Prophylactic Antibiotic Treatment Research Articles

Randomised controlled trial of prophylactic antibiotic treatment for the prevention of endophthalmitis after open globe injury at Groote Schuur Hospital

Background/aimsMost post-traumatic acute infectious endophthalmitis occur within a week of open globe trauma, necessitating early antibiotic prophylaxis. There are few randomised studies that demonstrate the benefits of prophylactic antibiotics. This...

Patient-Related Risk Factors for Postoperative Infection After Cholecystectomy

BackgroundThe impact of patient-related risk factors on the incidence of postoperative infection after cholecystectomy is relatively unknown.AimThe aim of this study was to explore potential patient-related risk factors for surgical site infection (SSI) and septicaemia following cholecystectomy.Materials and methodsAll cholecystectomies registered in the Swedish national population-based register for Gallstone Surgery and Endoscopic Retrograde Cholangiopancreatography (GallRiks) 2006–2014 were identified. The study cohort was cross-matched with the Swedish National Patient Register in order to obtain data on patient history and postoperative infections. Simple and multiple logistic regression analyses were performed in order to assess the impact of various comorbidities on the risk for SSI and septicaemia.ResultsA total of 94,557 procedures were registered. A SSI was seen following 5300 procedures (5.6%), and septicaemia following 661 procedures (0.7%). There was a significantly increased risk for SSI in patients with connective tissue disease (odds ratio [OR] 1.404, 95% confidence interval [CI] 1.208–1.633), complicated diabetes (OR 1.435, CI 1.205–1.708), uncomplicated diabetes (OR 1.391, CI 1.264–1.530), chronic kidney disease (OR 1.788, CI 1.458–2.192), cirrhosis (OR 1.764, CI 1.268–2.454) and obesity (OR 1.630, CI 1.475–1.802). There was a significantly higher risk for septicaemia in patients with chronic kidney disease (OR 3.065, CI 2.120–4.430) or cirrhosis (OR 5.016, CI 3.019–8.336).Conclusion and discussionCertain comorbidities have an impact on the risk for postoperative infection after cholecystectomy, especially SSI. This should be taken into account when planning the procedure and when deciding on prophylactic antibiotic treatment.

Propofol Sedation Exacerbates Kidney Pathology and Dissemination of Bacteria during Staphylococcus aureus Bloodstream Infections.

Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for large numbers of postsurgical nosocomial infections across the United States and worldwide. Propofol anesthesia is widely used in surgery and in intensive care units, and recent evidence indicates that even brief exposure to propofol can substantially increase host susceptibility to microbial infection. Here, we delineate the impact of propofol sedation on MRSA bloodstream infections in mice in the presence and absence of prophylactic antibiotic treatment. Consistent with previous reports, brief periods of anesthesia with propofol were sufficient to significantly increase bacterial burdens and kidney pathology in mice infected with MRSA. Propofol exposure increased neutrophilic infiltrates into the kidney and enhanced bacterial dissemination throughout kidney tissue. Propofol sedation reduced populations of effector phagocytes and mature dendritic cells within the kidney and led to the apparent expansion of myeloid-derived suppressor cell-like populations. When propofol was coadministered with vancomycin prophylaxis, it dramatically increased kidney abscess formation and bacterial dissemination throughout kidney tissue at early times post-S. aureus infection compared to antibiotic-treated but nonsedated animals. Taken together, our data indicate that short-term sedation with propofol significantly increases the severity of bloodstream MRSA infection, even when administered in conjunction with vancomycin prophylaxis.

Antimicrobial consumption, costs and resistance patterns: a two year prospective study in a Romanian intensive care unit

