The clinical profile and outcomes of adult patients given intravenous colistin for multidrug-resistant gram negative infections in a Philippine tertiary hospital

The Challenge of Bacteremia Treatment due to Non-Fermenting Gram-Negative Bacteria

Nosocomial infections caused by non-fermenting Gram-negative bacteria are a real challenge for clinicians, especially concerning the accuracy of empirical treatment. This study aimed to describe the clinical characteristic, empirical antibiotic therapy, accuracy of these prescriptions for appropriate coverage and risk factor for clinical failure of bloodstream infections due to non-fermenting Gram-negative bacilli. This retrospective, observational cohort study was conducted between January 2016 and June 2022. Data were collected from the hospital’s electronic record. The statistic tests corresponding to each objective were applied. A multivariate logistic regression was performed. Among the total 120 patients included in the study, the median age was 63.7 years, and 79.2% were men. Considering the appropriate empirical treatment rate by species, inappropriate treatment for S. maltophilia was 72.4% (p = 0.088), for A. baumanii 67.6% and 45.6% for P. aeruginosa. Clinical success was achieved in 53.3%, and overall, 28-day mortality was 45.8%. ICU admission, sepsis or shock septic, age, previous antibiotic treatment and contact with healthcare facilities were independently associated with clinical failure. In conclusion, bloodstream infection produced by multidrug-resistant non-fermenting Gram-negative bacteria is a significant therapeutic management challenge for clinicians. The accuracy of empirical treatment is low due to the fact that it is not recommended to cover these microorganisms empirically, especially S. maltophilia and A. baumanii.

Prevalence of polymyxin-induced nephrotoxicity and its predictors in critically ill adult patients: A meta-analysis

BACKGROUND

Polymyxin-induced nephrotoxicity is a major safety concern in clinical practice due to long-term adverse outcomes and high mortality.

AIM

To conducted a systematic review and meta-analysis of the prevalence and potential predictors of polymyxin-induced nephrotoxicity in adult intensive care unit (ICU) patients.

METHODS

PubMed, EMBASE, the Cochrane Library and Reference Citation Analysis database were searched for relevant studies from inception through May 30, 2022. The pooled prevalence of polymyxin-induced nephrotoxicity and pooled risk ratios of associated factors were analysed using a random-effects or fixed-effects model by Stata SE ver. 12.1. Additionally, subgroup analyses and meta-regression were conducted to assess heterogeneity.

RESULTS

A total of 89 studies involving 12234 critically ill adult patients were included in the meta-analysis. The overall pooled incidence of polymyxin-induced nephrotoxicity was 34.8%. The pooled prevalence of colistin-induced nephrotoxicity was not higher than that of polymyxin B (PMB)-induced nephrotoxicity. The subgroup analyses showed that nephrotoxicity was significantly associated with dosing interval, nephrotoxicity criteria, age, publication year, study quality and sample size, which were confirmed in the univariable meta-regression analysis. Nephrotoxicity was significantly increased when the total daily dose was divided into 2 doses but not 3 or 4 doses. Furthermore, older age, the presence of sepsis or septic shock, hypoalbuminemia, and concomitant vancomycin or vasopressor use were independent risk factors for polymyxin-induced nephrotoxicity, while an elevated baseline glomerular filtration rate was a protective factor against colistin-induced nephrotoxicity.

CONCLUSION

Our findings indicated that the incidence of polymyxin-induced nephrotoxicity among ICU patients was high. It emphasizes the importance of additional efforts to manage ICU patients receiving polymyxins to decrease the risk of adverse outcomes.

The Spectrum of Manifestations of Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS-CoV2) Infection in Children: What We Can Learn From Multisystem Inflammatory Syndrome in Children (MIS-C)

Multisystem Inflammatory Syndrome in Children (MIS-C) is defined as a clinically serious condition requiring hospitalization with fever, multi-system organ disfunction, inflammatory biomarkers increase. The syndrome develops in the context of a probable or ascertained Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV2) infection, but other possible etiologies should be ruled out for definitive diagnosis. On the clinical side, along with the multi-system involvement, myocarditis with heart failure and shock is the most striking feature. Capillary leak is another fundamental feature of MIS-C. In fact, shock and hemodynamic compromise in MIS-C can occur also in the absence of laboratory evidence of myocardial inflammation, with preserved cardiac function and rapid reversibility. Since the first observations of MIS-C patients, it was evident that there is a delay between the peak of adult cases of Coronavirus disease 19 (COVID-19) and the MIS-C peak. Moreover, SARS-Cov2 isolation in children with MIS-C is not always possible, due to low viral load, while positive serology is far more commonly observed. These observations lead to the interpretation of MIS-C as a post-infectious disease. Although the exact pathogenesis of MIS-C is far from being elucidated, it is clear that it is a hyperinflammatory disease with a different inflammatory response as compared to what is seen in acute SARS-CoV-2 infection and that the disease shares some, but not all, immunological features with Macrophage Activation Syndrome (MAS), Kawasaki Disease (KD), Hemophagocytic Lymphohistiocytosis (HLH), and Toxic Shock Syndrome (TSS). Different mechanisms have been hypothesized as being responsible, from molecular mimicry to antibody dependent enhancement (ADE). Some evidence has also been collected on the immunological profile of patients with MIS-C and their difference from COVID-19. This review is focused on critical aspects of MIS-C clinical presentation and pathogenesis, and different immunological profiles. We propose a model where this hyperinflammatory disease represents one manifestation of the SARS-CoV2 spectrum in children, going from asymptomatic carriers to the post-infectious MIS-C, through symptomatic children, a low number of which may suffer from a severe infection with hyperinflammation (pediatric Hyper-COVID).

