Mean platelet volume changes in infection

Limited value of platelet-related markers in diagnosing periprosthetic joint infection

OBJECTIVE

To evaluate the diagnostic values of serum platelet count (PC), mean platelet volume ratio (MPV), platelet count to mean platelet volume ratio (PVR), platelet to lymphocyte ratio (PLR), platelet to neutrophil ratio (PNR), PC/Albumin-globulin ratio (PC/AGR), and PC/C-reactive protein (PC/ CRP) in the diagnosis of periprosthetic joint infection (PJI).

METHODS

The medical records were retrospectively analyzed of the 158 patients who had undergone hip or knee revisions from January 2018 to May 2022. Of them, 79 cases were diagnosed with PJI and 79 with aseptic loosening (AL). PJI was defined using the Musculoskeletal Infection Society criteria. The plasma levels of CRP, the erythrocyte sedimentation rate (ESR), PC, MPV, PVR, PLR, PNR, PC/AGR, and PC/CRP in the 2 groups were recorded and analyzed. In addition, tests were performed according to different joint types. The receiver operating characteristic curve was used to calculate the sensitivity and specificity of each indicator. The diagnostic value for each indicator was calculated according to the area under the curve (AUC).

RESULTS

The PC, PVR, PLR and PC/AGR levels in the PJI group were significantly higher than those in the AL group, while PC/CRP levels were significantly lower (P < 0.001). The AUC for PC/CRP, and PC/AGR was 0.804 and 0.802, respectively, which were slightly lower than that of CRP (0.826) and ESR (0.846). ROC analysis for PC/CRP, and PC/AGR revealed a cut-off value of 37.80 and 160.63, respectively, which provided a sensitivity of 73.42% and 84.81% and a specificity of 75.95% and 65.82% for PJI. The area under the curve of PLR and PC was 0.738 and 0.702. The area under the curve values for PVR, PNR, and MPV were 0.672, 0.553, and 0.544, respectively.

CONCLUSIONS

The results of this study suggest that PC, PLR, PC/CRP, and PC/AGR values do not offer significant advantages over ESR or CRP values when employed for the diagnosis of PJI. PVR, PNR, and MPV were not reliable in the diagnosis of PJI.

Assistive diagnostic indicators for infections related to lumbar posterior interbody fusion internal fixation: platelet count and mean platelet volume

BACKGROUND

The most severe complication after posterior single-segment lumbar interbody fusion and internal fixation (PIFIF) surgery for degenerative lumbar diseases is deep surgical site infection (DSSI). Preoperatively diagnosing such complications proves to be challenging. Platelets, as acute-phase reactants, undergo changes in response to infections and inflammation. This study aims to assess whether platelet indices can further aid in the diagnosis of DSSI.

METHODS

A single-center retrospective study was conducted from January 2016 to February 2021 at Xi'an Jiaotong University-Affiliated Honghui Hospital, involving 83 patients who underwent revision surgery after PIFIF due to lumbar degenerative diseases. Among them, 24 patients were diagnosed with DSSI based on combined bacterial culture and imaging data. Preoperative complete serological indicators including erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and platelet count and mean platelet volume ratio (P/M ratio) were analyzed using receiver operating characteristic (ROC) curve analysis to determine cutoff values, sensitivity, and specificity. This was done to further assess the ability of these serological indicators to identify the occurrence of DSSI after PIFIF.

RESULTS

There were no significant differences in baseline demographic characteristics between the two patient groups (P > 0.05). The P/M ratio was 13.54 ± 5.05 in the aseptic revision group, while it was 19.21 ± 6.30 in the DSSI revision patients, showing a significant difference (P < 0.001). ROC curve analysis revealed that the optimal cutoff value for the P/M ratio was 17.50, with a sensitivity of 58.3% and a specificity of 78.6%. The areas under the curve (AUC) for ESR, CRP, and P/M ratio were 0.797, 0.845, and 0.756, respectively. The negative predictive value (NPV) was 87.04%, 89.47%, and 82.45%, respectively; the positive predictive value (PPV) was 58.62%, 69.23%, and 53.84%, respectively, for ESR, CRP, and P/M ratio, respectively. When P/M ratio is used in combination with ESR and CRP, the AUC is 0.887, with a sensitivity of 95.4%, specificity of 67.8%, NPV of 97.56%, PPV of 54.76%. The diagnostic performance of the model for evaluating DSSI is significantly improved compared to using ESR and CRP alone (P < 0.05).

