Novel and Rapid Diagnostics for Common Infections in the Critically Ill Patient

There are several novel platforms that enhance detection of pathogens that cause common infections in the intensive care unit. These platforms have a sample to answer time of a few hours, are often higher yield than culture, and have the potential to improve antibiotic stewardship.

Novel and Rapid Diagnostics for Common Infections in the Critically Ill Patient

There are several novel platforms that enhance detection of pathogens that cause common infections in the intensive care unit. These platforms have a sample to answer time of a few hours, are often higher yield than culture, and have the potential to improve antibiotic stewardship.

Intra-abdominal Infections

Intra-abdominal infections (IAIs) are a common cause of sepsis, and frequently occur in intensive care unit (ICU) patients. IAIs include many diagnoses, including peritonitis, cholangitis, diverticulitis, pancreatitis, abdominal abscess, intestinal perforation, abdominal trauma, and pelvic inflammatory disease. IAIs are the second most common cause of infectious morbidity and mortality in the ICU after pneumonia. IAIs are also the second most common cause of sepsis in critically ill patients, and affect approximately 5% of ICU patients. Mortality with IAI in ICU patients ranges from 5 to 50%, with the wide variability related to the specific IAI present, associated patient comorbidities, severity of illness, and organ dysfunction and failures. It is important to have a comprehensive understanding of IAIs as potential causes of life-threatening infections in ICU patients to provide the best diagnostic and therapeutic care for optimal patient outcomes in the ICU.

Novel Multiparametric Nomogram for Overall Survival Prediction in Complicated Intra-Abdominal Infection: A Multicenter Study in China

Background: Complicated intra-abdominal infections (cIAIs) in the abdominal cavity or within an abdominal organ are numerous and frequent dangerous entities in the treatment of critically ill patients. Early clinical evaluation is necessary.

Methods: This retrospective multicenter study included patients from 10 intensive care units (ICUs). Risk factors for the overall survival (OS) of patients with cIAI were selected using least absolute shrinkage and selection operator regression, and a nomogram was constructed subsequently. Calibration curve and receiver operating characteristic (ROC) curve were used to evaluate the calibration and discriminative ability.

Results: In total, 544 patients diagnosed with cIAI were enrolled and divided into the study (n = 276) and validation (n = 268) sets. Sex, acute gastrointestinal injury, acute kidney injury, rare bacterium infection, Charlson score, and APACHE II score were identified as independent risk factors and were constructed for the nomogram. The nomogram showed marked calibration capability with a concordance index (C-index) of 0.909 and 0.831 in the study and validation set, respectively. Compared with the common clinical prognostic scoring system, the nomogram achieved the highest discrimination ability with an area under the curve (AUC) value of 0.91 and 0.83 in the study set and validation set, respectively.

Conclusions: Our newly constructed nomogram provides a useful tool for risk stratification and prognosis evaluation of cIAI.

Clinical and Microbiological Characteristics of Patients with Complicated Intra-abdominal Infections in Intensive Care Unit

In order to investigate the clinical and microbiological characteristics of patients with complicated intra-abdominal infections (cIAIs) in intensive care unit (ICU), the clinical data of 612 cIAIs patients from January 2016 to December 2018 were retrospectively collected. Clinical characteristics, distribution of pathogens and drug resistance were statistically analyzed. It was found that patients with community-acquired intra-abdominal infections (CA-IAIs) made up a majority of cIAIs patients. The positive rate of abdominal drainage fluid culture was 55.56%. Gramnegative bacteria accounted for the majority, the most commonly isolated bacteria of which were Escherichia coli (20.96%), Klebsiella pneumoniae (10.20%) and Pseudomonas aeruginosa (5.57%). The most commonly isolated gram-positive bacteria were Enterococcus (16.88%) and Methicillin-resistant staphylococcus aureus (MRSA, 3.90%). Enterobacter isolates showed high resistance rate to most cephalosporins and low resistance rate to piperacillin/tazobactam and carbapenems. Extended spectrum beta-lactamase (ESBL) screen positive isolates from CA-IAIs patients showed an increasing trend in past three years. Enterococcus and MRSA showed high resistance rate to clindamycin, quinolone, erythromycin and tetracycline, while they showed high sensitivity rate to linezolid, tegacycline, teicoplanin and vancomycin. Our results indicate that isolated bacteria from abdominal drainage fluid show high resistance rates to commonly used antibiotics in ICU patients with cIAIs. The curative effects on diseases should be monitored continuously when antibiotics are used. Meanwhile, we should always keep eyes on drug-resistant bacteria, especially when the treatment efficacy is not good.

Elevated Levels of Plasma Mitochondrial DNA Are Associated with Clinical Outcome in Intra-Abdominal Infections Caused by Severe Trauma

BACKGROUND

The purpose of our study was to determine prospectively relationships between plasma mitochondrial deoxyribonucleic acid (mtDNA) concentration and clinical outcome in patients with intra-abdominal infections (IAIs) induced by severe abdominal trauma.

