Safety and efficacy of the antiseptic chlorhexidine gluconate

Chlorhexidine gluconate, an antiseptic for the skin, has recently been investigated in a series of clinical studies on its safety and efficacy. By using standard methods, Hibiclens, Hibitane tinted tincture and 0.5 per cent aqueous chlorhexidine gluconate were shown to have an extremely low potential for the production of irritation, allergic contact sensitization, photoallergic contact sensitization and phototoxicity. In the glove fluid test for efficacy against resident flora of the hand, Hibiclens produced log10 reductions over the control of 1.9398, 2.5371 and 2.6885 for test days 1, 2 and 5, respectively. Corresponding reductions for Hibitane tinted tincture were 3.6903, 4.0984 and 4.1253 and for the aqueous formulation, 1.5003, 1.5721 and 1.8692. In a transient flora skin contamination study, Serratia marcescens was applied at an average level of 6.8363 log10 organisms per milliliter to persons' hands, after which a 15 second Hibiclens hand wash was performed. Following five of these contaminations and hand washes, there was an over-all log10 reduction in recoverable Serratia of 3.8500. Counts were further determined after ten, 15, 20 and 25 contaminations and hand washes, resulting in corresponding reductions of 4.2649, 4.6661, 4.8501 and 5.1725, respectively. Chlorhexidine gluconate offers an alternative to available antiseptics for the skin. It has been shown to be a fast acting, broad spectrum antimicrobial agent, with an extremely low potential for eliciting dermal reactions.     

Two patients with chlorhexidine allergy--anaphylactic reactions and eczema

A 14 year-old girl experienced a combined delayed and immediate type of allergy to chlorhexidine. She first developed an eczematous reaction in the face following the long-term application of an antiacne preparation. Use test (repeated Open Application Test, ROAT) on the forearm was positive. Epicutaneous tests with 1% chlorhexidine gluconate and acetate were both positive. About six months later she developed an urticarial rash and syncope after cleansing the skin with chlorhexidine gluconate. Prick tests were positive to 0.05% chlorhexidine gluconate and to 0.01% of the acetate solution. A 30 year-old man developed anaphylactic symptoms following treatment with an antiseptic dental gel containing 1% chlorhexidine gluconate. Prick test was positive to the gel and to chlorhexidine gluconate 0.5%.     

Efficacy evaluation of a 4% chlorhexidine gluconate as a full-body shower wash

A 4% chlorhexidine gluconate (Xttrium Laboratories, Chicago, Ill.) was used in a shower bath application to evaluate its merits in reducing resident skin microorganisms. Five volunteers completed a 14-day microbial stabilization period, a 7-day baseline period, and a 5-day test period. Subjects followed a standard protocol, performed five shower washes and were sampled at both the abdominal and inguinal regions immediately after the shower wash as well as at 3 and 6 hours later on days 1, 2, and 5. Chlorhexidine gluconate provided significant microbial reductions from baseline, with greater reductions noted as the study progressed. Use of chlorhexidine gluconate in a shower wash application in conjunction with a preoperative skin-preparation procedure may reduce the probability of surgically associated infections.     

Cost analysis for total hip arthroplasty by measurement of time and material expenditure