BackgroundDue to the vulnerable nature of its patients, the wide use of invasive devices and broad-spectrum antimicrobials used, the intensive care unit (ICU) is often called the epicentre of infections. In the present study, we quantified the burden of hospital acquired pathology in a Romanian university hospital ICU, represented by antimicrobial agents consumption, costs and local resistance patterns, in order to identify multimodal interventional strategies.MethodsBetween 1st January 2012 and 31st December 2013, a prospective study was conducted in the largest ICU of Western Romania. The study group was divided into four sub-samples: patients who only received prophylactic antibiotherapy, those with community-acquired infections, patients who developed hospital acquired infections and patients with community acquired infections complicated by hospital-acquired infections. The statistical analysis was performed using the EpiInfo version 3.5.4 and SPSS version 20.ResultsA total of 1596 subjects were enrolled in the study and the recorded consumption of antimicrobial agents was 1172.40 DDD/ 1000 patient-days.The presence of hospital acquired infections doubled the length of stay (6.70 days for patients with community-acquired infections versus 16.06/14.08 days for those with hospital-acquired infections), the number of antimicrobial treatment days (5.47 in sub-sample II versus 11.18/12.13 in sub-samples III/IV) and they increased by 4 times compared to uninfected patients. The perioperative prophylactic antibiotic treatment had an average length duration of 2.78 while the empirical antimicrobial therapy was 3.96 days in sample II and 4.75/4.85 days for the patients with hospital-acquired infections. The incidence density of resistant strains was 8.27/1000 patient-days for methicilin resistant Staphylococcus aureus, 7.88 for extended spectrum β-lactamase producing Klebsiella pneumoniae and 4.68/1000 patient-days for multidrug resistant Acinetobacter baumannii.ConclusionsSome of the most important circumstances collectively contributing to increasing the consumption of antimicrobials and high incidence densities of multidrug-resistant bacteria in the studied ICU, are represented by prolonged chemoprophylaxis and empirical treatment and also by not applying the definitive antimicrobial therapy, especially in patients with favourable evolution under empirical antibiotic treatment. The present data should represent convincing evidence for policy changes in the antibiotic therapy.

Risk factors for surgical site infections among 1,772 patients operated on for lumbar disc herniation: a multicentre observational registry-based study.

There are no previous studies evaluating risk factors for surgical site infections (SSIs) and the effectiveness of prophylactic antibiotic treatment (PAT), specifically for patients operated on for lumbar disc herniation. This observational multicentre study comprises a cohort of 1,772 consecutive patients operated on for lumbar disc herniation without laminectomy or fusion at 23 different surgical units in Norway. The patients were interviewed about SSIs according to a standardised questionnaire at 3 months' follow-up. Three months after surgery, 2.3% of the patients had an SSI. Only no PAT (OR = 5.3, 95% CI = 2.2-12.7, p< 0.001) and longer duration of surgery than the mean time (68 min) (OR = 2.8, 95% CI = 1.2-6.6, p = 0.02) were identified as independent risk factors for SSI. Numbers needed to have PAT to avoid one SSI was 43. In summary, this study clearly lends support to the use of PAT in surgery for lumbar disc herniation. Senior surgeons assisting inexperienced colleagues to avoid prolonged duration of surgery could also reduce the occurrence of SSI.

Transseptal suturing technique in septoplasty: impact on bacteremia and nosocomial colonization.

Although effects of Merocel® nasal packs and silicone splints on nasal flora alterations and bacteremia formation after septoplasty were assessed before, the effect of transseptal suturing technique has not been studied yet. The objective of this study is to compare nasal flora alterations and bacteremia occurrence rates between Merocel packs, silicone splints, and transseptal suturing technique in septoplasty. Ninety patients were divided into three groups randomly: Merocel packing (Group M), silicone splint (Group S), and transseptal suturing without packing (Group T). Group M and S received prophylactic antibiotics and antibiotic pomade application to packs, whereas neither antibiotic prophylaxis nor topical pomade was applied to Group T. Preoperative, after pack removal and 1month after pack removal nasal swab cultures and preoperative, immediately after surgery and 24h after surgery blood cultures were taken from all patients. Group M increased Methicillin-sensitive Staphylococcus aureus (MSSA) colonization (p = 0.003) and decreased normal flora colonization (p = 0.038), whereas Group S and T did not affect MSSA or normal flora colonization (p > 0.05). Antibiotic prophylaxis did not affect MSSA colonization (p = 0.14), whereas decreased normal flora colonization (p = 0.029). Transseptal suturing did not prevent bacteremia formation. Postoperative increasing of MSSA colonization in nasal cavity for septoplasty patients can be prevented by using transseptal suturing technique or silicone splints instead of Merocel packing, rather than applying prophylactic antibiotic treatment. Using transseptal suturing does not prevent bacteremia formation during septal surgery. These findings should be kept in mind to prevent postoperative life-threatening infective complications of septoplasty especially in immunosuppressive patients and patients with cardiovascular diseases.

Eye Injuries from Pencil Lead: Three Cases.

