Can d-dimer become a new diagnostic parameter for acute appendicitis?

Diagnostic efficacy of serum procalcitonin, IL-6, IL-2, and D-dimer levels in an experimental acute appendicitis model

BACKGROUND/AIMS

Acute appendicitis is the most frequent cause of acute abdomen emergency surgery. It continues to be a problem today due to delayed diagnosis and its high perforation rate. For this reason, diagnostic tests continue to be developed. In this experimental study, the diagnostic significance of blood procalcitonin (PCT), interleukin (IL)-6, IL-2, and D-dimer levels in an acute appendicitis model in rabbits was investigated.

MATERIALS AND METHODS

A total of five groups were included: control group, sham group, and three different acute appendicitis groups. In the appendicitis groups, the appendix was ligated by laparotomy, and the blood PCT, IL-6, IL-2, and D-dimer levels were measured at 12 (group 3), 24 (group 4), and 48 h (group 5). Then, an appendectomy was performed.

RESULTS

In the present study, PCT and IL-6 levels increased in parallel with the inflammation of the appendix in all groups and were found to be statistically significant. IL-2 and D-dimer values were higher in the groups diagnosed with appendicitis but were not statistically significant.

CONCLUSION

In our experimental study, PCT and IL-6 levels were determined to be important in the early diagnosis of acute appendicitis, especially IL-6, and that these two parameters are more important markers than IL-2 and D-dimer.

The vermiform appendix impacts the risk of developing Parkinson's disease

The pathogenesis of Parkinson's disease (PD) involves the accumulation of aggregated α-synuclein, which has been suggested to begin in the gastrointestinal tract. Here, we determined the capacity of the appendix to modify PD risk and influence pathogenesis. In two independent epidemiological datasets, involving more than 1.6 million individuals and over 91 million person-years, we observed that removal of the appendix decades before PD onset was associated with a lower risk for PD, particularly for individuals living in rural areas, and delayed the age of PD onset. We also found that the healthy human appendix contained intraneuronal α-synuclein aggregates and an abundance of PD pathology-associated α-synuclein truncation products that are known to accumulate in Lewy bodies, the pathological hallmark of PD. Lysates of human appendix tissue induced the rapid cleavage and oligomerization of full-length recombinant α-synuclein. Together, we propose that the normal human appendix contains pathogenic forms of α-synuclein that affect the risk of developing PD.

The Role of Ultrasonography in Patients Referring to the Emergency Department with Acute Abdominal Pain

CONTEXT

Acute abdominal pain is a common clinical problem in emergency and non-emergency cases accounting for 5 to 10% of all referrals to the emergency department. Studies have indicated that these widely differentiated diagnoses are common to these complaints. Considering the high prevalence of this complaint in the patients and the wide range of its differential diagnosis, this review study was designed and evaluated aiming at investigating the causes of acute abdominal pain with a focus on assessing the position of ultrasound as a diagnostic tool in the emergency department.

EVIDENCE ACQUISITION

This article was conducted as a narrative review of selected articles from 2005 through 2019. By comparing them, a comprehensive review of ultrasound role was conducted in patients with acute abdominal pain referring to the emergency department.

RESULTS

In this review study, we attempted to use the articles of the clinical approach, the required laboratory tests, the disadvantages and advantages of each imaging technique, the differential diagnosis for acute abdominal pain according to the location of the pain, and the position of ultrasound as a diagnostic aid tool. Eventually, the proposed protrusion will be considered in dealing with a patient with acute abdominal pain.

CONCLUSION

Regarding the wide range of causes providing multiple differential diagnosis, as well as the limited time of the health team in the emergency department for diagnostic and therapeutic measures, particularly in time-sensitive clinical conditions, ultrasound offered by emergency medicine specialists as a diagnostic aid is considered to improve the overall diagnosis and treatment of patients, thereby reducing complications.

Diagnostic accuracy and prognostic utility of D Dimer in acute appendicitis in children

The objective was to determine the uselfulness of D Dimer (DD) as a diagnostic or prognostic marker in acute appendicitis (AA) in children using a prospective observational study in the pediatric emergency department of a tertiary hospital. We enrolled 135 patients aged 1-16 years presenting with abdominal pain consistent with AA, who required laboratory studies. We analyzed clinical, analytical variables and histopathology findings (when they underwent surgery). Statistical analysis was conducted using SPSS. 38.5% of the children were clinically diagnosed with AA (n = 52), confirmed by pathology in 51 patients. 55.8% were gangrenous appendicitis. Leucocyte count, C-reactive protein (CRP), and DD were higher in the AA group and in the gangrenous appendicitis group (p < 0.05), with highest values of DD in the gangrenous group. The area under the receiving operating characteristics (ROC) curve for DD in the diagnosis of AA is 0.66 (95% CI 0.56-0.75). For DD cut-off point of 230 ng/mL, sensitivity (Se) was 0.40, specificity (Sp) 0.80, positive predictive value (PPV) 0.57, and negative predictive value (NPV) 0.66. The area under the ROC curve for DD in children with gangrenous appendicitis is 0.93 (95% CI 0.87-1). A DD cut-off point of 230 ng/mL exhibited: Se = 0.69, Sp = 1, PPV = 1 and NPV = 0.72.

