Topical therapy for burns

Prevalence of Multidrug-Resistant Organism in ICU Burns Patients at Tertiary Care Hospital

Burns carries a high-risk of mortality and morbidity. This with increased chances of drug-resistant infections makes the management complicated. Hence this study was conducted to find out the prevalence of multidrug-resistant organisms (MDRO) in burns patients admitted to the intensive care unit at a tertiary care hospital. A 2-year retrospective study was conducted where burn patients reporting MDRO were included. Statistical analysis was performed using SPSS version 26 where a P-value < .05 was considered statistically significant. Out of 97 patients, tissue cultures of 65 patients revealed the presence of MDRO in 27 (27.8%) patients. A male predominance (17, 63.0%) was noted with a mean age of 29.0-year-old. Fire burn (15, 55.6%) was reported to be the most common cause of burn with an average of 29.9% of Total Body Surface Area (TBSA) involved. MDR Pseudomonas aeruginosa was the commonest organism reported in 12 (44%) patients. The average length of stay (LOS) was noted to be 11.3 days with a mortality rate of 48.1% (overall, in all MDRO'S infections). Patients who reported MDRO showed a tendency for longer hospitalization with a higher risk of mortality as the TBSA increased. However, in presence of other factors in burns like higher TBSA, inhalation injury and lack of advanced skin substitute these mortality figures, and their association can be debated. Lastly, the implementation of control measures, as basic as hand hygiene, should be partaken to reduce the burden of MDR infections.

Wound healing in second-degree burns in rats treated with silver sulfadiazine: a systematic review and meta-analysis

Objective:

This study aims to assess the wound healing efficacy in second-degree burns in rats treated with 1% silver sulfadiazine (SSD)—a sulfonamide antibiotic.

Method:

This is a systematic literature review and meta-analysis performed according to the PICO (Population, Intervention, Comparison and Outcomes) strategy.

Results:

The review found 100 studies in PubMed, Web of Science and other search engines. Of these, 70 studies were pre-selected after removing duplicates. After independent analysis by two reviewers, only seven studies met the inclusion criteria for meta-analysis. All studies except one showed faster wound closure by the application of silver sulfadiazine ointment. Using a random effects model, healing was faster in SSD-treated groups when compared to the control group on day 21, with a statistically significant mean difference of –2.72 days (95% confidence interval: –4.99, –0.45) between treatment and control groups (p<0.01).

Conclusion:

The results of this meta-analysis revealed that SSD aided in faster healing of second-degree burns.

Characteristics and therapeutic applications of antimicrobial peptides

The demand for novel antimicrobial compounds is rapidly growing due to the phenomenon of antibiotic resistance in bacteria. In response, numerous alternative approaches are being taken including use of polymers, metals, combinatorial approaches, and antimicrobial peptides (AMPs). AMPs are a naturally occurring part of the immune system of all higher organisms and display remarkable broad-spectrum activity and high selectivity for bacterial cells over host cells. However, despite good activity and safety profiles, AMPs have struggled to find success in the clinic. In this review, we outline the fundamental properties of AMPs that make them effective antimicrobials and extend this into three main approaches being used to help AMPs become viable clinical options. These three approaches are the incorporation of non-natural amino acids into the AMP sequence to impart better pharmacological properties, the incorporation of AMPs in hydrogels, and the chemical modification of surfaces with AMPs for device applications. These approaches are being developed to enhance the biocompatibility, stability, and/or bioavailability of AMPs as clinical options.

Nine-Residue Peptide Self-Assembles in the Presence of Silver to Produce a Self-Healing, Cytocompatible, Antimicrobial Hydrogel

Silver compounds have been used extensively for wound healing because of their antimicrobial properties, but high concentrations of silver are toxic to mammalian cells. We designed a peptide that binds silver and releases only small amounts of this ion over time, therefore overcoming the problem of silver toxicity. Silver binding was achieved through incorporation of an unnatural amino acid, 3'-pyridyl alanine (3'-PyA), into the peptide sequence. Upon the addition of silver ions, the peptide adopts a beta-sheet secondary structure and self-assembles into a strong hydrogel as characterized by rheology, circular dichroism, and transmission electron microscopy. We show that the resulting hydrogel kills Escherichia coli and Staphylococcus aureus but is not toxic to fibroblasts and could be used for wound healing. The amount of Ag(I) released by hydrogels into the solution is less than 4% and this low amount of Ag(I) does not change in the pH range 6-8. These studies provide an initial indication for use of the designed hydrogel as injectable, antimicrobial wound dressing.

The Care of Thermally Injured Patients in Operational, Austere, and Mass Casualty Situations

Burn injury affects a half million people in the United States annually. The severe thermal injury can have long-term debilitating effects. The management of burn patients in austere and operational environments is more complex. Mass casualty incidents can result in a large number of patients with multiple traumatic injuries, which often include burn injury. Appropriate triage of casualties is essential. Severely burned patients should be evacuated to a burn center if possible. Airway management and fluid resuscitation of burn patients present unique challenges. Supplies, resources, and expertise to maintain a definitive airway may not be readily available. Airway adjuncts can be helpful but judicious use of resources is warranted in the austere setting. Traditional resuscitation of severe thermal injury is not practical in the austere environment. Oral resuscitation and in rare cases rectal hydration may be utilized until the patient can be transported to a medical facility. Much has been learned about the management of burn and polytraumatized patients after mass casualty incidents such as the September 11, 2001 terror attacks and the Pope Air Force Base disaster. A well-coordinated emergency preparedness plan is essential. The care of burn patients in austere, operational, and mass casualty situations can tax resources and manpower. The care of these patients will require creativity and ingenuity. Burn patients can be difficult to manage under normal circumstances but the care of these patients under the above situations complicates the management severalfold.