CONCLUSION

Platelets and their related serum biomarkers are closely associated with DSSI. The P/M ratio can serve as a reliable test for screening DSSI and is worth considering for inclusion in the assessment of patients at risk of developing DSSI after potential PIFIF surgery.

Diagnosis of Periprosthetic Joint Infection: The Utility of Biomarkers in 2023

Periprosthetic joint infection (PJI) is a rare yet devastating complication following total joint arthroplasty (TJA). Early and accurate diagnosis of PJI is paramount in order to maximize the chances of successful treatment. However, we are yet to identify a single "gold standard" test for the diagnosis of PJI. As a result, the diagnosis of PJI is often challenging. Currently, the 2018 ICM definition of PJI is the only validated diagnostic criteria available. This article will review the importance of serum and synovial biomarkers in the diagnosis of PJI. In addition, it will provide a brief overview of the emerging modalities for the identification of infections in this setting.

Globulin and Albumin/Globulin Ratios as Potential Biomarkers for the Diagnosis of Acute and Chronic Peri-Prosthetic Joint Infections: A Retrospective Study

Background: Peri-prosthetic joint infection (PJI) is the most serious complication after prosthetic joint replacement. However, the diagnosis of PJI remains challenging for clinicians because of the lack of a gold standard. The purpose of this study was to investigate the diagnostic significance of serum globulin, albumin/globulin, and other biomarkers in acute and chronic periprosthetic infections. Patients and Methods: A retrospective study of 162 patients with PJI and aseptic loosening between January 2016 and March 2021 at our institution was performed in three groups. There were 20 patients with acute infection in group A, 36 patients with chronic infection in group B, and 106 patients with aseptic loosening in group C. Globulin, albumin/globulin, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), platelet count (PLT), mean platelet volume (MPV), d-dimer, and platelet count/mean platelet volume ratio (PMR) levels were recorded. The area under the curve (AUC) was used to measure the diagnostic value of globulin and albumin/globulin with other biomarkers for PJI. Results: Compared with the aseptic loosening group, the acute and chronic PJI group had higher levels of CRP, ESR, d-dimer, globulin, PLT, and PMR (p < 0.01) and lower levels of albumin/globulin and MPV (p < 0.01). The optimal cutoff, AUC, sensitivity, and specificity of CRP, albumin/globulin, ESR, and globulin were: CRP, 8.3 mg/L, 0.903, 78.57%, and 88.68%; albumin/globulin, 1.31, 0.899, 91.07%, and 73.58%; ESR, 32 mm/h, 0.888, 75.%, and 85.85%; globulin, 29.5 g/L, 0.880, 91.07%, and 72.64%. Conclusions: Globulin and albumin/globulin have excellent diagnostic value for acute and chronic PJI and are promising potential biomarkers for the diagnosis of PJI. The diagnostic performance of albumin/globulin is superior to that of ESR and similar to that of CRP.

The Diagnostic Accuracy of Neutrophils to Lymphocytes Ratio, Platelets to Lymphocytes Ratio, Monocytes to Lymphocytes Ratio, and Platelets to Mean Platelet Volume Ratio in Diagnosing Periprosthetic Knee Infections. Are Gender-Specific Cutoff Values Needed?

BACKGROUND

This study aimed to assess the most appropriate thresholds for neutrophils to lymphocytes ratio (NLR), platelets to lymphocytes ratio, monocytes to lymphocytes ratio (MLR), and platelets to mean platelet volume ratio in patients who had a suspected prosthetic knee infection. Furthermore, we evaluated the diagnostic accuracy of our proposed thresholds by men and women.

METHODS

A total of 261 consecutive patients affected by painful total knee arthroplasty were included. International Consensus Meeting diagnostic criteria were used to identify periprosthetic infections. Sensitivity, specificity, positive, and negative predictive values were calculated for each cutoff value obtained. The area under the receiver operating characteristic curve was evaluated.