BACKGROUND AND OBJECTIVES: An estimated 4 million new cases of chlamydial infection occur each year. This experiment assessed the effects of a vaginally applied gel formulation of 0.25% chlorhexidine gluconate on chlamydial infection and on the vaginal ecosystem. STUDY DESIGN: Twelve monkeys were treated with a single application of 0.25% chlorhexidine gluconate. These animals were assessed for changes in vaginal flora before and at 30 minutes, 1 day, and 2 days postapplication by microbiologic analysis. Cervical and vaginal tissues were assessed by colposcopy at each time point. Five monkeys received a single application of 0.25% chlorhexidine gluconate gel followed (30 minutes) by a cervical inoculation with Chlamydia trachomatis. Four monkeys were inoculated with Chlamydia only. Cervicovaginal tissues were assessed via modified colposcopy, vaginal swabs were collected for assessment of vaginal flora, and cervical swabs were collected for detection of Chlamydia (culture/ligase chain reaction) at baseline and days 1, 2, and 7 postinoculation. RESULTS: Changes in vaginal flora were minimal in all monkeys. Application of 0.25% chlorhexidine gluconate did not affect adversely vaginal colonization by lactobacilli. All chlamydial infection control monkeys were infected, whereas none of the five monkeys pretreated with chlorhexidine gluconate were positive for C. trachomatis by culture or ligase chain reaction. Colposcopic observations remained largely unchanged in all groups. CONCLUSIONS: A 0.25% chlorhexidine gluconate gel was protective against chlamydial infection in all animals tested, had no adverse effect on the vaginal flora, and had minimal effect on cervicovaginal tissues after a single application.     

History of the University Clinic of Dermatology and Venereology in Graz. A review of 125 years (1873-1998)

An outbreak of Serratia marcescens infections occurred in a university tertiary-care hospital. Alcohol-free chlorhexidine solutions were contaminated with S marcescens. The majority of patient and chlorhexidine strains had similar pulsed field-gel electrophoresis banding patterns. Chlorhexidine was recalled, and the rate of S marcescens isolation returned to baseline. Chlorhexidine without alcohol should not be used as an antiseptic.     

Effects of a protective foam on scrubbing and gloving

OBJECTIVE: To test the effects of a skin protectant on surgical scrub and glove integrity. DESIGN: Forty-nine healthy adult volunteers were assigned (12 subjects per group) to apply a protective foam (DermaMed; Benchmark Enterprises, Salt Lake City, Utah) in conjunction with surgical scrub in one of the following formulations: 70% isopropyl alcohol, a liquid detergent base containing 4% chlorhexidine gluconate, a liquid detergent base containing 7.5% povidone-iodine, or a nonantimicrobial liquid soap (control). According to a standard protocol, subjects performed a surgical scrub on 3 days (every other day). Foam was applied after surgical scrub on day 1 and before surgical scrub on day 3. No foam was applied on day 2. Subjects were gloved for 2 hours after surgical scrub. SETTING: Laboratory setting. RESULTS: On all test days, there were significant differences in bacterial reduction by products (chlorhexidine gluconate or alcohol > povidone-iodine > control). When controlling for baseline counts and products used, there were no significant differences in colony-forming unit counts on hands with or without foam immediately after scrubbing or at 2 hours after scrub on gloved or ungloved hands, nor were there differences in glove leakage rates when foam was on hands. CONCLUSIONS: Such protectants can be used without detrimental effects to scrub effectiveness or glove integrity.     

Hereditary motor and sensory neuropathy with spastic paraplegia and optic atrophy: report on a family

To determine the effect of RGP contact lens solution on corneal epithelial wound healing, the following solutions including Soaclens, Contopharma GPHCL-S, Boston condition, Bausch & Lomb condition and Duracare were applied on corneal epithelial wounds of enucleated pig eyes to evaluate possible cytotoxicity of RGP solutions. The wounds, created by excimer laser, were 1.5mm in diameter with 70 microns in depth. The eyeballs were maintained in an incubator using a perfusion system. After twenty-four hours, a score from 3 to 0 was given depending on the size of defect from absence of healing to completely healing. The average scores of the epithelial defect in each group are: Soaclens: 0.38 +/- 0.74; GPHCL-S: 0.63 +/- 0.52; Boston condition: 0.38 +/- 0.52; Bausch & Lomb condition: 0.25 +/- 0.46 and Duracare: 2.38 +/- 0.52. Most of the epithelial wounds healed with one exception, the eyeballs which received Duracare still had large defects. The difference of scores between Duracare and other groups are statistically significant. Duracare, which contains benzalkonium chloride, may be responsible for retarded wound healing.     