A novel silver-containing absorbent wound dressing based on spacer fabric

Silver-containing wound dressing based on spacer fabric promotes exuding wound healing through absorbing exudates, keeping moisture, killing bacteria and reducing silver contacting with wound.

Proteomic analysis of the proteins released from Staphylococcus aureus following exposure to Ag(I)

The silver ion (Ag(I)) has well established antimicrobial properties and is widely used in a variety of anti-bacterial ointments and plasters for the control of wound infections. Wounds are frequently colonised by the bacterium Staphylococcus aureus and the aim of the work presented here was to establish how S. aureus responded following exposure to Ag(I). Exposure of S. aureus to Ag(I) resulted in the release of a range of proteins from cells. Analysis of proteins released revealed a number of proteins associated with the stress response (e.g. alkaline shock protein, methionine sulfoxide reductase), virulence (e.g. signal transduction protein) and metabolism (e.g. lipase, acetate kinase, phosphoglycerate mutase). The release of toxins (e.g. α-hemolysin, bifunctional autolysin, leucocidin F) was decreased. These results indicated that, while silver is a potent antimicrobial agent, exposure of S. aureus to this metal results in the release of a variety of proteins from the cell. Many of the proteins showing increased release were antigenic and would have the potential to induce an inflammatory response at the site of infection and thus delay healing.

Burn wound: How it differs from other wounds?

Management of burn injury has always been the domain of burn specialists. Since ancient time, local and systemic remedies have been advised for burn wound dressing and burn scar prevention. Management of burn wound inflicted by the different physical and chemical agents require different regimes which are poles apart from the regimes used for any of the other traumatic wounds. In extensive burn, because of increased capillary permeability, there is extensive loss of plasma leading to shock while whole blood loss is the cause of shock in other acute wounds. Even though the burn wounds are sterile in the beginning in comparison to most of other wounds, yet, the death in extensive burns is mainly because of wound infection and septicemia, because of the immunocompromised status of the burn patients. Eschar and blister are specific for burn wounds requiring a specific treatment protocol. Antimicrobial creams and other dressing agents used for traumatic wounds are ineffective in deep burns with eschar. The subeschar plane harbours the micro-organisms and many of these agents are not able to penetrate the eschar. Even after complete epithelisation of burn wound, remodelling phase is prolonged. It may take years for scar maturation in burns. This article emphasizes on how the pathophysiology, healing and management of a burn wound is different from that of other wounds.

[Environmental exposure to silver and its health effects]

Silver (Ag) possesses a well-known antibacterial activity and has been used for medical treatment and cosmetics such as wound dressing and deodorant powders. Occupational Safety and Health Administration (OSHA) and Mine Safety and Health Administration (MSHA) proposed that the permissible exposure limit (PEL) for both metallic and most soluble Ag compounds should be 0.01 mg/m3. Argyria and argyrosis are known to be caused by deposition of insoluble Ag in the dermis and cornea/conjunctiva. However, the metabolic behavior and biological roles of Ag have not been well characterized in mammals. Ag can be absorbed into the systemic circulation from drinking water, and also through parenteral routes such as inhalation and dermal exposure. Experimental studies have demonstrated that Ag+ induces and binds to metallothionein I and II (MTs), which are cysteine-rich proteins, in cells. MTs are major cytoplasmic metal binding proteins and thereby reduce cellular damage caused by toxic heavy metals including Ag. Profiles of Ag distribution in MTs and other Ag-binding proteins can be determined using high performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS). This technique directly provides information on the intracellular behavior of Ag, which is important for elucidating the mechanism underlying Ag toxicity. Silver nanoparticles (AgNPs) are also commercially used mainly as antimicrobial agents. Despite the widespread use of AgNPs, relatively few studies have been undertaken to evaluate the health effects of AgNP exposure. In the present paper, we discuss the absorption, toxicodynamics, and metabolism of both Ag and AgNPs in mammals and their health effects.

Exposure of Staphylococcus aureus to silver(I) induces a short term protective response

The Ag(I) ion has well established anti-bacterial and antifungal properties. Exposure of Staphylococcus aureus to MIC(80) AgNO(3) (3 μg/ml) lead to an increase in the activity of superoxide dismutase, glutathione reductase and catalase at 30 min but activity declined by 60 min. In addition, exposure of cells to this metal ion for 1 h lead to increased expression of a number of proteins such as elongation factors Ts, Tu and G, fructose-bisphosphate aldolase and triosephosphate isomerase but their expression declined following 4 h exposure. ATP binding cassette transporter protein and oligoendopeptidase F showed increased expression at 4 h. While Ag(I) is a potent antimicrobial agent this work demonstrates that S. aureus can mount a short-term protective response to exposure to the metal ion but that this is eventually overcome.