RESULTS

NLR reported the best diagnostic accuracy. MLR and NLR reported higher area under the curves in men and women. We obtained an MLR value ≥0.30 (optimal cutoff value for men) and ≥0.17 (optimal cutoff value for women). In men, the sensitivity and the specificity were 0.71 and 0.77, respectively, versus 0.82 and 0.29, in women. For NLR, we obtained a value ≥2.52 (best cutoff value for men) and ≥2.46 (best cutoff value for women). These cutoffs reported a sensitivity and specificity of 0.71 and 0.88 versus 0.54 and 0.76 in men and women, respectively.

CONCLUSION

These biomarkers present a low diagnostic accuracy in periprosthetic joint infection detection. Men whose MLR and NLR were above cutoff values had a 77 and 88% probability of presenting a septic prosthetic failure. NLR of at least 2.46 was reasonably sensitive for women who have a periprosthetic knee infection.

LEVEL OF EVIDENCE

Diagnostic study, Level II.

Diagnostic Performance of Neutrophil to Lymphocyte Ratio, Monocyte to Lymphocyte Ratio, Platelet to Lymphocyte Ratio, and Platelet to Mean Platelet Volume Ratio in Periprosthetic Hip and Knee Infections: A Systematic Review and Meta-Analysis

The current literature on the diagnosis of periprosthetic joint infection provides controversial evidence on the diagnostic accuracy of MLR, NLR, PVR, and PLR. Therefore, this critical literature search and meta-analysis was aimed to summarize the diagnostic accuracy of these biomarkers for the diagnosis of hip and knee prosthetic infection. According to the PRISMA flowchart, we searched MEDLINE, Scopus, and Web of Science, for studies on these ratios for diagnosing PJI. Sensitivity, specificity, positive and negative likelihood ratio, diagnostic odds ratio, and AUC were analyzed. We included 11 articles in our meta-analysis, including 7537 patients who underwent total hip and knee arthroplasties; among these, 1974 (26%) patients reported a joint infection. The pooled sensitivity and specificity were 0.72 and 0.74, respectively, for NLR, 0.72 and 0.77 for PVR, and 0.77 and 0.75 for PLR. The sensitivity of MLR ranges from 0.54 to 0.81, while the specificity ranges from 0.78 to 0.81. Regarding the evaluation of AUCs, the best diagnostic performance was achieved by MLR (AUC = 0.77) followed by PLR (AUC = 0.75), NLR (AUC = 0.73), and PVR (AUC = 0.70). This meta-analysis demonstrates a fair diagnostic accuracy of these ratios, thus not being useful as a screening tool.

Diagnostic value of platelet indices in infected nonunion: a retrospective study

BACKGROUND

The diagnostic value of platelet indices has been evaluated in various infectious diseases but not in infected nonunion. The purpose of this study was to assess the usefulness of platelet indices for diagnosis of infected nonunion after open reduction and internal fixation.

METHODS

This retrospective study was performed in patients who underwent primary fracture nonunion revision surgeries from January 2016 to December 2021. A total of 297 patients were included in the study: 96 with infected nonunion (group A) and 201 with aseptic nonunion (group B). Receiver operator characteristic (ROC) curve analysis was performed to evaluate diagnostic value of each index. Area under the curve (AUC), sensitivity, specificity, and positive and negative predictive values were calculated and compared.

RESULTS

Demographic characteristics were comparable between the two groups. White blood cell (WBC) count, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), plasma fibrinogen, plasma D-dimer, platelet count (PC), plateletcrit, and ratio of platelet count to mean platelet volume (PC/MPV) were significantly higher, and MPV and platelet distribution width (PDW) significantly lower, in group A than in group B (P < 0.05). ROC analysis showed PC/MPV and plasma fibrinogen to have better diagnostic value than the other coagulation indicators (AUC of 0.801 and 0.807, respectively). The combination of ESR, plasma fibrinogen, and PC/MPV had good sensitivity and specificity for diagnosis of infected nonunion. PC/MPV had better diagnostic value than ESR and plasma fibrinogen in the subgroup of patients with coagulation-related comorbidities.

CONCLUSIONS

Plasma fibrinogen and PC/MPV ratio might be useful parameters for early diagnosis of infected nonunion.

Analysis of children with Henoch-Schonlein purpura secondary to infection

OBJECTIVES

Henoch-Schonlein purpura (HSP) is the most common childhood vasculitis, infection is the most essential inducement. We hypothesized that infection could impact the blood routine characteristics and/or outcome of vasculitis. Thus, we aim to find the most common infectious agent in HSP patients and identify convenient indicators to predict renal involvement in HSP patients with infection.