Corneal stromal and/or penetrating ocular injuries from pencils and pencil lead are more common in childhood and may lead to intraocular infection or severe intraocular sterile inflammatory reaction. Herein we report 3 children with ocular trauma due to pencil lead injuries. The first case had corneal stromal injury caused by a pencil. In the second case, a pencil perforated the cornea and contacted the iris. In the third case, pencil lead perforated both the cornea and iris and reached the vitreous through the lens zonules. Intracameral triamcinolone (2 mg/0.05 mL) was injected after the pencil lead was removed from the eyeball. Topical anti-inflammatory and cycloplegic drops were prescribed. In conclusion, corneal and especially penetrating ocular injuries from pencil lead may have a good prognosis with the use of appropriate anti-inflammatory and prophylactic antibiotic treatment and follow-up.

Clinical Features of Spontaneous Bacterial Peritonitis: A 10-year Experience from a Single Center.

Spontaneous bacterial peritonitis (SBP) is one of critical complications in liver cirrhosis patients with ascites. We aimed to review clinical course of SBP patients in a 10-year period from single center. This study enrolled SBP patients between 2005 and 2015. Their medical records were reviewed. The laboratory findings of serum and ascites were examined, and characteristics of isolated microorganisms in ascites were analyzed. Total 51 patients were enrolled. Male patients were predominant (64.7%), and mean age was 59.20 years. The most common etiology of cirrhosis was alcohol (41.2%), followed by hepatitis B (39.2%). Microorganism was isolated from the ascites in 31 patients (60.78%). The proportions of Gram negative and Gram positive were 80.64% and 19.36%. The proportions of Escherichia coli, Klebsiella, and Streptococcus species were 29.41%, 19.61% and 11.76%. Among Escherichia colis, 4 cases were ESBL positive (7.84%). The most commonly used first-line antibiotic was cefotaxime (80.40%). Prophylactic antibiotics treatment was performed only in 8 patients, and SBP was recurred in 7 patients (13.72%). When comparing the SBP recurrence group and the non-recurrence group, there were no significant differences in laboratory findings of serum and ascitic fluid. SBP is still a critical complication in cirrhosis patients with ascites, and the clinical features of SBP have not been altered much compared with those in 1990's. The effective treatment of SBP is still very important for a better prognosis of cirrhosis patients.

Selective Pressure Promotes Tetracycline Resistance of Chlamydia Suis in Fattening Pigs.

In pigs, Chlamydia suis has been associated with respiratory disease, diarrhea and conjunctivitis, but there is a high rate of inapparent C. suis infection found in the gastrointestinal tract of pigs. Tetracycline resistance in C. suis has been described in the USA, Italy, Switzerland, Belgium, Cyprus and Israel. Tetracyclines are commonly used in pig production due to their broad-spectrum activity and relatively low cost. The aim of this study was to isolate clinical C. suis samples in cell culture and to evaluate their antibiotic susceptibility in vitro under consideration of antibiotic treatment on herd level.Swab samples (n = 158) identified as C. suis originating from 24 farms were further processed for isolation, which was successful in 71% of attempts with a significantly higher success rate from fecal swabs compared to conjunctival swabs. The farms were divided into three treatment groups: A) farms without antibiotic treatment, B) farms with prophylactic oral antibiotic treatment of the whole herd consisting of trimethoprime, sulfadimidin and sulfathiazole (TSS), or C) farms giving herd treatment with chlortetracycline with or without tylosin and sulfadimidin (CTS). 59 isolates and their corresponding clinical samples were selected and tested for the presence or absence of the tetracycline resistance class C gene [tet(C)] by conventional PCR and isolates were further investigated for their antibiotic susceptibility in vitro. The phenotype of the investigated isolates was either classified as tetracycline sensitive (Minimum inhibitory concentration [MIC] < 2 μg/ml), intermediate (2 μg/ml ≤ MIC < 4 μg/ml) or resistant (MIC ≥ 4 μg/ml). Results of groups and individual pigs were correlated with antibiotic treatment and time of sampling (beginning/end of the fattening period). We found clear evidence for selective pressure as absence of antibiotics led to isolation of only tetracycline sensitive or intermediate strains whereas tetracycline treatment resulted in a greater number of tetracycline resistant isolates.

Surgical Treatment of Ankle Syndesmosis Injuries with Syndesmosis Elastic Hook.