Efficacy and tolerability of fitostimoline in two different forms (soaked gauzes and cream) and citrizan gel in the topical treatment of second-degree superficial cutaneous burns

A total of 227 patients (mean age 41.3 years, 52% females) with at least one second-degree superficial cutaneous burn of thermal origin of a smallest transverse diameter ≥20 mm and a largest transverse diameter ≤90 mm were randomised to receive the topical application of aqueous extract of Triticum vulgare (Fitostimoline) in two different forms (soaked gauzes and cream) or catalase of horse origin in form of gel (Citrizan Gel), given up to healing or to a maximum of 20 days. The rate of lesion healing at end of study was significantly higher in patients treated with Fitostimoline (gauzes 97.3%, cream 91.5%) than in those receiving catalase (84.5%). The pooled Fitostimoline groups were also significantly more effective than catalase gel in reducing total symptoms score, pain at medication, pain at rest, and burning at end of study. Both formulations of Fitostimoline and catalase gel were well tolerated in terms of adverse effects in the site of application.

Proinflammatory cytokine production in HaCaT cells treated by eosin: implications for the topical treatment of psoriasis

Psoriasis is a multifactorial skin dermatosis characterized in its classical form by erythematous and hyperkeratotic plaques on extensor surfaces of the body, that in most cases can be managed therapeutically by topical agents. Hyperproliferation and a marked inflammation in both epidermis and dermis are thought to be driven by interaction of activated type-1 T lymphocytes and antigen-presenting cells and keratinocytes that release several proinflammatory and immunomodulating molecules. The aim of this study is to investigate whether tetrabromofluorecin, commonly know as eosin, a classical compound traditionally topically used in psoriasis for its presumed anti-inflammatory activities, is able to modulate the production of TNF-alpha, IL-6 and IL-8 that are recognized as the most active and characterized cytokines in the pathogenesis of this skin disorder. HaCaT cell line was used to verify the effects on epidermal inflammation by eosin at scalar doses after testing the viability of cells. Two different population of cells, one stimulated by IFNgamma and one non-stimulated, were cultivated in presence of tolerable concentrations. The expression and release of IL-6, IL-8, IL-10, and TNF-alpha were analysed by RT-PCR and ELISA, respectively. Our results show that tolerable concentrations of eosin were 0.05%, 0.02%, and 0.01%. The expression and production of TNFalpha, IL-8 and IL-6 were dramatically reduced in presence of eosin 0.05% and 0.02% and the action of eosin was more pronounced on TNF-alpha. In agreement with clinical data, our results show that in presence of tolerable concentrations, eosin seems to influence remarkably the production of three important cytokines involved in the hyperproliferation and inflammatory process, giving a specific explanation of its efficacy and supporting its topical use in the clinical setting.

Bacteriology of the burn wound at the Bai Jerbai Wadia Hospital for children, Mumbai, India-A 13-year study, Part I-Bacteriological profile

AIM

To study which organisms were prevalent in our burn unit and their antibiotic sensitivity pattern in brief.

METHOD

Microbiological data of 1534 patients admitted to the burns unit of the Bai Jerbai Wadia Hospital for Children, Mumbai over a period of 13 years (1994-2006) was reviewed retrospectively. A total of 9333 swabs were cultured and antibiotic sensitivities to the isolated organisms determined. The age group of patients admitted to our facility ranged from one month to 15 years.

RESULT

Klebsiella was the predominant organism in our set-up (33.91%), closely followed by Pseudomonas (31.84%). The antibiotic sensitivities of the isolated organisms are discussed in detail in the text.

CONCLUSION

Every treatment facility has microorganisms unique to it and these change with time. It is therefore of paramount importance to have an in-depth knowledge of the resident organisms and their antibiotic sensitivity pattern so that infection-related morbidity and mortality are improved.

Efficiency of controlled topical delivery of silver sulfadiazine in infected burn wounds

The present study is designed to assess the potential benefits of controlled delivery of silver sulfadiazine from collagen scaffold (SSDM-CS) in infected deep partial thickness burn wounds in which epidermis is lost completely and the entire papillary dermis and most of the recticular layer of the dermis is lost. Infection induced by inoculating 10(7) colony forming units (cfu) of Pseudomonas aeruginosa caused significant increase in wound size (20%) till day 15, which decreased significantly from day 9 by SSDM-CS treatment, showing complete healing by day 27 (control > or = 37 days). Early subsidence of infection (<10(2) cfu, day 9) by SSDM-CS resulted in faster epidermal resurfacing and fibroplasia, whereas heavy microbial load (>10(7) cfu, day 9) in controls caused severe inflammatory cellular infiltration. Persistent infection triggered early expression of proinflammatory cytokines intereukin-6, intereukin 1-beta, and tumor necrosis factor-alpha, lasting until day 9, whereas cytokine level decreased in SSDM-CS-treated group by day 6. Infection exacerbated expression of active matrix metalloproteinases (MMPs)-2 and -9 in controls (day 15), while SSDM-CS positively modulated MMP-2 and -9 with faster decline in their levels (day 12). Inherent nature of the dressing to maintain drug level at equilibrium therapeutic concentration (51.2 microg/mL) for prolonged time (72 h), below systemic toxic limits (20 microg/dL, serum level), accelerated the magnitude and sequence of reparative events.