METHOD

We conducted a retrospective study of 208 HSP children and 98 healthy children. Clinical parameters were compared in those cases.

RESULTS

A total of 68.75% of patients were infected with various pathogens. The mean platelet volume (MPV) (P < 0.02) was lower in HSP patients with infection than patients without infection. Mycoplasma pneumoniae (MP) infection accounted for the largest proportion (45.77%). MPV in HSP nephritis (HSPN) group was lower than in HSP patients (excluded renal involvement) in patients with MP infection. Logistic regression analysis found that age and MPV were risk factors for the occurrence of MP-infected HSPN. The receiver operating characteristic curve (ROC) analysis showed that the combination of MPV with the onset age at the optimal cut-off point had 81% sensitivity in predicting whether HSP patients with MP infection would develop into HSPN.

CONCLUSIONS

Our research revealed that MP was the most commonly infected pathogen of children's HSP. MPV was an essential predictor of nephritis in HSP patients with MP infection. This discovery can prompt clinical treatments as well as reduce costs. Key Points • Mycoplasma pneumoniae (MP) accounts for the largest proportion in HSP children with infection. • MPV can be used as a predictor for the development of MP-triggered HSP to HSPN.

Role of Monocyte-to-lymphocyte Ratio, Mean Platelet Volume-to-Platelet Count Ratio, C-Reactive Protein and Erythrocyte Sedimentation Rate as Predictor of Severity in Secondary Traumatic Brain Injury: A Literature Review

BACKGROUND: Secondary traumatic brain injury (TBI) is injury to the brain following primary TBI because of neuroinflammation as consequences of neuronal and glial cell injury which cause release of various inflammation cytokine and chemokine. Biomarker examination to predict the severity of secondary TBI is important to provide appropriate treatment to the patient. This article reviews possibility several common laboratory parameter such as monocyte-to-lymphocyte ratio (MLR), mean platelet volume-to-platelet count (PC) ratio (MPV-PCR), c-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) to predict severity of secondary TBI. LITERATURE REVIEW: TBI activates microglia which increase infiltration and proliferation of monocyte. Neuroinflammation also increases thrombopoiesis which leads to increase megakaryocytes production. In the other hand, due to disruption of brain blood vessels because of trauma, coagulation cascade is also activated and leads to consumptive coagulopathy. These are reflected as high monocyte count, low PC, and high MPV. Lymphocyte count is reported low in TBI especially in poor outcome patients. CRP is an acute phase reactant that increased in inflammation condition. In TBI, increased production of Interleukin-6 leads to increase CRP production. In head injured patients, ESR level does not increase significantly in the acute phase of inflammation but last longer when compared to CRP. CONCLUSION: MLR, MPV-PCR, CRP, and ESR could be predictor of severity in secondary TBI.

Low value of platelet count to mean platelet volume ratio to diagnose chronic PJI: A case control study

INTRODUCTION

Numerous tests are being evaluated in order to aid the diagnosis of periprosthetic infections since it is a complicated and sometimes inconclusive process. The purpose of this study was to assess the diagnostic performance of platelet count to mean platelet volume ratio as a tool to aid the diagnosis of periprosthetic joint infections. The investigated questions were: "Is platelet count/mean platelet volume ratio more sensitive or specific than C-reactive protein (CRP) or erythrocyte sedimentation rate (ESR) in the diagnosis of periprosthetic joint infections?" and "Does platelet count/mean platelet volume ratio increase the accuracy of periprosthetic joint infection diagnosis?".

HYPOTHESIS

Platelet count/mean platelet volume ratio increases the accuracy of periprosthetic joint infection diagnosis.

MATERIALS AND METHODS

This study was performed retrospectively on patients who underwent revision hip or knee arthroplasty between 2016 and 2019. 62 patients with 33 aseptic (AR) and 29 septic revision (SR) who met our inclusion criteria were included. The sensitivity, specificity and diagnostic performance of CRP, ESR and platelet count/mean platelet volume values were analyzed and compared.

