Gentamicin as Empirical Treatment in Hemodialysis Patients: Safety, Pharmacokinetics, and Pharmacodynamics.

The aim of this study was to describe the safety profile and pharmacokinetic/pharmacodynamic parameters in end-stage renal disease patients who received gentamicin as empirical treatment in catheter-related bacteremia when they showed infection signs, regardless of the timing of the next HD. Patients received gentamicin 3 mg/kg before blood culture extraction when they showed infection signs and regardless of the timing of next hemodialysis session. Serum concentrations were collected after the gentamicin administration (peak level) and before the next HD (trough level). Toxicities and adverse drug events were registered. The main pharmacokinetic/pharmacodynamic goal for Gram-negative infections was peak:minimum inhibitory concentration (MIC) ≥10. Sixteen patients were included. Nephrotoxicity was not assessed in this population, and no ototoxicity was found. According to microbial isolation and gentamicin susceptibility, the value of peak:MIC was 5.4 ± 2.0. The administration of gentamicin in these conditions was safe. Estimated pharmacokinetic values were consistent with previous studies and appropriate according to peak:MIC goal for Gram-negative organisms with MIC ≤1 mg/L.

Role of Negative Pressure Wound Care and Hyperbaric Oxygen Therapy for Sternal Wound Infections After Pediatric Cardiac Surgery.

BACKGROUND: Sternal wound infections after pediatric cardiac surgery are uncommon but can be morbid. METHODS: We describe an institutional protocol for complicated sternal wounds utilizing hyperbaric oxygen therapy (HBO) and negative pressure wound therapy (NPWT). PARTICIPANTS: A retrospective chart review (2001-2013) of 4,028 pediatric cardiac operations in 3,264 patients less than 18 years of age. RESULTS: Fifty-three patients (1.62%; 53/3,264) were diagnosed with clinical sternal wound infections. There were 27 (50.9%) males and 26 (49.1%) females. Thirty-seven (69.8%) patients received antibiotics and/or debridement; sixteen (30.2%) patients had more complicated infections requiring NPWT and/or HBO therapy. The time to heal for wounds treated with HBO and HBO + NPWT was a mean of 43.75 (±24.27) days (range: 21-98 days; median: 35 days). Among all infected patients, the time from diagnosis of the infection to resolution of the infection for all survivors was 7 to 98 days (mean: 26.41 days; median: 21 days). Forty-eight (90.6%) patients completely healed their wounds, and 45 (84.9%) patients are currently alive. Thirty-eight patients had a cyanotic cardiac diagnosis and 15 had an acyanotic cardiac diagnosis. The most common bacteria isolated from the blood or wound cultures was Staphylococcus aureus. Six of 53 patients died. Causes of death are as follows: three from respiratory failure, one from sepsis, one from hypoxic ischemic encephalopathy, and one from exsanguination leading to cardiac arrest Conclusions: Complicated sternal wound infections after pediatric cardiac surgery refractory to antibiotic therapy and/or debridement can be successfully treated with NPWT and/or HBO therapy.

Ceftriaxone-Resistant Aeromonas hydrophila Infection Following Leech Therapy: A New Resistant Strain.

We report a case of ceftriaxone-resistant Aeromonas hydrophila infection in a 32-year-old man after medicinal leech therapy. The patient underwent a free gracilis muscle flap for dorsal foot soft tissue reconstruction. Because of persistent congestion after venous revision, medicinal leech therapy was initiated to aid in flap salvage. Intravenous ceftriaxone was administered prior to application of leeches for prophylaxis against A. hydrophila. Leech therapy was discontinued after 1 week, and ceftriaxone was discontinued 24 hours thereafter. An infection developed despite being on appropriate antibiotics. Culture sensitivities indicated that A. hydrophila was resistant to ceftriaxone.

In Vitro and In Vivo Control of Secondary Bacterial Infection Caused by Leishmania major.

Bacterial infections of cutaneous leishmaniasis cause skin ulcers on mice, resulting in increased tissue deterioration, and these infections can be controlled with liquid allicin. To isolate and identify the incidences of real secondary bacterial infections in mice, we performed the current study by injecting mice (n = 50) with Leishmania major. L. major infections were initiated by an intramuscular injection of 0.1 mL Roswell Park Memorial Institute (RPMI 1640 media/mouse (107 promastigote/mL)). Scarring appeared 2-6 weeks after injection, and the bacteria were isolated from the skin ulcer tissues. Allicin (50 µL/mL) and ciprofloxacin (5 µg; Cip 5) were used for controlling L. major and bacteria. One hundred samples from skin ulcers of mice were examined, and 200 bacterial colonies were isolated. Forty-eight different genera and species were obtained and identified by Gram staining and physiological and biochemical characterization using identification kits. All samples were positive for secondary bacterial infections. Of the isolates, 79.16% were identified as Gram-negative bacteria, and 28.84% were identified as Gram-positive bacteria; only one yeast species was found. Interestingly, pure allicin liquid at a concentration 50 µL/mL exhibited antibacterial activity against a wide range of Gram-negative and some Gram-positive bacteria, in addition to yeast, and was 71.43% effective. Antimicrobial resistance patterns of all genera and species were determined using 15 different antibiotics. Allicin (50 µL/mL) and Cip 5 were the most effective against L. major and 92.30% of isolated bacteria. Stenotrophomonas maltophilia was the most resistant bacterium to the tested antibiotics with a survival rate of 73.33%, and it exhibited resistance to allicin.

