Mean Platelet Volume is Reduced in Acute Appendicitis

Mean platelet volume and total white blood cells as diagnostic biomarkers for acute appendicitis at Omdurman military hospital: a cross-sectional study - 2021

BACKGROUND

Acute appendicitis (AA) is among the most common nontraumatic indications for emergent abdominal surgical procedures. However, accurately diagnosing all cases can be challenging, physical examination, biochemical markers, and imaging techniques can sometimes be insufficient. This study aimed to (a) compare the mean platelet volume (MPV) and total white blood cell count (TWBCs) in patients with or without histological evidence of an inflamed appendix and (b) determine the positive predictive value, negative predictive value, sensitivity, and specificity of both MPV and TWBCs as diagnostic biomarkers in the diagnosis of AA. We conducted this research at Omdurman Military Hospital, focusing on patients who presented with symptoms suggestive of AA.

MATERIALS AND METHODS

An analytical cross-sectional study conducted at Omdurman Military Hospital from December 2020 - December 2021. The study population was patients who presented to our emergency department with symptoms and signs suggestive of AA. Participants were patients operated on as cases of AA. Data variables included sociodemographic characteristics, clinical presentations, intraoperative appendix macroscopic findings, preoperative MPV and total white blood cell count (TWBCs), and postoperative histopathological findings.

RESULTS

A total of 106 patients were included in this study, with 75 (68.2%) males; half were 10-19 years old. Sixty-three patients (57.3%) had low (< 7.5 fL) MPV, whereas 47 (42.7%) had normal values. Comparing MPV to total white blood cells (TWBCs) revealed that MPV was more sensitive (84.6%) and specific (90%) than TWBCs during the first 24 h of inflammation. However, the TWBCs were more sensitive (97.2%) but less specific (94.7% vs. 100%) after 24 h of onset.

CONCLUSION

In this study, MPV was lower in patients with AA, while there was an increase in TWBCs. The high sensitivity and specificity of TWBCs and MPV indicated that they form a promising diagnostic marker for AA.

A cross-sectional study on evaluation of complete blood count-associated parameters for the diagnosis of acute appendicitis

BACKGROUND AND AIMS

Acute appendicitis is one of the common causes of abdominal surgeries, however, the rate of negative appendectomy is as high as 20% as the diagnosis of appendicitis is challenging. The study aimed to evaluate complete blood count (CBC)-associated parameters among positive and negative appendectomy patients and determine their diagnostic importance.

METHODS

In this cross-sectional study, patients who suspected of acute appendicitis were included. Preoperative blood samples taken from these patients for a complete blood count. Following parameters evaluated from their CBC: white blood cell (WBC), platelet (PLT), mean platelet volume (MPV), neutrophils-to-lymphocytes ratio, platelets-to-lymphocytes ratio, red cell distribution width (RDW), and platelet distribution width (PDW). These parameters analyzed for the positive and negative appendectomy patients using statistical analysis.

RESULTS

Of 200 patients included in the study, 30 patients (15%) underwent negative appendectomy. The mean neutrophils, WBC, red blood cells, neutrophils-to-lymphocytes, and platelets-to-lymphocytes ratio was significantly high among positive appendectomy patients, (P < .05), whereas MPV to platelet ratio was significantly less in this group. The highest diagnostic power for the diagnosis of appendicitis was of neutrophils-to-lymphocytes ratio with the sensitivity of 83.5% and the specificity of 90%.

CONCLUSION

The findings of our study indicate that neutrophils-to-lymphocytes ratio alone is not sufficient for preoperative diagnosis of acute appendicitis and other CBC-related parameters did not have good sensitivity and specificity. Further studies are therefore required in this area.

Platelet indices in patients with acute appendicitis: a systematic review with meta-analysis

Correlation between blood inflammatory parameters and acute appendicitis (AA) remains controversial. This meta-analysis aims to evaluate whether platelet (PLT) indices including mean platelet volume (MPV), PLT count, and platelet distribution width (PDW) are associated with AA. Pubmed, Embase, and Cochrane Library databases were searched for observational studies published from inception through April 2020 by two independent investigators. Studies reporting associations between platelet indices and AA were selected for inclusion. Standardized mean difference (SMD) and 95% confidence interval (CI) were estimated for continuous outcomes using a DerSimonian-Laird random-effects model. Of 842 records identified, 17 studies with a total of 6793 subjects met our inclusion criteria. Meta-analysis indicated that compared with those in healthy controls, significant decrease in MPV levels was observed in subjects with AA (SMD - 0.34; 95% CI - 0.56 to - 0.12; P = 0.003). Subgroup analyses represented a significant reduction of MPV levels in patients aged ≥ 30 years and non-complicated/non-perforated AA. Due to the small number of studies and patients included in each subgroup, these subgroup analyses need to be interpreted with caution. However, none of the levels of PLT (SMD - 0.13; 95% CI - 0.28-0.012; P = 0.071) or PDW (SMD 0.30; 95% CI - 0.22-0.83; P = 0.257) was seen decrease or increase in subjects with AA. This meta-analysis indicates a significant decrease in MPV levels in patients with AA, which makes MPV have the potential of serving as a biomarker for AA. The associations of other PLT indices with AA need to be further examined.