RESULTS

The demographic characteristics were similar between groups. Staphylococcus aureus and Staphylococcus epidermidis were the most commonly encountered microorganisms, while seven patients had negative cultures in SR group. ESR, CRP and platelet count/mean platelet volume values were significantly higher in SR group compared to AR group (p<0.01). ROC analysis for platelet count/mean platelet volume ratio revealed a cut-off value at 35.3 which provided 75.9% sensitivity and 78.8% specificity for periprosthetic joint infections. Platelet count/mean platelet volume ratio yielded lower sensitivity and similar specificity compared to ESR and CRP values. Platelet count/mean platelet volume had a lower area under curve value, indicating a poorer diagnostic performance compared to ESR and CRP.

DISCUSSION

The diagnostic performance of platelet count/mean platelet volume ratio is low and current findings do not support its usage to increase the accuracy of periprosthetic joint infections diagnosis.

LEVEL OF EVIDENCE

III; diagnostic case-control study.

Platelet Indices and Their Kinetics Predict Mortality in Patients of Sepsis

Platelet indices are inexpensive, easily accessible parameters and potentially useful prognostic indicators in sepsis. In this study we explore the differences in platelet indices and their kinetics between sepsis survivors and non-survivors. A retrospective cohort-study of 97 cases of culture-positive sepsis at a tertiary-care center in North India. Demographics, clinical and laboratory parameters at admission were assessed. Platelet count (PLT), mean-platelet-volume (MPV), platelet-distribution-width (PDW) and plateletcrit (PCT) on admission, and third, fifth and last days of hospitalization were analyzed. Fractional change in platelet indices (ΔMPV_72h, ΔPDW_72h, ΔPCT_72h, and ΔPLT_72h) by day-3 were calculated. Unpaired and paired t-tests were used to compare survivors with non-survivors, and to study the change in platelet indices with time. Logistic regression was used for multivariate analysis. ROC-curves and optimum cut-offs to predict mortality were obtained. There were 64 survivors. Non-survivors had significantly higher ΔMPV_72h, ΔPDW_72h, day-1 MPV and PDW, and lower ΔPLT_72h. MPV and PDW increased, and PLT decreased with time among non-survivors. Trends were reversed in survivors. Only MPV and PDW showed significant change by day-3. Both were independent predictors of mortality on multivariate analysis, alongside ΔMPV_72h and ΔPLT_72h. On ROC analysis, MPV, PDW, ΔMPV_72h, ΔPDW_72h and ΔPLT_72h effectively predicted mortality. Cut-off for MPV was 10.25 fL (sensitivity = 93.9%, specificity = 60.9%), and PDW, 12.6% (sensitivity = 84.8%, specificity = 51.6%). A rise in MPV and a fall in PLT was associated with mortality in this study. MPV and PDW values at admission are effective predictors of mortality and may be used in conjunction with traditional parameters.

Diagnostic Utility of Platelet Count/Lymphocyte Count Ratio and Platelet Count/Mean Platelet Volume Ratio in Periprosthetic Joint Infection Following Total Knee Arthroplasty

BACKGROUND

Diagnosing a periprosthetic joint infection (PJI) can be challenging and often requires a combination of clinical and laboratory findings. Monocyte/lymphocyte ratio, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio (PLR), and platelet/mean platelet volume ratio (PVR) are simple predictors for inflammation that can be readily obtained from complete blood count. The aim of this study is to evaluate the diagnostic utility of these markers in predicting PJI in total knee arthroplasty (TKA) patients.

METHODS

A total of 538 patients who underwent revision TKA with calculable marker ratios prerevision in 2 groups were evaluated: (1) 206 patients with a preoperative diagnosis of PJI (group I) and (2) 332 patients treated for revision TKA for aseptic failures (group II). The diagnostic abilities of the markers were assessed via receiver operator characteristic curve analysis.

RESULTS

The optimal threshold of PVR at 30.82 had the highest sensitivity of 87.7%, while the optimal threshold of PLR at 234.13 had the highest specificity of 82.5%. Both PLR and PVR, when combined with Musculoskeletal Infection Society thresholds for erythrocyte sedimentation rate, C-reactive protein, synovial WBC, and PMN%, achieve significantly higher sensitivity and specificity rates for PJI at or above 97% (PLR: 99.03%; 98.80%; PVR: 98.54%;97.89%).

