Analyze Diet
Parasite epidemiology and control2025; 30; e00453; doi: 10.1016/j.parepi.2025.e00453

The use of systemic immune inflammatory index as a predictor for nematodes infections in horses.

Abstract: Nematode infections are a significant health concern in horses, causing a range of clinical signs and economic losses. Early detection and diagnosis are crucial for effective treatment and management. Unassigned: Examining the application of the systemic immune Inflammatory index (SII) as a predictor for nematode infections in horses, using platelets count, leucocytes count, and neutrophils count. Unassigned: A cross-sectional study was conducted on 164 horses, consisting of 66 horses with nematode infections and 98 horses without infections. The SII was computed using the platelets count, leucocytes count, and neutrophils count. Receiver operating characteristic (ROC) curve analysis was used to evaluate the SII's diagnostic accuracy. Unassigned: Nematode infections were severe in horses with mixed infections, with an average of 1805.90 ± 292.68 eggs per gram (epg). Notably, among specific species, spp., exhibited a significantly different average of 2264.29 ± 132.61epg compared to other nematodes. There is a significant negative correlations between the systemic immune-inflammatory index (SII) and the Eggs per gram count for nematodes infections at ( = -0.6023;  < .0001). The SII values were significantly lower (0.06) in horses with nematode infections compared to those without infections (0.19) at  < .001. With an area under the ROC curve (AUC) of 0.990, the SII demonstrated exceptional diagnostic precision. For the SII, the ideal cut-off value is ≤0.108, with a sensitivity of 98.5 % and a specificity of 100 %. The ROC curve was validated using the Youden index (J) with a higher value of 0.9848 indicating better performance. Unassigned: The study demonstrated that the SII is a reliable predictor for nematode infections in horses, using platelets count, leucocytes count, and neutrophils count. The SII is a non-invasive, reasonably priced method for identifying and diagnosing nematode infections in horses.
Publication Date: 2025-07-31 PubMed ID: 40837204PubMed Central: PMC12361788DOI: 10.1016/j.parepi.2025.e00453Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

  • This study investigates the use of the systemic immune-inflammatory index (SII) as a diagnostic tool to predict nematode infections in horses by analyzing blood cell counts.
  • It demonstrates that SII is a highly accurate, non-invasive, and cost-effective biomarker for detecting these infections early.

Background and Importance

  • Nematode infections are common and problematic in horses, leading to various health issues and economic burdens.
  • Effective management of these infections depends on early and accurate diagnosis to allow prompt treatment.
  • Traditional diagnosis relies on fecal egg counts, which can be variable and sometimes not sensitive enough for early detection.
  • The systemic immune-inflammatory index (SII), calculated from routine blood parameters (platelets, leucocytes, and neutrophils), could offer a reliable alternative.

Study Design and Methods

  • A cross-sectional study was conducted involving 164 horses, divided into two groups: 66 horses confirmed with nematode infections and 98 apparently healthy horses without infections.
  • Blood samples were collected to measure platelets count, leucocytes count, and neutrophils count, from which the SII was calculated.
  • The SII calculation integrates these three counts to reflect the systemic immune and inflammatory status of the horse.
  • Fecal samples were analyzed to quantify the intensity of nematode infections through eggs per gram (epg) counts.
  • Receiver operating characteristic (ROC) curve analysis was used to assess the diagnostic accuracy of the SII index in distinguishing infected from non-infected horses.

Key Findings

  • Horses with mixed nematode infections had severe parasite loads, averaging approximately 1805.90 eggs per gram of feces.
  • Some nematode species exhibited significantly higher egg counts, such as one genus with an average of about 2264.29 epg, highlighting variability in infection intensity.
  • A significant negative correlation was found between SII values and nematode egg counts (correlation coefficient = -0.6023, p < 0.0001), indicating that lower SII values correspond to higher parasite loads.
  • Horses infected with nematodes showed significantly lower SII values (mean of 0.06) compared to non-infected horses (mean of 0.19), with a p-value < 0.001 indicating strong statistical significance.
  • The ROC curve analysis yielded an area under the curve (AUC) of 0.990, demonstrating excellent diagnostic accuracy of the SII index.
  • An optimal SII cut-off value of ≤0.108 was identified for predicting infection status.
  • At this cut-off, the SII achieved a sensitivity of 98.5% (correctly identifying infected horses) and a specificity of 100% (correctly identifying non-infected horses), illustrating near-perfect diagnostic performance.
  • The Youden Index (J), a metric combining sensitivity and specificity, was 0.9848, confirming the robust predictive power of SII.

