Bacterial flora of Hirudo medicinalis and their antibiotic sensitivities in the Middle Black Sea Region, Turkey.

The rate of infectious complications of leech therapy is almost 20% because Hirudo medicinalis has endosymbiotic bacteria. The aim of this study was to determine the bacterial flora of H. medicinalis and their antibiotic sensitivities in a region in Turkey. Sixteen adult leeches were collected in Middle Black Sea region, Turkey. They were rubbed onto blood agar plates directly under ether anesthesia to obtain surface cultures. They were then killed to obtain mouth and gut cultures. Culture swabs were applied to blood agar, eosin methylene blue agar, and ampicillin blood agar plates. Gut contents were applied to blood culture medium as well. Bacteria were isolated in 15 of 16 leech surfaces, in 7 of 16 mouths, and in 15 of 16 guts. Isolated bacteria were identified with Analytical Profile Index 32 E and Analytical Profile Index 20 NE (fermentative and nonfermentative respectively). Most common types of cultured bacteria were Aeromonas hydrophila (N = 25), Ochrobacter anthropi (N = 23), nonfermenting Gram-negative rods (N = 12), Acinetobacter lwoffi (N = 3), and A. sobria (N = 2) in 73 isolates. A standard disk diffusion test was performed on isolated bacteria. All isolates were 100% susceptible to ciprofloxacin, cefotaxime, ceftazidime, gentamicin, and trimethoprim/sulfamethoxazole. Because leeches are carriers of Aeromonas and other bacteria, appropriate antibiotic prophylaxis should be administrated to the patient who needs leech therapy. Antibacterial agents can be determined by the resistance pattern of the bacterial flora of regional H. medicinalis.     

Postprandial Aeromonas hydrophila cultures and antibiotic levels of enteric aspirates from medicinal leeches applied to patients receiving antibiotics.

Increasing use of medicinal leeches has been accompanied by increasing numbers of reports of Aeromonas hydrophila infections after leech application on or near damaged tissue. We examined the enteric contents of postprandial leeches after their application to patients receiving antibiotics. We found measurable levels of antibiotic in the leech enteric contents, and in leeches applied to patients receiving an antibiotic effective against Aeromonas hydrophila, there was a significant decrease in positive Aeromonas enteric cultures. Suppression of leech enteric bacteria by antibiotic administration to the patient may be an effective strategy to prevent invasive infection by Aeromonas hydrophila as well as bacterial colonization of devitalized tissue that could be the source of late infection. Clinical studies will be required to clarify whether suppression of leech enteric flora results in a decrease in infections associated with leech use.     

Sensitivities of Aeromonas hydrophila cultured from medicinal leeches to oral antibiotics

Infections associated with medicinal leech application are caused by Aeromonas hydrophila, an organism that resides in the leech gut. We cultured the intestinal tracts of 25 leeches and evaluated the efficacy of oral antibiotics against Aeromonas hydrophila. Cultures of this organism showed no sensitivity to ampicillin and inconsistent sensitivity to cephalothin (equivalent to cephalexin). The Aeromonas hydrophila cultures did show consistent sensitivity to ciprofloxacin, tetracycline, and trimethoprim-sulfamethoxasole. These three antibiotics should be considered if oral antibiotic coverage is used in association with leech application.     

Aeromonas hydrophila infections following use of medicinal leeches in replantation and flap surgery.

Aeromonas hydrophila infections are a recognized complication of postoperative leech application, and can occur with measurable frequency in populations of patients treated with leeches. We review 11 previously reported leech-related Aeromonas infections and analyze seven unreported cases. These infections range from minor wound complications to extensive tissue loss and sepsis. Often, these infections followed leech application to tissue with questionable arterial perfusion. Onset of clinical infection in these patients ranged from within 24 hours of leech application to 10 days or more after leech application. Late infections may represent bacterial invasion from colonized necrotic tissue. Based on these observations, we recommend that leech applications be restricted to tissue with arterial perfusion to minimize contamination of necrotic tissue. We also recommend that patients treated with leeches receive antibiotics effective against Aeromonas hydrophila before leech application. Patients treated with leeches and discharged with eschars or open wounds might benefit from oral antibiotic therapy until wound closure. These precautions may minimize or eliminate this complication of leech use.     

