[Dialytic therapy in severely burnt patients with acute renal failure]. / Terapia dialitica dell'insufficienza renale acuta nel paziente Grande Ustionato.

BACKGROUND: Appearance of acute renal failure (ARF) in severely burnt patients (GU) is a serious complication. It has a negative prognostic value and almost always develops in the context of multiple organ dysfunction syndrome (MODS) induced by sepsis. Over the last 20 years, according to data available, the mortality rate has been reported to reach about 75%. We have analyzed the initial results obtained in GU patients who were admitted to the Intensive Care Unit of the Burns Center in Turin. METHODS: Out of 105 GU patients admitted between July 1999 and September 2000 (burned surface area (BSA) 23.8%, range 2-95%, mortality rate 13.7%), 7 patients (6.4%) had complications of ARF requiring extracorporeal dialytic therapy (38 HF sessions lasting 4-6 hours, 2 HF + 12 HDF + 1 UF sessions lasting 8-11 hours). RESULTS: Total BSA of 7 GU patients with ARF was 62.5+/-11.3% (mean +/-SEM). Mortality rate was 71.4% which was due to septic shock and MODS. ARF onset was at 28.4+/-8.4 days from admission. Dialytic treatment started at Crs 2.3+/-0.42 mg/dl, and patients were treated for 7.6+/-3.5 days with a weight loss of 1859+/-161 gr/die. Circuit anticoagulation was obtained by minimal amount of heparin (132.2+/-26.5 U/hour) and no hemorrhagic complications were observed. CONCLUSIONS: In GU patients with ARF the dialytic treatment with daily long-lasting convective- diffusive techniques permitted us to achieve a survival and dialytic adequacy similar to those reported with continuous renal replacement therapies; however, mortality rate is high and related to septic shock and MODS.

Activity of GH/IGF-1 axis in burn patients: comparison with normal subjects and patients with GH deficiency.

The aim of this study was to clarify the activity of GH/IGF-1 axis as well as the variations of nutritional parameters following a thermal injury in man. To this goal, in 22 patients with burn [BURN, age (mean+/-SE): 46.5+/-3.4 yr, BMI: 25.0+/-0.8 kg/m2, % burn surface area: 26.0+/-3.0%, ROI score: 0.22+/-0.1] we evaluated IGF-1, IGF binding protein (IGFBP-3), GH, GH binding protein (GHBP), pre-albumin (pre-A), albumin (A) and transferrin (TRA) levels on days 1, 3, 7, 14 and 28 after intensive care unit (ICU) admission. IGF-1, IGFBP-3, GH and GHBP levels were also assayed basally in 29 normal subjects (Ns) (Ns, age: 47.5+/-2.8 yr, BMI: 22.0+/-1.4 kg/m2) and in 34 panhypopituitary patients with severe GH deficiency (GHD, age: 42.7+/-2.5 yr, BMI: 25.6+/-0.8 kg/m2). On ICU day 1, IGF-1 and IGFBP-3 in BURN were higher than those in GHD (p<0.05 for both, respectively) and lower than those in Ns (p<0.05) while GH levels in BURN did not differ from those in Ns and higher than GHD (p<0.01). In BURN, IGF-I and IGFBP-3 levels showed a progressive decline (p<0.05) with nadir on day 14, when they overlapped those in GHD, and then an increase on day 28, though persisting lower than in Ns, while GH levels did not vary during ICU stay. IGF-I levels were associated neither to burn extension nor to ROI score. On ICU day 1 pre-A, A and TRA levels were similar to those in Ns, but underwent a progressive decrease with nadir on day 7 (p<0.001) for pre-A and TRA, and later, on day 14 (p<0.05) for A; pre-A and TRA but not A showed a rebound increase (p<0.01) on day 14, though persistingly lower than in Ns. In conclusion, our present data firstly show the time course variation of IGF-I levels in burn patients as function of nutritional and hormonal variables. It has to be emphasized that in the most critical phase after burn injuries, IGF-1 levels are as low as in hypopituitary patients with severe GHD. The physiological basis which leads to the impairment of this endogenous anabolic drive in this phase is, however, not clear yet.

The role of quality control in a skin bank: tissue viability determination.