Ocular characteristics associated with rigid gas-permeable lens adherence

PURPOSE: Rigid gas-permeable (RGP) lens adherence after overnight lens wear is clearly a patient-dependent phenomenon. However, no previous study has attempted to determine whether specific ocular characteristics are associated with an increased frequency of lens adherence. METHOD: In this study, clinically applicable tests were used to measure a range of ocular characteristics, including central and peripheral corneal curvature, tear film status, eyelid characteristics, central corneal thickness, and ocular rigidity in a group of 22 young adult subjects for whom reliable estimates for frequency of overnight RGP lens adherence had been obtained from earlier studies. RESULTS: Linear discriminant analysis revealed that a higher frequency of lens adherence was associated with lower ocular rigidity, thinner central corneas, greater eyelid tension, and lower amounts of corneal astigmatism. CONCLUSIONS: These findings suggest a clinical approach for identifying patients who may develop clinically significant lens adherence during RGP extended wear, and also provide support for the "thin film adherence" theory of RGP lens adherence.     

Effect of proteolysis on the state of lipid phase in rat brain synaptosomal membranes

Polymethylmethacrylate (PMMA) contact lenses can alter corneal shape and induce corneal warpage or distortion. The purpose of our study was to determine the effects on the corneal topography after immediate refitting of long-term PMMA contact lens wearers into rigid gas permeable (RGP) materials. Six eyes with contact lens induced corneal warpage from PMMA contact lenses were assessed using the Topographical Mapping System-1. Statistical analysis was performed for the following variables prior to and approximately 6 months after contact lens refitting: best spectacle visual acuity, manifest refraction, surface regularity index, surface asymmetry index, keratometry, and simulated keratometry. Best spectacle visual acuity improved an average of 1.8 +/- 1.0 (mean +/- SD, P < 0.05) lines of Snellen visual acuity, while refraction did not change appreciably. The surface regularity index diminished by 0.51 +/- 0.32 (P = 0.01). The surface asymmetry index improved by 0.32 +/- 0.26 (P < 0.05). There was a good correlation between keratometry and simulated keratometry, and neither changed significantly after refitting with RGP contact lenses. All general topographic patterns remained unchanged throughout the study. Immediate refitting of long-term PMMA contact lens wearers into RGP materials of similar fit allows a slightly more regular and symmetric central corneal shape, which can result in improved spectacle visual acuity. The general corneal topographic patterns of contact lens induced corneal warpage did not change or improve after refitting to RGP material.     

Antibacterial effects of endodontic irrigants on black-pigmented gram-negative anaerobes and facultative bacteria

The antibacterial effect of endodontic irrigants was evaluated against four black-pigmented Gram-negative anaerobes and four facultative anaerobic bacteria by means of the agar diffusion test. All solutions used were inhibitory against all bacterial strains tested. A 4% NaOCl solution provided the largest average zone of bacterial inhibition of this study that was significantly superior when compared with the other solutions, except 2.5% NaOCl (p < 0.05). Based on the averages of the diameters of the zones of bacterial growth inhibition, the antibacterial effects of the solutions could be ranked from strongest to weakest as follows: 4% NaOCl; 2.5% NaOCl; 2% chlorhexidine; 0.2% chlorhexidine, EDTA, and citric acid; and 0.5% NaOCl.     

Controlled local delivery of antimicrobials in the treatment of periodontitis

Five local delivery systems with five different antimicrobial agents have been discussed. All are capable of delivering high concentrations of their antimicrobial to the site of the periodontal infection. Although only one system, tetracycline fiber, is available in United States, two other systems, chlorhexidine chip and doxycycline polymer, may be available in the near future. Two other systems, metronidazole gel and minocycline ointment, are available in other countries. Data from pertinent studies were presented as were techniques for using the various systems. Indications for the use of the products were also discussed. In selecting the appropriate delivery system, the clinician has to weigh the efficacy of the products, ease of use, availability, and cost. Although local delivery systems do not replace existing periodontal therapies, they do have a place in the treatment of periodontitis and offer the dentist additional methods to aid in the control of periodontal diseases.     