A novel and simple machine learning algorithm for preoperative diagnosis of acute appendicitis in children

INTRODUCTION

There is a tendency toward nonoperative management of appendicitis resulting in an increasing need for preoperative diagnosis and classification. For medical purposes, simple conceptual decision-making models that can learn are widely used. Decision trees are reliable and effective techniques which provide high classification accuracy. We tested if we could detect appendicitis and differentiate uncomplicated from complicated cases using machine learning algorithms.

MATERIALS AND METHODS

We analyzed all cases admitted between 2010 and 2016 that fell into the following categories: healthy controls (Group 1); sham controls (Group 2); sham disease (Group 3), and acute abdomen (Group 4). The latter group was further divided into four groups: false laparotomy; uncomplicated appendicitis; complicated appendicitis without abscess, and complicated appendicitis with abscess. Patients with comorbidities and whose complete blood count and/or pathology results were lacking were excluded. Data were collected for demographics, preoperative blood analysis, and postoperative diagnosis. Various machine learning algorithms were applied to detect appendicitis patients.

RESULTS

There were 7244 patients with a mean age of 6.84 ± 5.31 years, of whom 82.3% (5960/7244) were male. Most algorithms tested, especially linear methods, provided similar performance measures. We preferred the decision tree model due to its easier interpretability. With this algorithm, we detected appendicitis patients with 93.97% area under the curve (AUC), 94.69% accuracy, 93.55% sensitivity, and 96.55% specificity, and uncomplicated appendicitis with 79.47% AUC, 70.83% accuracy, 66.81% sensitivity, and 81.88% specificity.

CONCLUSIONS

Machine learning is a novel approach to prevent unnecessary operations and decrease the burden of appendicitis both for patients and health systems.

LEVELS OF EVIDENCE

III.

Accuracy of Mean Platelet Volume (MPV) and Red Cell Distribution Width (RDW) for the Diagnosis of Acute Appendicitis: Evaluation of Possible New Biomarkers

Introduction:

Acute appendicitis is the most common cause of the abdominal pain in surgery. Despite its significant prevalence, the diagnosis is associated with many problems in some cases, which leads to false appendectomy.

Objective:

The aim of this study was to determine the validity of diagnostic tests of mean platelet volume (MPV) and red cell distribution width (RDW), as a new possible tool in the diagnosis of acute appendicitis. Methods: In this study, all patients who referred to the emergency department of Besat Hospital, Hamadan, Iran, in 2015, with abdominal pain and first impression of acute appendicitis, undergone appendectomy, were evaluated. The diagnostic markers of pre-operative and post-operative pathology and the validity of MPV and RDW were determined in diagnosis of acute appendicitis.

Results:

Laboratory and clinical data from 438 patients, presenting the signs and symptoms of acute appendicitis with the mean age of 26.51±13.9 years, were examined (55.6% men). The sensitivity, specificity, positive and negative predictive value of MPV in the diagnosis of acute appendicitis were 59.77, 98.66, 99.5 and 34.26 percent, and for the RDW were 57.79, 56.00, 86.07 and 21.98 percent, respectively. The area under the receiver operating characteristic (ROC) curve for RDW and MPV was 0.61and 0.90, respectively. The mean of MPV in patients with normal pathologic outcome was 9.52±1.60 and in patients with acute appendicitis was 7.51±1.22. There was a significant difference between the mean MPV in both groups (p<0.001). The mean of RDW in patients with normal pathology were 13.42±1.97 and 13.05±1.09, in patients with acute appendicitis. There was a significant difference between the mean RDW of the two groups (p=0.009).

Conclusion:

MPV and RDW indexes have the potential to be used by the surgeons in diagnosis of acute and perforated appendicitis, especially in adults, in order to reduce unnecessary appendectomy, but MPV is more valid in screening acute appendicitis, compared to the RDW.

Mean platelet volume in preterm: a predictor of early onset neonatal sepsis

Background: Early onset sepsis (EOS) is potentially life-threatening problem especially in preterm. EOS diagnosis is challenging due to its non-specific signs and laboratory tests. Mean platelet volume (MPV) has been used as predictor of many inflammatory diseases.Objectives: To assess the correlation between serial MPV measurement and EOS occurrence in preterm infants and to determine MPV effectiveness in combination with C reactive protein (CRP) to diagnose EOS and mortality prediction.Methods: The study was carried out on 95 preterm infants with antenatal risk factor for EOS. Blood samples were taken for complete blood count (CBC) including MPV evaluated at birth (cord blood) and at 72 h of life. CRP analyzed on days 1 and 3, subsequently patients were identified in two groups: sepsis (n = 28) and no-sepsis (n = 67).Results: MPV was significantly higher on both day 1 (10.23 ± 0.92) fl and day 3 (10.77 ± 1.16) fL in the sepsis group compared with no-sepsis (8.11 ± 0.29) fl and (8.53 ± 0.42) fl, respectively. MPV of 8.6 fL was identified as cut off value in patients probably resulting in sepsis with a sensitivity of 97.14% and a specificity of 100%. MPV of 10.4 fl was determined as cut off value in patients possibly resulting in death with a sensitivity of 70% and a specificity of 82.5%. The combination of both MPV and CRP on day 1 resulted in improving performance of MPV with higher negative predictive value (93.1%) and higher sensitivity (80%).Conclusion: High cord blood and day 3 MPV can be used as surrogate marker for prediction of EOS and associated mortality in preterm neonates.