Antibiotic sensitivities of Aeromonas hydrophila cultured from medicinal leeches

Increased use of medicinal leeches (Hirudo medicinalis) for the treatment of venous congestion in flaps and replanted parts has coincided with reports of soft tissue infections following leech application. We cultured the gullets of 20 medicinal leeches to re-examine the antibiotic sensitivities of Aeromonas hydrophila, the leech enteric organism associated with reported infections. These isolates reflected reported resistance to penicillin and first generation cephalosporins as well as sensitivity to gentamicin, tetracycline and chloramphenicol. Additionally, the cultures were sensitive to cefamandol, cefoxitin and two third generation cephalosporins (cefoperazone and cefotaxime). These findings suggest that cefamandol, cefoxitin and some third generation cephalosporins may have a role as perioperative antibiotics in replantation and flap surgery. These antibiotics might provide prophylaxis against Aeromonas hydrophila infection when leech use is required.     

Medicinal leeches and the microsurgeon: a four-year study, clinical series and risk benefit review

Background: There are case reports and small series in the literature relating to the use of medicinal leeches by plastic surgeons; however, larger series from individual units are rare. The aim of this article is to present a comprehensive 4‐year case series of the use of medicinal leeches, discuss the current evidence regarding indications, risks, and benefits and highlight the recent updates regarding leech speciation. Methods: Patients prescribed leeches in a 4‐year period (July 2004–2008) were collated from hospital pharmacy records (N = 35). The number of leeches used, demographic, clinical, and microbiological details were retrospectively analyzed. Results: Thirty‐five patients were treated with leeches. The age range was 2 to 98 years (mean = 49.3). Leeches were most commonly used for venous congestion in pedicled flaps and replantations. Blood transfusions were necessary in 12 cases (34%) [mean = 2.8 units, range 2–5 units]. Our infection rate was 20% (7/35) including five infections with Aeromonas spp. (14.2%). The proportion of patients becoming infected after leech therapy was significantly greater in the group of patients that did not receive prophylactic antibiotic treatment (Fisher's Exact test P = 0.0005). In total, 14 cases (40%) were salvaged in entirety, in 7 cases 80% or more, in 2 cases 50 to 79%, and in 1 case less than 50% of the tissues were salvaged. In 11 cases (31%), the tissues were totally lost. Conclusion: Our study highlights both the benefits and the risks to patients in selected clinical situations and also the potential risks. The routine use of antibiotic prophylaxis is supported. In view of the emerging evidence that Hirudo verbana are now used as standard leech therapy, and the primary pathogen is Aeromonas veronii, until a large prospective multicenter study is published, large series of patients treated with leeches should be reported. © 2011 Wiley‐Liss, Inc. Microsurgery, 2011.     

Digit replantation applying the leech Hirudo medicinalis

Digits that were formerly assessed as nonreplantable may now be replanted with the help of the leech Hirudo medicinalis. The early experience with a series of patients who had relative contraindications for replantation is reported. In each case, venous repair was either marginal or technically impossible. Postoperative venous congestion developed following replantation and was treated with the application of medicinal leeches. Patient acceptance was high, and no infections developed. No patient required transfusion. The authors conclude that the use of medicinal leeches shows promise as a safe and effective method of providing temporary venous drainage in replanted digits.     

The consequences of suppression of anaerobic bacteria

Anaerobic bacteria such as Bacteroides fragilis, Peptostreptococcus species, and Fusobacterium species, when accompanied by aerobic bacteria or in the presence of dead tissue, can cause severe infections. This article discusses the most common type of anaerobic infection, i.e., infection after colonic contamination of the abdominal cavity and soft tissues. Colonic anaerobes rarely cause infections as solitary pathogens. Mixed infections of aerobes and anaerobes are treated by source control, surgical drainage and debridement, and combination antibiotic therapy. Antimicrobial treatment should cover both anaerobes and aerobes; treatment of mixed infections with anti-anaerobic agents alone is likely to result in abscess formation. Recent trends toward cost cutting and the advent of antibiotics with good coverage of both aerobes and relevant pathogenic anaerobes have led to increased single-agent therapy with cefoxitin, cefotetan, ampicillin/sulbactam, imipenem/cilastatin, ticarcillin/clavulanate, trovafloxacin/alatrofloxacin, and piperacillin/tazobactam. In the past 15 years, research has begun to focus on the gut barrier, particularly on the beneficial effects of anaerobic microflora. Directing antibiotic therapy against the anaerobe when it is involved in clinical infection is important; however, the negative consequences of anti-anaerobic antibiotic therapy on the beneficial effects of normal distal gut colonization must also be considered.     