Topical preparations for the treatment of psoriasis: results of a retrospective study over 15 years

BACKGROUND

Psoriasis requires lifelong treatments that depend on the extent, clinical forms and associated conditions.

OBJECTIVE

To retrospectively analyze which topical treatments were used, their efficacy, and potential advantages and disadvantages.

METHODS

A total of 666 patients admitted for the first time over 15 years who were topically treated were retrospectively reviewed and subdivided using clinical forms and PASI into four groups and four subgroups for the applied treatments. For each treatment the mean PASI was calculated daily: on the first, third and sixth day. An X sample statistical analysis and Mann--Whitney U-test were performed. The hospitalization time and correlation with the response to treatment were analyzed.

RESULTS

A statistically significant response was recorded for every regimen. The best combination was clobetasol propionate plus eosin on alternate days with eosin plus cade oil. The highest score was recorded for the 'en plaques' psoriasis. The average length of treatment was of 7.5 days in the best combination. No statistically significant difference among the groups was recorded with respect to the length of hospitalization and PASI.

CONCLUSION

The statistically significant response for all the topical treatments analyzed and recorded in this study does not exclude a potential benefit due to hospitalization per se.

Effect of silver on burn wound infection control and healing: review of the literature

Silver compounds have been exploited for their medicinal properties for centuries. At present, silver is reemerging as a viable treatment option for infections encountered in burns, open wounds, and chronic ulcers. The gold standard in topical burn treatment is silver sulfadiazine (Ag-SD), a useful antibacterial agent for burn wound treatment. Recent findings, however, indicate that the compound delays the wound-healing process and that silver may have serious cytotoxic activity on various host cells. The present review aims at examining all available evidence about effects, often contradictory, of silver on wound infection control and on wound healing trying to determine the practical therapeutic balance between antimicrobial activity and cellular toxicity. The ultimate goal remains the choice of a product with a superior profile of infection control over host cell cytotoxicity.

Bacterial resistance to silver in wound care

Ionic silver exhibits antimicrobial activity against a broad range of micro-organisms. As a consequence, silver is included in many commercially available healthcare products. The use of silver is increasing rapidly in the field of wound care, and a wide variety of silver-containing dressings are now commonplace (e.g. Hydrofiber dressing, polyurethane foams and gauzes). However, concerns associated with the overuse of silver and the consequent emergence of bacterial resistance are being raised. The current understanding of the biochemical and molecular basis behind silver resistance has been documented since 1998. Despite the sporadic evidence of bacterial resistance to silver, there have been very few studies undertaken and documented to ascertain its prevalence. The risks of antibacterial resistance developing from the use of biocides may well have been overstated. It is proposed that hygiene should be emphasized and targeted towards those applications that have demonstrable benefits in wound care. It is the purpose of this review to assess the likelihood of widespread resistance to silver and the potential for silver to induce cross-resistance to antibiotics, in light of its increasing usage within the healthcare setting.

Management of burn injuries in the horse

Extensive thermal injuries in horses can be difficult to manage. The large surface of the burn dramatically increases the potential for loss of fluids,electrolytes, and calories. Burns are classified by the depth of injury: first-degree burns involve only the most superficial layers of the epidermis;second-degree burns involve the entire epidermis and can be superficial or deep; third-degree burns are characterized by loss of the epidermal and dermal components; and fourth-degree burns involve all the skin and underlying muscle, bone, and ligaments. Burns cause local and systemic effects. Routine use of systemic antibiotics is not recommended in burn patients. Topical medications should be water based, be easily applied and removed, not interfere with wound healing, and be readily excreted or metabolized. Weight loss of 10% to 15% during the course of illness is indicative of inadequate nutritional intake. Gradually increasing the grain,adding fat in the form of vegetable oil, and offering free-choice alfalfa hay increase caloric intake.

State of the Art in Burn Treatment

Optimal treatment of burn victims requires deep understanding of the profound pathophysiological changes occurring locally and systemically after injury. Accurate estimation of burn size and depth, as well as early resuscitation, is essential. Good burn care includes also cleansing, debridement, and prevention of sepsis. Wound healing, is of major importance to the survival and clinical outcome of burn patients. An ideal therapy would not only promote rapid healing but would also act as an antiscarring therapy. The present article is a literature review of the most up-to-date modalities applied to burn treatment without overlooking the numerous controversies that still persist.

An in vitro study of the anti-microbial efficacy of a 1% silver sulphadiazine and 0.2% chlorhexidine digluconate cream, 1% silver sulphadiazine cream and a silver coated dressing

Burn sepsis is a leading cause of mortality and morbidity in patients with major burns. The use of topical anti-microbial agents has helped improve the survival in these patients. There are a number of anti-microbials available, one of which, Silvazine (1% silver sulphadiazine (SSD) and 0.2% chlorhexidine digluconate), is used only in Australasia. No study, in vitro or clinical, had compared Silvazine with the new dressing Acticoat. This study compared the anti-microbial activity of Silvazine, Acticoat and 1% silver sulphadiazine (Flamazine) against eight common burn wound pathogens.