Randomised trial of 0.2% chlorhexidine gluconate and 2.5% natamycin for fungal keratitis in Bangladesh

AIM: The management of suppurative keratitis due to filamentous fungi presents severe problems in tropical countries. The aim was to demonstrate the efficacy of chlorhexidine 0.2% drops as an inexpensive antimicrobial agent, which could be widely distributed for fungal keratitis. METHODS: Successive patients presenting to the Chittagong Eye Institute and Training Complex with corneal ulcers were admitted to the trial when fungal hyphae had been seen on microscopy. They were randomised to drop treatment with chlorhexidine gluconate 0.2% or the standard local treatment natamycin 2.5%. The diameters, depths, and other features of the ulcers were measured and photographed at regular intervals. The outcome measures were healing at 21 days and presence or absence of toxicity. If there was not a favourable response at 5 days, "treatment failure" was recorded and the treatment was changed to one or more of three options, which included econazole 1% in the latter part of the trial. RESULTS: 71 patients were recruited to the trial, of which 35 were randomised to chlorhexidine and 36 to natamycin. One allocated to natamycin grew bacteria and therefore was excluded from the analysis. None of the severe ulcers was fully healed at 21 days of treatment, but three of those allocated to chlorhexidine eventually healed in times up to 60 days. Of the nonsevere ulcers, 66.7% were healed at 21 days with chlorhexidine and 36.0% with natamycin, a relative efficacy (RE) of 1.85 (CL 1.01-3.39, p = 0.04). If those ulcers were excluded where fungi were seen in the scraping but did not grow on culture, the estimated efficacy ratio does not change but becomes less precise because of smaller numbers. Equal numbers of Aspergillus (22) and Fusarium (22) were grown. The Aspergillus were the most resistant to either primary treatment. CONCLUSIONS: Chlorhexidine may have potential as an inexpensive topical agent for fungal keratitis and warrants further assessment as a first line treatment in situations where microbiological facilities and a range of antifungal agents are not available.     

Susceptibility of Chlamydia trachomatis to chlorhexidine gluconate gel

To identify topical antimicrobial preparations which may be effective in preventing the transmission of sexually transmitted diseases, we examined the activity of chlorhexidine gluconate (CHG) against Chlamydia trachomatis. Chlamydial elementary bodies were incubated with dilutions of CHG gel for various times from 0 to 120 min. An aliquot of each dilution was further diluted and was inoculated onto McCoy cell monolayers in individual wells in a 96-well microtiter plate. The cultures were incubated for 48 h, and the chlamydial inclusions were stained and counted. CHG gel diluted fourfold (0.0625% CHG) killed C. trachomatis serovar D, and CHG gel diluted eightfold (0.0313% CHG) killed serovar F immediately upon exposure. CHG gel diluted 16-fold (0.0156% CHG) killed serovar D, and CHG gel diluted 32-fold (0.0078% CHG) killed serovar F after 120 min of exposure. Alteration of the pH over the range of from 4 to 8 did not significantly affect its activity. The addition of 10% whole human blood decreased the CHG gel activity at 0 min but had no significant effect after 120 min of exposure. We conclude that CHG gel may be effective topically against C. trachomatis at concentrations that can be used and under conditions that are found in the female genital tract and that further studies of its antimicrobial efficacy and toxicity in vivo are warranted.     

