Analysis of IL-6, IL-10 and IL-17 genetic polymorphisms as risk factors for sepsis development in burned patients.

Infection risk, sepsis and mortality after severe burn are primarily determined by patient age, burn size, and depth. Whether genetic differences contribute to otherwise unexpected variability in outcomes is unknown. We sought to determine whether there was an association between IL-6, IL-10 and IL-17 polymorphisms with cytokine production and development of sepsis. We evaluated 71 patients with burns ≥15% TBSA and 109 healthy subjects. The genotypes of IL-6 (-174C/G), IL-10 (-819C/T and -1082A/G) and IL-17 (7488T/C) polymorphisms were identified applying polymerase chain reaction protocols. The cytokine levels in serum were determined with enzyme-linked immunoabsorbent assays. Our results demonstrated no significant differences in the genotype frequencies studied between burn patients and healthy subjects. No significant associations were found among IL-6 and IL-17F genotypes and the related cytokine serum levels. Only IL-10 promoter -1082GG genotype was related to an increased IL-10 production in burned patients. In addition, septic subjects bearing -1082G/G genotype have shown the highest and non-septic bearing -1082A/* genotypes the lowest IL-10 serum levels. All together these data seem to indicate that genetically determined individual difference in IL-10 production might influence the susceptibility to septic complications in burned patients and suggest that these markers might be useful in burned patient management.

Reduction of plasma granzyme A correlates with severity of sepsis in burn patients.

The risk of mortality is high in burn patients and correlates with age, burn area extent, and sepsis. Immunosuppression has been reported to occur after severe burn. Cytotoxic cells possess specialized granules containing perforin and a group of serine proteases (granzymes). Granzyme A is a serine protease constitutively expressed by gammadelta and NK cells, in agreement with their functional cytolytic potential. In vitro studies have shown that GrA may be released extracellularly during cytotoxic cell degranulation, indicating the activation of cytotoxic cells. The aim of our study was to determine plasma GrA activity in burned patients and to verify if decreased GrA levels were associated with poor prognosis. Specific GrA activity was tested in the plasma of burned and healthy subjects by esterase assay. Plasma GrA was significantly decreased in septic rather than in nonseptic burn patients and in healthy subjects (p < 0.05 and p < 0.001, respectively). At day 3 plasma GrA was significantly lower in nonsurvivor than in survivor septic patients (p < 0.05). The value of 91 mOD showed a sensitivity of 100% and a specificity of 84% in differentiating survivor from nonsurvivor septic patients. Because this is a retrospective study, Granzyme A is not a confirmed predictor of septic outcome after burn, but its determination could give useful information about the development and severity of sepsis.

Circulating dendritic cells following burn.

Burns are associated with immune suppression and subsequent development of sepsis. Dendritic cells (DCs) are potent antigen-presenting cells that serve as a critical link between the innate and acquired immune systems, and are essential in coordinating the host response to pathogens. Using multicolour flow cytometry, the percentages of LIN(-) DR(+) CD11c(+) myeloid (mDC) and LIN(-) DR(+) CD123(+) plasmacytoid (pDC) subsets were determined in peripheral blood from 32 people (15 septic and 5 non-septic burn victims and 12 age- and gender-matched healthy controls, up to 20 days from injury). Analysis revealed significant reductions in circulating mDCs and pDCs in survivor as well as non-survivor septic cases compared with non-septic cases and controls (p<0.001). These findings suggest that deficiencies in mDCs and pDC subsets are related to sepsis following severe burn, and may contribute to immunosuppression among burn victims.

Serum Levels of Cortisol, Immunoglobulin, and C-reactive Protein in Burn Patients.

Thermal injury is known to induce alterations in the immune system, but the precise mechanisms have yet to be elucidated. It has been shown that thermal injury in more than 20% of the total body surface area (TBSA) leads to disturbances in the cortisol metabolism and the equilibrium of the hypothalamic-pituitary-adrenal axis. We investigated the temporal relationship between serum cortisol levels, C-reactive protein, and immunoglobulin levels in the post-burn period. Twenty-one adult burn patients (mean age, 52 ± 17 yrs) were included in the study (TBSA, 10-80%); nine developed sepsis and five died. The nonseptic group consisted of twelve patients. Thirty healthy blood donors served as controls. Our results suggest that increased cortisol and decreased immunoglobulin levels could be related to severe sepsis and clinical outcome.

Skin dendritic cells in burn patients.