New surgical procedures requiring viable skin have increased rapidly over the last few years. The cell viability assessment in allograft skin is a major step forward in burn treatment, since it is well-known that taking is correlated with grafted tissue viability. Various methods, both qualitative and quantitative, are currently used. Although qualitative assays (histomorphology, immunocytochemistry) are routinely performed in our laboratory, there arose a need to set up a standardised quantitative assay in an attempt to obtain a cut-off value so that the skin sample could be determined valid or not for grafting. Therefore, two different tetrazolium salt compounds MTT and WST-1, were compared in order to determine their efficacy in the evaluation of tissue viability. Several experimental conditions were analysed: 1- cellular cultures of keratinocytes and fibroblasts, 2- fresh skin tissue samples, 3- the same specimen tested daily for at least 2 weeks, 4- after cryopreservation and thawing. Viable cells were analysed by the cleavage of tetrazolium salts to formazan by cellular enzymes. The formazan dye produced by metabolically active cells was then quantified by measuring the absorbance of the dye solution at the appropriate wavelength. It was seen that WST-1 is easier to handle, more stable, has a wider linear range, accelerated colour development and is more sensitive than MTT on fresh specimens and cell suspension. However, after 72 hours of storage at 4 degrees C, most of the WST-1 tested specimens no longer gave any absorbance signal, whilst MTT specimens were seen to give a signal for more than two weeks. Moreover, after thawing WST-1 tested samples were almost negative, whilst MTT samples continued to give strong signals. In conclusion, WST-1 assay offers rapid and precise results as to the cell viability of fresh allografts and cell cultures, whilst the MTT method is much more useful in establishing viability after long conservation and cryopreservation. In our clinical experience, allografts transplanted at 72 hr post-harvesting or after cryopreservation showed a mean of take more than of 80%, demonstrating that the MTT system is more reliable for the determination of allograft viability. Studies are ongoing with larger clinical cohorts to establish the precise cut-off value for skin graft validation.

Expression and role of IL-15 in post-burn hypertrophic scars.

Hypertrophic scarring is a skin disorder that occurs after wounding and thermal injury. There is accumulating evidence that immunologic processes such as infiltration of activated T lymphocytes and altered cytokine production may play a role in the formation of hypertrophic scars. Interleukin-15, a cytokine identified as a T cell growth factor, also acts as a chemoattractant for T cells and has pro-inflammatory properties. We investigated the expression and the role of this cytokine in hypertrophic scarring. IL-15 expression was compared in skin biopsies of hypertrophic scars (HS) both in active (AHS) and in remission (RHS) phases, in normotrophic scars (NTS) and in normal skin using reverse transcriptase-polymerase chain reaction and immunohistochemistry. IL-15 expression in HS was significantly higher than in NTS or normal skin. Furthermore, AHS expressed higher levels of IL-15 than RHS. Immunohistologic analysis of AHS samples showed strong IL-15 immunoreactivity in keratinocytes and Langerhans cells in the epidermis and in macrophages, fibroblasts, and dermal dendritic cells in the dermis. High levels of IL-15 expression in AHS correlated with abundant infiltration of activated CD3+ cells. Ex vivo experiments indicate that IL-15 can sustain the proliferative response of T cells derived from AHS but not from RHS and NTS. In addition, IL-15 prevents both cytokine deprivation and activation-induced apoptosis of T cells derived from AHS. Taken together, these results suggest that IL-15 can be involved in the recruitment, proliferation, and apoptosis inhibition of T cells in AHS. The findings that the evolution from an AHS to a RHS is associated with a decrease in IL15 expression, and with a loss of IL-15 responsiveness in ex vivo-cultured T cells, indicate that this cytokine plays an important role in the biology of pathologic scar formation.

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.

[Reconstructive strategies in head and neck cancer: case history review from 1992 to 1997 (154 cases)]. / Strategie ricostruttive in oncologia cervico-cefalica: revisione della casistica (154 casi) degli anni 1992-97.

