Comparative frequency of patch test reactions to topical antibiotics

BACKGROUND

Neomycin, clioquinol and fusidic acid are all topical antibiotics widely used in dermatological practice in the U.K., either as a single agent or in combination with topical corticosteroids. However, an adverse effect of topical antibiotics is contact sensitization.

OBJECTIVES

To examine the frequency of positive patch test reactions to fusidic acid, clioquinol and neomycin.

METHODS

To compare the frequency of allergic patch test reactions over 1 year, we patch tested all patients attending the St John's Institute of Dermatology contact dermatitis clinic for one calendar year with fusidic acid, neomycin and clioquinol.

RESULTS

We patch tested 1119 patients. Positive patch test reactions to neomycin were noted in 40 patients (3.6%), compared with eight patients (0.7%) to clioquinol and three patients (0.3%) to fusidic acid. The frequency of medicament allergy to neomycin was thus five times more common than to clioquinol and ten times more common than to fusidic acid. Although fusidic acid is not part of our extended standard series, it is in our medicaments series. Therefore, in the second part of our study, we reviewed all cases of positive patch test reactions to fusidic acid over the last 20 years. We found that the frequency of hypersensitivity has decreased since the early 1980s despite increasing usage; the current average frequency being 1.62 patch-tested patients per year (1.45%) of those patch tested to the medicaments series). The most common diagnosis in such patients was stasis dermatitis (54.2%).

CONCLUSIONS

The frequency of fusidic acid allergy in an eczema population is low and is comparable with published data from over 10 years ago.

Growth and health of Holstein calves fed milk replacers supplemented with antibiotics or Enteroguard

Forty-five Holstein calves were fed milk replacers containing either antibiotics [MRA (oxytetracycline at 138 mg/kg and neomycin at 276 mg/kg), n = 22)] or Enteroguard [MRE, a blend of fructooligosaccharides, allicin, and gut-active microbes at (129 mg/kg, n = 23)] from birth to 5 wk of age to compare effects on average daily gain and on incidence of scours. Performance was evaluated by measuring weight gain, feed efficiency, and fecal scores. The overall body weight gains and severity of scours were not different between treatments, nor were there differences in starter intake or mean body weight gain. During wk 2, the average gain of calves fed MRA was less than that of calves fed MRE (0.07 vs. 0.09 kg/d, P = 0.09), and greater during wk 5 (0.62 vs. 0.51 kg/d, P < 0.01); however, total gain for calves fed MRE was not different from calves fed MRA. Likewise, average feed efficiencies (gain/dry matter intake) were not different. Severity of scours, as measured by fecal scores, and concentrations of serum proteins, an indirect measure of immunoglobulins, were similar for calves fed MRA and MRE. The results suggest that antibiotics in milk replacers can be replaced with compounds such as fructooligosaccharides, probiotics, and allicin to obtain similar calf performance.

Topical perioperative antibiotic prophylaxis for minor clean inguinal surgery

BACKGROUND

In minor clean procedures, such as inguinal hernia repair and varicocelectomy, the efficacy of systemic perioperative antibiotic prophylaxis is not well established. To determine the efficacy of topical antibiotic prophylaxis alone in preventing postoperative wound infection in a minor urologic clean procedure, we retrospectively reviewed the medical records of 1,654 patients who had undergone microsurgical varicocelectomy.

STUDY DESIGN

From September 1985 until December 2000, 1,654 men underwent 2,554 microsurgical varicocelectomies (900 bilateral) by a single surgeon (MG). The skin was shaved and then prepped with standard Betadine gel (Purdue Frederick) that was wiped away with 70% ethanol. No systemic antibiotics were used. The wound was irrigated with 1% neomycin at the moment the incision was made, and then every few minutes until the completion of the procedure, which averaged 45 minutes per side. No postoperative antibiotics were used.

RESULTS

No wound infections occurred. No patient developed an adverse reaction to topical application of neomycin. One can conclude that the infection rate in this study is no higher than 0.2% with 95% confidence.

CONCLUSIONS

Our review of a large series of consecutive clean urologic procedures indicates that by combining a skin preparation of Betadine gel and 70% ethanol with perioperative topical neomycin irrigation at the moment of skin incision, the risk of postoperative wound infection when performing microsurgical varicocelectomy can be effectively reduced to less than 0.2%.