Fetal echocardiography

From a research programme comparing two photorefractive keratectomy (PRK) methods, Group S using Summit ExciMed UV 200, and Group V using the VisX 20:20 excimer laser system, 10 patients from each group were recruited. They were referred 6-12 months post-PRK for lens fitting to correct resultant ametropia or irregular astigmatism. Ablation zone diameters were: Group S, 4.5 mm; Group V, 4-6 mm. For Group S, best fit rigid gas permeable (RGP) lenses generally had a back optic zone radius (BOZR) 0.10 mm steeper than the mean keratometry reading (K) and overall diameter of 9.20-10.0 mm. For Group V best fit RGP lenses generally had a BOZR of 0.20 mm steeper than the mean K. The lenses often required large diameters to improve lens centration and extra negative power to compensate for the positive power of the central tear pool. Several patients required soft lens fitting to improve comfort and some finally opted for repeat PRK.     

Full- versus partial-mouth disinfection in the treatment of periodontal infections. A pilot study: long-term microbiological observations

A standard periodontal treatment consists of 4 to 6 scalings and rootplanings at a 1- to 2-week interval, which allows reinfection of a previously disinfected area before completion of the treatment. The present pilot study aims to examine the microbiological long-term effects of a full-mouth disinfection. 10 patients with advanced chronic periodontitis were randomly allocated to a test and control group. The patients from the control group received scaling and rootplaning and oral hygiene instructions at a 2-week interval. The full-mouth disinfection (test group) consisted of a full-mouth scaling and rootplaning in 2 visits within 24 h in combination with: tongue brushing with 1% chlorhexidine gel for 1 min, mouth rinsing with 0.2% chlorhexidine solution for 2 min and subgingival irrigation of all pockets (3x in 10 min) with 1% chlorhexidine gel. The patients of the test group were instructed to rinse 2x daily with 0.2% chlorhexidine. Plaque samples were taken at baseline and after 1, 2, 4 and 8 months. Differential phase-contrast microscopy showed a significantly larger reduction of spirochetes and motile organisms in the test group up to month 2 for the single-rooted and up to month 8 for the multi-rooted teeth. Furthermore, the culture data supported the effectiveness of the new treatment strategy. In both groups, the number of anaerobic CFU decreased 1 log around single- and 0.5 log around multi-rooted teeth. The number of anaerobic CFU remained low in the test group, in contrast to the control group. At 1 month, the test group harboured a significantly (p<0.01) lower proportion of pathogenic organisms, but this difference disappeared with time. Moreover, the test sites showed a significantly higher (p<0.02) increase in the proportion of beneficial micro-organisms up to 4 months. These findings suggest that a full-mouth disinfection leads to a significant microbiological improvement up to 2 months, which could be consolidated, although not significant, for the next 6 months.     

Effect of topical anesthetic use on initial patient satisfaction and overall success with rigid gas permeable contact lenses

BACKGROUND: Rigid gas permeable (RGP) contact lenses have numerous benefits; however, RGP lens use is not increasing in the United States. An important factor for this trend has been initial comfort. Studies have demonstrated that how RGPs are presented to patients, in addition to lens design, can play an important role in the initial comfort process. Another important factor could be the use of a topical anesthetic during the fitting and dispensing visits. The purpose of this study was to use a multicenter format to determine if topical anesthetic use increased the likelihood of patient satisfaction and success. METHODS: A total of 80 subjects, with no previous rigid lens wear experience, was entered into this 1-month study, including 20 subjects from each of 4 institutions. Subjects were randomly divided into the following two groups: (A) anesthetic or (B) placebo, with the former group receiving one drop of a topical anesthetic before lens insertion at both the diagnostic fitting and dispensing visits, whereas the latter group received a placebo. Subjects completed a questionnaire on their perception of rigid lens wear both immediately before fitting and at the 1-month visit. After diagnostic fitting with rigid lenses, subjects completed an adaptation questionnaire after 15 min, 1 week, 2 weeks, and 1 month of lens wear. RESULTS: Seventy of the 80 subjects completed the study and, of the 10 subjects who discontinued, 8 were in the placebo group. In all categories evaluated, the anesthetic group experienced a more optimum adaptation experience at each visit vs. the placebo group. Specifically, overall comfort was rated significantly higher at both dispensing and 2 weeks. In addition, the anesthetic group exhibited significantly greater overall satisfaction with rigid lens wear at 2 and 4 weeks. Also, the anesthetic group perceived their adaptation, sensitivity, and adaptation time to be significantly better at the 1-month visit. There was no significant difference in corneal staining between these two groups at each visit, with the exception of a greater amount of staining in the central quadrant for the placebo group at the 1-month visit. CONCLUSIONS: The use of a topical anesthetic at the fitting and dispensing visits for first-time wearers of RGP lenses resulted in significantly fewer dropouts, improved initial comfort, an enhanced perception of the adaptation process, and greater overall satisfaction after 1 month of lens wear as compared to the use of a nonanesthetizing placebo at those visits. This result, in combination with both presenting RGP lenses in a nonthreatening manner and optimizing the lens design and fitting relationship, should result in a positive adaptation process and successful wear of RGP contact lenses.     