CONCLUSION

DD levels increase in patients with AA. Although it does not constitute a useful diagnostic marker, it could be a good prognostic marker.

The diagnostic value of D-dimer, procalcitonin and CRP in acute appendicitis

BACKGROUND

The early diagnosis of acute abdomen is of great importance. To date, several inflammatory markers have been used for the diagnosis of acute abdominal conditions, including acute appendicitis. The aim of this study was to evaluate the diagnostic utility of D-dimer, Procalcitonin (PCT) and C-reactive protein (CRP) measurements in the acute appendicitis.

METHODS

This prospective study was conducted between March 1(st), 2010 and July 1(st), 2011. In this period, seventy-eight patients were operated with the diagnosis of acute appendicitis, and D-dimer, PCT and CRP levels of the patients were measured. The patients were grouped as phlegmonous appendicitis (Group 1), gangrenous appendicitis (Group 2), perforated appendicitis (Group 3) and negative appendectomy (Group 4) according to the surgical findings and histopathological results.

RESULTS

Of 78 patients, 54 (69.2 %) were male and 24 (30.8 %) were female, and the mean age was 25.4 ± 11.1 years (range, 18 to 69 years). 66 (84.6 %) patients had increased leukocyte count (white blood cell count). The PCT values were higher than the upper normal limit in 20 (25.6%) patients, followed by D-dimer in 22 (28.2 %) patients and CRP in 54 (69.2 %) patients. The diagnostic value of leukocyte count and CRP in acute appendicitis was higher than that of the other markers, whereas leukocyte count showed very low specificity. CRP values were higher in perforated appendicitis when compared with the phlegmonous appendicitis (p < 0.05). However, PCT and D-dimer showed lower diagnostic values (26% and 31%, respectively).

CONCLUSION

An increase in CRP levels alone is not sufficient to make the diagnosis of acute appendicitis. However, CRP levels may differentiate between phlegmonous appendicitis and perforated appendicitis. Due to their low sensitivity and diagnostic value, PCT and D-dimer are not better markers than CRP for the diagnosis of acute appendicitis.

Diagnostic characteristics of S100A8/A9 in a multicenter study of patients with acute right lower quadrant abdominal pain

OBJECTIVES

Over the past decade, clinicians have become increasingly reliant on computed tomography (CT) for the evaluation of patients with suspected acute appendicitis. To limit the radiation risks and costs of CT, investigators have searched for biomarkers to aid in diagnostic decision-making. We evaluated one such biomarker, calprotectin or S100A8/A9, and determined the diagnostic performance characteristics of a developmental biomarker assay in a multicenter investigation of patients presenting with acute right lower quadrant abdominal pain.

METHODS

This was a prospective, double-blinded, single-arm, multicenter investigation performed in 13 emergency departments (EDs) from August 2009 to April 2010 of patients presenting with acute right lower quadrant abdominal pain. Plasma samples were tested using the investigational S100A8/A9 assay. The primary outcome of acute appendicitis was determined by histopathology for patients undergoing appendectomy or 2-week telephone follow-up for patients discharged without surgery. The sensitivity, specificity, negative likelihood ratio (LR-), and positive likelihood ratio (LR+) of the biomarker assay were calculated using the prespecified cutoff value of 14 units. A post hoc stability study was performed to investigate the potential effect of time and courier transport on the measured value of the S100A8/A9 assay test results.

RESULTS

Of 1,052 enrolled patients, 848 met criteria for analysis. The median age was 24.5 years (interquartile range [IQR] = 16-38 years), 57% were female, and 50% were white. There was a 27.5% prevalence of acute appendicitis. The sensitivity and specificity for the investigational S100A8/A9 assay in diagnosing acute appendicitis were estimated to be 96% (95% confidence interval [CI] = 93% to 98%) and 16% (95% CI = 13% to 19%), respectively. The LR- ratio was 0.24 (95% CI = 0.12 to 0.47), and the LR+ was 1.14 (95% CI = 1.10 to 1.19). The post hoc stability study demonstrated that in the samples that were shipped, the estimated time coefficient was 7.6 × 10(-3) ± 2.0 × 10(-3) log units/hour, representing an average increase of 43% in the measured value over 48 hours; in the samples that were not shipped, the estimated time coefficient was 2.5 × 10(-3) ± 0.4 × 10(-3) log units/hour, representing a 13% increase on average in the measured value over 48 hours, which was the maximum delay allowed by the study protocol. Thus, adjusting the cutoff value of 14 units by the magnitude of systematic inflation observed in the stability study at 48 hours would result in a new cutoff value of 20 units and a "corrected" sensitivity and specificity of 91 and 28%, respectively.

CONCLUSIONS

In patients presenting with acute right lower quadrant abdominal pain, we found the investigational enzyme-linked immunosorbent assay (ELISA) test for S100A8/A9 to perform with high sensitivity but very limited specificity. We found that shipping effect and delay in analysis resulted in a subsequent rise in test values, thereby increasing the sensitivity and decreasing the specificity of the test. Further investigation with hospital-based laboratory analyzers is the next critical step for determining the ultimate clinical utility of the ELISA test for S100A8/A9 in ED patients presenting with acute right lower quadrant abdominal pain.