No effect of preoperative selective gut decontamination on endotoxemia and cytokine activation during cardiopulmonary bypass: a randomized, placebo-controlled study

BACKGROUND

Cardiopulmonary bypass predisposes the splanchnic region to inadequate perfusion and increases in gut permeability. Related to these changes, circulating endotoxin has been shown to rise during cardiac surgery, and may contribute to cytokine activation, high oxygen consumption, and fever ("postperfusion syndrome"). To a large extent, free endotoxin in the gut is a product of the proliferation of aerobic gram-negative bacteria and may be reduced by nonabsorbable antibiotics.

OBJECTIVE

To evaluate the effect of preoperative selective gut decontamination (SGD) on the incidence of endotoxemia and cytokine activation in patients undergoing open heart surgery.

DESIGN

Prospective, randomized, placebo-controlled double-blind trial.

SETTING

Tertiary-care university teaching hospital.

INTERVENTION

Preoperative administration for 5 to 7 days of oral nonabsorbable antibiotics (polymyxin B and neomycin) vs. placebo. The efficacy of SGD was assessed by culture of rectal swabs.

PATIENTS

Forty-four patients (median age 65 yrs, 29 males) were included in a pilot study to establish the sampling points of perioperative measurements. Seventy-eight consecutive patients (median age 65 yrs, 55 males) were enrolled for the prospective study; of these, 51 were randomly allocated to take SGD (n = 24) or placebo (n = 27); 27 were included in a control group (no medication).

MEASUREMENTS AND RESULTS

SGD but not placebo effectively reduced the number of rectal swabs that grew aerobic gram-negative bacteria (27% vs. 93%, respectively; p < .001). SGD did not affect the occurrence of perioperative endotoxemia, nor did it reduce the tumor necrosis factor-alpha, interleukin-10, or interleukin-6 concentrations (p > .20), as determined before surgery, upon aorta declamping, 30 mins into reperfusion, or 2 hrs after surgery. Also, SGD did not alter the incidence of postoperative fever or clinical outcome measures such as duration of artificial ventilation and intensive care unit and hospital stay.

CONCLUSION

SGD effectively reduces the aerobic gram-negative bowel flora in cardiac surgery patients but fails to affect the incidence of perioperative endotoxemia and cytokine activation during cardiopulmonary bypass and the occurrence of a postperfusion syndrome.

A prospective, single-blind, randomized controlled trial of antiseptic cream for recurrent epistaxis in childhood

Epistaxis is common in children. Trials show antiseptic cream is as effective as cautery, but it is not known whether either is better than no treatment. We wished to know the efficacy of cream in children with recurrent epistaxis. The design was a single-blind, prospective, randomized controlled trial set in the Otolaryngology clinic in a children's hospital. The participants were 103 children referred by their general practitioner for recurrent epistaxis. Excluded were those with suspected tumours, bleeding disorders or allergies to constituents of the cream. Referral letters were randomized to treatment and no treatment groups. Treatment was antiseptic cream to the nose twice daily for 4 weeks, which was prescribed by the general practitioner before clinic attendance. All children were given an appointment for 8 weeks after randomization. The main outcome measures were the proportion of children in each group with no epistaxis in the 4 weeks preceding clinic review. Complete data were available for 88 (85%) of the children. Of the treatment group, 26/47 (55%) had no epistaxis in the 4 weeks before the clinic appointment. Of the controls, 12/41 (29%) had no epistaxis over the 4 weeks. This is a relative risk reduction of 47% for persistent bleeding (95% CI 9-69%) and an absolute risk reduction of 26% (95% CI 12-40%), giving a number needed to treat of 3.8 (95% CI 2.5-8.5). We conclude that antiseptic cream is an effective treatment for recurrent epistaxis in children.