Surgical Treatment of Ankle Syndesmosis Injuries with Syndesmosis Elastic Hook.

The Efficacy of Prophylactic Antibiotics on Post-Stroke Infections: An Updated Systematic Review and Meta-Analysis.

Post-stroke infections are common complications in acute stroke patients and are associated with an unfavorable functional outcome. However, reports on the effects of prophylactic antibiotics treatment on post-stroke infections are conflicting, especially those on post-stroke pneumonia and outcomes. We searched the PubMed, Embase, and Web of Knowledge databases up through March 11th, 2016. Seven randomized controlled trials including 4261 patients were analyzed among this systematic review and meta-analysis. We found preventive antibiotics treatment at the time of stroke onset did reduce the incidence of infections in adults with acute stroke (OR = 0.57, 95% CI: 0.38–0.85, P = 0.005), including reducing the number of urinary tract infections (OR = 0.34, 95% CI: 0.26–0.46, P < 0.001), but did not significantly decrease the rate of post-stroke pneumonia (OR = 0.91, 95% CI: 0.73–1.13, P = 0.385). Importantly, antibiotics treatment also showed no significant effect on the number of fatalities among stroke patients (OR = 1.07, 95% CI: 0.90–1.26, P = 0.743) and functional outcome scores on the modified Rankin Scale (OR = 1.76, 95% CI: 0.86–3.63, p = 0.124). Our study indicated that preventive antibiotics treatment not reduced the rate of post-stroke pneumonia or mortality, even though decreased the risk of infections, especially urinary tract infections. Thus, preventive antibiotics treatment may not be recommended for acute stroke patients.

Osteomyelitis following Domestic Animal Bites to the Hand: Two Case Reports and Practical Guidelines.

Recently, the number of cases of animal bite wounds has increased significantly in concordance with an increase in the pet population around the world. The authors report two rare cases of osteomyelitis of the phalanx following cat and dog bites. On initial physical examination, signs of a severe infection were observed. Radiographs of both patients showed the presence of osteomyelitis, and in one of the patients, the diagnosis was confirmed with a bone biopsy. After use of empirical antibiotics, intravenous antibiotic therapy that matched the identified bacterium's sensitivity was initiated, and at the same time, secure dressing including debridement was performed to induce secondary healing. In addition, the patients were closely monitored with serial X-rays, and culture and blood test follow-up. One patient fully recovered without sequelae, but the other patient suffered a loss of distal interphalangeal joint motion. When dealing with bite wounds located on the hand, it is important to visit the hospital as soon as possible and receive the appropriate treatment early. Moreover, to prevent severe complications such as osteomyelitis, it is important to administer antibiotic therapy to which the cultured bacteria are sensitive, along with proper wound management and prophylactic antibiotic treatment.

Bladder catheterization increases susceptibility to infection that can be prevented by prophylactic antibiotic treatment.

Catheter-associated urinary tract infections (CAUTI) are the most common hospital-associated infections. Here, we report that bladder catheterization initiated a persistent sterile inflammatory reaction within minutes of catheter implantation. Catheterization resulted in increased expression of genes associated with defense responses and cellular migration, with ensuing rapid and sustained innate immune cell infiltration into the bladder. Catheterization also resulted in hypersensitivity to Enterococcus faecalis and uropathogenic Escherichia coli (UPEC) infection, in which colonization was achieved using an inoculum 100-fold lower than the ID90 for infection of an undamaged urothelium with the same uropathogens. As the time of catheterization increased, however, colonization by the Gram-positive uropathogen E. faecalis was reduced, whereas catheterization created a sustained window of vulnerability to infection for Gram-negative UPEC over time. As CAUTI contributes to poorer patient outcomes and increased health care expenditures, we tested whether a single prophylactic antibiotic treatment, concurrent with catheterization, would prevent infection. We observed that antibiotic treatment protected against UPEC and E. faecalis bladder and catheter colonization as late as 6 hours after implantation. Thus, our study has revealed a simple, safe, and immediately employable intervention, with the potential to decrease one of the most costly hospital-incurred infections, thereby improving patient and health care economic outcome.