The body's immunological response to burn injury has been a subject of great inquiry in recent years. Burn injury disturbs the immune system, resulting in a progressive suppression of the immune response that is thought to contribute to the development of sepsis. Dendritic cells (DCs) are potent antigen-presenting cells that possess the ability to stimulate naïve T cells.DCs are derived from bone marrow progenitors and circulate in the blood as immature precursors prior to migration into peripheral tissues. Within different tissues, DCs differentiate and become active in the taking up and processing of antigens, and their subsequent presentation on the cell surface is linked to major histocompatibility molecules. Upon appropriate stimulation, DCs undergo further maturation and migrate to secondary lymphoid tissues, where they present antigen to T cells and induce an immune response. The purpose of this study was to determine the effects of burn injury on skin DCs in terms of percentage, HLA-DR, and Toll-like receptor-4 (TLR-4) expression. The skin DCs were isolated from burned skin and non-burned skin in the same patient at 7 days post-injury, and skin DCs were isolated from unburned healthy individuals as control. DCs from burned skin notably express low levels of HLA-DR and TLR-4 soon after cell isolation. In the post-burn period the ability of skin DCs to respond to bacterial stimuli is impaired. These changes in DC behaviour might contribute to the impaired host defences against bacteria during burn sepsis.

Local treatment of burns with honeycomb expanded polyurethane (ligasano).

The results are presented of the local treatment of burns with honeycomb expanded polyurethane. This method of treatment can be used both for the medication of burns of limited extent but variable depth and as a mattress for patients confined to bed. In the first case, the purpose of the treatment, which makes use of the product's absorbent and debriding capacity, is either to cure the lesion or to pave the way for the surgical operation. In the second case use is made of the product's exudate-draining and anti-pressure sore activity, which prevents the lesion from becoming deeper.

Concentrations of cytokines IL-6 and IL-10 in plasma of burn patients: their relationship to sepsis and outcome.

Burn injury induces a suppression of the Th1 response, which is associated with an increased susceptibility to conditions of infection, morbidity, and mortality. It is well established that cytokines modulate the pathogenesis of burn injury. In this study, plasma levels of interleukin-6 (IL-6) and interleukin-10 (IL-10) were determined in burn patients and correlated with the severity of sepsis. Sixty adult burn patients (total body surface area burned, 8-80%) were included in the study, of whom 34 developed sepsis and 14 died. The nonseptic group consisted of 26 patients. Thirty-one healthy blood donors served as controls. Patients were not treated with antibiotics until sepsis occurred. Plasma samples were collected immediately post-burn and after several days, and cytokine concentrations were determined by ELISA. Within three days, all the patients presented high levels of circulating IL-6, which were significantly higher in septic patients than in nonseptic patients (349 ± 278 vs 63 ± 56 pg/ml, p < 0.001).IL-10 levels were higher in septic patients than in nonseptic patients at all times in our study. The value of 60 pg/ml shows a sensitivity of 92% and a specificity of 93% in the differentiation of survivor from nonsurvivor septic patients. In this study the high value of circulating IL-10 on day 3 suggests that cytokine may discriminate between nonsurvivor septic and survivor septic patients.

The Treatment of Lyell'S Syndrome: our Experience.

In view of the pathogenic mechanisms of Lyell's syndrome, we consider support-only treatment to be insufficient and believe it is necessary to administer i.v. human immunoglobulin. Because of the potentially severe side effects of the high doses usually recommended, we prefer to use low doses (no more than 5 g per day) in association with the administration of fresh frozen plasma, which offers the benefits of the high protein content in the albumin (with its resuscitatory function) and its globulin content (functioning as a specific therapy for Lyell's syndrome). We present the latest cases we have observed and treated using this protocol.

Pyoderma Gangrenosum and Full-Thickness Burns: is there a Problem of Differential Diagnosis?

A case is presented of pyoderma gangrenosum, describing its characteristic features with particular reference to the phenomenon of pathergy, which considerably limits the surgical approach to the disease. After an account of the numerous skin ulcerations that have to be taken into consideration in order to make a differential diagnosis, it is noted that pyoderma gangrenosum can only on rare occasions be confused with a full-thickness granulating burn.

Staphylococcal Scalded Skin Syndrome: Criteria for Differential Diagnosis from Lyell's Syndrome. Two Cases in Adult Patients.

A review of the relative international literature of the last few years is followed by a description of two cases of staphylococcal scalded skin syndrome in adults. As in both cases the initial diagnosis was that of Lyell's syndrome, the main criteria for the differential diagnosis of the two pathologies are considered in order to permit specific and effective treatment.