Technological progress in reconstructive surgery, in particular the use of pedunculated or free flaps, has given new impetus to head and neck dissection. This stems from the fact that such techniques provide greater oncological radicality, reduce the number of severe post-operative complications and give better quality of life. The present study examines 154 patients suffering from upper aero-digestive tract neoplasms (131 males and 23 females; age range 23-82 years) who had undergone radical surgery. Reconstruction was performed with flaps in 154 cases: 119 pedunculated flaps (102 large myocutaneous pectoral and 17 temporal muscle flaps) and 35 free flaps (18 radial osteofasciocutaneous, 13 radial fasciocutaneous and 4 omentum flaps). Analysis of the individual districts showed that the flap of choice was the temporal muscle flap when surgery involved the soft parts of the orbital-maxilly-zigomatic area and the rhinopharynx. This is because it is highly moldable and reliable. In surgery of the oral cavity and oropharynx the grand pectoral flap is most frequently used as it provides enough tissue for the reconstruction, adequately protects the vascular-nerve axis in the neck and it is quick and easy. However, the functional results are not the best and there is some alteration in the initial phases of deglutition. To reduce these problems, the authors encourage the use of free flaps which provide good results from both the functional and esthetic points of view. They are, however, more difficult to perform and this leads the authors to conclude that they should only be selected for certain patients (long life expectancy, female, young, etc.). In the center where the authors work the flap of choice is the radial fasciocutaneous or osteofasciocutaneous flap. In surgery of the hypopharynx and larynx reconstruction is normally performed with a grand pectoral myocutaneous flap, sculpted as needed for the individual case. In this region, reconstruction proves functionally satisfactory even when there is a minimum of residual mucosa. Finally, for reconstructive surgery of the apex, the omentum free flap was used as it is malleable and can be used to reconstruct broad areas of dissection. The esthetic and functional results, the low incidence of complications and the greater quality of life suggest that this type of flap be extended to the surgery of locally advanced tumors in combination with an accurate, valid reconstructive solution.

Characterization of T-cell subsets infiltrating post-burn hypertrophic scar tissues.

In this study, skin-infiltrating cells were characterized in both the active and remission phases of post-burn hypertrophic scar biopsies. Immunohistochemistry examination of active phase samples showed an abundant presence of Langerhans cells, T cells, macrophages, a low presence of natural killer cells and the lack of B lymphocytes. In active hypertrophic scars T lymphocytes infiltrate deep into the superficial dermis and are also observed in the epidermis: CD3+ cells were present at about 222 +/- 107 per 0.25 mm2. In particular the analysis of lymphocyte subpopulations showed that CD4+ T cells predominate in the dermis as well as in the epidermis of active hypertrophic scars whereas CD8+ cells were less well represented (CD4/CD8 ratio is 2.06). This distribution was also shown in remission phase samples and in normotrophic scar specimens, although the lymphocyte number was significantly lower. Approximately 70 per cent of T lymphocytes present in the tissue involved in active phase hypertrophic scar samples were activated (positive with anti-HLA-DR and IL-2 receptor antibodies) which is significantly higher than remission phase hypertrophic and normotrophic scars, in which positivity was 40 and 38 per cent, respectively. Upon activation, the lesional lymphocytes release several cytokines, locally and transiently, that interact with specific receptors in response to different stimulation. Central to the immune hypothesis of hypertrophic scars is that some of the T-cell lymphokines act on keratinocytes, fibroblasts and other cell types to induce changes characteristic of these scars. The presence and close proximity of activated T lymphocytes and antigen-presenting cells of various phenotypes in both the epidermis and dermis of hypertrophic tissues provides strong circumstantial evidence of a local immune response. However, the manner in which T cells achieve and maintain their activated state in hypertrophic tissues is not yet known, and both antigen-dependent and independent mechanisms may contribute.

Similar ectopic expression of ICAM-1 and HLA class II molecules in hypertrophic scars following thermal injury.

In previous studies we have shown that HLA Class II antigens are expressed by keratinocytes and fibroblasts in hypertrophic scars. Because of the potential role of immunological events in the pathogenesis of hypertrophic scars, in the present study we have tested hypertrophic scars for the expression of intercellular adhesion molecule-1 (ICAM-1), a molecule which plays an important role in immunological phenomena. Immunoperoxidase staining with anti-ICAM-1 MoAb of 10 hypertrophic scar samples detected this molecule on epidermal keratinocytes and on about 30 per cent of fibroblasts at the site of lymphoid infiltration. The expression of ICAM-1 in hypertrophic scars was similar to that of HLA Class II antigens. Since the concomitant expression of ICAM-1 and HLA Class II by keratinocytes is known to enhance their antigen-presenting properties, the present results support the possibility that immunological events play a role in the disruption of the normal processes of wound healing and tissue remodelling which result in hypertrophic scars.