METHODS

Each organism was prepared as a suspension. A 10 microl inoculum of the chosen bacterial isolate (representing approximately between 10(4) and 10(5) total bacteria) was added to each of four vials, followed by samples of each dressing and a control. The broths were then incubated and 10 microl loops removed at specified intervals and transferred onto Horse Blood Agar. These plates were then incubated for 18 hours and a colony count was performed.

RESULTS

The data demonstrates that the combination of 1% SSD and 0.2% chlorhexidine digluconate (Silvazine) results in the most effective killing of all bacteria. SSD and Acticoat had similar efficacies against a number of isolates, but Acticoat seemed only bacteriostatic against E. faecalis and methicillin-resistant Staphylococcus aureus. Viable quantities of Enterobacter cloacae and Proteus mirabilis remained at 24h.

CONCLUSION

The combination of 1% SSD and 0.2% chlorhexidine digluconate (Silvazine) is a more effective anti-microbial against a number of burn wound pathogens in this in vitro study. A clinical study of its in vivo anti-microbial efficacy is required.

Subeschar clysis in deep burns

Six hundred thirteen patients with deep burn of up to 50% total body surface area (TBSA) were treated with 0.25% povidone iodine subeschar clysis (PVP-SEC) in addition to surface application of povidone iodine + Neosporin in the form of "crust". The results were compared with those of 595 age, sex and percentage of burn, matched patients treated only by "crust application". The quantitative bacterial count showed significantly less incidence of infection on the 7th and 8th days post treatment (P<0.001). The organisms identified were predominately Staphylcocous aureus and Pseudomonas aeroginosa. Significantly more number of patients, with burns up to 50% TBSA, could be grafted within 20 days in the SEC group. The graft acceptance rate in this group was 90%.

Bacterial silver resistance: molecular biology and uses and misuses of silver compounds

Resistance to silver compounds as determined by bacterial plasmids and genes has been defined by molecular genetics. Silver resistance conferred by the Salmonella plasmid pMGH100 involves nine genes in three transcription units. A sensor/responder (SilRS) two-component transcriptional regulatory system governs synthesis of a periplasmic Ag(I)-binding protein (SilE) and two efflux pumps (a P-type ATPase (SilP) plus a three-protein chemiosmotic RND Ag(I)/H+ exchange system (SilCBA)). The same genes were identified on five of 19 additional IncH incompatibility class plasmids but thus far not on other plasmids. Of 70 random enteric isolates from a local hospital, isolates from catheters and other Ag-exposed sites, and total genomes of enteric bacteria, 10 have recognizable sil genes. The centrally located six genes are found and functional in the chromosome of Escherichia coli K-12, and also occur on the genome of E. coli O157:H7. The use of molecular epidemiological tools will establish the range and diversity of such resistance systems in clinical and non-clinical sources. Silver compounds are used widely as effective antimicrobial agents to combat pathogens (bacteria, viruses and eukaryotic microorganisms) in the clinic and for public health hygiene. Silver cations (Ag+) are microcidal at low concentrations and used to treat burns, wounds and ulcers. Ag is used to coat catheters to retard microbial biofilm development. Ag is used in hygiene products including face creams, "alternative medicine" health supplements, supermarket products for washing vegetables, and water filtration cartridges. Ag is generally without adverse effects for humans, and argyria (irreversible discoloration of the skin resulting from subepithelial silver deposits) is rare and mostly of cosmetic concern.

Silver-sulfadiazine eschar pigmentation mimics invasive wound infection: a case report

A 3-year-old girl with 52% TBSA scalds, mostly partial thickness, was treated topically with 5% mafenide acetate solution and 1% silver sulfadiazine cream. All blood cultures and wound swabs were negative for the first 5 days. On day 6 gram-negative bacteria and yeast forms were isolated from her wounds. High fever and leukocytosis were present and the child was treated with intravenous ampicillin and gentamicin according to sensitivity bacteriogram. The bacteria were identified as Pseudomonas aeruginosa and the yeast was Candida tropicalis. On day 7, Escherichia coli was identified in blood cultures and intravenous cefixime was added. Amphotericin B was added on day 9 when blood cultures grew Candida tropicalis and Burkholderia cepacia. On day 13 dark pigmentation foci developed on some areas of partial-thickness burns in the back, resembling invasive wound infection. White blood cell count was 14,300 cells/mm3, and her body temperature reached 39.7 degrees C. Cultures from the pigmented areas were negative, and biopsies revealed deposits of silver. Most of the areas healed uneventfully, and only about 8% TBSA needed grafting, including some of the pigmented areas. No residual pigmentation remained on discharge.

