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The Effect of Platelet Functions on the Hemorrhagic Manifestations and the Mortality
in Crimean-Congo Hemorrhagic Fever
Abstract
Objectives: Crimean-Congo hemorrhagic fever (CCHF) is a viral zoonotic disease which may
be life-threatening with hemorrhagic manifestations. We aimed here in this study to evaluate
the influence of platelet count and volume-related indices, such as mean platelet volume
(MPV), platelet distribution width (PDW) which is a measure of platelet anisocytosis and
plateletcrit, in the hemorrhagic manifestations and the mortality seen in CCHF.
Methods: The age, gender, ALT, AST, platelet counts, MPV, PDW and plateletcrit values,
bleeding manifestations and the mortality status of 173 patients diagnosed with CCHF were
recorded.
Results: In the patient group with observed bleeding, ALT and AST values were measured to
be increased (p<0.01), while Platelet1, Platelet2, PCT1, PCT2 and PDW2 values being low
(p<0.01). A negative correlation was documented between bleeding and Platelet1, Platelet2,
PCT1, PCT2 and PDW2 (r=-0.255, r=-0.415, r=-0.241, r=-0.377, r=-0.223, respectively;
whereas a positive correlation existed between bleeding and mortality (r=0.34).
Higher levels of AST and ALT (p=0.001 and p<0.001, respectively), and lower values of
platelet1, platelet2, PCT1, PCT2, PDW2 (p=0.005, p<0.001, p<0.001, p=0.001, p<0.001,
p=0.015, respectively) were detected in the patients in whom mortality occurred, compared to
the recovered patients.
Discussion: In this study evaluating for the first time the platelet functions in CCHF, the
values, such as PDW and plateletcrit, along with platelet counts were revealed to be correlated
with the mortality and hemorrhagic manifestations.
Key words: Crimean-Congo hemorrhagic fever, platelet, mean platelet volume, platelet
distribution width, plateletcrit.
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1. Objectives
Crimean- Congo hemorrhagic fever (CCHF) is a disease state caused by nairoviruses
of Bunyaviridea family, which is transmitted by bite of the ticks of hyalomma marginatum
species or by direct contact to infected blood or body secretions. The most common clinical
signs of CCHF are fever, nausea, headache, diarrhea, myalgia, petechial rash and bleeding 1.
Mortality rates for the various CCHF epidemics and outbreaks have varied greatly.
The average mortality rate is often cited at 5–50% 2–4.
The diagnosis is established through immunologic methods, PCR-PT or virus isolation
in the cell culture 5.
Infectious diseases lead to bleeding manifestations by means of a constellation of
mechanisms, such as induction of thrombocytopenia, depletion of local clotting factors,
hyperfibrinolysis and leakage secondary to damage to vessel wall 6. However, the exact
underlying pathogenesis behind mothality and bleeding in CCHF has yet to be conspicuously
understood.
All the studies related to CCHF announced trombocytopenia, elevated levels of ALT
and AST, and prolonged aPTT as ominous prognostic indicators. However, the previous
studies yielded distinct findings about the contributions of leukocytosis, LDH, CPK, age and
fibrinogen level in the regard of ominous prognosis 6–8.
The platelets play role primarily in the hemostasis; however, previous studies
documented the platelets constituted and important component of the immune system.
Accordingly, platelets contribute to immune system through various mechanisms, such as
engulfing foreign particles, giving off distinctive adhesion molecules, undergoing chemotaxis,
triggering complement factors and establishing interaction with microorganisms. Platelet
functions can be analyzed based on mean platelet volume (MPV), platelet distribution width
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(PDW) which is a measure of platelet anisocytosis, and plateletcrit (PCT), equivalent of
hematocrit in regard to platelets 9.
Besides that thrombocytopenia has been known to be an poor prognostic indicator, the
disease may still pursue a mortal course, despite presence of adequate number of platelets.
This issue propelled us to consider that platelet function may provide as curial contribution as
platelet count. The aim of the present study was to evaluate the effect of platelet count (PLT)
and volume-related indices, such as MPV, PCT and PDW, in the hemorrhagic manifestations
and the mortality seen in CCHF.
2. Methods
The patients who had been admitted with the complaints of fever, anorexia, weakness,
petechial rash and bleeding to Tokat State Hospital between April 2011 - September 2011
were hospitalized with the prediagnosis of CCHF, no matter a suspected contact to ticks
present or not. The serum samples of the patients were sent for further analysis to National
Reference Laboratory. The patients with PCR and/or IgM positivity suggestive of CCHF were
diagnosed with CCHF.