Medicinal leech therapy and Aeromonas spp. infection.

While the use of medicinal leech therapy (MLT) in reconstructive and orthopaedic surgery is widely described, post-operative complications related to leeches remain a major concern. Aeromonas spp. strains are involved in the majority of reported cases. As surgical success rate is directly impacted, an adapted antibiotic prophylaxis should be instituted in order to minimize these complications. We assessed pharmaceutical process, microbiological control and related infections in order to provide data and choose the appropriate antibiotherapy for patients requiring MLT. We report a clinical and microbiological study over a 24-month period. Clinical data were collected from patients' database, and microbiological analysis both on leeches' tank water and crushed leeches were performed to characterize isolated strains and their susceptibility to antibiotics. A total of 595 leeches were used to treat 28 patients (12 in plastic surgery and 16 in orthopaedic surgery), and three documented cases of post-operative infections were reported. Aeromonas spp. isolates yielded from 62 % of analyzed batches (75 % of Aeromonas veronii). Eighteen Aeromonas spp. isolates yielded from 23 water samples and three crushed leeches. Isolates were similar in tank and crushed leeches. Strains were susceptible to fluoroquinolones, sulfamethoxazole/trimethoprim, aminosides, and third-generation cephalosporins but resistant to amoxicillin/clavulanic acid and second-generation cephalosporins. According to collected data, routine tank water microbiological analyses are mandatory in order to identify leeches' batches containing resistant strains and to discard them. In this context, the surgeon is able to select an appropriated antibiotic prophylaxis in order to avoid MLT associated serious post-operative complications.

Bacteria causing ventriculoperitoneal shunt infections in a Kenyan population.

OBJECT: Ventriculoperitoneal shunt (VPS) infections are a major cause of morbidity and mortality in patients with hydrocephalus. Most data about these infections come from the Western literature. Few data about infecting organisms in Africa are available, yet knowledge of these organisms is important for the prevention and treatment of infectious complications. The purpose of this study was to determine the organisms cultured from infected shunts in a rural Kenyan hospital. METHODS: The authors conducted a retrospective study of patients with VPS infections recorded in the neurosurgical database of BethanyKids at Kijabe Hospital between September 2010 and July 2012. RESULTS: Among 53 VPS infections confirmed by culture, 68% occurred in patients who were younger than 6 months. Seventy-nine percent of the infections occurred within 2 months after shunt insertion. Only 51% of infections were caused by Staphylococcus species (Staphylococcus aureus 25%, other Staphylococcus species 26%), whereas 40% were caused by gram-negative bacteria. All S. aureus infections and 79% of other Staphylococcus infections were sensitive to cefazolin, but only 1 of 21 gram-negative bacteria was sensitive to it. The majority of gram-negative bacterial infections were multidrug resistant, but 17 of the 20 gram-negative bacteria were sensitive to meropenem. Gram-negative bacterial infections were associated with worse outcomes. CONCLUSIONS: The high proportion of gram-negative infections differs from data in the Western literature, in which Staphylococcus epidermidis is by far the most common organism. Once a patient is diagnosed with a VPS infection in Kenya, immediate treatment is recommended to cover both gram-positive and gram-negative bacterial infections. Data from other Sub-Saharan countries are needed to determine if those countries have the same increased frequency of gram-negative infections.

In vitro efficacy of high-dose tobramycin against Burkholderia cepacia complex and Stenotrophomonas maltophilia isolates from cystic fibrosis patients.

Burkholderia cepacia complex and Stenotrophomonas maltophilia infections are associated with poor clinical outcomes in persons with cystic fibrosis (CF). The MIC50 based on planktonic growth and the biofilm concentration at which 50% of the isolates tested are inhibited (BIC50) of tobramycin were measured for 180 B. cepacia complex and 101 S. maltophilia CF isolates and were 100 µg/ml for both species. New inhalation devices that deliver high tobramycin levels to the lung may be able to exceed these MICs.

Reorganization of nutritional therapy can markedly reduce the rate of catheter-related blood stream infections in pediatric patients receiving parenteral nutrition - a 7-year prospective follow-up study.