Gender differences in psychosocial profile at entry into cardiac rehabilitation

PURPOSE: To assess whether the contact lens to cornea-bearing relationship, as determined from the fluorescein pattern, can be predicted from videokeratography. METHODS: Nineteen non-rigid gas permeable (RGP) lens wearers were each tested for fluorescein patterns with a series of seven RGP contact lenses of different base curves, and compared to a theoretical estimate of the fitting relationship from videokeratography. The experimentally determined alignment lens was then compared to the theoretical alignment (TA) value as determined from the central curvature and eccentricity. RESULTS: The mean difference in lens choice between the TA and experimental alignment (EA) values was -0.01 +/- 0.04 mm and between the simulated keratometric (KA) readings and the EA choice was 0.11 +/- 0.05 mm. CONCLUSION: A knowledge of the eccentricity value from videokeratography allowed a better prediction of the base curve to cornea relationship than was provided by only a central corneal measurement.     

Flavobacterium meningosepticum in the hospital environment

Ten strains of Flavobacterium meningosepticum were isolated from routine clinical material during a period of two years. Of a number of antibiotics tested, clindamycin was the only one to which they were fully sensitive. The organism was found in chlorhexidine gluconate (Hibitane) solutions in use on the wards for the storage of thermometers and for routine disinfection.     

Implications of oral infections on systemic diseases in the institutionalized elderly with a special focus on pneumonia

Systemic infection in the elderly patient living in a chronic care setting presents a significant burden to the health care system. The extent to which oral organisms cause systemic infections through hematogenous dissemination in the institutionalized elderly is still unknown. A more likely and common route of systemic infection by oral microorganisms is through aspiration of oropharyngeal fluids containing oral pathogenic microorganisms, which colonize the lower respiratory tract and cause pneumonia. Respiratory pathogens emerge in the dental plaque of elderly patients with very poor oral hygiene and severe periodontal disease. In the chronic care setting, aspiration of oropharyngeal fluids contaminated with these bacteria occurs in patients with diminished host defenses, resulting in bacterial pneumonia. This is also a problem in intensive care units in the hospital setting. In one study, pre-rinsing with a 0.12% chlorhexidine gluconate mouthwash significantly lowered the mortality rate from postsurgical pneumonia in patients undergoing open heart surgery. Selective digestive decontamination, a technique involving the topical application of antimicrobials to reduce the risk of colonization of the respiratory tract, has been used to reduce the incidence of nosocomial pneumonia in the acute care setting of hospitals. This technique has not been employed in the nursing home setting. Whether improving oral hygiene would also lower the risk in either of these settings has not been studied. A number of obstacles must be overcome in designing studies to investigate the relationship between oral infections and lung infections in the institutionalized elderly. Ethical issues must be addressed, and full collaboration of the medical team is required. Future studies should establish whether reducing the risk for pneumonia in the institutionalized elderly is possible through improved oral health.