Subvacuum environment-enhanced cell migration promotes wound healing without increasing hypertrophic scars caused by excessive cell proliferation.

Cell migration and proliferation are conducive to wound healing; however, regulating cell proliferation remains challenging, and excessive proliferation is an important cause of scar hyperplasia. Here, we aimed to explore how a subvacuum environment promotes wound epithelisation without affecting scar hyperplasia. Human immortalized keratinocyte cells and human skin fibroblasts were cultured under subvacuum conditions (1/10 atmospheric pressure), and changes in cell proliferation and migration, target protein content, calcium influx, and cytoskeleton and membrane fluidity were observed. Mechanical calcium (Ca2+ ) channel blockers were used to prevent Ca2+ influx for reverse validation. A rat wound model was used to elucidate the mechanism of the subvacuum dressing in promoting healing. The subvacuum environment was observed to promote cell migration without affecting cell proliferation; intracellular Ca2+ concentrations and PI3K, p-PI3K, AKT1, p-AKT 1 levels increased significantly. The cytoskeleton was depolymerized, pseudopodia were reduced or absent, and membrane fluidity increased. The use of Ca2+ channel blockers weakened or eliminated these changes. Animal experiments confirmed these phenomena and demonstrated that subvacuum dressings can effectively promote wound epithelisation. Our study demonstrates that the use of subvacuum dressings can enhance cell migration without affecting cell proliferation, promote wound healing, and decrease the probability of scar hyperplasia.

Trehalose promotes functional recovery of keratinocytes under oxidative stress and wound healing via ATG5/ATG7.

Wounds are in a stressed state, which precludes healing. Trehalose is a stress metabolite that protects cells under stress. Here, we explored whether trehalose reduces stress-induced wound tissue damage. A stress model was prepared by exposing human keratinocytes to hydrogen peroxide (H2O2), followed by trehalose treatment. Trehalose effects on expression of the autophagy-related proteins ATG5 and ATG7 and cell proliferation and migration were evaluated. For in vivo verification, a wound model was established in Sprague-Dawley rats, to measure the effects of trehalose wound-healing rate and reactive oxygen species (ROS) content. Histological changes during wound healing and trehalose's effects on ATG5 and ATG7 expression, necrosis, and apoptosis were examined·H2O2 stress increased ATG5 and ATG7 expression in vitro, but this was insufficient to prevent stress-induced damage. Trehalose further increased ATG5/ATG7 levels, which restored proliferation and increased migration by depolymerizing the cytoskeleton. However, trehalose did not exert these effects after ATG5 and ATG7 knockout. In vivo, the ROS content was higher in the wound tissue than in normal skin. Trehalose increased ATG5/ATG7 expression in wound tissue keratinocytes, reduced necrosis, depolymerized the cytoskeleton, and promoted cell migration, thereby promoting wound healing.

Synergistic Effects of Quercetin-Modified Silicone Gel Sheet in Scar Treatment.

Both silicone gel and quercetin are effective in scar treatment but have different action mechanisms. Quercetin is mainly applied in the gel form and can lead to poor adhesion of silicone gel sheet; therefore, they cannot be combined in clinical use. In this study, a silicone gel sheet that releases quercetin in a sustained manner for 48 hours was successfully developed. Four round scars (Ø: 1 cm) were made in the ears of New Zealand albino rabbits (n = 10). After scar healing, the rabbits were divided into four groups: blank control group with no treatment, silicone gel sheet group with dressing change every 2 days, quercetin group with dressing change three times daily, and combination treatment group with dressing change every 2 days. Scar assessment was performed 3 months later. Transepidermal water loss showed no difference between the combination treatment group and the silicone gel sheet group, but was lower than that in the quercetin group and the blank control group. Immunohistochemistry of CD 31 and proliferating cell nuclear antigen showed the following results: combination treatment group < silicone gel sheet group = quercetin group < blank control group. Polymerase chain reaction results showed that the expression of type-I and type-III collagen in the combination treatment group and the quercetin group was significantly lower than that in the other two groups. Thus, quercetin-modified silicone gel sheet combines the advantages of the two treatments and is more effective at inhibiting cell proliferation in scar tissue than either of the two treatments alone.