Prevalence of β-lactamase-encoding genes and molecular typing of Acinetobacter baumannii isolates carrying carbapenemase OXA-24 in children

Background

β-Lactam antibiotics have been broadly used for the treatment of Acinetobacter baumannii infections, resulting in development of β-lactam inactivating β-lactamases. Here, we described antibiotic resistance rate, prevalence of β-lactamase-encoding genes, and clonal relationships of A. baumannii strains isolated from children referred to Children’s Medical Center in Tehran, Iran, during 2019–2020.

Methods

A total of 60 non-replicate A. baumannii isolates were recovered from clinical specimens of pediatric patients. Antibiotic susceptibility testing was done by the disc diffusion method. Colistin susceptibility of isolates was performed by the broth microdilution method. β-lactamase-encoding genes were characterized by PCR. The presence of ISAba1 element upstream of the several oxacillinase genes was also checked. Genetic relatedness of isolates was determined by using random amplification of polymorphic DNA (RAPD) typing.

Results

The antimicrobial susceptibility tests showed that 83.3% of A. baumannii isolates were MDR, and 40% XDR. Both MDR and XDR A. baumannii isolates were susceptible to colistin. The frequency of bla_OXA-51-like, bla_OXA-23-like, bla_TEM, bla_OXA-24-like, bla_PER, bla_SHV, bla_CTX-M, bla_OXA-58-like, and bla_IMP was 100, 93.33, 60, 36.67, 28.33, 8.33, 5, 3.33, and 1.67%, respectively. Coexistence of ISAba1/bla_OXA-23-like and ISAba1/bla_OXA-51-like was observed in 65% and 85% of isolates, respectively. RAPD analysis revealed 4 common types and 2 single types of A. baumannii isolates.

Conclusions

The multiple clones harboring bla_OXA-23-like, ISAba1-bla_OXA-51-like, and ISAba1-bla_OXA-23-like were responsible for the spread of A. baumannii isolates in our clinical wards. Dissemination of the well-established clones is worrisome and would become therapeutic challenges due to the possible transferring genetic elements associated with resistance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12941-021-00480-5.

Intravenous colistin in the treatment of multidrug-resistant gram-negative organism in tertiary hospital, Jazan, KSA

Background

It was considered that the resistance of drugs such as carbapenems and cephalosporins against severe or high risk gram-negative bacteria became a tremendous confront. This might be attributed to the little amount of these drugs to be used against the multi-resistant bacteria (MRB). Therefore, Colistin, Fosfomycin, Temocillin, and Rifampicin are antibiotics that have been used as multidrug-resistant bacterial infections in the treatment of some species of bacteria such as Acinetobacter, Pseudomonas species, and Enterobacteriaceae.

Aim

the present study is aimed to assess the integrity and efficiency of colistin for treating of the multidrug-resistant bacteria (MDR) especially gram-negative one among critical and non-critical patients in tertiary hospital in Jazan city. Ninety four patients who met the selection criteria and received colistimethate sodium (colistin) in the period between Februarys 2017 and March 2018 were recruited and their charts were reviewed retrospectively. Patients' information, medical conditions, and laboratory data were extracted. All patients received IV colistin, and the majority of the patients showed in their culture reports multidrug-resistant bacteria such as Pseudomonas aeruginosa and Acinetobacter baumannii. Patients who had normal renal function received from 2.5 to 5.0 mg of colistin/kg, which was divided in two or three doses intravenously, for duration ranging between 10 and 14 days.

Results and conclusion

Approximately half of patients (48.93%) were fully recovered, while 19% of them were partially responded to colistin treatment. In the current study it was showed that IV colistin treatment against the multidrug-resistant bacteria (gram-negative bacteria) was strongly related to mild nephrotoxicity in addition to with a proper response as shown only in three of our patients.

Colistin co-administration with other nephrotoxins: experience of teaching hospital of Latvia

Background Colistin is a potentially nephrotoxic antibiotic used for the management of multidrug-resistant bacterial infections in critically ill patients. Co-administration with other nephrotoxins was reported as a potentially modifiable risk factor of colistin acute kidney injury. Objective To establish the role of colistin dosing and co-medications in development of colistin kidney injury. Setting Community teaching hospital in Latvia. Method Adult patients from intensive care units with diagnosed Gram-negative bacterial infections, undergoing colistin treatment for longer than 72 h, and not receiving renal replacement therapy were included in this retrospective study. Main outcome measure Colistin nephrotoxicity was defined as an increase in the serum creatinine level by at least 50% from the baseline after ≥ 48 h. Results In 73 of 87 cases, Acinetobacter baumannii pneumonia was diagnosed. The nephrotoxicity rate was 27.6% with a median onset of 8 days. In 79% of the cases, colistin was co-administrated with at least one potentially nephrotoxic agent. The most used nephrotoxins were loop diuretics (44 cases), non-steroidal anti-inflammatory drugs (19 cases) and vancomycin (11 cases). The use of nephrotoxins was similar in patients with colistin nephrotoxicity (group-1) and without it (group-2). Carbapenems were more common in group-2 (37% vs 62%, p = 0.004) and a colistin loading dose of 9 MU in group-1 (87% vs 62%, p = 0.027). However, in the multifactor regression analysis, the protective role of carbapenems was not confirmed. Conclusion Potentially nephrotoxic agents are commonly co-administrated with colistin. This study failed to prove their role in the development of acute kidney injury.