A comparison of cortisporin and ciprofloxacin otic drops as prophylaxis against post-tympanostomy otorrhea

Myringotomy and tube insertion, a common pediatric surgical procedure, is frequently complicated by purulent otorrhea. Many otolaryngologists routinely use topical antibiotics as prophylaxis against post-tympanostomy otorrhea. The aminoglycosides (neomycin sulfate, tobramycin and gentamicin) contained in commonly used topical antibiotics as well as components of the solutions have been shown to be ototoxic in animal studies. Although little reported evidence of ototoxicity in humans exists, sporadic reports of sensorineural hearing loss linked to topical antibiotic use do exist, and the potential for sensorineural hearing loss must be considered. The purpose of this study is to compare the rate of post-tympanostomy otorrhea in a double-blinded randomized trial using either topical Ciprofloxacin, with no reported ototoxicity, or Cortisporin as prophylaxis. One hundred patients (200 ears) between ages 7 months and 11 years with a diagnosis of recurrent otitis media or chronic otitis media undergoing tympanostomy tube insertion were randomized into two equal groups. Three drops of either drop A or B were placed into each ear at the time of tube insertion and then three times daily for 3 days. Patients were examined at 3 weeks and details of otorrhea were obtained. The rate of otorrhea was analyzed using chi-square. The overall rate of otorrhea was 39 ears (19.5%), 17 (17%) ears for the Cortisporin group and 22 (22%) for the Ciprofloxacin group. The difference in rate of otorrhea was not statistically significant (P=0.372, 95% confidence interval equals -6-16%). Our data suggest that topical Cortisporin offers no benefit over Ciprofloxacin for post-operative otorrhea prophylaxis. Therefore we recommend topical quinolone prophylaxis, which should eliminate concerns about ototoxicity, without sacrificing efficacy.

Effects of daily oral administration of rifaximin and neomycin on faecal aerobic flora in rats

The aim of this study was to compare the influence of rifaximin and neomycin on faecal flora in rats. The study was performed on 18 Wistar rats (three groups of six male animals). Group 1 received rifaximin (50 mg kg(-1)/day), group 2, neomycin (50 mg kg(-1)/day) and group 3 was used as control. Drugs were administered orally, once daily for 3 days. Faecal specimens, collected from each rat on day 3, were cultured for the quantitative and qualitative determination of aerobic microorganisms. Rifaximin treatment produced a marked reduction in the number of total aerobic bacteria and Salmonellae; neomycin caused reduction in Salmonellae, but did not cause statistically significant changes in total aerobic bacterial count. The binding of neomycin with faeces could explain this limited activity, which does not correlate with the in vitro susceptibility of the organism affected. These results confirm that rifaximin is suitable for topical treatment to reduce selected bacterial load in the gut intestines.

The phosphoinositide signaling cascade is involved in photoreception in the leech Hirudo medicinalis

The effects of BAPTA, heparin, and neomycin on electrical light responses were studied in the photoreceptors of Hirudo medicinalis. Light activation produces a fast increase in intracellular Ca2+ concentration (Cai) as detected with the fluorescent Ca2+ indicator calcium green-5N. Chelating intracellular calcium by injections of 10 mmol(-1) BAPTA suppresses spontaneous quantum bumps, reduces light sensitivity by more than 2 log(10) units, and substantially increases the latent period of light responses. BAPTA strongly inhibits the plateau phase of responses to long steps of light. Injections of 45-100 mg ml(-1) of heparin act in a similar manner to BAPTA, affecting the latency of the light responses even more. De-N-sulfated heparin, an inactive analog, is almost ineffective at the same concentration compared with heparin. Heparin diminishes the light-induced Cai elevation significantly, whereas de-N-sulfated heparin does not. Intracellular injections of 50-100 mmol l(-1) of the aminoglycoside neomycin, which inhibits phospholipase-C-mediated inositol 1,4,5-trisphosphate formation, acts similar to BAPTA and heparin. Pressure injections of the hydrolysis resistant analog of inositol 1,4,5-trisphosphate, inositol 2,4,5-trisphosphate, strongly depolarize leech photoreceptors and mimic an effect of light adaptation. These results suggest a close similarity between phototransduction mechanisms in leech photoreceptors and existing models for visual transduction in other invertebrate microvillar photoreceptors.