Implications and Conclusion

  • The study validates the systemic immune-inflammatory index as a reliable biomarker for early detection of nematode infections in horses.
  • SII offers a practical diagnostic tool because it is based on routine blood tests that are easy to perform and cost-effective.
  • Because it is minimally invasive compared to some other methods, SII can be conveniently used for regular screening to prevent the progression of nematode infections.
  • Early identification using SII supports timely treatment, which can improve horse health and reduce economic losses related to parasitic infections.
  • The study encourages the incorporation of SII into veterinary diagnostic protocols for better management of equine nematode infections.

Cite This Article

APA
Kyari F, Pogu CJ, Mairiga IA, Adamu L. (2025). The use of systemic immune inflammatory index as a predictor for nematodes infections in horses. Parasite Epidemiol Control, 30, e00453. https://doi.org/10.1016/j.parepi.2025.e00453

Publication

ISSN: 2405-6731
NlmUniqueID: 101687137
Country: Netherlands
Language: English
Volume: 30
Pages: e00453
PII: e00453

Researcher Affiliations

Kyari, Falmata
  • Faculty of Veterinary Medicine, Department of Veterinary Parasitology, University of Maiduguri, Maiduguri P.M.B. 1069, Borno State, Nigeria.
Pogu, Cephas Joseph
  • Faculty of Veterinary Medicine, Department of Veterinary Medicine, University of Maiduguri, Maiduguri P.M.B. 1069, Borno State, Nigeria.
Mairiga, Ismaila Alhaji
  • Faculty of Veterinary Medicine, Department of Veterinary Medicine, University of Maiduguri, Maiduguri P.M.B. 1069, Borno State, Nigeria.
Adamu, Lawan
  • Faculty of Veterinary Medicine, Department of Veterinary Medicine, University of Maiduguri, Maiduguri P.M.B. 1069, Borno State, Nigeria.

Conflict of Interest Statement

No conflicting interest to declare.