CONCLUSION

Our study demonstrates that PVR and PLR, which are readily available and inexpensive to obtain from complete blood counts, when combined with serum and synovial fluid markers have increased sensitivity and specificity comparable to that of alpha defensin. This suggests that PVR and PLR can be used together with other hematologic and aspirate markers to increase the accuracy of PJI diagnosis in TKA patients.

Inferior performance of established and novel serum inflammatory markers in diagnosing periprosthetic joint infections

Purpose

Besides other diagnostic test methods, established serum inflammatory markers such as serum C-reactive protein or leukocyte count are widely used preoperatively to aid in diagnosing periprosthetic joint infections (PJI). Although low accuracies were reported, these parameters are easily accessible and routinely available. Novel biomarkers with promising results in diagnosing PJI (platelet count to mean platelet volume ratio) or other infectious conditions (percentage of neutrophils, neutrophils to lymphocytes ratio) were described. The purpose of this study was to investigate the diagnostic value of established and novel serum inflammatory biomarkers for the diagnosis of PJI so as to compare the results to find the serum inflammatory marker with the best performance.

Methods

In 177 patients with a previous total hip (n = 91) or knee (n = 86) arthroplasty and indicated revision surgery, the diagnostic value of the routinely available serum inflammatory markers C-reactive protein (CRP), white blood cell count (WBC), percentage of neutrophils (%N), neutrophils to lymphocytes ratio (NLR), fibrinogen and platelet count to mean platelet volume ratio (PC/mPV) were examined retrospectively via receiver operating characteristic curve analysis (AUC). The curves were compared using the z-test.

Results

Sensitivities of serum CRP, WBC, %N, NLR, fibrinogen and PC/mPV were calculated with 68%, 36%, 66%, 63%, 69% and 43%, respectively. Specificities were 87%, 89%, 67%, 73%, 89% and 81%, respectively. Serum CRP (0.78) and fibrinogen (0.79) showed significantly better AUCs compared with serum WBC (0.63), %N (0.67), NLR (0.68) and PC/mPV (0.62) (p < 0.0001). Patients with PJI caused by a low-virulent microorganism (median CRP: 17.6 mg/L) obtained lower CRP levels compared with infections caused by high-virulent microorganisms (median CRP: 49.2 mg/L; p = 0.044). The combination of CRP and fibrinogen showed a better sensitivity (77%) with similar specificity (83%) than one method alone but not at a significant level (CRP (p = 0.200); fibrinogen (p = 0.437)).

Conclusion

Serum CRP and fibrinogen showed the best accuracies among these widely available serum inflammatory parameters. However, due to the insufficient performance, these biomarkers can only be recommended as suggestive criteria in diagnosing PJI. The preoperative workup should always be complemented by more specific tests such as synovial fluid analysis.

Usefulness of Blood Parameters for Preliminary Diagnosis of Brucellosis

BACKGROUND

Human brucellosis is a multisystem disease with a wide range of clinical signs which often leads to misdiagnosis and treatment delay. Early diagnosis of this disease can prevent the serious complications and mismanagements. This study aimed to evaluate the hematological parameters with predictive value for the diagnosis of brucellosis.

METHODS

In this prospective case-control study which was done during 2015-2017 in Imam Reza Hospital, Kermanshah Province, west Iran, 100 patients with a confirmed diagnosis of brucellosis (brucellosis group) and 100 healthy individuals (control group) were studied. The hematological parameters, including hemoglobin (Hb), red blood cell (RBC), white blood cell (WBC) count, lymphocyte count, neutrophil count, platelet count (PLTs), mean platelet volume (MPV), platelet distribution width (PDW), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) of both groups were recorded. The data were statistically compared between the brucellosis and the control groups.

RESULTS

The mean age of patients and healthy groups was 44.04 ± 23.11 and 37.92 ± 24.80, respectively (P = 0.062). The WBC, CRP and neutrophil counts were significantly higher in the brucellosis group (P < 0.05). Based on the receiver operating characteristic (ROC) analysis, the sensitivity and specificity were 54% and 66% for the WBC, 45% and 71% for the neutrophil and 65% and 72% for the CRP, respectively. There was no statistically significant difference between the two groups in terms of Hb, RBC, WBC, lymphocyte and platelet count, MPV, PDW and ESR (P > 0.05).