Formulation and Characterization of Nanocluster Ceftazidime for the Treatment of Acute Pulmonary Melioidosis

Melioidosis is an infectious disease caused by Burkholderia pseudomallei. The disease is responsible for a high proportion of human pneumonia and fatal bacteremia in the endemic areas of the world and is highly resistant to most commonly available antibiotics. Studies have shown that prophylactic antibiotic treatment, when administered 24 h following bacterial challenge, can prevent infection in a murine model. Prophylactic treatment against this disease using a pulmonary antibiotic formulation has not previously been examined, but may reduce the number of treatments required, allow for the delivery of higher doses, eliminate the need for intravenous administration, and help to minimize systemic side effects. Ceftazidime was formulated as a dry powder aerosol suitable for pulmonary delivery using previously developed NanoCluster dry powder technology. Pharmacokinetics of aerosolized ceftazidime was analyzed in a mouse model. This study demonstrates that ceftazidime can be formulated using NanoCluster technology as a dry powder aerosol suitable for pulmonary delivery to humans. We have also demonstrated the retention of nebulized ceftazidime in mouse lungs for up to 6 h after exposure. The results indicate that this treatment may be useful as a prophylactic treatment against melioidosis. Future work will examine the efficacy of this treatment against B. pseudomallei aerosol challenge.

A “Shark Encounter”: Delayed Primary Closure and Prophylactic Antibiotic Treatment of a Great White Shark Bite

BackgroundShark bites are rare but sensational injuries that are covered in the lay press but are not well described in the medical literature. Case ReportWe present the case of a 50-year-old man who sustained two deep puncture wounds to his thigh from a great white shark in the waters surrounding Isla de Guadalupe off the coast of Baja California, Mexico, during a caged SCUBA dive. Why Should An Emergency Physician be Aware of This?We discuss our strategy of closing the wounds in a delayed primary fashion 24 hours after injury, our antibiotic choices, and the patient's course and review marine pathogens and appropriate antibiotic coverage.

Prophylactic antibiotic treatment in severe acute ischemic stroke: the Antimicrobial chemopRrophylaxis for Ischemic STrokE In MaceDonIa-Thrace Study (ARISTEIDIS).

Infections represent a leading cause of mortality in patients with acute ischemic stroke, but it is unclear whether prophylactic antibiotic treatment improves the outcome. We aimed to evaluate the effects of this treatment on infection incidence and short-term mortality. This was a pragmatic, prospective multicenter real-world analysis of previously independent consecutive patients with acute ischemic stroke who were >18years, and who had at admission National Institutes of Health Stroke Scale (NIHSS) >11. Patients with infection at admission or during the preceding month, with axillary temperature at admission >37°C, with chronic inflammatory diseases or under treatment with corticosteroids were excluded from the study. Among 110 patients (44.5% males, 80.2±6.8years), 31 (28.2%) received prophylactic antibiotic treatment, mostly cefuroxime (n=21). Prophylactic antibiotic treatment was administered to 51.4% of patients who developed infection, and to 16.4% of patients who did not (p<0.001). Independent predictors of infection were NIHSS at admission [relative risk (RR) 1.16, 95% confidence interval (CI) 1.08-1.26, p<0.001] and prophylactic antibiotic treatment (RR 5.84, 95% CI 2.03-16.79, p<0.001). The proportion of patients who received prophylactic antibiotic treatment did not differ between patients who died during hospitalization and those discharged, or between patients who died during hospitalization or during follow-up and those who were alive 3months after discharge. Prophylactic administration of antibiotics in patients with severe acute ischemic stroke is associated with an increased risk of infection during hospitalization, and does not affect short-term mortality risk.

Controlled Delivery of Vancomycin via Charged Hydrogels.

Surgical site infection (SSI) remains a significant risk for any clean orthopedic surgical procedure. Complications resulting from an SSI often require a second surgery and lengthen patient recovery time. The efficacy of antimicrobial agents delivered to combat SSI is diminished by systemic toxicity, bacterial resistance, and patient compliance to dosing schedules. We submit that development of localized, controlled release formulations for antimicrobial compounds would improve the effectiveness of prophylactic surgical wound antibiotic treatment while decreasing systemic side effects. Our research group developed and characterized oligo(poly(ethylene glycol)fumarate) / sodium methacrylate (OPF/SMA) charged copolymers as biocompatible hydrogel matrices. Here, we report the engineering of this copolymer for use as an antibiotic delivery vehicle in surgical applications. We demonstrate that these hydrogels can be efficiently loaded with vancomycin (over 500 μg drug per mg hydrogel) and this loading mechanism is both time- and charge-dependent. Vancomycin release kinetics are shown to be dependent on copolymer negative charge. In the first 6 hours, we achieved as low as 33.7% release. In the first 24 hours, under 80% of total loaded drug was released. Further, vancomycin release from this system can be extended past four days. Finally, we show that the antimicrobial activity of released vancomycin is equivalent to stock vancomycin in inhibiting the growth of colonies of a clinically derived strain of methicillin-resistant Staphylococcus aureus. In summary, our work demonstrates that OPF/SMA hydrogels are appropriate candidates to deliver local antibiotic therapy for prophylaxis of surgical site infection.