Platelet function was analyzed by the Beckman Coulter® automated blood cell counter.
MPV, PDW and PCT values on admission (MPV1, PDW1 and PCT1) and those
values measured at the time when platelets count was observed to be at the lowest level
(MPV2, PDW2 and PCT2) were recorded in all the patients. Hemorrhagic manifestations,
such as epistaxis, vaginal or gastrointestinal bleedings, hematuria etc. were also recorded.
2.1 Statistical Analysis
The categorical variables given in counts and percentages in this study were compared
between the groups using Pearson’s chi-square test. Normally-distributing variables were
identified using the Kolmogorov-Smirnov test. Continuous variables presented here in mean
or median (interquartile range [IQR]) were compared between the two groups using the two
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independent sample t test or Mann Whitney U test. A P < 0.05 was accepted to imply
statistical significance.
ROC analysis was utilized in order to specify the thresholds associated with the
laboratory values with regard to their effect on mortality and hemorrhagic manifestations.
SPSS software 17.0 for Windows (Chicago, IL, USA) was used for all statistical analysis.
3. Results
We enrolled a total of 173 patients (83 males, 90 females; 47.9% and 52.1%,
respectively) in the study. Hemorrhaging was observed in 13.8 % (24) during hospitalization.
When we evaluated hemorrhaging with regard to the gender of the study participitans
WBC1, WBC2, MPV1, MPV2 and PDW1 values were found to be similar between the
hemorrhagic patients and those without hemorrhagic patients (p>0.05).
In addition, there were significantly higher ALT and AST values among hemorrhagic
patients compared to the others; p<0.001 and p<0.001 respectively.
When we evaluated Platelet1, Platelet2, PCT1, PCT2 and PDW2 values, were
significantly lower (p=0.001, p<0.001, p=0.002, p<0.001, p=0.003) with hemorrhagic patients
than non hemorrhagic patients. Laboratory values compared by demographic and clinical
features are given in table 1. Higher levels of AST and ALT (p=0.001 and p<0.001,
respectively), and lower values of platelet, PCT, PDW (p<0.001, p<0.001, p=0.003
respectively) were detected in the patients in whom mortality occurred, compared to the
recovered patients.
The lower threshold for PCT1; and PCT2 were determined to be ≤ 0.02 (PCT1
sensitivity: 37.5%, specificity: 92.6%; PCT2 sensitivity: 92.3%, specificity: 82.4%). PCT2 as
shown in Figure 1.
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A negative correlation was documented between bleeding and Platelet1, Platelet2,
PCT1, PCT2 and PDW2 (r=-0.255, r=-0.415, r=-0.241, r=-0.377, r=-0.223, respectively;
whereas a positive correlation existed between bleeding and mortality (r=0.34).
Figure 2 exhibits the correlation of the PCT value with bleeding and mortality.
4. Discussion
The values, such as PDW and PCT, along with platelet counts were revealed by this
study, the first one ever evaluating the platelet functions in CCHF to be correlated with the
mortality and hemorrhagic manifestations.
Thrombocytopenia is a significant marker used both in the diagnosis and follow-up.
WBC and platelet counts should be paid a special attention in complete blood count test
performed in the diagnosis and during follow-up period. The platelet count < 20X109/micro
liter was reported to be an indicator of poor prognosis 6,9.
Yilmaz et al. found that PDW is a parameter that may be used to determine disease
severity 9. Onguru et al. evaluated the correlation of mortality of CCHF with coagulationrelated parameters, such as protein S, protein C, anti-thrombin III, APCR, and D-dimer.
Reporting no correlation in the former regard, they announced the existence of an association
between mortality and the parameters, such as platelet count, PT, aPTT, INR, and fibrinogen
levels, and that the traditional coagulation parameters were sufficient to be monitored in the
diagnosis and during the follow-up 10.
There are three major components within hemostasis; ‘primary hemostasis’,
‘secondary hemostasis’ and ‘fibrinolysis’ 11. Primer hemostasis can be evaluated via complete
or full blood count, a test to provide data regarding platelets' total count, volume, morphology
and maturity were measured
11,12
. Modern blood counters are eligible for rapid measurement
of the parameters, such as MPV, PDW and PCT.
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A sizable number of compounds contributing to inflammation, coagulation,
thrombosis and atherosclerosis were secreted from the activated platelets, including
chemokines, cytokines and coagulation factors. Previous clinical trials indicated the platelets
to be a pivotal component in the evaluation of inflammatory response. The aforementioned
factors play role in aggregation, adhesion and thrombus generation
13
. The volume of the
platelets increases upon their activation. Larger platelets have been documented to possess
thrombotic potential and to induce inflammatory processes 14.