BACKGROUND: Implementation of hygienic measures and simple changes in the structure of medical team may considerably reduce the rate of catheter-related bloodstream infections (CRBSIs) in parenterally nourished patients. AIM: To analyze the effects of organizational changes in parenteral nutrition services on the CRBSI rates in pediatric patients. METHODS: We compared the CRBSI rates documented prior to, during and after the implementation of the organizational changes (introduction of a nutritional support team and related procedures, medical staff training). FINDINGS: A total of 260 courses of parenteral nutrition were offered to 141 pediatric patients during the analyzed period. Thirty CRBSIs were documented during this period. The most frequent etiological factors were staphylococci (21/30), followed by Klebsiella pneumoniae, Escherichia coli and Candida albicans (2/30 each). The reorganization was reflected by more than 8-fold reduction of the CRBSI incidence rate: from the initial value of 10.14 to 6.89 per 1000 catheter days and 1.17 per 1000 catheter days during and after the reorganization, respectively. CONCLUSION: Introduction of a nutritional support team, accompanied by extensive training of medical staff, can result in a marked reduction of CRBSI rate in pediatric patients nourished parenterally in a hospital setting.

Antecedentes: La implementación de medidas higiénicas y cambios sencillos en la estructura del personal médico puede reducir considerablemente la tasa de bacteriemia asociada al catéter (BAC) en pacientes que reciben nutrición parenteral. Objetivo: Analizar el impacto de los cambios organizacionales dentro de los servicios de nutrición parenteral sobre las tasas de BAC en pacientes pediátricos. Métodos: Hemos comparado las tasas de BAC documentadas antes, durante y después de la implementación de los cambios organizacionales (introducción de un grupo de apoyo nutricional y los procedimientos relacionados, formación del personal médico). Descubrimientos: Un total de 260 series de nutrición parenteral fueron ofrecidos a 141 pacientes pediátricos durante el periodo analizado. Se documentaron treinta BAC durante este periodo. Los factores etiológicos más frecuentes eran staphylococci (21/30), seguidos por Klebsiella pneumoniae, Escherichia coli y Candida albicans (2/30 cada uno). Los cambios organizacionales fueron reflejados en una reducción de la incidencia de BAC en más de 8 veces: el valor inicial disminuyó desde 10.14 hasta 6.89 por 1000 días-catéter y hasta 1.17 por 1000 días-catéter durante y después de la reorganización, respectivamente. Conclusión: La introducción de un grupo de apoyo nutricional, acompañada de una extensa formación del personal médico puede resultar en una reducción considera ble de la tasa de BAC en pacientes pediátricos que reciben nutrición parenteral en en un entorno hospitalario.

Clinical characteristics of Stenotrophomonas maltophilia meningitis in adults: a high incidence in patients with a postneurosurgical state, long hospital staying and antibiotic use.

OBJECTIVE: Stenotrophomonas (S.) maltophilia is an uncommon pathogen of adult bacterial meningitis (ABM). METHODS: The clinical characteristics of six S. maltophilia ABM cases, collected during a study period of nine years (2001-2009) were included. In the related literature, 13 S. maltophilia ABM cases were reported, and their clinical data were also collected. RESULTS: The 19 S. maltophilia ABM cases included 11 men and 8 women, aged 28-70 years. Of these 19 cases, 89.5% (17/19) had underlying neurosurgical (NS) conditions as the preceding event. Before the development of S. maltophilia ABM, 52.6% (10/19) of them had long stays in hospital and 63.2% (12/19) had undergone antibiotic treatment. Among the implicated S. maltophilia cases, three strains were found to have a resistance to sulfamethoxazole-trimethoprim (SMZ-TMP). Two of our five cases had resistant strains to levofloxacin. Among the antibiotics chosen for treatment, SMZ-TMP was the most common followed by quinolone (ciprofloxacin, levofloxacin, moxifloxacin). The therapeutic results showed 2 cases expired while the other 17 cases survived. CONCLUSIONS: S. maltophilia ABM usually develops in patients with a preceding neurosurgical condition, a long hospital stay and antibiotic use. SMZ-TMP and quinolones, especially the ciprofloxacin, are the major antibiotic used. This study also shows the emergence of clinical S. maltophilia strains which are not susceptible to SMZ-TMP and quinolones and this development may pose a more serious threat in the near future because treatment options may become depleted and limited despite the mortality rate of this specific group of ABM not being high at this time.

Flap infection associated with medicinal leeches in reconstructive surgery: two new drug-resistant organisms.