Colonization of burn wounds in Ain Shams University Burn Unit

A prospective study was carried out on 70 burned patients admitted to the Burn Unit, Ain Shams University Hospital, Cairo, with the aim to verify the pattern of microbial colonization of burn wounds. Throughout the study period starting from 1 June 1999 till 31 May 2001, 281 sampling procedures (surface swabs) were performed from the burn wounds. A total of 301 microbial isolates were grown in cultures. Eight different species of bacteria, and only one species of Candida (C. albicans) were detected. There was no incidence of recovery of anaerobic microorganisms. Our results revealed that the most frequent isolate was Pseudomonas aeruginosa (21.6%), followed by Klebsiella pneumoniae (15.2%), then Escherichia coli (13.6%), Staphylococcus aureus (13.2%), coagulase-negative Staphylococci (11.6%), Streptococcus pyogenes (8.3%), Enterobacter species (6.6%), and lastly Streptococcus faecalis and Candida albicans (5.9 and 3.6%, respectively). Studying the time-related changes in burn wound microbial colonization showed an initial predominance of gram-positive cocci upon admission (70.7%) over gram-negative bacilli (27.6%). During the first 5 days, gram-negative bacilli started to predominate (55.7%) over gram-positive cocci (40.3%). Burn wound sampling performed starting from the sixth day onwards, revealed further prevalence of gram-negative bacilli (72.7%) over gram-positive cocci (22.7%). As for Candida albicans, there was a gradual increase in the frequency of its recovery as time elapsed from admission. It is crucial for every burn institution to determine the specific pattern of burn wound microbial colonization, the time-related changes in the dominant flora, and the antimicrobial sensitivity profiles. This would enable early treatment of imminent septic episodes with proper empirical systemic antibiotics, without waiting for culture results, thus improving the overall infection-related morbidity and mortality.

Comparison of silver sulfadiazine 1%, mupirocin 2%, and fusidic acid 2% for topical antibacterial effect in methicillin-resistant staphylococci-infected, full-skin thickness rat burn wounds

Silver sulfadiazine 1%, mupirocin 2%, and fusidic acid 2% were compared to assess the antibacterial effect of a once-daily application on experimental rat 15% full-skin thickness burn wounds seeded 24 hours earlier with a 10 standard strain of methicillin-resistant staphylococci. The quantitative counts of seeded organism in burn eschar and subjacent muscle were determined at postburn day 7, beside the cultures of blood and lung biopsies. All tested topical agents were equally effective against methicillin-resistant in reducing local burn wound bacterial count and preventing systemic infection.

Septicaemia after burn injury: a comparative study

Seventy-nine (8.4%) patients during June 1992-May 1996 (Group-1) and 68 (7.2%) patients from June 1996 to May 2000 (Group-2) who developed septicaemia at the burns unit of Al-Babtain Centre for Plastic Surgery and Burns, Kuwait, were retrospectively studied and compared. The mean age of 26 years, male predominance, flame burns as main aetiology and mean burn percentage of >or=40% was observed in both the groups. Both groups revealed extensive flame burn, inhalation injury, intubation and difficult resuscitation as the risk factors. The proportion of satisfactory resuscitation increased significantly (P<0.001) in Group-2. The septicaemia commonly occurred within 2 weeks postburn but the number of episodes during 5 days postburn was less in Group-2. The surface wound was found to be the likely source of entry of the organisms into the blood stream in both the groups. The gram positive organisms were dominant aetiologic factor in both groups but an increase frequency of Acnetobacter was found in Group-2. The proportion of MRSE and Pseudomonas septicaemia was significantly higher (P<0.01) in the Group-1. The rate of survivors, in both the groups was higher among operated patients but it was significantly higher (P<0.001) in the Group-1. A mortality rate 20.6% in Group-2 decreased against Group-1, which can be attributed to better resuscitation, nutritional care, early detection of septicaemia, appropriate antibiotics and early wound excision and skin grafting. MOF was the cause of death of 60.9% in Group-1 and 85.7% in Group-2. There was no role of prophylactic antibiotic in burn patients in the incidence of septicaemia and mortality.

Rapid control of wound infections by targeted photodynamic therapy monitored by in vivo bioluminescence imaging

The worldwide rise in antibiotic resistance necessitates the development of novel antimicrobial strategies. In this study we report on the first use of a photochemical approach to destroy bacteria infecting a wound in an animal model. Following topical application, a targeted polycationic photosensitizer conjugate between poly-L-lysine and chlorin(e6) penetrated the gram (-) outer bacterial membrane, and subsequent activation with 660 nm laser light rapidly killed Escherichia coli infecting excisional wounds in mice. To facilitate real-time monitoring of infection, we used bacteria that expressed the lux operon from Photorhabdus luminescens; these cells emitted a bioluminescent signal that allowed the infection to be rapidly quantified, using a low-light imaging system. There was a light-dose dependent loss of luminescence in the wound treated with conjugate and light, not seen in untreated wounds. Treated wounds healed as well as control wounds, showing that the photodynamic treatment did not damage the host tissue. Our study points to the possible use of this methodology in the rapid control of wounds and other localized infections.

The use of silver coated dressings on donor site wounds: a prospective, controlled matched pair study