Dietary Vitamin K1 Requirement and Comparison of Biopotency of Different Vitamin K Sources for Young Turkeys

In a preliminary experiment, the inclusion of vitamin K1 (K1) at a dietary level of 0.1 mg/kg was as effective as 1 or 2 mg/kg in reducing plasma prothrombin time (PT). To obtain an estimate of the dietary K1 requirement and to compare the biopotency of different vitamin K sources for poults, three additional experiments were conducted. In Experiment 1, an incomplete factorial arrangement of treatments was used in which five dietary concentrations of K1 (0, 0.1, 0.25, 0.5, or 2.0 mg/kg) were tested and two concentrations of neomycin (0 or 75 mg/L) in drinking water were used in conjunction with 0, 0.1, and 0.5 mg of K1/kg of diet. Thus, we used a total of eight treatments. Each treatment was given to two pens of poults, with eight poults per pen. Prothrombin time and prothrombin concentration (PC) in plasma were not influenced by inclusion of neomycin in drinking water. The K1 requirement was estimated, on the basis of PT and PC, to be 0.099 and 0.13 mg/kg, respectively, in Experiment 1. Dietary K1 concentrations tested in Experiment 2 were 0, 0.08, 0.31, or 0.44 mg/kg. A similar protocol to that of Experiment 1 was used in this experiment. The results of Experiment 2 indicated that the dietary K1 requirement was 0.079 mg, based on the influence of dietary K1 on PT. In Experiment 3, dietary treatments consisted of the equivalent of 0.22, 0.55, or 1.11 microM of menadione equivalent/kg from vitamin K1, menadione dimethypyrimidinol bisulfite (MPB) or menadione nicotinamide bisulfite (MNB), respectively, and a control without supplementation of any vitamin K source. The results of Experiment 3 showed that the biopotency of K1 was greater than that of MPB or MNB. The biopotencies of MPB and MNB were similar, although MNB was more potent in reducing plasma PT when supplemented at the level of 0.1 mg of menadione/kg. A nadir of PT and a plateau of PC were evident with a dietary supplementation of MPB or MNB at a level of 0.25 mg of menadione/kg. Results of this research show that the dietary K1 requirement of young turkeys is in the range of 0.079 to 0.13 mg/kg, and ingestion of neomycin did not affect estimates of the requirement. The biopotency of vitamin K1 in reducing plasma PT and increasing plasma PC was greater than that of MPB or MNB. The biopotency of MNB was greater than that of MPB when menadione supplementation was equivalent to 0.10 mg of K1/kg.

[Selective intestinal bacterial decontamination in experimental acute pancreatitis]

BACKGROUND

Bacterial translocation implies the transit of viable gastric microflora from the intestinal lumen through the intestinal wall to the mesenteric ganglia and seems to be the mechanism by which microflora reach necrotic tissue in acute pancreatitis (AP). This occurs in 40-70% of necrotizing hemorrhagic AP and plays a major role in up to 80% of deaths from this cause.

AIMS

To analyze the possible influence of bacterial decontamination in the gut on bacterial translocation in severe experimental AP.

METHODS

Severe AP was induced in 43 male Sprague-Dawley rats by administration of 0.2 ml of 2.5% taurodeoxycholate sodium in NaOH glycyl-glycine buffer after cannulizing the bilio-pancreatic duct through the duodenum and clamping the common bile duct in the hepatic junction. The rats were divided into two groups: a) control group: 24 rats in which only AP was induced; b) problem group: 19 rats that underwent bacterial decontamination through the administration of 4 mg/ml gentamicin, bacitracin and neomycin in the drinking water during the 5 days prior to AP induction. Twenty-four hours after AP induction, laparotomy was performed and a sample for the culture of mesenteric lymphatic ganglia, pancreas, liver, spleen, peritoneum and cecum was obtained.

RESULTS

Seven rats in the control group died. Of the 17 rats that survived 24 hours, positive cultures in the pancreas were obtained in nine. In the problem group, two rats died within 24 hours. Of the remaining 17 rats, positive pancreatic cultures were obtained in 2 while in 15 pancreatic cultures were negative. No microflora were cultured in the peritoneum. The microflora most frequently cultivated were Escherichia coli, enterococcus and proteus. No differences were found in the percentage of Gram-positive and Gram-negative bacteria between the two groups.

CONCLUSIONS

a) The majority of the bacteria in AP tissue originate in the intestinal microflora, E. coli being the most prevalent. b) One of the main mechanisms in this process is bacterial translocation via the lymphatic pathway; transit directly through the transperitoneal pathway is not essential. c) Bacterial translocation already occurs in the earlier phases of AP. d) Bacterial decontamination prior to AP decreases the frequency of bacterial translocation and does not interfere in the Gram-positive/Gram negative balance, nor does it increase fungal infections.