The local treatment of burns with antibiotics.

After presenting an analysis of the principal antiseptics used for the local treatment of burns, highlighting their toxicity and the limitations of their antibacterial effectiveness, we describe the therapeutic protocol used in our burns centre (where antibacterial treatment consists exclusively of antibiotics for both local and systemic use). We review the data regarding actual and predicted mortality, and mortality due to septicaemia during the years 2000-2003.

Oxidative stress after moderate to extensive burning in humans.

Lipid peroxidation products, lipid antioxidants, and hematologic and blood chemistry changes were evaluated in plasma of patients after acute burning injury involving 10% (n=8), 20% (n=8), and 40% (n=5) of total body surface area (TBSA), 24 h after burning (baseline) up to 30 days after. Markedly increased plasma levels of malondialdehyde (MDA) were observed at baseline in all patients, according to the extent of the injury, then the values declined progressively. However, levels of MDA remained above normal up to 30 days even in less injured patients. On the other hand, the plasma level of conjugated diene lipid hydroperoxides was only slightly higher than control at the baseline, then dropped under the control value in all patients. Cholesterol showed a marked fall at baseline, followed by a rapidly progressive decrease, indicating a massive loss of circulating lipids by the acute thermal injury. Because of such an extensive and rapidly spreading oxidative degradation of lipids, decomposition of conjugated diene hydroperoxides, produced in early stages of the peroxidation process, occurs, so these compounds cannot be a suitable index to value lipid oxidation in burned patients. Aldehydic products of lipid peroxidation act as endotoxins, causing damage to various tissues and organs. Damage to liver and decrease of erythrocyte survival were assessed by increased plasma levels of asparate and alanine transaminases, within 7-15 days after injury, and by a decreased number of red blood cells, which remained under the normal value at 30 days. A marked decrease of lipid antioxidants, beta-carotene, vitamin A and vitamin E was observed at baseline. The level of beta-carotene remained low in all patients at the end of the 30-day observation. A complete recovery of vitamin A did not occur at 30 days post-burn, even in the patients with 10% of burned TBSA. Plasma levels of vitamin E decreased significantly in 1-7 days after burn in all patients, but these levels increased thereafter, with almost total recovery at 30 days. These data show evidence of a marked, long-lasting oxidant/antioxidant imbalance in burned patients, in accordance with the severity of the injury, which is also reflected as systemic oxidant stress.

Increased burn patient survival with once-a-day high dose teicoplanin and netilmicin. An Italian multicenter study.

This is the final report of a large, controlled, multicenter Italian study on immuno- and chemotherapy in adult patients with burns affecting 20 to 95% of total body surface area (mean 35%). The antibiotic treatment of burn patients consisted of topical silver sulfadiazine, short-term antimicrobial chemoprophylaxis with pefloxacin (800 mg i.v. qd) for the first 4 days and polychemotherapy with teicoplanin (800 mg i.v. qd) together with netilmicin (300 mg i.m. qd) in one or more cycles of 5-12 days. At random, half of the patients received thymostimulin, 70 mg i.m. qd for the first month and every other day thereafter. The analysis at completion of 634 valid cases showed that when the results are stratified by means of the Roi risk index, 396 of the 530 patients who contracted wound infection (84%) after chemoprophylaxis were in the first three categories and a mean of 95% survived. Of the remaining 134 patients (Roi index 4-5) only 50% survived. There was no difference in survival of the immunotherapy group in comparison with the parallel group without thymostimulin. The short-term antimicrobial prophylaxis prevented wound infection in only 104 of 634 patients (16%) and they were at low risk (84% Roi index 1). Of the bacterial pathogens involved in septic complications Staphylococcus aureus and Pseudomonas aeruginosa were prevalent (86%): eradication was achieved in 43% of patients and clinical cure or improvement were seen with combination chemotherapy in 64% of all patients, mainly with only one treatment cycle. This value increased to 79% for the 395 protocol-complying patients and went down to 20% in the 135 non-compliers. The total survival of complier and non-complier patients was 447 of the 530 valid patients (84%). The overall mortality of the 634 evaluable patients was 13.1%, ranging from less than 2% to 68%. Burn mortality was directly proportional to the percentage of burned body surface area, to increasing age and other variables of the Roi index, a 50% mortality being associated with a 72.5% total body surface area burned. Normoergic burn patients had a mortality rate of 9.1% versus 35.7% in anergic patients.