Aeromonas hydrophila water-associated traumatic wound infections: a review

The bacterium Aeromonas hydrophila is commonly found in natural bodies of water, and is a potential invasive pathogen for those who suffer trauma while submerged in water. Five patients treated by the authors and 18 previously reported patients were reviewed to further define the characteristics of A. hydrophila wound infections. Although Aeromonas has been isolated from salt and brackish water, all 23 cases occurred following contact with fresh water. Signs of infection usually appeared 8-48 hours following puncture or laceration injury. The foot or leg were most commonly involved. Infection was frequently rapidly progressive; fascia, tendon, muscle, bone, or joint involvement occurred in 39% of cases. In addition to A. hydrophila, other aerobic and anaerobic bacteria were found in 48% of cases. Aeromonas infection should be suspected in cases of early and rapidly progressive wound infection following trauma in fresh water. Broad-spectrum antimicrobial therapy and appropriate surgical care should be promptly instituted.     

Antimicrobial resistance in the intensive care unit: the use of oral non-absorbable antimicrobials may prolong the antibiotic era

Antimicrobial resistance is a significant problem in the intensive care unit. Ill patients carry abnormal bacteria, amongst which are the causative organisms of many of the nosocomial infections. Overgrowth of these bacteria predisposes to infection. Further, the excretion of systemically administered antibiotics into the gut selects resistant bacteria from this population. In eliminating overgrowth, oral non-absorbable antibiotics prevent infections and prevent the development of antibacterial resistance. This paper discusses the limited effect of traditional approaches in preventing antibiotic resistance. These rely on restriction of classes of antibiotics used, or by restricting antibiotic use by more specific (often invasive) diagnostic techniques (such as protected brush specimens) for the diagnosis of pneumonia. In contrast we describe the experience of three centres using oral non-absorbable antibiotics finding that antibiotic resistance is not a significant clinical problem. In one 20-bed paediatric intensive care, admitting 1000 children per year, of 390 admissions who stayed more than four days 12 episodes of infection (in eight individuals) were caused by antibiotic resistant bacteria. Oral non-absorbable antibiotics prevent both infections and the emergence of antibiotic resistant bacteria.     

Probiotics or pro‐healers: the role of beneficial bacteria in tissue repair

Probiotics are beneficial microorganisms, known to exert numerous positive effects on human health, primarily in the battle against pathogens. Probiotics have been associated with improved healing of intestinal ulcers, and healing of infected cutaneous wounds. This article reviews the latest findings on probiotics related to their pro‐healing properties on gut epithelium and skin. Proven mechanisms by which probiotic bacteria exert their beneficial effects include direct killing of pathogens, competitive displacement of pathogenic bacteria, reinforcement of epithelial barrier, induction of fibroblasts, and epithelial cells' migration and function. Beneficial immunomodulatory effects of probiotics relate to modulation and activation of intraepithelial lymphocytes, natural killer cells, and macrophages through induced production of cytokines. Systemic effects of beneficial bacteria and link between gut microbiota, immune system, and cutaneous health through gut–brain–skin axes are discussed as well. In light of growing antibiotic resistance of pathogens, antibiotic use is becoming less effective in treating cutaneous and systemic infections. This review points to a new perspective and therapeutic potential of beneficial probiotic species as a safe alternative approach for treatment of patients affected by wound healing disorders and cutaneous infections.     

Enterobacter asburiae and Aeromonas hydrophila: soft tissue infection requiring debridement

Enterobacter asburiae and Aeromonas hydrophila are gram-negative bacilli that have been isolated in soil and water. Enterobacter asburiae can cause an array of diseases, and exposure to A hydrophila can cause soft tissue infections, including necrotizing faciitis.A healthy-appearing 22-year-old man presented with an innocuous soft tissue injury to his leg due to an all-terrain vehicle crash. He received intravenous antibiotics and was discharged with prophylactic oral antibiotics. After the rapid onset of high fevers (102°F-103°F) <24 hours postinjury, he returned to the emergency department. Emergent surgical debridement was performed, and broad-spectrum intravenous antibiotics were started. Fevers persisted, and the patient underwent repeat extensive surgical debridement and antibiotic bead placement <30 hours after the initial surgical debridement and broad-spectrum antibiotics. Intraoperative cultures found E asburiae and A hydrophila in the wound. Following a long course of antibiotics and a skin graft, he fully recovered and had no functional deficits 1 year postoperatively.Extensive research revealed that these organisms are rare in soft tissue infections. E asburiae is opportunistic but has not been reported as a primary wound organism, and A hydrophila infections have been reported following motor vehicle crashes involving wound contamination. At presentation, it is challenging to determine rare organisms in a timely fashion; however, emergent extensive surgical intervention of an accelerated aberrant disease process should be considered to avoid catastrophic outcomes.     