Patch testing with neomycin sulfate

The recommended patch test concentration of neomycin sulfate is 20% in petrolatum applied occluded for 48 h (2 days [D]). In the current study, the efficiency of such a test is compared to results with other techniques using lower allergen dose than obtained by approximately 20 microl of the 20% substance. Efficiency of petrolatum and demineralized water as vehicles are compared. 16 neomycin-sulfate positive subjects were retested with serial doses ranging from 0.4 to 0.0085 mg/cm2 neomycin sulfate in cellulose printed on polyester squares and applied by both tapes and plastic foils. Additionally, tests were performed with the 20% petrolatum substance in Finn Chambers. Tests containing the 20% substance in petrolatum and in water were applied directly with transparent foils. Readings ranged from 3 to 264 h (11D) following applications. Results show that foil applications of a polyester square dose, that is 7% of the dose obtained with the 20% substance, distinguished between perfusion of subjects who were visually positive and not with any test in the study. With the same test technique and visual assessments, 2 subjects were false-negative but developed doubtful test responses with the Finn Chambers.

Diffuse Lamellar Keratitis Induced by Trauma 6 Months After Laser in situ Keratomileusis

This case report illustrates an unusual presentation of diffuse lamellar keratitis triggered by a foreign body striking the eye 6 months after laser in situ keratomileusis (LASIK). The etiology of diffuse lamellar keratitis is unclear. The infiltrate within the plane of the flap after removal of the foreign body supports the theory that diffuse lamellar keratitis is an inflammatory reaction.

A newly formulated topical triple-antibiotic ointment minimizes scarring

A randomized study of polymyxin B sulfate-bacitracin zinc-neomycin sulfate versus simple gauze-type dressings in dermabrasion wounds assessed the effects that each treatment had on scarring. Each of three uniform dermabrasion wounds created on the upper backs of 70 subjects was treated concurrently with a triple-antibiotic ointment (polymyxin B-bacitracin-neomycin), a double antibiotic (polymyxin B-bacitracin), or a simple, non-occlusive, gauze-type dressing, twice daily for up to 14 days. Pigmentary changes and textural changes (scarring) appearing after healing at the skin surface test sites were compared to adjacent normal skin at 45 and 90 days post-dermabrasion. These changes were graded visually utilizing fluorescent light, long-wave ultraviolet light, and by clinical color photography. The triple-antibiotic ointment was superior to simple gauze-type dressing alone in minimizing the scarring observed in dermabrasion wounds. The benefit of this new ointment was more pronounced in its effect on pigmentary changes.

Tympanostomy tubes and otic suspensions: do they reach the middle ear space?

The treatment of patients with tympanostomy tubes (TTs) and otorrhea with medicated otic suspensions is well known, but confirmation of penetration into the middle ear is difficult. To address this question, we created an in vitro model of the human head and ear and then tested it with 5 different types of liquid exposure: tap water, soapy water, polymyxin B sulfate (Cortisporin), tobramycin and dexamethasone (TobraDex), and ciprofloxacin (Cipro) suspensions. A positive test result corresponded to liquids entering the middle ear through the TT. No positive test result was elicited with tap water (0/20), but soapy water did enter the middle ear (10/40) and was statistically significant (P = 0.0112). Without the use of slight tragal pressure, Cortisporin, TobraDex, and Cipro drops did not consistently pass through the TT (0/20, 1/25, 1/25). By placing the drops with the addition of tragal pressure, a statistically significant difference was obtained for each solution (20/20, 20/20, and 20/20, respectively [P < 0.0001]). We conclude that with a clean external auditory canal, patent TT, and no middle ear fluid, medicated otic suspensions enter the middle ear only when combined with slight tragal pressure.