Acticoat, a new silver-coated dressing, produces a moist healing environment along with the sustained release of ionic silver for improved microbial control. These properties suggest that Acticoat might be a useful donor site dressing. However, there are no human studies which assess Acticoat for this use. The purpose of this study was to compare the healing of human skin graft donor sites dressed with Acticoat, to the healing of those dressed with Allevyn, an occlusive moist-healing environment material, which is our standard donor site dressing. In burn patients who had undergone burn excision and grafting, identical side-by-side split thickness donor site wound pairs were dressed with Allevyn and Acticoat. Re-epithelialization was directly assessed daily by a single observer from post-operative day 6 onward, and by four independent observers who rated the extent of re-epithelialization by viewing standardized digital images of the wounds that had been obtained on post-operative days 6, 8, 10,and 12. Donor sites were swabbed for bacterial culture on days 3, 6, and 9. Subsequently, each study donor site scar was rated by a blinded observer using the Vancouver Scar Scale at 1, 2, and 3 months. Sixteen paired sites in 15 patients (3 female, 12 male) were studied. Donor sites dressed with Allevyn were >90% re-epithelialized at a mean of 9.1+/-1.6 days while donor sites dressed with Acticoat required a mean of 14.5+/-6.7 days to achieve >90% re-epithelialization (P=0.004). The Allevyn sites had significantly greater estimated re-epithelialization at days 6, 8, 10 and 12 than the Acticoat sites based on the observations of the digital images. There were no significant differences in the incidence of positive bacterial cultures with either dressing at days 3, 6, and 9. Donor sites dressed with Acticoat had significantly worse scars at 1 and 2 months but this difference resolved by 3 months. Our findings do not support the use of Acticoat as a skin graft donor site dressing.

An open study comparing topical silver sulfadiazine and topical silver sulfadiazine-cerium nitrate in the treatment of moderate and severe burns

Sixty patients with moderate and severe burns were randomly assigned to receive topical silver sulfadiazine (SSD) alone (n=30) or SSD combined with cerium nitrate (SSD-CN) (n=30). There were four deaths in the SSD group and one in the SSD-CN group; more patients with higher risk severity survived in the SSD-CN group. Wound infection did not differ significantly between the groups. The rate of re-epithelialization of partial thickness burns was faster by 8 days in the SSD-CN group. The relatively dry shell-like eschar of the SSD-CN-treated burn allowed planned excisions with immediate autologous grafting and the tissue beneath was ready to accept grafting 11 days earlier than in the SSD group (p=0.03). This resulted in a significantly shorter hospital stay for those in the SSD-CN group than in the SSD group (23.3 vs. 30.7 days; p=0.03) with consequent cost savings. A higher incidence of transient stinging pain was reported with application of SSD-CN, but this was effectively managed with analgesics where necessary. The results of this study confirm the greater efficacy of SSD-CN in the treatment of burns patients.

Bacteriology in burn patients undergoing mechanical ventilation

In this paper the authors introduce a retrospective study of the incidence of infectious processes in the Burns Unit of the Cruces Hospital (Bilbao), in those patients treated between 1995 and 1998, and who needed, for different reasons, mechanical ventilatory support. The most common microorganisms found in wound cultures, plugged telescoping catheter and blood cultures and analyse variations throughout the stay in the Burns Unit are described.

Nosocomial infections in an Iranian burn care center

Burn patients are obviously at high risk for nosocomial infections due to the immunocompromizing effects of burn injury. Pseudomonas aeruginosa is an important life-threatening nosocomial pathogen in burn units. The aim of this study was to determine nosocomial infections in the Tohid Burn Center in Tehran, Iran. Materials of this study were samples of burn wounds and blood from 582 patients who required hospitalization during March 1996 and September 1998. Burn wound samples were taken on admission day, 3 and 7 days after admission. Frequency of culture positive on admission day, 3 and 7 days after admission were 15, 66, and 88%, respectively. Frequency of P. aeruginosa and Staphylococcus aureus on admission day were 35 and 34%, on the third day after admission 73 and 15%, and at the end of the first week of admission 87 and 9%, respectively. Frequency of blood culture positive was 36% (19/53) of which 89% were P. aeruginosa. Overall mortality rate was 18.5% (108/582). Of these patients, frequency of positive wound culture was 92% (99/108). In conclusion, our results show that P. aeruginosa is the leading cause of nosocomial infections in our burn center. It is also necessary to introduce urgent measures for restriction of the spread of P. aeruginosa infections in our burn center.

Topical antibacterial agents

Topical antibacterial agents occupy an important niche of antimicrobial therapy for both inpatients and outpatients. These agents, including antiseptic and antibiotic preparations, are used for prophylaxis and treatment of infection. Prophylactic uses include application for traumatic and surgical wounds, burns, intravascular catheters, and eradication of S. aureus nasal carriage. Topical antibacterial agents are also used for treatment of primary and secondary pyodermas. Individual antibacterial agents have been reviewed. Of note, despite the widespread use of topical antibacterial agents, further data on which to guide therapy are needed in many instances.

Incidence of postoperative infection or positive culture after facial laser resurfacing: a pilot study, a case report, and a proposal for a rational approach to antibiotic prophylaxis

BACKGROUND

Laser skin resurfacing (LSR) has emerged as a popular procedure for facial rejuvenation; however, there are no clear guidelines regarding systemic antibiotic prophylaxis.

OBJECTIVE

We attempt to provide practical guidelines for antibiotic prophylaxis in LSR based on our experiences, pharmacology, and a review of the literature.

METHODS

In a pilot study, four consecutive full-face LSR patients were treated without oral or topical antibiotics. The next four patients received oral prophylaxis with a narrow spectrum antibiotic. We also report the case of a severe gram-negative infection after LSR.

RESULTS

For full-face LSR, 2 of 4 consecutive patients without antibiotic prophylaxis experienced focal Staphylococcus aureus infection. The next 4 consecutive patients, who had received gram-positive oral prophylaxis, were all culture negative after 2 days. All test sites (5 of 5) were culture negative despite the absence of systemic or topical antibiotics. One patient not in the pilot study receiving gram-positive antibiotic prophylaxis experienced a gram-negative infection.