PATIENTS AND METHODS

The DNA was isolated from serum samples taken from patients with IAIs at hospital days zero, one, and two. Plasma mtDNA concentration was assessed by real-time polymerase chain reaction (PCR). The study population's clinical and laboratory data were analyzed.

RESULTS

The mtDNA damage-associated molecular patterns were expressed as a PCR threshold cycle number using four selected sequences. The patients with IAIs had significant higher plasma mtDNA than healthy control subjects. Patients with IAIs with sepsis apparently had elevated mtDNA levels compared with non-septic patients with IAIs (30.9 ± 2.0 vs. 28.7 ± 2.4; 33.3 ± 2.6 vs. 28.9 ± 2.4; 32.9 ± 1.6 vs. 31.2 ± 2.2; 33.1 ± 3.6 vs. 28.1 ± 2.2, respectively). Patients with IAIs in whom multiple organ dysfunction syndrome (MODS) developed also had increased mtDNA concentration compared with those who did not (31.0 ± 1.8 vs. 27.9 ± 1.8; 32.9 ± 2.4 vs. 27.8 ± 1.7; 32.9 ± 1.5 vs. 29.8 ± 1.7; 32.0 ± 3.8 vs. 27.1 ± 2.1, respectively). Baseline mtDNA concentration had high effectiveness in predicting death for patients with IAIs who had severe trauma using receiver operating characteristic analysis. Furthermore, serum mtDNA levels on admission correlated with the lactate concentration, but no significant correlations were found between mtDNA levels and levels of white blood cells, C-reactive protein, and procalcitonin.

CONCLUSIONS

Plasma mtDNA was associated with the occurrence of sepsis, MODS, and death in patients with IAIs caused by severe abdominal trauma.

The Surgical Infection Society Revised Guidelines on the Management of Intra-Abdominal Infection

BACKGROUND

Previous evidence-based guidelines on the management of intra-abdominal infection (IAI) were published by the Surgical Infection Society (SIS) in 1992, 2002, and 2010. At the time the most recent guideline was released, the plan was to update the guideline every five years to ensure the timeliness and appropriateness of the recommendations.

METHODS

Based on the previous guidelines, the task force outlined a number of topics related to the treatment of patients with IAI and then developed key questions on these various topics. All questions were approached using general and specific literature searches, focusing on articles and other information published since 2008. These publications and additional materials published before 2008 were reviewed by the task force as a whole or by individual subgroups as to relevance to individual questions. Recommendations were developed by a process of iterative consensus, with all task force members voting to accept or reject each recommendation. Grading was based on the GRADE (Grades of Recommendation Assessment, Development, and Evaluation) system; the quality of the evidence was graded as high, moderate, or weak, and the strength of the recommendation was graded as strong or weak. Review of the document was performed by members of the SIS who were not on the task force. After responses were made to all critiques, the document was approved as an official guideline of the SIS by the Executive Council.

RESULTS

This guideline summarizes the current recommendations developed by the task force on the treatment of patients who have IAI. Evidence-based recommendations have been made regarding risk assessment in individual patients; source control; the timing, selection, and duration of antimicrobial therapy; and suggested approaches to patients who fail initial therapy. Additional recommendations related to the treatment of pediatric patients with IAI have been included.

SUMMARY

The current recommendations of the SIS regarding the treatment of patients with IAI are provided in this guideline.

The Incidence, Clinical Outcomes, and Risk Factors of Thrombocytopenia in Intra-Abdominal Infection Patients: A Retrospective Cohort Study

Background

Studies on the incidence and risk factors of thrombocytopenia among intra-abdominal infection patients remain absent, hindering efficacy assessments regarding thrombocytopenia prevention strategies.

Methods

We retrospectively studied 267 consecutively enrolled patients with intra-abdominal infections. Occurrence of thrombocytopenia was scanned for all patients. All-cause 28-day mortality was recorded. Variables from univariate analyses that were associated with occurrence of hospital-acquired thrombocytopenia were included in a multivariable logistic regression analysis to determine thrombocytopenia predictors.

Results

Median APACHE II score and SOFA score of the whole cohort was 12 and 3 respectively. The overall ICU mortality was 7.87% and the 28-day mortality was 8.98%. The incidence of thrombocytopenia among intra-abdominal infection patients was 21.73%. Regardless of preexisting or hospital-acquired one, thrombocytopenia is associated with an increased ICU mortality and 28-day mortality as well as length of ICU or hospital stay. A higher SOFA and ISTH score at admission were significant hospital-acquired thrombocytopenia risk factors.

Conclusions

This is the first study to identify a high incidence of thrombocytopenia in patients with intra-abdominal infections. Our findings suggest that the inflammatory milieu of intra-abdominal infections may uniquely predispose those patients to thrombocytopenia. More effective thrombocytopenia prevention strategies are necessary in intra-abdominal infection patients.