Xihuang pill potentiates the anti-tumor effects of temozolomide in glioblastoma xenografts through the Akt/mTOR-dependent pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Xihuang pill, as a famous traditional Chinese medicine formula, is used for tumor treatment in China. The anti-tumor activities and mechanisms of Xihuang pill still remain unclear. AIM OF THE STUDY: The Akt/mTOR signaling pathway plays an important role in mediating cell proliferation and apoptosis in glioblastoma. This study aimed to investigate whether Xihuang pill could potentiate temozolomide-induced apoptosis of glioblastoma U87 and U251 cells in vivo and its underlying mechanisms related to Akt/mTOR pathway. MATERIALS AND METHODS: Human glioblastoma U87 and U251 xenograft models were established. Immunocytochemistry and Western blot were performed to evaluate the anti-proliferative effect, apoptosis and Akt/mTOR signaling mediators. RESULTS: The results showed that Xihuang pill (0.5, 1 g/kg) or temozolomide (10 mg/kg) treatment alone inhibited tumor growth in glioblastoma U87 and U251 xenografts. When Xihuang pill (1 g/kg) and temozolomide (10 mg/kg) were co-administrated, the activities of antitumor growth were markedly increased. Meanwhile, Xihuang pill (0.5, 1 g/kg) or temozolomide (10 mg/kg) treatment alone decreased the levels of Ki67 and PCNA expression in glioblastoma U87 and U251 xenografts. In combination treatment group, the inhibitory effects on Ki67 and PCNA expression were significantly enhanced in glioblastoma U87 and U251 xenografts compared to temozolomide treatment alone. Examining the apoptotic index by TUNEL assay showed similar results. Furthermore, Xihuang pill markedly down-regulated the Bcl-2/Bax ratio and inhibited the activation of Akt/mTOR pathway in glioblastoma U87 and U251 xenografts. In addition, no significant signs of toxicities were related to Xihuang pill and/or temozolomide treatment. CONCLUSIONS: The present study suggested that Xihuang pill might potentiate temozolomide-induced apoptosis of glioblastoma cells in vivo through inhibiting Akt/mTOR-dependent pathway.

The Variation of Hemodynamic Parameters Through PiCCO in the Early Stage After Severe Burns.

To investigate early hemodynamics of severely burned patients via PiCCO and to discuss clinical significance of hemodynamic monitoring for burn shock resuscitation, 55 extensive burn patients were enrolled in this retrospective study. The fluid resuscitation was guided according to Chinese General Formula and adjusted with urinary output of 0.5-1.0 ml/h/kg as a resuscitation goal. All patients were diagnosed within a relatively stable condition during burn shock stage, and they received PiCCO monitoring within 6 hours after burn. The preload parameter intrathoracic blood volume index was low at first, then returned to normal. The flow parameter cardiac index and myocardial contractility parameter dPmax were gradually changed from low level in the early stage to high level in the fluid reabsorption stage. The afterload parameter systemic vascular resistance index had completely opposite tendency. The lung-related parameters extravascular lung water index and pulmonary vascular permeability index were roughly in the normal range. The change of cardiac index had a linear regression relationship with dPmax and systemic vascular resistance index but had no significant relationship with intrathoracic blood volume index. Under effective fluid resuscitation, the early hemodynamics after burn is still in dynamically changing status, characterized as transition from low cardiac output (CO)-high vascular resistance in early shock stage to high CO-low vascular resistance in fluid reabsorption stage. CO mainly depends on the myocardial contractility and vascular resistance, but not on the blood volume. Excessive fluid resuscitation cannot get normal CO. The normal value of hemodynamics cannot be used as end point of burn shock resuscitation. Dynamic observation of hemodynamics is of great importance.

Using negative pressure wound therapy on microskin autograft wounds.

BACKGROUND: Microskin autografts with conventional wrap and compression are used extensively in the treatment of skin and tissue defects. This comparative study aimed at investigation of the clinical application of negative pressure wound therapy (NPWT) in combination with microskin autografts for repair of acute and chronic wounds. METHODS: A prospective case-control study was performed from December 1, 2010-December 31, 2013 in Changhai Hospital, Shanghai. We compared a study group of patients received microskin autografting covered by NPWT with that of a control group of patients received microskin autografting covered by a conventional gauze. RESULTS: A total of 81 patients were in this study, 27 patients were allocated to the study group and 54 patients to the control group. The study group exhibited significant low infection rate and pain score during removal of inner layer at first dressing change after skin grafting compared with those of the control group (P < 0.05). The time interval between skin grafting and first postoperative change was longer in the study group than that in the control group (P < 0.01), the study group showed a significant shorter 95% wound healing time (P < 0.05), and survival rate of microskin autografts in the study group was higher than that in the control group (P < 0.05). CONCLUSIONS: NPWT is beneficial for wound closure after microskin autografts, which prolongs the interval between skin transplantation and first postoperative dressing change, reduces pain during removal of inner layer dressing, increases skin graft survival rate, and shortens wound healing time. Therefore, NPWT can be recommended for repair of acute and chronic wounds with microskin autografts.