Platelet size is dictated by progenitor cells, such as megakaryocyte. There are some
studies suggesting that cytokines such as interleukin 3 (IL-3) and interleukin 6(IL-6) stimulate
the megakaryocyte at the chromosomal level, thus augmenting the production of much more
reactive and voluminous platelets
15
. Mean platelet volume (MPV) indicates platelet
activation. Moreover, it is also an important marker predicting the platelets’ function,
morphology and maturity. MPV is provided within the CBC test, inflicting no further cost for
measurement 16.
MPV level was shown to increase during inflammatory disease states like ankylosing
spondylitis, rheumatoid arthritis, and infectious diseases like pulmonary tuberculosis 17,18.
We found normal levels of MPV in the patients with CCHF. MPV, which increase in
thrombotic states, would be anticipated to decrease in such disease state as CCHF
characterized by thrombocytosis. However, MPV was documented to increase in
inflammatory and infectious diseases. We considered at this point that the former two
opposite issues related to CCHF, an infectious disease characterized by thrombocytopenia,
cancelled each other, sustaining MPV in normal range.
The limit at which platelet transfusion should be commenced remains to be elucidated.
Our clinical experiences yield conflicting data, ranging from cases of bleeding with platelets
count > 50.000 to some others with platelet count < 20.000, but without any overt bleeding.
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Representing a more precious indicator in terms of bleeding risk compared to platelet count,
PCT value < 0.1% dictates implementation of thrombocyte transfusion 19.
The present study found correlation between the decreasing PTC, and bleeding and
mortality during the follow-up of CCHF. We consider that PCT value may prove useful in
anticipation of the timing of platelet transfusion in patients with CCHF. Similar to the concept
of erythrocyte distribution range, PDW represents an index indicating heterogeneity of
platelet volumes. Evaluation of PWD along with MPV provides better estimation of platelet
volume distribution. PDW was shown to be greater in patients with activated platelets,
compared with healthy subjects 20.
PDW, similar to MPV, was reported to increase in patients with platelet activation
compared with healthy subjects. Moreover, it was suggested that PDW acted more
specifically in predicting thrombocyte activation, compared to MPV. On the contrary, MPV
and PDW are generally measured to be at the lower limits during thrombocytopenia states
caused by bone marrow failure. We consider that use of MPV and PDW in combination is
likely to yield more accurate prediction of coagulation activation 21.
MPV levels were found to be normal in this study. PDW values measured on
admission were normal, whereas the levels measured at the time the lowest platelet count
(PDW2) were found to be lower. Decrease in PDW, measured to be normal at the onset of the
disease, in a parallel manner to deterioration of the disease suggests that PDW2 may be
associated with bleeding and mortality, and that it can be used as a prognostic indicator during
the follow-up of the disease.
Bleeding is one of the important reasons for mortality in Crimean-Congo Hemorrhagic
Fever. The platelet functions contribute as much extent to prediction of bleeding and mortality
as the platelet count.
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The present study suggests that PCT and PDW values could be beneficial in
anticipating the inclination toward bleeding and mortality, beginning from the onset of the
disease and from the time when platelet counts commence to decrease, respectively.
We suggest that parameters like PCT and PDW, included in CBC test without
infliction of any additional cost to measure, may be utilized in the follow-up of the patients
and that further various studies are likely to elucidate this issue.
Conflict of interests: None to declare
Funding: This research did not receive any specific grant from funding agencies in the
public, commercial, or not-for-profit sectors.
Acknowledgments: We acknowledge the contributions of all research team members who
have played crucial role in data acquisition. Each author has contributed important intellectual
content during manuscript drafting or revision. The authors declare that there is no conflict of
interests.
References:
1.
Drosten C, Minnak D, Emmerich P, Schmitz H, Reinicke T. Crimean-Congo
hemorrhagic fever in Kosovo. J Clin Microbiol. Mart 2002;40(3):1122–3.
2.
Hoogstraal H. The epidemiology of tick-borne Crimean-Congo hemorrhagic fever in
Asia, Europe, and Africa. J Med Entomol. 22 Mayıs 1979;15(4):307–417.
3.
Nichol, S.T. Bunyaviruses. Içinde: Lippincott, Williams & Wilkins, Philadelphia. Knipe,
D.M., Howley, P.M. (Eds.); 2001. s. 1603–33.
4.
Whitehouse CA. Crimean-Congo hemorrhagic fever. Antiviral Res. Aralık
2004;64(3):145–60.
