ciprofloxacin concentrations in tonsils following single or multiple administrations

Penetration of ciprofloxacin into human tonsils was studied in 20 adult humans undergoing tonsilectomy. Ten patients received a single intravenous infusion of 200 mg ciprofloxacin within 15 min (group A) and 14 patients were treated orally for three days with 500 mg ciprofloxacin b.i.d. prior to a preoperative infusion of 200 mg (group B). Ciprofloxacin concentrations in serum and tonsils were determined microbiologically. Mean ciprofloxacin serum concentrations did not differ significantly between both groups. Similarly, mean distribution ratios between tonsils and serum were not dissimilar, being on average 150% irrespective of whether the drug was administered once or repeatedly. Thus, a significant accumulation of ciprofloxacin was not observed either in the intravascular or in the extravascular space.

Treatment of chronic bacterial prostatitis with ciprofloxacin

Thirty two patients with proven chronic bacterial prostatitis were treated with ciprofloxacin 500 mg twice daily orally for four weeks. The causative organisms, cultured from prostatic fluid were Enterobacteriaceae (19 patients), enterococci (9), staphylococci (4), streptococci (3), non-fermentative Gram-negative rods (2) and anaerobic bacteria (9). Nineteen patients had pure cultures, 13 mixed cultures. The susceptibility of all organisms to ciprofloxacin, sulfamethoxazole, trimethoprim and doxycyclin was determined by agar dilution. The effect of therapy was measured by clinical parameters and by repeated cultures of prostatic fluid during and after therapy up to six months. Clinical cure (at one month after therapy) was obtained in 22 patients, improvement in seven; two patients did not respond, one patient had to stop during therapy because of severe nausea. No other side effects were noted. Ciprofloxacin may be a useful alternative drug in the treatment of prostatitis.

Fleroxacin (Ro 23-6240) distribution in canine prostatic tissue and fluids

The distribution of fleroxacin (Ro 23-6240) in canine prostatic tissue and fluids was investigated under steady-state conditions during intravenous infusion. Mean ratios of fleroxacin concentration in tissue and fluids over concentration in plasma were 1.57 +/- 0.25 for prostatic tissue, 1.12 +/- 0.28 for prostatic secretion, and 0.93 +/- 0.14 for prostatic interstitial fluid. These levels and concentrations in urine were several times higher than the MIC for most pathogens that cause chronic bacterial prostatitis and urinary tract infection. The MICs for several isolates of Escherichia coli were only slightly affected by canine prostatic secretion, human prostatic tissue extract, and human urine. Clinical trials with fleroxacin appear justified for chronic bacterial prostatitis and urinary tract infection.

Review of the 4-quinolones

Improvements in antimicrobial activity and pharmacokinetics have moved the 4-quinolones into the forefront of antibiotic research. The 4-quinolones are analogues of nalidixic acid, and there are presently at least six agents in this group under investigation in the United States. It is difficult to generalize their clinical usefulness, since these agents exhibit different pharmacokinetic profiles, antimicrobial activity (with varied minimum inhibitory concentrations among similar organisms), and dosage regimens. The 4-quinolones are potential therapeutic alternatives for infections caused by a variety of organisms. They include: Neisseria gonorrhoeae; Pseudomonas aeruginosa; Haemophilus influenzae; Staphylococcus aureus; common enteric pathogens (salmonella, shigella, campylobacter, etc); and intracellular bacteria (legionella, chlamydia, mycobacteria, etc). Clinical efficacy has been demonstrated in urinary tract infections, respiratory tract infections, and sexually transmitted diseases. Future studies will undoubtedly demonstrate effectiveness in numerous additional infectious processes. The purpose of this article is to compare the 4-quinolones in regards to pharmacokinetics and spectrum of activity and review the clinical studies involving these agents.

The possible role of quinolones in yersiniosis

The in vitro susceptibility of 135 strains of Yersinia enterocolitica was tested by agar dilution. About 85% of the strains were susceptible to trimethoprim (1 mg/L), tetracycline (4 mg/L), chloramphenicol (4 mg/L) and cefuroxime (8 mg/L); 90 to 100% to piperacillin (16 mg/L), cefotaxime (8 mg/L) and gentamicin (1 mg/L); 100% to ciprofloxacin (less than or equal to 0.016 mg/L), ofloxacin (0.06 mg/L) and pefloxacin (0.12 mg/L). The outcome of 88 patients, treated for various forms of yersiniosis, showed 15% failure for trimethoprim or co-trimoxazole and tetracycline and 70% failure for cephalosporins and aminoglycoside-beta-lactam combinations. Four patients were successfully treated with ciprofloxacin 500 mg orally or 300 mg intravenously administered twice daily for up to 6 weeks.

Concentration of ciprofloxacin in human prostatic tissue after oral administration

Concomitant concentrations of ciprofloxacin in serum, urine, and prostatic tissue were determined in 15 patients after single oral doses of 750 mg. Levels in tissue ranged from 0.6 to 4.18 micrograms/g, and therapeutic concentrations were demonstrable for up to 9 h after administration. The mean ratio of tissue to serum concentration was 0.93 +/- 0.08 (standard error).

