hsCRP ,basophil count and MPV
Based on the scale of disease severity, 41 of 98 patients with CSU were evaluated as severe, 57 as moderate and mild. Patients with severe urticaria displayed significantly higher levels of hsCRP and MPV than patients with moderate and mild disease(p<0.0001; Fig 2 and Table 2). Patients with severe urticaria displayed significantly lower levels of basophil count than patients with moderate and mild disease(p=0.0008;Fig 2 and Table 2).
Relationship among levels of whole blood hsCRP ,basophil count and MPV
HsCRP were positively correlated with MPV (r=0.6733,p<0.0001),there were significant negatively correlations between basophil count and hsCRP concentrations (r=-0.6720,p<0.0001;Fig 3),and MPV were negatively correlated with basophil count (r=-0.6723,p<0.0001;Fig 3).
Discussion
In this study, significant differences were found in hsCRP, basophil count and MPV between CSU patients and the controls,which supports the assumption that chronic low-grade inflammation and platelet activation are present in CSU15,16. One possible reason for the reduced number of basophils in CSU is that these cells are actively recruited into lesional skin. In the presence of IL-3,chemotaxis is selectively enhanced in basophils by transendothelial migration17.The presence of larger platelets in patients might be a consequence of platelets’ consumption at the site of the urticarial wheals and further compensatory thrombopoiesis18.
Previous studies found a significant association between CSU severity and blood levels of CRP19.Ohtsuka T. found that basopenia and high disease activity may be interlinked.Besides a significant positive correlation between CU severity score and MPV in ASST-positive patients was observed by Magen et al. 18. The present findings are consistent with previous studies.Based on large study it has been indicated that CRP, basophil count and MPV may serve as biomarkers to monitor CSU severity. In addition, We found a positive or negative correlation between these markers, likely reflecting the potential interplay between inflammatory process and platelet activation in CSU.
It is known that CRP increased due to mast cell activation accompanied by inflammatory response20. MPV levels correlated with hsCRP concentration, probably reflecting the same characteristic of the inflammatory response in CSU.It suggests that there is an interrelation between the platelets activation and the inflammatory state in the pathogenesis of CSU. Prior studies have consistently demonstrated that basophils play a crucial role in IgE-dependent chronic allergic inflammation in the skin21John A. Eckman et al. have found altered basophil IgE receptor function in CSU 22. Moreover,some other studies pointed that platelet activation may occur during immunoglobulin E antibody(1gE)-mediated reactions. Stimulated basophils release preformed histamine, the major mediator of urticaria, and newly synthesized factors, such as leukotriene C4 and interleukin (IL)-4 and IL-1323. Histamine potentiates platelet activity measured by the aggregation induced by different agonists, acting through histamine receptors16. Therefore, we suggest that the underlying mechanism for this higher activity of platelets may result from local and/or systemic inflammatory response in CSU.
On the other hand,platelets have been described as a source of inflammatory mediators that are implicated in histamine release from basophil and mast cells16.Some studies confirm that platelet-derived supernatants (PDS) induce histamine release from human mixed leukocytes containing basophils, one of the initial target cells in IgE-mediated reactions. Platelets, once activated,can produce a soluble substance or substances which can initiate basophil-mediated reactions,further suggesting that platelet activation can enhance inflammatory reactions24. Interestingly, data from experimental studies prove that platelet factor-4 (PF-4) fragment is able to induce rat mast cells to release histamine in a dose-dependent manner.Moreover, it has been shown that histamine is released by human platelets in response to aggregatory and immunological stimuli.
Considering the fact that serum histamine-releasing activity is an important determinant for urticarial severity,it seems that CSU patients should be intensively treated to ensure comprehensive control of their symptoms and to reduce inflammatory process and platelet activation.So it is important to perform repeated blood analyses after symptomatic treatment and CSU remission. Sequential assessments of HsCRP, basophil and MPV concentrations, related to severity of CSU might provide stronger evidence of a causal relationship between platelet activation and inflammation.Therefore, more research is required to prove such hypothesis.The analysis of hsCRP, basophil count and MPV is rapid and inexpensive, therefore combining measurement may be a logical and practical tool to improve monitoring of CSU severity in patients with low compliance.
To the best of our knowledge, this study is the first prospective report of the correlation among hsCRP,MPV and basophil count. However, the limitation of the study was that biomarkers concentration all remain within the normal range due to fewer cases. Some improvements may be brought through increasing the number of patients.
In conclusion,markers of inflammatory process (CRP and basophil count) and of platelet activation (MPV) are related to each other in CSU patients, suggesting the possible interaction between these markers in the disease. There may be an interplay between inflammatory process and platelet activation in the pathogenesis of CSU.
The correlation between hsCRP,basophil count and MPV would enable evaluation of the effectiveness of medicines and comparing results of various clinical or epidemiological studies.In addition,further study is needed in order to verify the contribution of biomarkers to the pathological etiology of CSU. Long-term prospective studies are needed to confirm whether this also correlates with disease course.