CONCLUSION

The results of this study indicate that WBC, CRP and neutrophil count can be used as valuable markers in the preliminary diagnosis of brucellosis. However, further researches are required to standardize these parameters for various forms of brucellosis.

A Novel Adjunct Indicator of Periprosthetic Joint Infection: Platelet Count and Mean Platelet Volume

BACKGROUND

Diagnosing a periprosthetic joint infection (PJI) is difficult and often requires a combination of objective findings. The purpose of this study is to determine whether platelets, a known acute phase reactant, would be able to further aid in the diagnosis of PJI.

METHODS

A single-institution retrospective review study was performed on all revision total hip and knee arthroplasties done between 2000 and 2016 (n = 4939). PJI was defined by Musculoskeletal Infection Society criteria (n = 949). Platelet count and mean platelet volume were assessed from each patient's preoperative complete blood count. These values were then assessed as a ratio via receiver operating characteristic (ROC) curve analysis.

RESULTS

The platelet count to mean platelet volume ratio for PJI patients was 33.45 compared to 25.68 for patients in the aseptic revision cohort (P < .001). ROC curve analysis demonstrates that a ratio of 31.70 has a sensitivity of 48.10 (95% confidence interval 44.9-51.4) and a specificity of 80.85 (95% confidence interval 79.6-82.1). This specificity was higher than that of both estimated sedimentation ratio (ESR) and C-reactive protein (CRP) for the same cohorts using optimal values determined via ROC curve analysis. When used in conjunction with ESR and CRP, there was a statistically significant increase in the diagnostic performance of the model used to assess PJI relative to the model that just employed ESR and CRP (P < .05).

CONCLUSION

Our study demonstrates that platelets and their associated serum biomarkers are associated with PJI and warrant consideration in patients who are being evaluated for potential PJI.

Effectiveness of complete blood count parameters for predicting intracranial injury in children with minor head trauma

Objective: We aimed to investigate the relationship between trauma severity and platelet indices (PI) and white blood cell (WBC) count to identify traumatic brain injury (TBI) in children with minor head trauma (MHT). Materials and methods: This prospective study included children with acute isolated MHT who underwent head computed tomography (CT) based on Pediatric Emergency Care Research Network (PECARN) criteria. Mean platelet volume (MPV), platelet distribution width (PDW), MPV to platelet ratio (MPV/PL), MPV to white blood cell ratio (MPV/WBC), and MPV to Neutrophil ratio (MPV/Neu) were evaluated. Results: 86 children with MHT and 245 controls were included the study. WBC, Neu count, MPV, MPV/WBC, MPV/Neu and MPV/PI ratios were statistically different among patients with abnormal CT, patients with normal CT and healthy controls (p < 0.05). For predicting abbreviated injury score (AIS) > 1, the AUC values of WBC, neutrophil, MPV/WBC and MPV/Neu were 0.746, 0.739, 0.726 and 0.724, respectively. Conclusion: In children with MHT who underwent CT, WBC, Neu counts, MPV/WBC and MPV/Neu ratios may be helpful for predicting the severity of trauma in pediatric emergency department.

Are fibrinogen and complete blood count parameters predictive in incarcerated abdominal hernia repair?

Therapeutic delays in cases of external incarcerated hernias typically result in increasing morbidity, mortality, and health expenditures. We investigated the diagnostic role of blood fibrinogen level, white blood count (WBC), mean platelet volume (MPV), and platelet distribution width (PDW) in patients with incarcerated hernia. Two groups, each containing 100 patients, were studied. Group A underwent elective, and group B underwent incarcerated and urgent external hernia repair. We observed high fibrinogen and WBC levels but low MPV and PDW values for patients in group B. Contrary to our expectations, we found lower MPV and PDW values in the complicated group than in the elective group. The morbidity rate and cost burden were higher in group B, and the results were statistically significant. Early operation should be recommended for patients with incarcerated external hernias if their fibrinogen and WBC levels are high.

The impact of various platelet indices as prognostic markers of septic shock

Introduction

Platelet indices, including mean platelet volume (MPV), are readily available blood tests, although their prognostic value in patients with septic shock has not been fully explored. Current evidence has found contradictory results. This study aims to explore the behavior of platelet indices in septic shock and their clinical prognostic value.