CONCLUSION

We recommend narrow-spectrum gram-positive oral antibiotic coverage for full-face and regional LSR.

Burn septicaemia: an analysis of 79 patients

Out of 943 patients treated from June 92 to May 96 at the burns unit of the Al-Babtain Centre for Plastic Surgery and Burns, Kuwait, 280 (30%) required admission to the burns intensive care unit (ICBU) and were studied retrospectively. Seventy-nine (28.2%) developed clinically and microbiologically proven septicaemia. Forty-four (56%) were males, 35 (44%) females with a mean age of 26 years (range 45 days to 75 years) and mean total body surface area burn (TBSA) of 46% (range 10-90%). Sixty-two had flame burns, 16 a scald and one had an electric burn. These 79 patients had a total of 118 septicaemic episodes. Sixty (76%) had only one and 19 (24%) had multiple episodes of septicaemia. Fifty-four (68%) had their first episode within 2weeks, though the maximum number of episodes was between 6 and 10 days postburn. Septicaemia was also observed in 13% of patients within 3 days postburn. Out of the 118 episodes, 48 were due to methicillin resistant Staphylococcus aureus (MRSA), 17 due to methicillin resistant Staphylococcus epidemidis (MRSE), 15 to Pseudomonas, 12 to Acinetobacter, four to Streptococcus, another four to Enterococci, two to Klebsiella, one due to Serratia and 15 to more than one organism. Once the septicaemia was diagnosed appropriate therapy was instituted. Fifty-six (71%) patients had 143 sessions of skin grafting and the mortality was low in operated patients. Twenty-three (29.1%) patients died. The low mortality rate was probably due to factors such as continuous clinical and microbiological surveillance leading to quick detection of aetiology, appropriate antibiotic therapy, care for nutrition and early wound cover. This study suggests that flame burn patients are more vulnerable to sepsis. Onset of septicaemia may be as early as 3 days and commonly within 2 weeks. A surface wound is the likely source of entry to the blood stream. Gram positive organisms are dominant in the aetiology. Early detection and appropriate treatment including wound coverage result in a better outcome.

A prospective randomised clinical and histological study of superficial burn wound healing with honey and silver sulfadiazine

Histological and clinical studies of wound healing have been made on comparable fresh partial thickness burns with honey dressing or silver sulfadiazine (SSD) in two groups of 25 randomly allocated patients. Of the wounds treated with honey 84 per cent showed satisfactory epithelialization by the 7th day, and in 100 per cent of the patients by the 21st day. In wounds treated with silver sulfadiazine, epithelialization occurred by the 7th day in 72 per cent of the patients and in 84 per cent of patients by 21 days. Histological evidence of reparative activity was seen in 80 per cent of wounds treated with the honey dressing by the 7th day with minimal inflammation. Fifty two per cent of the silver sulfadiazine treated wounds showed reparative activity with inflammatory changes by the 7th day. Reparative activity reached 100 per cent by 21 days with the honey dressing and 84 per cent with SSD. Thus in honey dressed wounds, early subsidence of acute inflammatory changes, better control of infection and quicker wound healing was observed while in the SSD treated wounds sustained inflammatory reaction was noted even on epithelialization.

The use of porphyrins for eradication of Staphylococcus aureus in burn wound infections

The assessment of deuteroporphyrin-hemin complex as an agent for the treatment of burn wounds infected with a multiple-drug resistant strain of Staphylococcus aureus was performed. The effect of the porphyrin on the survival of the infectious bacteria was first assayed in culture, and later tested as well in a burned infected animal model. The addition of deuteroporphyrin and hemin, separately or together (as a complex) to a growing culture of S. aureus was monitored during 8 hours. It was found that deuteroporphyrin alone was strongly bactericidal only after photosensitization. On the other hand, hemin alone was moderately bactericidal but light independent. A combination of both deuteroporphyrin and hemin was extremely potent even in the dark and did not require illumination to eradicate the bacteria. The in vivo experiments by application of the above porphyrins in combination to infected burn wounds in guinea pigs was an effective way to reduce dramatically the contaminating S. aureus. Reduction of more than 99% of the viable bacteria was noted after the porphyrin mixture was dropped on the eschar or injected into the eschar, an effect that lasted for up to 24 hours. The deuteroporphyrin-hemin complex may be suggested as a new bactericidal treatment of S. aureus infected burns since it was found to be a potent and promising anti-Staphylococcal agent.

Povidone iodine plus neosporin in superficial burns--a continuing study

A total of 1053 patients with superficial burn injury were treated with povidone iodine plus neosporin (PVP + N) and the results after treatment were compared with those obtained after treating 1089 patients with silver sulphadiazine (SSD). Qualitative analysis showed Staphylococcus aureus and Pseudomonas spp. to be the most common infecting organisms. Quantitatively, fewer patients showed infection on the 7th and 18th day post-treatment in the PVP + N group (P < 0.01 and P < 0.001, respectively). Similarly, healing times were also better with PVP + N, with a maximum number of patients having healed within 15 days (P < 0.001). However, the mortality rates were not much different between the two groups.