References

This article includes 59 references
  1. Abo-Aziza F.A., Hendawy S.H., El Namaky A.H., Ashry H.M.. Th1/Th2 balance and humoral immune response to potential antigens as early diagnostic method of equine Strongylus nematode infection.. Vet. World 2017;10(6):679.
    pmc: PMC5499087pubmed: 28717322
  2. Amulic B., Cazalet C., Hayes G.L., Metzler K.D., Zychlinsky A.. Neutrophil function: from mechanisms to disease.. Annu. Rev. Immunol. 2012;30(1):459–489.
    pubmed: 22224774
  3. Bodis G., Toth V., Schwarting A.. Role of human leukocyte antigens (HLA) in autoimmune diseases.. Rheumatol. Ther. 2018;5:5–20.
    pmc: PMC5935613pubmed: 29516402
  4. Burke J.. Current and future trends in managing internal parasites in forage-based livestock.. Anim. Front. 2024;14(5):3–4.
  5. Candemir M., Kiziltunc E., Nurkoc S., Şahinarslan A.. Relationship between systemic immune-inflammation index (SII) and the severity of stable coronary artery disease.. Angiology 2021;72(6):575–581.
    pubmed: 33685239
  6. Carter J.V., Pan J., Rai S.N., Galandiuk S.. ROC-ing along: evaluation and interpretation of receiver operating characteristic curves.. Surgery 2016;159(6):1638–1645.
    pubmed: 26962006
  7. Cassatella M.A., Östberg N.K., Tamassia N., Soehnlein O.. Biological roles of neutrophil-derived granule proteins and cytokines.. Trends Immunol. 2019;40(7):648–664.
    pubmed: 31155315
  8. Cooper N., Ghanima W.. Immune thrombocytopenia.. N. Engl. J. Med. 2019;381(10):945–955.
    pubmed: 31483965
  9. Cox N., Pokrovskii M., Vicario R., Geissmann F.. Origins, biology, and diseases of tissue macrophages.. Annu. Rev. Immunol. 2021;39(1):313–344.
    pmc: PMC10786183pubmed: 33902313
  10. Dale D.C., Boxer L., Liles W.C.. The phagocytes: neutrophils and monocytes.. Blood 2008;112(4):935–945.
    pubmed: 18684880
  11. Debere D., Muktar Y., Shiferaw S., Belina D.. Internal parasites of equines and associated risk factors in and around Guder town, West Shewa, central Ethiopia.. Ethiopian Vet. J. 2018;22(2):36–52.
  12. Fabricant P.D.. Practical Clinical Research Design and Application: A Primer for Physicians, Surgeons, and Clinical Healthcare Professionals.. Cham; Springer Nature Switzerland: 2024. Characteristics of a diagnostic test: Sensitivity, specificity, positive predictive value, and negative predictive value; pp. 31–36.
  13. Faurschou M., Borregaard N.. Neutrophil granules and secretory vesicles in inflammation.. Microbes Infect. 2003;5(14):1317–1327.
    pubmed: 14613775
  14. Foster N., Elsheikha H.M.. The immune response to parasitic helminths of veterinary importance and its potential manipulation for future vaccine control strategies.. Parasitol. Res. 2012;110:1587–1599.
    pubmed: 22314781
  15. George J.N., Aster R.H.. Drug-induced thrombocytopenia: pathogenesis, evaluation, and management.. ASH Education Program Book 2009;2009(1):153–158.
    pmc: PMC4413903pubmed: 20008194
  16. Germolec D.R., Shipkowski K.A., Frawley R.P., Evans E.. Immunotoxicity Testing: Methods and Protocols. 2018. Markers of inflammation; pp. 57–79.
    pubmed: 29882133
  17. González-Garduño R., Maldonado-Simán E., Torres-Hernández G., Ponce-Covarrubias J.L., Oliva-Hernández J., Gives P.M.D.. Immune and parasitological response in horses infected with gastrointestinal nematodes in the humid tropic of Mexico. Eco. Recur. Agr. 2021;8(1).
  18. Hassanzad M., Hajian-Tilaki K.. Methods of determining optimal cut-point of diagnostic biomarkers with application of clinical data in ROC analysis: an update review. BMC Med. Res. Methodol. 2024;24(1):84.
    pmc: PMC11000303pubmed: 38589814
  19. Hayward C.P.M.. How I investigate for bleeding disorders. Int. J. Lab. Hematol. 2018;40:6–14.
    pubmed: 29741250
  20. Hendrix C.M., Robinson E.D.. Diagnostic Parasitology for Veterinary Technicians-E-Book. Elsevier Health Sciences; 2022.
  21. Islam M.M., Satici M.O., Eroglu S.E.. Unraveling the clinical significance and prognostic value of the neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, systemic immune-inflammation index, systemic inflammation response index, and delta neutrophil index: an extensive literature review. Turk. J. Emerg. Med. 2024;24(1):8–19.
    pmc: PMC10852137pubmed: 38343523