Deficiency of Smad3 results in enhanced inducible nitric oxide synthase-mediated hypotension in lipopolysaccharide-induced endotoxemia.

BACKGROUND: Smad3 is a principal intracellular mediator of signaling for transforming growth factor ß, a cytokine involved in pleiotropic pathophysiological processes including inflammation and immunity. The function of Smad3 in regulating inducible nitric oxide synthase (iNOS) expression and septic shock has not been characterized. METHODS: Smad3(-/-) (referred hereafter as KO) and wild-type (WT) mice were injected intraperitoneally with lipopolysaccharide (LPS) to induce the septic hypotension. Mortality, blood pressure, and plasma levels of nitrite were measured. The iNOS messenger RNA and protein levels in lung, kidney, and spleen were also analyzed. RESULTS: Mice lacking functional Smad3 respond to LPS with greater mortality than their WT littermates. The high mortality of KO mice is accompanied by enhanced hypotension after intraperitoneal injection of LPS. Both KO and WT mice displayed an increase in plasma nitrite during the experimental period; however, LPS administration caused more dramatic changes in KO mice than WT mice. Likewise, the iNOS messenger RNA and protein levels in lung, kidney, and spleen were more strongly increased in KO mice than in WT mice after LPS administration. CONCLUSIONS: Defects in the Smad3 gene may increase susceptibility to the development of septic hypotension because of enhanced iNOS production.

Macrophage migration inhibitory factor counter-regulates dexamethasone-induced annexin 1 expression and influences the release of eicosanoids in murine macrophages.

Macrophage migration inhibitory factor (MIF), a pro-inflammatory cytokine and glucocorticoid (GC) counter-regulator, has emerged as an important modulator of inflammatory responses. However, the molecular mechanisms of MIF counter-regulation of GC still remain incomplete. In the present study, we investigated whether MIF mediated the counter-regulation of the anti-inflammatory effect of GC by affecting annexin 1 in RAW 264.7 macrophages. We found that stimulation of RAW 264.7 macrophages with lipopolysaccharide (LPS) resulted in down-regulation of annexin 1, while GC dexamethasone (Dex) or Dex plus LPS led to significant up-regulation of annexin 1 expression. RNA interference-mediated knockdown of intracellular MIF increased annexin 1 expression with or without incubation of Dex, whereas Dex-induced annexin 1 expression was counter-regulated by the exogenous application of recombinant MIF. Moreover, recombinant MIF counter-regulated, in a dose-dependent manner, inhibition of cytosolic phospholipase A2α (cPLA2α) activation and prostaglandin E2 (PGE2 ) and leukotriene B4 (LTB4 ) release by Dex in RAW 264.7 macrophages stimulated with LPS. Endogenous depletion of MIF enhanced the effects of Dex, reflected by further decease of cPLA2α expression and lower PGE2 and LTB4 release in RAW 264.7 macrophages. Based on these data, we suggest that MIF counter-regulates Dex-induced annexin 1 expression, further influencing the activation of cPLA2α and the release of eicosanoids. These findings will add new insights into the mechanisms of MIF counter-regulation of GC.

Pediatric burns due to hot water from water dispenser: a neglected issue that should be highly concerned.

BACKGROUND: More and more Chinese drink hot water from water dispensers while many children were scalded due to this change. The present study aimed to propose a feasible strategy for prevention. METHODS: A retrospective study was conducted for all water dispensers related pediatric burns admitted to Changhai Hospital from January 2005 to December 2009. RESULTS: The number of new cases and incidences of pediatric burns due to hot water from water dispensers was significantly increasing year after year. In the total 238 involved cases, 175 cases happened on males and 78.9% were at the age of 1 - 4 years. The burn areas were mainly located in upper extremities. All water dispensers in the surveyed families had no isolate protection devices and 85.2% of their locations were easy for children to reach. Nearly half of the children were in the same room with their guardians when injured. Total 196 burned children were playing the taps of water dispensers before injured, unfortunately, 80.6% of them have not been stopped until burned. CONCLUSION: As the kind of burns is quite serious and with bad outcome, some recommendations should be followed, such as buying water dispensers with protection devices, keeping children from touching them and so on.