Methods

Charts of septic shock patients from January to December 2012 in a tertiary medical center in Northern China were reviewed retrospectively. Platelet indices were recorded during the first five consecutive days after admission, as well as the penultimate and the last day of hospital stay. The data were compared between surviving and non-surviving patients.

Results

A total of 124 septic shock patients were enrolled. Thirty-six of the patients survived and 88 of them expired. MPV in the non-survivor group was higher than that of the survivor group, especially on the last day. PDW and PLCR showed increased trends, while PCT and PLT decreased in the non-survivor group. Among the PLT indices, MPV had the highest area under the receiver operating characteristic curve (0.81) with a precision rate of 75.6% at a cut-off of 10.5.Compared with other more usual septic shock prognostic markers, MPV is second only to lactate for the highest area under the curve.

Conclusion

A statistically significant difference was seen between survivors and non-survivors for platelet indices which make them easily available and useful prognostic markers for patients in septic shock.

Changes in platelet count and mean platelet volume during infectious and inflammatory disease and their correlation with ESR and CRP

BACKGROUND

The measurements of platelet count and mean platelet volume (MPV) are routinely available nowadays. The aim of this study was to evaluate the platelet count and MPV trend in infectious and inflammatory processes. We also investigated whether these parameters were associated with the known markers of disease activity, erythrocyte sedimentation rate (ESR) and C- reactive protein (CRP).

METHODS

This cross-sectional study was conducted on 100 children with diagnosis of infectious and inflammatory diseases. Platelet count, MPV, ESR, and CRP were measured at the time of hospitalization and thereafter in the recovery phase.

RESULTS

Mean platelet count increased in the patients at the time of admission in the hospital compared to the recovery and discharge time (mean 430,820 ± 134,643/μl vs. 350,970 ± 99,374/μl, P < 0.001). However, MPV decreased significantly during the same period (8.2 ± 1.1 fl vs. 8.7 ± 0.9, P < 0.001). Platelet count was directly correlated with CRP (mean 6.4 ± 0.3 mg/l), (r = 0.49, P < 0.001) and ESR (mean 10.9 ± 1.1 mm/hr), (r = 0.32, P = 0.003). On the other hand, MPV was inversely correlated with CRP (r = 0.39, P < 0.001) and ESR (r = -0.24, P = 0.034).

CONCLUSIONS

This study demonstrated a higher level of platelet count and lower MPV in the patients with active disease compared to the recovered patients. These parameters were well correlated with the known disease activity markers. We propose that platelet parameters can be considered as reliable markers for assessment of disease activity and response to treatment.

The value of mean platelet volume in the determination of community acquired pneumonia in children

BACKGROUND

Mean platelet volume (MPV) is a reflection of platelet size, which has been shown to correlate with platelet function and activation. The aim of this study was to evaluate whether MPV could be used for the diagnostic tool of community-acquired pneumonia (CAP) and for making the decision for hospitalization.

METHODS

The computerized records of children aged 1 to 18 years who were diagnosed with CAP based on WHO criteria were evaluated. A standard protocol was followed, and patients with severe CAP were hospitalized. CAP patients were divided into two groups based on disease severity. The control group consisted of age and gender matched healthy children during the study period. Values for hemoglobin, white blood cell count (WBC), platelet count, MPV and C-reactive protein (CRP) obtained on first presentation were recorded for each patient.

RESULTS

A total of 196 patients were diagnosed with CAP during the study period, 108 (55.1%) of which had severe disease, which required hospitalization (Group 1a), while the remaining 88 (44.9%) were followed-up as outpatients (Group 1b). The control group consisted of 100 healthy children (Group 2). Patients with CAP had lower MPV values than their healthy counterparts (7.1 ± 0.68 vs. 8.31 ± 1.2 fL; p<0.001). MPV value was significantly higher in hospitalized CAP patients compared to outpatients (7.32 ± 0.71 vs. 6.83 ± 0.5 fL; p=0.012). ROC curve analysis suggested that MPV level cut-off point for making a diagnosis of CAP was 8.1 fL, with a sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of 91%, 51%, 80.8% and 70.5%, respectively.

CONCLUSIONS

Our findings suggest that MPV may be a useful predictor for diagnosed CAP but low specificity and NPV rates may lead to the false-negative diagnosis.