  22. Kaplan R.M., Nielsen M.K.. An evidence-based approach to equine parasite control: it ain’t the 60s anymore. Equine Vet. Educ. 2010;22(6):306–316.
  23. Karakayali M., Omar T., Artac I., Rencuzogullari I., Karabag Y., Demir O.. The relationship between the systemic immune-inflammation index and reverse-dipper circadian pattern in newly diagnosed hypertensive patients. J. Clin. Hypertens. 2023;25(8):700–707.
    pmc: PMC10423764pubmed: 37464585
  24. Karakayali M., Altunova M., Yakisan T., Aslan S., Omar T., Artac I., Ilis D., Arslan A., Cagin Z., Karabag Y., Rencuzogullari I.. The relationship between the systemic immune-inflammation index and ischemia with non-obstructive coronary arteries in patients undergoing coronary angiography. Arq. Bras. Cardiol. 2024;121 p.e20230540.
    pmc: PMC12092018pubmed: 38597536
  25. Khan W.I., Collins S.M.. Immune-mediated alteration in gut physiology and its role in host defence in nematode infection. Parasite Immunol. 2004;26(8–9):319–326.
    pubmed: 15679628
  26. Krofič Žel M., Nemec Svete A., Tozon N., Pavlin D.. Hemogram-derived inflammatory markers in cats with chronic kidney disease. Animals 2024;14(12):1813.
    pmc: PMC11200498pubmed: 38929432
  27. Liu F., Yin P., Jiao B., Shi Z., Qiao F., Xu J.. Detecting the preoperative peripheral blood systemic immune-inflammation index (SII) as a tool for early diagnosis and prognosis of gallbladder cancer. BMC Immunol. 2025;26(1):7.
    pmc: PMC11834489pubmed: 39966731
  28. Lkhagvasuren E.. Janeway’s immunobiology. Central Asian J. Med. Sci. 2017;3(1):100–101.
  29. Mangalesh S., Dudani S., Malik A.. The systemic immune-inflammation index in predicting sepsis mortality. Postgrad. Med. 2023;135(4):345–351.
    pubmed: 36287784
  30. Martínez Barbero J.P., Pérez García F.J., Jiménez Gutiérrez P.M., García Cerezo M., López Cornejo D., Olivares Granados G., Benítez J.M., Láinez Ramos-Bossini A.J.. The value of cerebral blood volume derived from dynamic susceptibility contrast perfusion MRI in predicting IDH mutation status of brain gliomas—a systematic review and meta-analysis. Diagnostics 2025;15(7):896.
    pmc: PMC11989136pubmed: 40218247
  31. Mathewos M, Teshome D, Fesseha H. Study on gastrointestinal nematodes of equines in and around Bekoji, south eastern Ethiopia.. J. Parasitol. Res. 2022;2022(1):8210160.
    pmc: PMC9170501pubmed: 35677390
  32. Matthay M.A., Zemans R.L., Zimmerman G.A., Arabi Y.M., Beitler J.R., Mercat A., Herridge M., Randolph A.G., Calfee C.S.. Acute respiratory distress syndrome.. Nat. Rev. Dis. Primers. 2019;5(1):18.
    pmc: PMC6709677pubmed: 30872586
  33. Matthews J.B., Peczak N., Lightbody K.L.. The use of innovative diagnostics to inform sustainable control of equine helminth infections.. Pathogens 2023;12(10):1233.
    pmc: PMC10610145pubmed: 37887749
  34. Middleton E., Rondina M.T.. Platelets in infectious disease.. Hematology 2014 2016;2016(1):256–261.
    pmc: PMC6142503pubmed: 27913489
  35. Nielsen M.K., Reinemeyer C.R.. Handbook of Equine Parasite Control.. .
  36. Nielsen M.K., Haaning N., Olsen S.N.. Strongyle egg shedding consistency in horses on farms using selective therapy in Denmark.. Vet. Parasitol. 2006;135(3–4):333–335.
    pubmed: 16226379
  37. Oflar E., Akdeniz E., Yıldız C., Koyuncu A., Mavi B., Karabulut D., Çağlar F.N.T., Kavala A.A., Türkyılmaz S.. Evaluation of systemic immune-inflammation index for predicting severity of lower extremity arterial disease.. Vascular 2024;32(4):797–803.
    doi: 10.1177/17085381241251772pubmed: 38705727google scholar: lookup
  38. Parsaeian M., Khodaie E., Izanloo B., Salehi K., NaghiZadeh S.. Determining the cut-off score of criterion-referenced tests using non-parametric estimation methods of the Youden index.. Educ. Meas. 2024;14(56).
  39. Patel A.A., Ginhoux F., Yona S.. Monocytes, macrophages, dendritic cells and neutrophils: an update on lifespan kinetics in health and disease.. Immunology 2021;163(3):250–261.
    pmc: PMC8207393pubmed: 33555612
  40. Reis I.L., Lopes B., Sousa P., Sousa A.C., Caseiro A.R., Mendonça C.M., Santos J.M., Atayde L.M., Alvites R.D., Maurício A.C.. Equine musculoskeletal pathologies: clinical approaches and therapeutical perspectives—a review.. Vet. Sci. 2024;11(5):190.