Diagnostic role of mean platelet volume in tonsillitis with and without peritonsillar abscess

Objective

To assess the diagnostic role of mean platelet volume in tonsillitis with and without peritonsillar abscess.

Methods

Mean platelet volume and other laboratory data were retrospectively investigated.

Results

Mean platelet volume was significantly lower in the tonsillitis group (7.8 per cent ± 0.7 per cent) than in the control group (8.7 per cent ± 0.6 per cent; p < 0.0001), and it was significantly lower in the abscess group (7.5 per cent ± 0.6 per cent) than in the no abscess group (8.0 per cent ± 0.7 per cent; p = 0.0277). White blood cell counts and C-reactive protein levels were not significantly different between patients with an abscess and those without. The mean platelet volume cut-off values for the diagnosis of tonsillitis and peritonsillar abscess were 7.95 fl and 7.75 fl, respectively.

Conclusion

Our results suggest that a decreased mean platelet volume is associated with the development and severity of tonsillitis. This finding provides useful diagnostic information for physicians treating patients with tonsillitis.

Can mean platelet volume play a role in evaluating the severity of acute pancreatitis?

AIM

To investigate serum mean platelet volume (MPV) levels in acute pancreatitis (AP) patients and assess whether MPV effectively predicts the disease severity of AP.

METHODS

We included 117 consecutive patients with AP as the AP group and 34 consecutive patients with colorectal polyps (before endoscopic treatment) as the control group. Complete blood counts, liver function, platelet indices (MPV), coagulation parameters, lactate dehydrogenase (LDH) and C-reactive protein (CRP) were measured on days 1, 2, 3 and 7 after admission. Receiver operating characteristic curves were used to compare the sensitivity and specificity of MPV, white blood cell (WBC), LDH and CRP in predicting AP severity. The Modified Glasgow Prognostic Score (mGPS) and the 2012 revised Atlanta criteria were used to evaluate disease severity in AP.

RESULTS

MPV levels were significantly lower in the AP group than in the control group on day 1 (P = 0.000), day 2 (P = 0.029) and day 3 (P = 0.001) after admission. In addition, MPV values were lower on day 1 after admission than on day 2 (P = 0.012), day 3 (P = 0.000) and day 7 (P = 0.002) in all AP patients. Based on the mGPS, 78 patients (66.7%) were diagnosed with mild and 39 patients (33.3%) with severe AP. There was no significant difference in mean MPV levels between patients diagnosed with mild and severe AP based on the mGPS (P = 0.424). According to the 2012 revised Atlanta criteria, there were 98 patients (83.8%) without persistent organ failure (OF) [non-severe acute pancreatitis (non-SAP) group] and 19 patients (16.2%) with persistent OF (SAP group). MPV levels were significantly lower in the SAP group than in the non-SAP group on day 1 after admission (P = 0.002). On day 1 after admission using a cut-off value of 6.65 fL, the overall accuracy of MPV for predicting SAP according to the 2012 revised Atlanta criteria (AUC = 0.716) had a sensitivity of 91.8% and a specificity of 47.4% and was superior to the accuracy of the traditional markers WBC (AUC = 0.700) and LDH (AUC = 0.697).

CONCLUSION

MPV can be used at no additional cost as a useful, non-invasive biomarker that distinguishes AP with persistent OF from AP without persistent OF on day 1 of hospital admission.

The use of platelet indices, plateletcrit, mean platelet volume and platelet distribution width in emergency non-traumatic abdominal surgery: a systematic review

Platelet indices (PI) -- plateletcrit, mean platelet volume (MPV) and platelet distribution width (PDW) -- are a group of derived platelet parameters obtained as a part of the automatic complete blood count. Emerging evidence suggests that PIs may have diagnostic and prognostic value in certain diseases. This study aimed to summarize the current scientific knowledge on the potential role of PIs as a diagnostic and prognostic marker in patients having emergency, non-traumatic abdominal surgery. In December 2015, we searched Medline/PubMed, Scopus and Google Scholar to identify all articles on PIs. Overall, considerable evidence suggests that PIs are altered with acute appendicitis. Although the role of PI in the differential diagnosis of acute abdomen remains uncertain, low MPV might be useful in acute appendicitis and acute mesenteric ischemia, with high MPV predicting poor prognosis in acute mesenteric ischemia. The current lack of consistency and technical standards in studies involving PIs should be regarded as a serious limitation to comparing these studies. Further large, multicentre prospective studies concurrently collecting data from different ethnicities and genders are needed before they can be used in routine clinical practice.