Soft tissue infections due to human bites

Background: Human bites are potentially dangerous wounds constituting an important cause of morbidity. Infections caused by human bites are reported to be more severe than infections caused by animal bites. The aim of this article is to present two patients with soft tissue infections secondary to human bites, which are rare in the literature. Case presentation: The first patient is a 62-year old female whose 4 th digit of her left hand was bitten by her disabled child and became necrotic. The second patient is a 35-year old female patient whose 2 nd digit in her left hand was bitten by her husband five days ago. Both patients had undergone debridement for the necrotic infections in the area of the lesion and prescribed the appropriate antibiotherapy. Rest, elevation and immobilization were maintained. The reconstruction and physiotherapy gave satisfactory results. Conclusion: Human bite wounds have long had a bad reputation for severe infection and frequent complication. For this reason, prophylactic antibiotic treatment should be given after human bite to prevent infection. If the infection signs and symptoms develop, rapid diagnosis, appropriate antibiotic and surgical therapy should be applied instantly.

Risk Factors for Periprosthetic Joint Infections Following Primary Total Hip Arthroplasty

Total hip arthroplasty (THA) is a very successful and effective operation for the restoration of the hip function. The number of operations is steadily climbing and is going to reach new heights in the future. The most feared and devastating complication is the periprosthetic joint infection (PJI) and has in most cases to be treated with a total revision of the prostheses. The risk factors for a PJI are playing a very important role in the preoperative assessment of the patient and for the type of antibiotic treatment. There are many risk factors described in the literature, which are associated with the development of a PJI. Our goal was to analyze and find the relevant risk factors, which matter most in joint replacement surgery. We searched the database PubMed and Embase with the keywords: ((hip AND infection) AND (arthroplasty OR replacement)). With the help of check lists and limits we extracted the most viable studies for our research. Risk factors associated with a deep periprosthetic joint infection included the BMI (Body mass index), male gender, prolonged duration of surgery, diabetes mellitus type 2, the ASA (American society of anesthesiologists) score, the Charlson score and the NNIS (National Nosocomial Infections Surveillance System) risk index score. Female gender, age and the diagnosis of rheumatoid arthritis were not associated with a higher risk of periprosthetic joint infections. Patients with risk factors should be assessed and informed preoperatively and should receive an appropriate prophylactic antibiotic treatment, to reduce the risk of a PJI. With the reduction of their weight and adjustment of the diabetes, patients can reduce the risk for PJI by their own. Total hip replacement is still a very safe and effective operation and therefore should not be withheld from patients.

Long-Term Prophylactic Antibiotic Treatment: Effects on Survival, Immunocompetence and Reproduction Success of Parasemia plantaginis (Lepidoptera: Erebidae).

Hundreds of insect species are nowadays reared under laboratory conditions. Rearing of insects always implicates the risk of diseases, among which microbial infections are the most frequent and difficult problems. Although there are effective prophylactic treatments, the side effects of applied antibiotics are not well understood. We examined the effect of prophylactic antibiotic treatment on the overwintering success of wood tiger moth (Parasemia plantaginis) larvae, and the postdiapause effect on their life-history traits. Four weeks before hibernation larvae were treated with a widely used antibiotic (fumagillin). We monitored moths’ survival and life-history traits during the following 10 mo, and compared them to those of untreated control larvae. Prophylactic antibiotic treatment had no effect on survival but we show effects on some life-history traits by decreasing the developmental time of treated larvae. However, we also revealed relevant negative effects, as antibiotic treated individuals show a decreased number of laid eggs and also furthermore a suppressed immunocompetence. These results implicate, that a prophylactic medication can also lead to negative effects on life-history traits and reproductive success, which should be seriously taken in consideration when applying a prophylactic treatment to laboratory reared insect populations.