The use of medicinal leeches in reconstructive surgery has proven value for the salvage of flaps with venous congestion but is associated with a risk of leech-acquired infection. The most common leech-associated organism is Aeromonas hydrophila, which antibiotic prophylaxis is typically directed against. The authors describe two new multidrug-resistant organisms acquired from medicinal leech therapy that resulted in flap infection. The evaluation of suspected leech-borne infection and management protocol for this leech-acquired resistant multi-organism infection is presented.

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.

Ultraviolet-C irradiation for prevention of central venous catheter-related infections: an in vitro study.

Central venous catheters (CVC) are widely used in the United States and are associated with 250,000 to 500,000 CVC-related infections in hospitals annually. We used a catheter made from ultraviolet-C (UVC) transmissive material to test whether delivery of UVC from the lumen would allow inactivation of microorganisms on the outer surface of CVC. When the catheter was exposed to UVC irradiation from a cold cathode fluorescent lamp inside the catheter lumen at a radiant exposure of 3.6 mJ cm(-2) , more than 6-log(10) of drug-resistant Gram-positive bacteria adhered to the outer surface of the catheter were inactivated. Three to 7-log(10) of drug-resistant Gram-negative bacteria and 2.80-log(10) of fungi were inactivated at a radiant exposure of 11 mJ cm(-2).UVC irradiation also offered a highly selective inactivation of bacteria over keratinocytes under exactly comparable conditions. After 11 mJ cm(-2) UVC light had been delivered, over 6-log(10) of bacteria were inactivated while the viability loss of the keratinocytes was only about 57%.

Acute postoperative infection with Aeromonas hydrophila after using medical leeches for treatment of venous congestion.

INTRODUCTION: Venous convulsion after reconstructive microsurgery procedures is one major complication a surgeon has to deal with. Today, especially in the field of reconstructive microsurgery, medicinal leech therapy enjoys a renaissance. The potential risks such as infections associated with leech therapy are generally underestimated and not sufficiently discussed in literature. METHOD/PATIENTS: We present five male patients with an average age of 47 years. All patients suffered from a trauma incident, which had to be treated as an emergency. Three patients showed, postoperatively, a venous congestion after the reconstructive procedures. Another two patients with flap reconstruction and flap training developed venous problems after 12 and 14 days. In all five cases, the indication was given to use medical leeches (Hirudo medicinalis). In all the patients, a local infection of the injured extremity could be regarded after beginning with the leech treatment. The treatment duration with medical leeches for postoperative venous congestion was an average of 6 days. RESULTS: The reconstructive procedures in all five cases were unfortunately unsuccessful as major local infections were observed. Microbiological analyses showed, in all cases, an infection with Aeromonas hydrophila. CONCLUSION: We recommend making a considered indication for leech therapy, to diagnose wound infections early and to think about prophylactic antibiotics in patients with leech application.

Aeromonas septicemia after medicinal leech use following replantation of severed digits.

Medicinal leeches are used to control venous congestion. Aeromonas in the leech gut are essential for digestion of blood. This case report describes a patient who had Aeromonas bacteremia develop after leeching. He had an injury to his hand that required replantation of his thumb. Following the surgery, leech therapy was started with ampicillin-sulbactam prophylaxis. Sepsis developed. Blood cultures were positive for Aeromonas that were resistant to ampicillin-sulbactam. The antibiotic was changed to ciprofloxacin on the basis of the sensitivity profile of the organisms. Cultures from the leech bathwater confirmed it as the source of the Aeromonas. Clinicians who use leech therapy must be aware that leeches can harbor Aeromonas species resistant to accepted prophylactic antibiotics and that sepsis may occur.

Aeromonas hydrophila ecthyma gangrenosum without bacteraemia in a diabetic man: the first case report in Italy.

Ecthyma gangrenosum is a well recognized cutaneous manifestation of severe, invasive infection by Pseudomonas aeruginosa usually in immunocompromised and critically ill patients. This type of infection is usually fatal. Aeromonas infection is infrequently reported as the cause of ecthyma gangrenosum. Here we show the first case described in Italy of Aeromonas hydrophila ecthyma gangrenosum in the lower extremities in an immunocompetent diabetic without bacteraemia. A 63-year-old obese diabetic male was admitted with an ulcer on his left leg, oedema, pain and fever. Throughout his hospitalization blood cultures remained sterile, but a culture of A. hydrophila was isolated following punctures from typical leg pseudomonal-ecthyma gangrenosum lesions developed after admission. The patient, questioned again, stated that a few days before he had worked in a well near his house without taking precautions. We conclude that early diagnosis and suitable antibiotic therapy are important for the management of ecthyma gangrenosum. The typical presentation of soft tissue infection of A. hydrophila should mimic a Gram-positive infection, which may result in a delay in administration of appropriate antibiotics. Moreover, A. hydrophila should be considered a possible agent for non-pseudomonal ecthyma gangrenosum in a diabetic man with negative blood cultures, in presence of anamnestical risk factors.