Evaluation of ciprofloxacin 500 mg twice daily for one week in treating uncomplicated gonococcal chlamydial, and non-specific urethritis in men

Ciprofloxacin, a quinolone antibacterial, was evaluated in the treatment of gonococcal, chlamydial, gonococcal and chlamydial, and non-gonococcal non-chlamydial urethritis. The dosage regimen used was 500 mg orally twice a day for seven days. Of the 56 patients evaluated 22 had gonococcal infection only, 13 were infected with Chlamydia trachomatis only, seven had combined infection, and 14 were harbouring neither of these organisms. Neisseria gonorrhoeae was cleared in all the 29 patients with or without chlamydial infection. Of those who denied having sexual intercourse during the follow-up period, post gonococcal urethritis (PGU) developed in 12 (63%) out of 19, C trachomatis was isolated again from 11 (78%) out of 14, and urethritis recurred in five (55%) out of nine patients with non-gonococcal non-chlamydial infection. There was also evidence that the dosage regimen used was only partially effective against Ureaplasma urealyticum.

Single and multiple dose pharmacokinetics of ciprofloxacin

Penetration of ciprofloxacin into nasal secretion was studied in 20 healty volunteers to whom 500 mg oral ciprofloxacin was administered twice daily for eight days. Nasal secretion and blood samples were collected following the 1st and 15th dose and samples assayed microbiologically. Absolute concentrations of ciprofloxacin in serum and nasal secretion as well as kinetic parameters indicate that repeated administration did not result in significantly increased serum or nasal secretions levels although there was a tendency towards slight drug accumulation. The rate of penetration of ciprofloxacin into nasal secretion was 73% following the first oral dose and 90% following the 15th oral dose.

Fluorinated quinolones. A review of their mode of action, antimicrobial activity, pharmacokinetics and clinical efficacy

Quinolones, chemically related to nalidixic acid, have a strong and rapid bactericidal action against Gram-negative bacteria, including Ps. aeruginosa, some Mycobacteria, Legionella and Staphylococci. Streptococci and anaerobic bacteria are usually less sensitive. The quinolones exert their bactericidal action through inhibition of the enzyme DNA gyrase. Quinolones are absorbed for 50-100% from the gastro-intestinal tract, their volume of distribution is generally high (2 l/kg) and high concentrations are reached in almost all organs. The elimination half-lives range from 4 to 14 h. The efficacy of quinolones in urinary tract infections has been shown in many studies. They also seem to be effective in many serious infections. In animal studies their efficacy was generally equal or superior to aminoglycosides. Until now only mild and infrequent side effects have been reported.

Quantitative determination of ofloxacin, ciprofloxacin, norfloxacin and pefloxacin in serum by high pressure liquid chromatography

A simple sensitive HPLC method for the analysis of ciprofloxacin, norfloxacin, ofloxacin and pefloxacin in serum is described. The quinolones were extracted using dichloromethane under neutral conditions, followed by drying under nitrogen and dissolving in mobile phase before chromatographic analysis. The stationary phase consisted of a stainless steel column with Nucleosil CI8 (5 microns), and a mobile phase of 0.04 M phosphoric acid, tetrabutylammoniumiodide as ion-pairing reagent and methanol (pH 2.2). UV absorbance was used for detection. The method was shown to be linear, quantitative and reproducible in the therapeutic range of each of these quinolones. Serum levels of ofloxacin and ciprofloxacin were determined and compared to those found by a microbiological assay. Good correlation was found for the assay of ciprofloxacin as well as for ofloxacin.

Ciprofloxacin pharmacokinetics in patients with cystic fibrosis

The pharmacokinetics of ciprofloxacin were studied in cystic fibrosis patients and healthy volunteers following oral administration of 500 mg and 1000 mg. Serum kinetics as well as urinary recovery were monitored. As the body weights of cystic fibrosis patients and the healthy volunteers differed significantly, kinetic parameters were calculated on the basis of a constant relative dose in mg/kg body weight. Neither serum kinetics nor urinary recovery differed significantly between the two groups, as indicated by the serum concentration versus time curves ranging from 1.1 to 1.4 mg X h/l, the elimination half-life of 4.4 to 5.1 h and the 24 h urinary recovery which amounted to 35% to 41% of the dose administered. Serum concentrations were linearly proportional to the doses administered. Sputum concentrations were monitored in cystic fibrosis patients. Again, ciprofloxacin sputum levels were linearly proportional to the doses and were within the same range as serum concentrations. Thus, ciprofloxacin kinetics are not altered in cystic fibrosis patients as compared to healthy volunteers.

Tissue distribution of ciprofloxacin following oral and intravenous administration

Ciprofloxacin distribution in muscle, subcutaneous fat and perirenal and perivesical fat was studied following a single i.v. bolus injection of 100 mg or oral administration of 500 mg. Levels in muscle were on average 0.75 mg/kg; diffusion into muscle was rapid, whereas elimination from muscle was slow. Similar peak levels were recorded in fatty tissues. However, penetration into subcutaneous fat in particular may be delayed in individual cases. Following an initial lagphase of up to one hour after i.v. injection, ciprofloxacin distribution was as efficient in these patients as in the others. Tissue levels following oral administration were monitored 12 hours after intake. On average, ciprofloxacin concentrations in serum, muscle and perirenal fat were 0.17 mg/l, 0.20 mg/kg and 0.11 mg/kg, respectively. Thus, ciprofloxacin is distributed effectively throughout the extravascular space following i.v. as well as oral administration.