Novel biochemical prognostic indicators in COVID-19: Can CRP/albumin, urea/albumin, and LDH/albumin ratios be used to predict mortality and length of hospitalization? Novel biochemical prognostic indicators for COVID-19

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Zeynep Ergenc
Hasan Ergenç
Songül Araç
Mustafa Usanmaz
Ersin Alkılınç
Gülsüm Kaya
Cengiz Karacaer
Ahmet Nalbant
Tezcan Kaya


Objective: As the coronavirus disease 2019 (COVID-19) pandemic continues, clinical and laboratory predictors of progression to serious and lethal types of the illness are urgently needed. We aimed to investigate how well hematologic, biochemical, and immunologic biomarkers could distinguish between patients with and without severe or fatal COVID-19.

Material and Methods: This retrospective study was performed in the internal medicine departments of two institutions. Data were collected from the hospital database, and the medical files of 280 adult COVID-19 were reviewed. The relationship between hematologic and biochemical parameters which  include C-reactive protein (CRP)/albumin, urea/albumin, and lactate dehydrogenase (LDH)/albumin ratios and length of hospitalization, disease severity, and survival were investigated.

Results: Our series consisted of 280 adult COVID-19 patients (147 women, 133 men) with an average age of 58.34 ± 18.64 (range: 19 to 93). Most patients (n=171, 61.1%) had mild-moderate disease, while severe disease was diagnosed in 109 cases (38.9%). A total of 36 patients died due to COVID-19 yielding a mortality rate of 12.9%. The average length of hospitalization was 8.98 ± 5.80 days (range: 1-55 days). We noted that (CRP)/albumin, urea/albumin, and lactate dehydrogenase (LDH)/albumin ratios were significantly associated with severity of disease, mortality, and length of hospitalization.

Conclusion: Several biomarkers have been established that could help with risk stratification models for predicting serious and fatal results of COVID-19 infection. We suggest that clinicians closely track CRP/albumin, urea/albumin, and LDH/albumin ratios in hospitalized patients with respiratory distress as indicators for possible critical illness progression.


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Ergenc, Z., Ergenç, H., Araç, S., Usanmaz, M., Alkılınç, E., Kaya, G., Karacaer, C., Nalbant, A., & Kaya, T. (2022). Novel biochemical prognostic indicators in COVID-19: Can CRP/albumin, urea/albumin, and LDH/albumin ratios be used to predict mortality and length of hospitalization? Novel biochemical prognostic indicators for COVID-19. Medical Science and Discovery, 9(6), 310–318.
Research Article
Received 2022-05-13
Accepted 2022-06-07
Published 2022-06-09


Henry BM, De Oliveira MH, Benoit S, Plebani M, Lippi G. Hematologic, biochemical and immune biomarker abnormalities associated with severe illness and mortality in coronavirus disease 2019 (COVID-19): a meta-analysis. Clinical Chemistry and Laboratory Medicine (CCLM). 2020 Jul 1;58(7):1021-8. DOI:

Lippi G, Plebani M, Henry BM. Thrombocytopenia is associated with severe coronavirus disease 2019 (COVID-19) infections: a meta-analysis. Clinica chimica acta. 2020 Jul 1;506:145-8. DOI:

Lippi G, Plebani M. Procalcitonin in patients with severe coronavirus disease 2019 (COVID-19): a meta-analysis. Clinica chimica acta; international journal of clinical chemistry. 2020 Jun;505:190.

Li Q, Cao Y, Chen L, Wu D, Yu J, Wang H, He W, Chen L, Dong F, Chen W, Chen W. Hematological features of persons with COVID-19. Leukemia. 2020 Aug;34(8):2163-72. DOI:

Guan WJ, Ni ZY, Hu Y, Liang WH, Ou CQ, He JX, Liu L, Shan H, Lei CL, Hui DS, Du B. China medical treatment expert group for Covid-19. Clinical characteristics of coronavirus disease. 2019;382(18):1708-20. DOI:

Zhou F, Yu T, Du R, Fan G, Liu Y, Liu Z, Xiang J, Wang Y, Song B, Gu X, Guan L. Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study. The lancet. 2020 Mar 28;395(10229):1054-62. DOI:

Bellan M, Patti G, Hayden E, Azzolina D, Pirisi M, Acquaviva A, Aimaretti G, Aluffi Valletti P, Angilletta R, Arioli R, Avanzi GC. Fatality rate and predictors of mortality in an Italian cohort of hospitalized COVID-19 patients. Scientific reports. 2020 Nov 26;10(1):1-0.

WHO. COVID-19 Clinical management. Living guidance. 25 January 2021. Accessed 5 May 2021. Available at

Yüce M, Filiztekin E, Özkaya KG. COVID-19 diagnosis—a review of current methods. Biosensors and Bioelectronics. 2021 Jan 15;172:112752. DOI:

Yavuz S, Ünal S. Antiviral treatment of COVID-19. Turkish journal of medical sciences. 2020 Apr 21;50(SI-1):611-9. DOI:

Pinto LC, Bertoluci MC. Type 2 diabetes as a major risk factor for COVID-19 severity: a meta-analysis. Archives of endocrinology and metabolism. 2020 Jun 12;64:199-200. DOI:

He Z, Zhao C, Dong Q, Zhuang H, Song S, Peng G, Dwyer DE. Effects of severe acute respiratory syndrome (SARS) coronavirus infection on peripheral blood lymphocytes and their subsets. International journal of infectious diseases. 2005 Nov 1;9(6):323-30. DOI:

Henry BM. COVID-19, ECMO, and lymphopenia: a word of caution. The Lancet Respiratory Medicine. 2020 Apr 1;8(4):e24. DOI:

Violi F, Cangemi R, Romiti GF, Ceccarelli G, Oliva A, Alessandri F, Pirro M, Pignatelli P, Lichtner M, Carraro A, Cipollone F. Is albumin predictor of mortality in COVID-19?. Antioxidants & redox signaling. 2020 Jun 22. DOI:

Zhang JJ, Lee KS, Ang LW, Leo YS, Young BE. Risk factors for severe disease and efficacy of treatment in patients infected with COVID-19: a systematic review, meta-analysis, and meta-regression analysis. Clinical Infectious Diseases. 2020 Oct 15;71(16):2199-206. DOI:

Chen W, Zheng KI, Liu S, Yan Z, Xu C, Qiao Z. Plasma CRP level is positively associated with the severity of COVID-19. Annals of clinical microbiology and antimicrobials. 2020 Dec;19(1):1-7. DOI:

Pan F, Yang L, Li Y, Liang B, Li L, Ye T, Li L, Liu D, Gui S, Hu Y, Zheng C. Factors associated with death outcome in patients with severe coronavirus disease-19 (COVID-19): a case-control study. International journal of medical sciences. 2020;17(9):1281. DOI:

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