Efficacy of neomycin sulfate water medication on the control of mortality associated with colibacillosis in growing turkeys

The objective of this investigation was to evaluate the efficacy, safety, and toxicity of neomycin sulfate (Neomix 325) water medication to control mortality associated with colibacillosis (Escherichia coli) in growing turkeys. One efficacy trial was conducted at five locations; each location included 2,880 sexed 21-d-old turkey poults that were naturally challenged with litter from turkey flocks that had colibacillosis. Between 5 and 7 d after challenge, and when mortality had reached 0.5%, poults were randomized within sex into three treatment groups of 0, 11, or 22 mg neomycin sulfate/kg body weight. In each location, each treatment was replicated 12 times with 40 poults per sex per replicate. All treatments were administered in the drinking water for 5 d. The pivotal decision criterion was mortality. Mortality was defined as 1) supported mortality (SM): positive microbial culture for E. coli and gross lesions, 2) diagnosed mortality (DM): diagnosed as associated with E. coli but not supported by lesions or positive microbiological cultures, 3) overall mortality (OM): mortality associated with E. coli or other microorganisms and miscellaneous reasons such as accidents (trampling or suffocations). Performance data (growth and feed utilization) also were measured and are reported without statistical analysis. Results from this efficacy study clearly demonstrated the effectiveness of neomycin sulfate against E. coli as measured by a reduction in mortality. In the target animal safety and toxicity study (done in conjunction with the efficacy study), neomycin sulfate in the drinking water at 66, 110, or 220 mg/kg per d for 15 d had no observable adverse effects on poult performance, as measured by feed or water consumption, body weight, gross pathology, or mortality.

Single ototopical application of mesna has no ototoxic effects on guinea pig cochlear hair cells: a morphological study

Mesna (Mistabron) is a mucolytic substance that is also used for chemically assisted dissection during cholesteatoma surgery. The present animal study aims to evaluate its possible ototoxic side effects. To this end, the right tympanic cavity of 9 guinea pigs was filled with either 20% mesna or 10% neomycin (serving as a positive control), while the left tympanic cavity was filled with saline (serving as a negative control). One week after administration, the inner ears were dissected out and further processed for morphological evaluation by means of either interference contrast microscopy or scanning electron microscopy. No macroscopic signs of middle ear inflammation were observed in any of the ears treated. Whereas damage was obvious in all neomycin-treated specimens, the morphology of both saline- and mesna-treated inner ears was unaffected. These findings led us to conclude that, at least on a morphological basis, no indications are at hand to assume ototoxic effects of this mucolytic substance due to a single application during cholesteatoma surgery.

Possible participation of an islet B-cell calcium-sensing receptor in insulin release

The calcium-sensing receptor gene was recently shown to be expressed in rat pancreatic islets and purified islet B-cells. In this study, we investigated the possible role of this receptor in the regulation of insulin release from isolated rat pancreatic islets. Poly-L-arginine (0.2-0.3 microM) and poly-L-lysine (0.03-0.1 microM) increased insulin output evoked by D-glucose (8.3 mM). This positive effect faded out at higher concentrations of the basic peptides. Likewise, the release of insulin evoked by 8.3 mM D-glucose was significantly lower at high (1.0 mM) than low (0.05-0.1 mM) concentrations of neomycin. The insulinotropic action of Ba2+ in Ca2+-deprived islets was potentiated in rats pretreated with pertussis toxin. However, Gd3+ inhibited insulin release evoked by D-glucose in islets prepared from normal rats or animals pretreated with pertussis toxin and incubated in the absence or presence of either theophylline or forskolin. Gd3+ (0.3 mM) failed to affect effluent radioactivity from islets prelabeled with myo-[2-3H]inositol and cyclic AMP net production in islets incubated in the absence or presence of forskolin. Gd3+ decreased, however, 45Ca efflux from prelabeled islets perifused in the absence or presence of extracellular Ca2+. It is speculated that a negative insulinotropic action mediated by the calcium-sensing receptor, and possibly attributable to a fall in cytosolic Ca2+ concentration, may prevent excessive insulin secretion in pathological situations of hypercalcemia.

[Effects some drugs of re-epithelialization in the early postoperative period after photorefraction keratectomy]

Terms of re-epithelialization, severity of the painful syndrome, intensity of corneal "crepe" (opacity) are assessed in myopic patients treated by maxitrol, eubetal, colbiocin ointments and maxitrol eyedrops in the early postoperative period after photorefraction keratectomy. The crepe intensity was assessed routinely according to a clinical score: 0) transparent cornea, 1) trace crepe; 2) moderate crepe; and 3) intensive crepe. Biomicroscopy on day 4 after photorefraction keratectomy showed complete epithelialization in 91.7% patients after colbiocin ointment, in 91.% after maxitrol eyedrops, 87% after eubetal ointment, and 82.6% after maxitrol ointment. The least corneal opacity (0 and 0-1) was observed after eubetal ointment and maxitrol eyedrops. The mean score for pain was virtually the same in all groups; in the colbiocin ointment group more patients complained of pain for more than 24 h in comparison with other groups.