Pre-hospital emergency burn management in Shanghai: analysis of 1868 burn patients.

BACKGROUND: There are few studies reporting the level of pre-hospital emergency management of burn patients and related influencing factors in China. This study is a summary of our investigation on emergency education and people's awareness about pre-hospital emergency management of burn patients in Shanghai, China, and analyses key factors influencing pre-hospital emergency management of burn patients. METHODS: The survey was conducted by questionnaire in burn patients who sought initial clinical visits at the Burn Center of Changhai Hospital (Shanghai, China) between November 2009 and December 2010, including demographic data, burn conditions, pre-hospital emergency management and education about emergency burn management. Data were statistically treated by SPSS software. RESULTS: Altogether 1868 effective questionnaire forms were collected; 33.9% of these burn patients received cooling treatment before admission and 32.2% of them used 'folk remedies' or antibiotics to treat the wound surface. Only 12.2% of these burn patients had received education about the knowledge of emergency management, mainly through public media (38.2%), relatives and friends (24.6%), Internet (15.8%), workplace (11.4%) and schools (10.1%). The result of logistic regression analysis showed that emergency education, especially via Internet and workplace, played an important role in pre-hospital emergency management, and that different channels of emergency education affected different age groups of people: network and unit education mainly affected young adults, while relatives and friends mainly affected elderly people. In addition, educational level was an important factor favourably affecting 'cooling therapy'. CONCLUSIONS: The level of emergency burn management and related education is relatively low in China at present, and it is therefore necessary to intensify education about pre-hospital emergency management to raise the level of emergency burn management. At the same time, more attention should be paid to age- and population-specific education. Finally, universal emergency education should be included in the national basic education as a long-term strategy.

Role of inhibition of p38 mitogen-activated protein kinase in liver dysfunction after hemorrhagic shock and resuscitation.

BACKGROUND: The liver is one of the organs most frequently affected by trauma and hemorrhagic shock; the exact role of p38 mitogen-activated protein kinase (MAPK) activation in response to hepatic hemorrhagic shock/resuscitation (HS/R) remains unclear. MATERIALS AND METHODS: C57Bl/6 mice were divided into four groups: sham-operated group, SB-only group, control group, and SB + HS/R group. Hepatocellular injury (aspartate aminotransferase [AST] and alanine aminotransferase [ALT]) and tumor necrosis factor (TNF-α) and interleukin (IL-1ß) messenger ribonucleic acid (mRNA) expression in the liver were assessed 6 h after resuscitation, p38 MAPK activation in the liver was assessed at 30 min after resuscitation. RESULTS: p38 MAPK activation was higher in the control group than other groups 30 min after resuscitation. p38 MAPK activation level in the SB + HS/R group did not change significantly compared with that of sham and SB-only groups, but was significantly lower than that in the control group. The TNF-α mRNA expression in the control group was significantly higher than that in the sham group. The TNF-α mRNA levels after HS/R in the SB + HS/R group were significantly lower than those in the control group and were roughly the same as those in the sham and SB-only groups. IL-1ß mRNA expression showed similar changes in the four groups. Serum ALT and AST levels in the control group were significantly higher than those in the sham group. The increase in serum ALT and AST levels after HS/R in the SB + HS/R group was significantly less pronounced than that in the control group and markedly higher than that in the sham group. CONCLUSIONS: p38 MAPK was phosphorylated during the HS/R process. Inhibiting the activation of p38 MAPK may attenuate HS/R injury to the liver.

Epidemiology and outcome analysis of severe extensive burns: a 12-year summary of 103 cases in a burn center in China.