    pmc: PMC11126110pubmed: 38787162
  41. Ren B., Chen X., Lei P., Hou L., Wang H., Zhou Y., Ren L., Fan H., Wang Z., Yuan J.. The relationship between preoperative systemic immune inflammation index and prognostic nutritional index and the prognosis of patients with alveolar hydatid disease.. Front. Immunol. 2021;12.
    pmc: PMC8264590pubmed: 34248983
  42. Russell C.D., Parajuli A., Gale H.J., Bulteel N.S., Schuetz P., de Jager C.P., Loonen A.J., Merekoulias G.I., Baillie J.K.. The utility of peripheral blood leucocyte ratios as biomarkers in infectious diseases: a systematic review and meta-analysis.. J. Inf. Secur. 2019;78(5):339–348.
    pmc: PMC7173077pubmed: 30802469
  43. Samawi H.M., Yin J., Rochani H., Panchal V.. Notes on the overlap measure as an alternative to the Youden index: how are they related?. Stat. Med. 2017;36(26):4230–4240.
    pubmed: 28809042
  44. Saylik F., Akbulut T.. Systemic immune-inflammation index predicts major cardiovascular adverse events in patients with ST-segment elevated myocardial infarction.. Arq. Bras. Cardiol. 2022;119:14–22.
    pmc: PMC9352114pubmed: 35830117
  45. Scare J.A., Steuer A.E., Gravatte H.S., Kálmán C.S., Ramires L., de Castro L.D., Norris J.K., Miller F., Camargo F., Lawyer A., De Pedro P.. Management practices associated with strongylid parasite prevalence on horse farms in rural counties of Kentucky.. Vet. Parasitol. Reg. Stud. Rep. 2018;14:25–31.
    pubmed: 31014733
  46. Schafer A.I., Levine M.N., Konkle B.A., Kearon C.. Thrombotic disorders: diagnosis and treatment.. ASH Education Program Book 2003;2003(1):520–539.
    pubmed: 14633797
  47. Schattner A., Kadi J., Dubin I.. Reactive thrombocytosis in acute infectious diseases: prevalence, characteristics and timing.. Eur. J. Intern. Med. 2019;63:42–45.
    pubmed: 30795883
  48. Schlesinger M.. Role of platelets and platelet receptors in cancer metastasis.. J. Hematol. Oncol. 2018;11(1):125.
    pmc: PMC6180572pubmed: 30305116
  49. Šimundić A.M.. Measures of diagnostic accuracy: basic definitions.. ejifcc 2009;19(4):203.
    pmc: PMC4975285pubmed: 27683318
  50. Soulsby E.J.L.. Helminths, Arthropods and protozoa of Domesticated Animals.. .
  51. Taylor M.A., Coop R.L., Wall R.. Veterinary Parasitology.. .
  52. Tombak K.J., Rubenstein D.I.. How equids cope with macroparasites. Springer International Publishing; Cham: 2023. pp. 299–322.
  53. Tomita M., Ayabe T., Maeda R., Nakamura K.. Systemic immune-inflammation index predicts survival of patients after curative resection for non-small cell lung cancer.. In Vivo 2018;32(3):663–667.
    pmc: PMC6000798pubmed: 29695576
  54. Verocai G.G., Chaudhry U.N., Lejeune M.. Diagnostic methods for detecting internal parasites of livestock.. Vet. Clin. Food Anim. Pract. 2020;36(1):125–143.
    pubmed: 32029179
  55. Vinther A.M.L., Heegaard P.M., Skovgaard K., Buhl R., Andreassen S.M., Andersen P.H.. Characterization and differentiation of equine experimental local and early systemic inflammation by expression responses of inflammation-related genes in peripheral blood leukocytes.. BMC Vet. Res. 2016;12:1–13.
    pmc: PMC4888743pubmed: 27250718
  56. Vysniauskas A., Kaziunaite V., Kaminskaite I., Petkevicius S., Pereckiene A., Craven B.J.. The role of extense efficacy in the evaluation of anthelmintic resistance in horse strongyles.. Helminthologia 2004;41(2):73–80.
  57. Xie R., Xiao M., Li L., Ma N., Liu M., Huang X., Liu Q., Zhang Y.. Association between SII and hepatic steatosis and liver fibrosis: a population-based study.. Front. Immunol. 2022;13.
    pmc: PMC9520084pubmed: 36189280
  58. Ye Z., Hu T., Wang J., Xiao R., Liao X., Liu M., Sun Z.. Systemic immune- inflammatory index as a potential biomarker of cardiovascular diseases: a systematic review and meta-analysis.. Front. Cardiovasc. Med. 2022;9.
    pmc: PMC9393310pubmed: 36003917
  59. Yehia S.A., Badr A.M., Bashtar A.R., Ibrahim M.A.A., Mousa M.R., Mostafa N.A.. Immune response, oxidative stress, and histological changes of Wistar rats after being administered with Parascaris equorum antigen.. Sci. Rep. 2024;14(1):18069.
    pmc: PMC11300452pubmed: 39103392

Citations

This article has been cited 0 times.