Fecal excretion pattern of bile acids in rats fed high fat diets and neomycin in induced colon tumorigenesis

Neomycin augments colon tumorigenesis in 1,2 - dimethylhydrazine treated rats fed polyunsaturated fat diet and decreases fecal cholic acid excretion, while it inhibits tumorigenesis with increased cholic acid and decreased deoxycholic acid excretions in rats fed high cholesterol diet. Participation of other fecal bile acids seems to be insignificant in relation to colon carcinogenesis.

A multilocation clinical trial in lactating dairy cows affected with clinical mastitis to compare the efficacy of treatment with intramammary infusions of a lincomycin/neomycin combination with an ampicillin/cloxacillin combination

A study was conducted to compare the efficacy in lactating dairy cows of intramammary infusions in quarters affected with clinical mastitis between a formulation containing 330 mg lincomycin and 100 mg neomycin in a 10-mL aqueous solution (LINCOCIN FORTE S, Pharmacia & Upjohn) and a formulation containing 75 mg ampicillin and 200 mg cloxacillin in an oil suspension (AMPICLOX, Pfizer Animal Health). This study was designed as a multicentre clinical trial involving investigators in France, Germany and Belgium and carried out according to the European Commission guidelines on Good Clinical Practices. Cows in the herds were monitored for clinical mastitis. When evidence of clinical mastitis was detected in a single quarter, a pretherapy milk sample was collected from the affected quarter. After milk sampling, the cow was assigned to one of the two treatment groups at random and treated with an intramammary infusion of one syringe of either LINCOCIN FORTE S or AMPICLOX for three successive milkings in the mastitic quarter. At 4-5, 13-15 and 20-22 days after first infusion, the veterinarian returned to the farm to conduct a clinical examination and collect milk samples from the affected quarter. Milk samples were cultured for the presence of mastitis organisms and somatic cell count (SCC) was measured. Following a 10-month study period, 256 cases were enrolled in the study. A total of 232 and 189 cases were analysed for clinical cure and for clinical-plus-bacteriological cure, respectively. The proportions of cases cured clinically and cured clinically-plus-bacteriologically were compared between the two treatment groups. Somatic cell count differences between treatment groups were also tested. The clinical cure rate for LINCOCIN FORTE S (62.5%) was significantly better than for AMPICLOX (51.8%) (P = 0.035). The clinical-plus-bacteriological cure rate was also significantly better for LINCOCIN FORTE S (38.1%) than for AMPICLOX (21.7%) (P = 0.005). Among bacteriologically cured cases, the SCC declined in both treatment groups but the SCC was significantly higher for the AMPICLOX group than for the LINCOCIN FORTE S group (P = 0.036). In conclusion, clinical cure rate, clinical-plus-bacteriological cure rate, and SCC level were significantly better with LINCOCIN FORTE S than for AMPICLOX.

Assessment of the potential for microbial resistance to topical use of multiple antimicrobial agents

The goal of this study was to reduce the likelihood of the generation and/or persistence of bacterial resistance to some antimicrobial components contained in a topical antimicrobial mixture (neomycin, polymyxin B, mupirocin and ciprofloxacin) for use with cultured skin grafts, by substitution of alternative antimicrobials, specifically fusidic acid for mupirocin and ofloxacin for ciprofloxacin. The alternative agents failed to serve that purpose. However, with the exception of specific genera of bacteria, Proteus sp. and Providencia stuartii, 90% or more of all other bacteria tested were susceptible to the action of one or more of the individual antimicrobial agents contained in the original mixture. This was true when bacteria were highly susceptible to the antimicrobials, generally, or when bacteria resistant to specific antimicrobials such as penicillin-class antibiotics and ciprofloxacin, were tested. These results suggest that the redundancy of antimicrobials contained in this mixture reduces the chance that resistant bacteria generated by the use of this mixture or already present on wounds would persist when the mixture is used clinically.