The purpose of this article is to improve the treatment of severe extensive burns (SEB) patients by summarizing treatment experience in recent 12 years in China and analyzing the follow-up quality of life (QOL) in these patients. Clinical data and rescue measures of 103 SEB patients (≥70% TBSA) admitted in a burn center in Shanghai between 1997 and 2009 were reviewed, and QOL and hand function of those who survived more than 2 years were assessed by Brief Version of Burn Specific Health scale-B and Michigan Hand Outcome Questionnaire. Of these, 76.7% were caused by flames and 15.5% caused by scald. The median burn area was 87.5% (interquartile range, 77.0-95.0%) TBSA, of which third-degree burns accounted for 56.5% (interquartile range, 25.8-80.0%) TBSA; 71.8% were complicated by inhalation injury. The occurrence of in-hospital complications was 75.7%, with the respiratory system complications predominating (49.5%). The fatality rate was 28.2%, mainly due to sepsis and multiple organ dysfunction syndrome. Work, body image, and heat sensitivity got the lowest Brief Version of Burn Specific Health scale-B scores in all nine domains, and Michigan Hand Outcome Questionnaire scores were also relatively poor. Flame burns remain to be the main cause of SEB in China in recent 12 years. Treatment is still challenged because of the depth and extensive burn area and high occurrence of multiple system complications. How to ameliorate QOL of SEB patients, intensify the functional rehabilitation, and improve their physical appearance in particular remain to be a crux.

Evaluation of long term health-related quality of life in extensive burns: a 12-year experience in a burn center.

OBJECTIVES: We sought to evaluate the long term health-related quality of life (HRQOL) in patients survived severely extensive burn and identify their clinical predicting factors correlated with HRQOL. METHODS: A cross-sectional study was conducted in 20 patients survived more than 2 years with extensive burn involving ≥70% total body surface area (TBSA) between 1997 and 2009 in a burn center in Shanghai. Short Form-36 Medical Outcomes Survey (SF-36), Brief Version of Burn Specific Health Scale (BSHS-B) and Michigan Hand Outcome Questionnaire (MHQ) were used for the present evaluation. SF-36 scores were compared with a healthy Chinese population, and linear correlation analysis was performed to screen the clinical relating factors predicting physical and mental component summary (PCS and MCS) scores from SF-36. RESULTS: HRQOL scores from SF-36 were significantly lower in the domains of physical functioning, role limitations due to physical problems, pain, social functioning and role limitations due to emotional problems compared with population norms. Multiple linear regression analysis demonstrated that only return to work (RTW) predicted improved PCS. While age at injury, facial burns, skin grafting and length of hospital stay were correlated with MCS. Work, body image and heat sensitivity obtained the lowest BSHS-B scores in all 9 domains. Improvements of HRQOL could still be seen in BSHS-B scores in domains of simple abilities, hand function, work and affect even after a quite long interval between burns and testing. Hand function of extensive burn patients obtained relatively poor MHQ scores, especially in those without RTW. CONCLUSIONS: Patients with extensive burns have a poorer quality of life compared with that of general population. Relatively poor physical and psychological problems still exist even after a long period. Meanwhile, a trend of gradual improvements was noted. This information will aid clinicians in decision-making of comprehensive systematic regimens for long term rehabilitation and psychosocial treatment.

Unplanned decannulation of tracheotomy tube in massive burn patients: a retrospective case series study.

BACKGROUND: Unplanned extubation is associated with adverse outcomes in intensive care unit. The massive burn patient differs from other critically ill patients in many ways. However, little is known about the unplanned decannulation (UD) in Burn Intensive Care Unit. This paper describes the special features of the circumstances and outcome of UD of tracheotomy tube in massive burn patients. METHODS: A case series study was performed between January 1999 and December 2008 and UD of tracheotomy tube was analyzed retrospectively. A total of 21 patients with 29 UD events were identified. Demographic data, diagnosis, intervention, UD events and outcome of UD patients were collected. Differences in proportions were compared using the chi-square (χ(2)) or Fisher's exact test. RESULTS: Patients with UD were often burned with head and neck (67%) and combined with inhalation injury (62%). The majority of them (76%) were transferred patients, occurred early (55%) and were accidental UD (79%). UD events tended to happen in day shift (90%) and to be associated with the medical procedure that was performing by caregivers at besides (79%). Loose of the stabilizing rope, medical procedure and tracheotomy malposition were the main causes of UD. Early UD and reintubation failure were associated with patients' death. CONCLUSIONS: UD happened to massive burn patients can lead to patient death. Careful management of respiratory tract was essential for massive burn patients.

A new strategy of promoting vascularization of skin substitutes by capturing endothelial progenitor cells automatically.

