Bandemia as an Early Predictive Marker of Bacteremia: A Retrospective Cohort Study

Morphological changes in white blood cells in systemic inflammatory response syndrome (SIRS) with and without sepsis: An observational study

Background

This is an observational study which aims to research morphological changes of white blood cells in patients with Systemic Inflammatory Response Syndrome (SIRS) with and without sepsis and evaluate morphological changes in white blood cells as predictors of sepsis.

Methods

Patients aged 18 years or more with SIRS with sepsis and SIRS without sepsis were included and those with haematological disorders or pregnant patients were excluded. A total of 52 patients with SIRS with sepsis and 32 patients of SIRS without sepsis were included. Peripheral blood smear was prepared from the venous blood sample drawn. The presence of toxic granules, cytoplasmic vacuoles, and Dohle bodies in both cases of SIRS with sepsis without sepsis were assessed and it was compared with culture-positive sepsis and shock.

Results

The difference in the presence of toxic granules (55.8% vs. 12.5%; p <0.001), cytoplasmic vacuoles (30.8% vs. 6.3%; p -0.012), and Dohle bodies (17.3% vs. 0%; p = 0.012) was significantly higher in the SIRS with sepsis group, compared to the SIRS without sepsis group. In the subgroup analysis of patients in the sepsis group, it was observed that patients with positive blood culture (9%) had a significantly higher proportion of toxic granules (100% vs. 51.1%; p=0.059), cytoplasmic vacuoles (40% vs. 29.8%; p=0.637) and Dohle bodies (40% vs. 14.9%; p=0.202). However, these differences were not statistically significant.

Conclusion

Toxic granules and cytoplasmic vacuoles in the neutrophils of patients with SIRS with sepsis were found more frequently, compared to patients of SIRS without sepsis. Dohle bodies were found only in patients with sepsis and not in those with SIRS without sepsis.

Microbes and the fate of neutrophils

Neutrophils or polymorphonuclear neutrophils (PMNs) are an important component of innate host defense. These phagocytic leukocytes are recruited to infected tissues and kill invading microbes. There are several general characteristics of neutrophils that make them highly effective as antimicrobial cells. First, there is tremendous daily production and turnover of granulocytes in healthy adults-typically 1011 per day. The vast majority (~95%) of these cells are neutrophils. In addition, neutrophils are mobilized rapidly in response to chemotactic factors and are among the first leukocytes recruited to infected tissues. Most notably, neutrophils contain and/or produce an abundance of antimicrobial molecules. Many of these antimicrobial molecules are toxic to host cells and can destroy host tissues. Thus, neutrophil activation and turnover are highly regulated processes. To that end, aged neutrophils undergo apoptosis constitutively, a process that contains antimicrobial function and proinflammatory capacity. Importantly, apoptosis facilitates nonphlogistic turnover of neutrophils and removal by macrophages. This homeostatic process is altered by interaction with microbes and their products, as well as host proinflammatory molecules. Microbial pathogens can delay neutrophil apoptosis, accelerate apoptosis following phagocytosis, or cause neutrophil cytolysis. Here, we review these processes and provide perspective on recent studies that have potential to impact this paradigm.

A wide clinical spectrum of pulmonary affection in subjects with community-acquired Klebsiella pneumoniae liver abscess (CA-KPLA)

BACKGROUND

Klebsiella pneumoniae is a major pathogen of bacterial liver abscess in Asia. Particularly, patients with community-acquired Klebsiella pneumoniae liver abscess (CA-KPLA) tend to have a higher risk of invasive infection and pulmonary is a common invasive infectious site, making it a global clinical crisis. Therefore, considerable attention should be focused on the early prediction and active treatment strategies of such patients.

METHODS

The clinical data of 127 CA-KPLA cases hospitalized from January 2017 to February 2022 were collected from a single center. Risk factors were analyzed by the use of univariable and multivariable analysis. Furthermore, independent risk factors of pulmonary affection were utilized to construct a predictive nomogram.

RESULTS

The incidence of pulmonary affection in KPLA patients was 57.5% (73/127) and the majority manifested as nodular lesions with cavities and pleural effusion in chest CT images. Based on the predictive nomogram, the SOFA score (>2) was defined as the most dominant independent risk factor for the occurrence of pulmonary affection, followed by the maximum diameter of liver abscess (>3 cm), multiple liver abscesses, bacteremia, and badly-controlled diabetes sequentially. The validation of this nomogram also demonstrated good discriminative ability and satisfactory consistency. Finally, early drainage of liver abscess, initial combinational antibiotics, and early Carbapenem-including antibiotic usage were established as favorable factors for therapy in pulmonary affected CA-KPLA patients.

CONCLUSION

This study provided an effective model for the early prediction of pulmonary affection in patients with CA-KPLA and some rational strategies for their early therapeutic remission.