Hirudo Medicinalis and the plastic surgeon.

Medicinal leech therapy is an ancient craft that dates back to ancient Egypt and the beginnings of civilisation. The popularity of Hirudo Medicinalis has varied throughout history, reaching such a peak in Europe in the early 19th century that supplies were exhausted. During the latter half of the 19th century, their use fell out of favour, as they did not fit in with the emerging concepts of modern medicine. Leeches have enjoyed a renaissance in the world of reconstructive microsurgery during recent years, and their first reported use in alleviating venous engorgement following flap surgery was reported in this journal [M Derganc, F Zdravic, Venous congestion of flaps treated by application of leeches, Br J Plast Surg 13 (1960) 187]. Contemporary plastic and reconstructive surgeons in units throughout the United Kingdom and Ireland continue to use leeches to aid salvage of failing flaps. We carried out a survey of all 62 plastic surgery units in the United Kingdom and the Republic of Ireland to assess the current extent of use, and to investigate current practice. We have shown that the majority of plastic surgery units in the UK and Ireland use leeches post-operatively and that the average number of patients requiring leech therapy was 10 cases per unit per year. Almost all units use antibiotic prophylaxis, but the type of antibiotic and combination used is variable. We outline current practice and suggest a protocol for the use of leeches. Whilst the use of leeches is widespread, the plastic surgery community has progressed little in defining indications for their use or in achieving an accepted protocol for their application in units throughout the UK and Ireland.     

初次髋膝关节置换术后假体周围感染的病原学研究

目的为有效预防及治疗感染,研究髋膝关节置换术后假体周围感染的病原菌构成与耐药率的变化趋势,评价抗感染方案的治疗效果。 方法收集华西医院骨科自2010年至2015年收治的初次髋、膝关节置换术后假体周围感染病例的相关资料。统计培养阳性率、病原菌构成与耐药率,分析病原菌构成与耐药率的变化趋势及不同抗感染方案的治疗效果。 结果共146例纳入研究,髋、膝关节置换术后假体周围感染分别为111例和35例,培养阳性率为73.97%,病原菌以革兰阳性菌为主,占55.48%,其中表皮葡萄球菌及金黄色葡萄球菌所占比例最高,分别为25.34%及15.07%;革兰阴性菌占13.01%,其中阴沟肠杆菌、铜绿假单胞菌及大肠埃希菌分别占4.79%、3.42%及2.05%。革兰阳性菌对利福平、利奈唑胺、万古霉素等较敏感,革兰阴性菌对阿米卡星、亚胺培南及头孢吡肟有较高的敏感性,但病原菌对β-内酰胺类、庆大霉素、克林霉素及部分喹诺酮类抗菌药物的耐药率较高。经验性抗感染方案多选择静脉使用万古霉素联合头孢菌素、左氧氟沙星或克林霉素,续以口服头孢克洛或头孢克洛联合利福平。对于培养阳性的病例,则根据药敏结果使用敏感抗菌药物。 结论目前假体周围感染的培养阴性率较高,应规范术前抗菌药物使用及标本的采集与培养,以提高检出率。病原菌谱复杂,以革兰阳性菌为主,病原菌对多种抗菌药物具有较高耐药性。经验性抗感染方案的抗菌谱应覆盖革兰阳性菌,尤其是葡萄球菌,待病原菌明确后需根据药敏结果制定个体化的抗感染方案。     

Leech-borne Serratia marcescens infection following complex hand injury.

Leeches are commonly used in the postoperative course of plastic surgical operations where there is venous congestion in a pedicled or free flap. They provide a temporary relief to venous engorgement whilst venous drainage is re-established. It is known that leeches can carry Aeromonas hydrophila infection, and a second or third generation cephalosporin antibiotic has traditionally been given as prophylaxis against infection. We report a new observation that leeches can carry Serratia marcescens and give rise to clinically significant infection. The implication for prophylaxis and treatment of leech-associated cellulitis is discussed.     