5.
van Gorp EC, Suharti C, ten Cate H, Dolmans WM, van der Meer JW, ten Cate JW, vd.
Review: infectious diseases and coagulation disorders. J Infect Dis. Temmuz
1999;180(1):176–86.
6.
Cevik MA, Erbay A, Bodur H, Gülderen E, Baştuğ A, Kubar A, vd. Clinical and
laboratory features of Crimean-Congo hemorrhagic fever: predictors of fatality. Int J
Infect Dis IJID Off Publ Int Soc Infect Dis. Temmuz 2008;12(4):374–9.
7.
Hatipoglu CA, Bulut C, Yetkin MA, Ertem GT, Erdinc FS, Kilic EK, vd. Evaluation of
clinical and laboratory predictors of fatality in patients with Crimean-Congo
8
haemorrhagic fever in a tertiary care hospital in Turkey. Scand J Infect Dis. Temmuz
2010;42(6–7):516–21.
8.
Yesilyurt M, Gul S, Ozturk B, Kayhan BC, Celik M, Uyar C, vd. The early prediction of
fatality in Crimean Congo hemorrhagic fever patients. Saudi Med J. Temmuz
2011;32(7):742–3.
9.
Yilmaz H, Yilmaz G, Menteşe A, Kostakoğlu U, Karahan SC, Köksal İ. Prognostic
impact of platelet distribution width in patients with Crimean-Congo hemorrhagic fever.
J Med Virol. Kasım 2016;88(11):1862–6.
10. Onguru P, Dagdas S, Bodur H, Yilmaz M, Akinci E, Eren S, vd. Coagulopathy
parameters in patients with Crimean-Congo hemorrhagic fever and its relation with
mortality. J Clin Lab Anal. 2010;24(3):163–6.
11. Lippi G, Favaloro EJ, Franchini M, Guidi GC. Milestones and perspectives in
coagulation and hemostasis. Semin Thromb Hemost. Şubat 2009;35(1):9–22.
12. Harrison P, Goodall AH. “Message in the platelet”--more than just vestigial mRNA!
Platelets. Eylül 2008;19(6):395–404.
13. Coppinger JA, Cagney G, Toomey S, Kislinger T, Belton O, McRedmond JP, vd.
Characterization of the proteins released from activated platelets leads to localization of
novel platelet proteins in human atherosclerotic lesions. Blood. 15 Mart
2004;103(6):2096–104.
14. Bath PM, Butterworth RJ. Platelet size: measurement, physiology and vascular disease.
Blood Coagul Fibrinolysis Int J Haemost Thromb. Mart 1996;7(2):157–61.
15. Debili N, Massé JM, Katz A, Guichard J, Breton-Gorius J, Vainchenker W. Effects of
the recombinant hematopoietic growth factors interleukin-3, interleukin-6, stem cell
factor, and leukemia inhibitory factor on the megakaryocytic differentiation of CD34+
cells. Blood. 01 Temmuz 1993;82(1):84–95.
16. Thompson CB, Jakubowski JA, Quinn PG, Deykin D, Valeri CR. Platelet size and age
determine platelet function independently. Blood. Haziran 1984;63(6):1372–5.
17. Kisacik B, Tufan A, Kalyoncu U, Karadag O, Akdogan A, Ozturk MA, vd. Mean
platelet volume (MPV) as an inflammatory marker in ankylosing spondylitis and
rheumatoid arthritis. Jt Bone Spine Rev Rhum. Mayıs 2008;75(3):291–4.
18. Tozkoparan E, Deniz O, Ucar E, Bilgic H, Ekiz K. Changes in platelet count and indices
in pulmonary tuberculosis. Clin Chem Lab Med. 2007;45(8):1009–13.
19. Mohr R, Martinowitz U, Golan M, Ayala L, Goor DA, Ramot B. Platelet size and mass
as an indicator for platelet transfusion after cardiopulmonary bypass. Circulation. Kasım
1986;74(5 Pt 2):III153-158.
20. Vagdatli E, Gounari E, Lazaridou E, Katsibourlia E, Tsikopoulou F, Labrianou I.
Platelet distribution width: a simple, practical and specific marker of activation of
coagulation. Hippokratia. Ocak 2010;14(1):28–32.
9
21. Jackson SR, Carter JM. Platelet volume: laboratory measurement and clinical
application. Blood Rev. Haziran 1993;7(2):104–13.
Table I. Comparison of demographic characteristics and laboratory values of
bleeding patients and without bleeding patients
Figure 1. ROC analyses on PCT2 and mortality
Figure 2. Mean PCT values in patients
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