Altered biosynthesis of tumour necrosis factor (TNF) alpha is involved in postburn hypertrophic scars.

The present study shows that the decrease of TNF alpha in postburn hypertrophic scars is due to a decrease in the steady-state level of TNF alpha mRNA and thus to an altered biosynthesis of the cytokine. Thirteen scars, including seven hypertrophic and six normotrophic scars, were tested for TNF alpha mRNA production by a semiquantitative reverse polymerase chain reaction (PCR) method. TNF beta and beta actin were tested as a control. Six out of six normotrophic scar samples amplified with primers for TNF alpha showed a positive PCR signal up to the 1:32 dilution. On the contrary all the hypertrophic tested samples (7/7) had a positive PCR signal only at the 1:1 or 1:2 dilution. All samples, both normotrophic and hypertrophic, were homogeneous as to TNF beta production.

TNF production and hypertrophic scarring.

The percentage of TNF alpha- and beta-positive cells was analyzed in hypertrophic scar (N = 13), normotrophic scar (N = 7), and normal skin (N = 6) biopsies using monoclonal antibodies and immunoperoxidase staining of cryostat tissue sections. Samples were first characterized for infiltrating cells. In hypertrophic samples there was a significant increase in activated infiltrating cells, capable of producing TNF beta and IL-1 beta. In contrast, the percentage of TNF alpha-positive cells was significantly lower than that detected in normotrophic scars. In fact, in hypertrophic scar samples a positive staining with anti-TNF alpha mAb was restricted to 8% of tissue-infiltrating cells compared to 35.4% of the cells present in normotrophic scars; 12% of infiltrating cells were stained in normal skin sections. These results suggest that TNF alpha may be important for normal wound healing and that hypertrophic scarring might be partially a consequence of a low amount of TNF alpha.

The HLA-DR beta 16 allogenotype constitutes a risk factor for hypertrophic scarring.

Nineteen patients that had developed hypertrophic scars subsequent to thermal injury were typed for HLA class II allogenotypes with the restriction fragment length polymorphism technique. A significant association was found with DR beta 16 (pc = 1.45 x 10(-4); relative risk = 12.25). This finding adds evidence to other data suggesting that immunologic phenomena are involved in pathologic scarring. Moreover, the results presented here have allowed an identification of a genetically determined risk factor for hypertrophic scar formation located in the HLA region.

Anomalous expression of HLA class II molecules on keratinocytes and fibroblasts in hypertrophic scars consequent to thermal injury.

Immunoperoxidase staining of skin sections obtained from 11 hypertrophic scars, six normotrophic scars and three samples of normal skin were performed using anti-HLA monoclonal antibodies (HLA-DR, -DQ, class I), anti-interleukin-2 receptor (IL-2R) and anti-CD1. Sections from all hypertrophic scars showed an anomalous expression of HLA-DR molecules on keratinocytes and fibroblasts. Moreover hypertrophic scars were characterized by dense infiltrates of IL-2R-positive cells and by the presence of abundant Langerhans (CD1+) cells in the epidermis and dermis. These results support the hypothesis that immunologic mechanisms play an important role in hypertrophic scarring and point to an involvement of cell-mediated immune phenomena.

[Comparison of occupational and home accidents as a cause of severe burns. The experience of a large burn center in an industrial city]. / Confronto fra infortuni sul lavoro e incidenti domestici come causa di ustioni gravi. L'esperienza di un centro grandi ustionati di una città industriale.