How to promote vascularization of a skin substitute is the key to successful skin transplantation. Current methods are mainly through releasing angiogenesis-related factors (ARF) or seeding angiogenesis-related cells (ARC), but the efficacy of these methods is not satisfactory, because angiogenesis needs participation of multiple factors, extracellular matrix and related cells. The latest research has demonstrated that endothelial progenitor cells (EPCs) originating from bone marrow and existing in peripheral blood are the key element participating in revascularization of adult tissues. They directly participate in both stem cell vasculogenesis of ischemic tissues and local angiogenesis. We therefore hypothesize whether it is possible to construct a new skin substitute and use it to mobilize EPCs in bone marrow to peripheral circulation and capture EPCs automatically as a simple and effective method of promoting vascularization of the skin substitute for the sake of improving its post-transplant survival.

An epidermal stem cells niche microenvironment created by engineered human amniotic membrane.

How to amplify epidermal stem cells (ESCs) rapidly is a challenging crux in skin tissue engineering research. The present study describes the preparation of 3D micronized (300-600 µm) amniotic membrane (mAM) by means of repeated freeze-thawing cycles to deplete cell components and homogenized with a macrohomogenizer in liquid nitrogen. This newly prepared mAM not only possessed the characteristics of a microcarrier but completely retained the basement membrane structure and abundant active substances such as NGF, HGF, KGF, bFGF, TGF-ß1 and EGF in the AM matrix. The result showed that mAM combined with rotary cell culture system (RCCS) was able to amplify ESCs quickly. The relative cell viability at day 7 and 14 was significantly higher than that of the conventional 2D plate culture (326 ± 28% and 535 ± 47% versus 232 ± 21% and 307 ± 32%, P < 0.05). In addition, the new method was able to prevent cell differentiation effectively and retain the characteristics of stem cells. When mAM loaded with ESCs (ESC-mAM) was further transplanted to full-thickness skin defects in nude mice, ESCs survived well and formed a new epidermis. Four weeks after transplantation, papilla-like structures were observed, and collagen fibers were well and regularly arranged in the newly formed dermal layer. In conclusion, the mAM as a novel natural microcarrier possesses an intact basement membrane structure and bioactivities. It not only provides the microenvironment similar to the stem cell niche within the human body favorable for ex vivo culture and amplification of ESCs but can be used as the dermal scaffold in constructing a skin substitute containing ESCs for the repair of full-thickness skin defects.

Successful treatment of a patient with an extraordinarily large deep burn.

BACKGROUND: Treatment of extraordinarily large deep burns remains a huge clinical challenge. CASE REPORT: This article is a summary of our experience with the treatment of a patient with an extraordinarily large deep burn (99.5% TBSA and 23% fourth degree burn) by using the "microskin autografting and alloskin repeated grafting" method to close the deep burn wound because of scarcity of skin sources of the patient. CONCLUSIONS: The patient has been observed for 2 years, and is able to face the reality of life peacefully with the support of his family.

Risk factors and prognosis of lower digestive tract haemorrhage in severe burns: a 12-year retrospective analysis.

OBJECTIVE: To explore the risk factors relating to lower digestive tract haemorrhage in severe burns and summarise the experience in clinical diagnosis and treatment. METHOD: General data of 103 patients with severe extensive burns (EBs) admitted to our burn centre in Shanghai between 1997 and 2009 were reviewed retrospectively. The risk factors relating to EB-complicated lower digestive tract haemorrhage were analysed systematically with respect to the clinical features and experiences in treatment, and prognosis. RESULTS: Of the 103 severe EBs, five developed lower digestive tract haemorrhage with an occurrence of 4.9%. Four of them were proved to have multiple mucosal erosions in caecum, colon and rectum, and the remaining one was proved rectal ulcerative haemorrhage. In comparison with upper digestive tract haemorrhage, lower digestive tract haemorrhage in the present group was characterised by a longer duration (median 4.0 days, interquartile range (IQR) 1.5-14.5 days vs. median 2.0 days (IQR 1.0-3.0 days), P < 0.05). Deep burns, especially fourth-degree burns, with complications of severe systemic infection, formed the main risk factors relating to lower digestive tract haemorrhage in severe EB patients. CONCLUSION: Severe EB-complicated lower digestive tract haemorrhage is a critical condition in burns, which usually have deep wounds with severe infection surfaces that are difficult to deal with. Enteroscopic haemostasis in controlling lower digestive tract haemorrhage is usually ineffective. Clinical experiences indicate that early management of the wound with effective preventive and therapeutive measures for infection control may be a good choice in the prevention and treatment of lower digestive tract haemorrhage leading to improvement in its prognosis.