Antibiotic management guidelines in trauma and critical care

Many patients with severe illness or conditions like multiple trauma and severe burns are vulnerable to infection due to their depressed immune function. In addition, most patients in the intensive care unit are at increased risk of developing ventilator-associated pneumonia and catheter-related sepsis. A basic concept of antibiotic use in these guidelines is to diagnose infection and identify the pathogenic microorganism as soon as possible. We should not start inadequate empirical antimicrobial therapy in cases of undetermined infection focus or pathogen because it may increase the risk of development of antibiotic-resistant bacteria and opportunistic infections. Antibiotic use should be planned deliberately from the time of admission in patients hospitalized long time. Prophylactic antibiotic use should be restricted to a specific diagnosis or an exceptional condition. The antibiotic choice should be determined based on data on antibiotic-resistant bacteria in the ward of a trauma center.     

A simple method for the control of medicinal leeches

The medicinal leech, Hirudo medicinalis, has been widely used in the salvage of microvascular free flaps. Numerous publications have detailed the biology, use, benefits, and risks of leech therapy. One reported significant risk is the risk of leech movement or migration from the surgical site, possibly into body orifices or even deeper into the wound itself. The authors report a simple method of limiting the movement of medicinal leeches from the surgical site, namely, affixing one end of a surgical suture to the leech and tying the free end to a firm object or dressing. This simple method limits the potential range of movement of the leech and reduces the risk of leech migration to unwanted areas.     

Aeromonas wound infection in burns

Infection of burn patients with the Aeromonas organism is an uncommon event. This paper documents four cases of Aeromonas hydrophila and one case involving both A. hydrophila and A. caviae occurring in burn patients between 1990 and 1998 at the Royal Brisbane Hospital burns unit. The organism was isolated from either skin swabs, tissue samples, blood cultures or cultured lines. In all patients there was a history of immersion in water immediately post burn. There is one case of invasion and destruction of deeper tissues and one fatality. Appropriate management requires a high index of suspicion if a history of immersion in untreated water post burn is given and the treatment involves aggressive excision and antibiotic therapy.     

The role of leech water sampling in choice of prophylactic antibiotics in medical leech therapy

Medical leech therapy (MLT) with Hirudo medicinalis is well established as a treatment for venous congestion of tissue flaps, grafts, and replants. Unfortunately, this treatment is associated with surgical site infections with bacterial species, most commonly Aeromonas hydrophila, which is an obligate symbiot of H. medicinalis. For this reason, prophylactic antibiotics are recommended in the setting of MLT. After culturing Aeromonashydrophila resistant to ciprofloxacin from a tissue specimen from a patient with a failed replant of three digits post‐MLT, we performed environmental surveillance cultures and antibiotic susceptibility testing on water collected from leech tanks. This surveillance was performed twice weekly for 2.5 months. Fourteen surveillance cultures demonstrated 21 isolates of Aeromonas species, 71.4% of which were ciprofloxacin susceptible. All isolates were sulfamethoxazole‐trimethoprim (SXT) susceptible. The prophylactic antibiotic regimen of choice for leech therapy at our institution is SXT, with culture of tank water to refine antimicrobial choice if necessary. This study demonstrates the importance of regular surveillance to detect resistant Aeromonas species in medical leeches; however optimal practice has not been established. © 2013 Wiley Periodicals, Inc. Microsurgery, 2013.     

普通外科ICU严重腹腔感染的病原菌分析与治疗体会

【摘要】〓目的〓探讨外科ICU严重腹腔感染患者的病原菌分布及耐药性,为临床经验用药提供参考依据。方法〓回顾性分析2012年1月~2013年12月58例严重腹腔感染患者的资料,对患者的病原学发布及耐药性进行分析。结果〓共分离出病原菌178株,其中革兰阴性杆菌126株,占70.79%,以大肠埃希菌为主;革兰阳性球菌39株,占20.79%,以屎肠球菌为主;真菌13株,占8.42%。大肠埃希菌和肺炎克雷伯菌产ESBLs菌株检出率分别为67.50%和57.25%,对碳青霉烯类抗菌药物耐药率低。初始病原菌分布以革兰阴性杆菌为主,第2、3周之后革兰阳性球菌分离率上升,真菌则多在第3周后出现。58例中混合病原菌感染占89.66%,细菌和真菌混合感染又占30.50%。未检出耐万古霉素肠球菌属。结论〓严重腹腔感染的病原菌以革兰阴性杆菌为主,混合感染的发生率及细菌的耐药率比较高,及早、合理的经验性抗感染治疗有利于控制细菌耐药的产生和播散。