Among acute "traumatisms", occupational and domestic accidents chiefly share burn. To compare these two causes of severe burns, we examined clinical records of patients hospitalized from January 1986 to February 1989 in the "Grand Burns Center" at the C.T.O. hospital in Turin. Data exclusively refer to patients over 12 years old. 61 out of 313 cases (19%) were due to occupational burns, 221 (71%) to domestic ones (left cases including burns occurred in different surroundings). Males predominance was very high (95%) in the occupational settings, lower though still relevant (60%) in the domestic ones. The topographic distribution of the burns did not show any relevant difference. Similarly, the two groups did not differ as the affected percent of the body surface area (BSA) is concerned: in both cases burns extended cases. Decreased patients were fairly more numerous among the domestic burns (33%) as compared to the occupational ones (18%). The overwhelming majority (90.5%) of domestic burns were caused by fire; such a predominance, though present, was lower (68.8%) among occupational accidents. More in detail, domestic burns were caused as follows: alcohol spraying to stir a fire (26%), gas burst (25%), flammable substances exposed to heat sources (18%), hot water or different liquid (8%), fall over heating devices (6%), fires from cigarettes in bed (5%), kitchen stoves (with or without clothing fire) (5%), brushwood burning (4%), other (3%). It is worth noting that in as many as 40% of the cases of domestic burns patients were affected by a pre-existing neuro-psychic disorder, namely: personality disorders (15%), psychiatric disorders (%), epilepsy (9%), mental debility (7%).

[Behavior of complement factors and plasma proteins in burns]. / Comportamento di alcuni fattori del complemento e di alcune proteine plasmatiche nella malattia da ustione.

The behaviour of three complement components (C3, C4 and C3 activator), alpha 1, alpha 2, IgA, IgG, IgM, total proteins, and gamma globulins was followed 114 patients at the C.T.O. Turin, Burns Centre with burns covering from 15% to over 70% of the body surface. Forty-two died within a relatively short time. In the remaining 72, the parameters were studied almost daily for over 30 days, or even until a final cure was obtained. The complement data and, more particularly, the distinct increased in alpha-globulins made it clear that burns can be acute inflammations. In addition, initial immune depression is followed by a prompt response of the complement system (responsible for aspecific immunity). That this change is vital in the progress of the disease may be deduced from the fact that complement component levels were constantly below normal in the patients who died.

Late results following treatment of deep burns of the hands.

During a 10-year period, 467 patients with burns involving the hands have been treated, 290 of whom during the past 5 years. Two groups of patients were examined: the first were those who had received treatment between 1967 and 1971 using the exposure method and the reconstruction with skin grafts only after the spontaneous separation of the eschars, and the second, using the closed method and early or late excision of the necrotic tissue followed by covering with split-thickness grafts. In this second group are included also those patients whose burns can be classified as medium depth at the time of admission but in whom experience has shown that one is dealing with lesions with a tendency to become deeper during the post-burn period. For these cases a dermabrasion of the lesions was performed without covering with free grafts. In the cases subjected to surgery using the technique of tangential excision and dermabrasion in order to reach the more difficult areas such as the interdigital spaces, dermabrasion was only performed between the 2nd and the 28th day. The removal of the burned tissue was followed by covering with free grafts, except in those cases in which the depth was in doubt. The results obtained have demonstrated that in the first group the scars have led to serious invalidating consequences which have necessitated long and complex surgical reconstruction programmes. In the second group almost complete function has been restored with the aid of only minimal surgical correction, most often in the interdigital spaces. We would like to emphasize the usefulness of surgery in those cases on the borderline between medium and full thickness. The tendency of these lesions to become deeper has often led to scars which are very similar to those following the deep lesions.

Considerations on early surgery in the treatment of extensive burns.

The results obtained with early surgical treatment of burns have been re-examined from various aspects. Early escharectomy, which tranforms the necrobiotic tissue into a surgical lesion, reduces the chemical factors of inflammation, lowers the lactic acid level and depresses the activity and disordered proliferation of the fibroblasts and the consequent laying down of immature collagen which is responsible for the pathological evolution of the burn scar. The removal of toxic material with proteasic activity, the reduction in the risk of sepsis, the saving of work for the immunopoietic mechanism, a reduction in the weight loss through improved nitrogen balance and an increase in the anabolic phase of muscular metabolism by early movement as well as a shortening of the period of hospitalization--all are factors in favour of the early surgical technique. Better healing is obtained by the elimination of the necrotic tissue, a reduction in the haematologic tissue inflammation mediators, an increase in the antibacterial defence following the reconstruction of the skin surface with covering materials and the rapid articular reduction; not to mention the inhibition of the formation of granulation tissue.