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Int J Hematol Oncol Stem Cell Res
Int J Hematol Oncol Stem Cell Res
IJHOSCR
International Journal of Hematology-Oncology and Stem Cell Research
2008-3009
2008-2207
Tehran University of Medical Sciences, Hematology-Oncology and Stem Cell Transplantation Research Center Tehran, Iran

10.18502/ijhoscr.v18i3.16105
IJHOSCR-18-249
Original Article
MDS-Type Morphologic Abnormalities of Peripheral Blood Granulocytes in Symptomatic COVID-19 Patients
Sharifi Mohammad Jafar 12
Gheibi Negar 3
Panahi Fatemeh 1
Sharifzadeh Sedigheh 12
Nasiri Nahid 12
1 Division of Laboratory Hematology and Blood Banking, Department of Medical Laboratory Sciences, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
2 Diagnostic Laboratory Sciences and Technology Research Center, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran
3 Department of Information Technology, Aliasghar Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
Corresponding Author: Nahid Nasiri, Division of Laboratory Hematology and Blood Banking, Department of Medical Laboratory Sciences, School of Paramedical Sciences, Shiraz University of Medical Sciences, Shiraz, Iran.E-mail: nahid.nasiri89@gmail.com
1 7 2024
18 3 249253
5 2 2024
12 5 2024
Copyright © 2024 Tehran University of Medical Sciences.
https://creativecommons.org/licenses/by-nc/4.0/ This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International license (https://creativecommons.org/licenses/by-nc/4.0/). Non-commercial uses of the work are permitted, provided the original work is properly cited.
Background: Hematological abnormalities in COVID-19 infection included quantitative and qualitative changes and should be further characterized. Evaluation for myelodysplastic syndromes (MDS) is usually prompted by abnormal hematologic findings and the presence of dysplastic morphologies. Viral infections are considered to be the cause of dysplastic morphologies and should be considered by morphologists. There are few reports of dysplastic abnormal morphologies in patients with COVID-19 infection. However, such correlations still have to be clarified.

Materials and Methods: In the present study, we examined the granulocyte lineage morphological abnormalities in symptomatic RT-PCR-confirmed COVID patients. Peripheral blood samples were collected from 82 patients with symptomatic COVID-19. Blood smears were prepared according to the standard Wright-Giemsa staining procedure. The morphological examination was carried out by two laboratory experts.

Results: Blood smear examination revealed common myelodysplastic syndrome (MDS) type abnormalities including but not limited to pseudo-pelger nuclear lobulation (4.8%), hypogranulation (7.3%), Howell-Jolly-like bodies or detached nuclear segments (6.0%) and elongated and thin nuclear filaments (6.0%). One case of abnormal immature granulocyte and ring form nucleus is also evident.

Conclusion: Our results accounted for the possibility of active COVID-19 infection in all subjects with granulocyte dysplasia. These results are of practical importance for patients suspected of having myelodysplastic syndromes or disease processes associated with myeloid malignancies.

Key Words

COVID-19
Myelodysplastic syndrome (MDS)
Granulocytes
Morphology
Peripheral blood
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pmcIntroduction

Since the onset of COVID-19 disease, several researchers have reported morphological abnormalities in peripheral blood cells1,2,3. Almost all blood cells showed an abnormality. As with other viral infections, attention was paid early on to atypical reactive lymphocytes as the most important morphological abnormality. However, myeloid cells also show striking changes, including dysplastic abnormalities4,6. An investigation for myelodysplastic syndrome (MDS) is usually prompted by abnormal hematologic findings. Blood smears show various cytopenias and dysplastic changes7,8. While the definitive diagnosis of MDS requires a bone marrow examination, a peripheral blood smear is mandatory. Identifying morphological abnormalities requires an appropriate staining procedure, a fresh blood smear, and a suitably skilled and experienced pathologist. Morphologists should consider the reactive cause of dysplasia, which may include drugs, viral infections, inflammatory diseases, and nonmalignant hematologic disorders8. Although the impact of COVID-19 on diagnostic hematology is well documented and reviewed9,10, new factors to consider have emerged and laboratory professionals should remain informed. In the present study, we examined the peripheral blood morphology of symptomatic COVID-19 patients.

MATERIALS AND METHODS

We examined the blood smear morphology of a cohort of symptomatic and RT-PCR-confirmed COVID-19 patients (n=82). In addition, a complete blood count (CBC) was performed on all patients as a routine laboratory test. Informed consent was obtained from all participants and the institutional ethics committee approved the present study. Blood samples were collected from September 2021 to March 2022 at Aliasghar Hospital (Shiraz University of Medical Sciences, Shiraz, Iran). Peripheral blood smears were prepared using the Wright-Giemsa staining method. Morphological examinations were carried out by two experienced morphologists. Abnormal myeloid morphologies were scored as positive if they occurred with a frequency of 5% or more. This detection limit was not applied to the presence of abnormal immature granulocytes. Patients with a history of hematologic malignancy or morphologic findings suggestive of leukemia were excluded from the study (one case). Demographic data was collected from medical records. This is a descriptive study and each abnormal morphology is reported by its relative frequency.

Results

In this study, common MDS-type abnormal morphologies caught our attention; These abnormalities included cytoplasmic hypogranulation, pseudo-pelger huet anomaly, abnormal chromate clumping, Howell-Jolly-like bodies, detached nuclear segments, hypersegmented neutrophils, nuclear border irregularities, abnormal nuclear filaments, ring-shape nucleus, and abnormal immature granulocytes. Hypersegmented neutrophils and nuclear border irregularities were the most common abnormal morphologies found in the present study (9.7%). Since these anomalies were observed together in most cases, we assigned them to the same group (Figure 1-F). Cytoplasmic hypogranularity was found in 7.3% of cases. Morphologies with a two-thirds or more reduction in neutrophil granule content were considered hypogranular11. While some neutrophils presented an almost entirely agranular cytoplasm (Figure 1-C), hypogranulation was sometimes associated with other abnormal morphologies. Abnormal chromatin clumping, identified by large blocks of chromatin separated by clear zones, was noted in 7.3% of patients (Figure 1-D). The incidence of detached nuclear lobes and Howell-Jolly-like bodies was 6% (Figure 1-A). Abnormal and elongated nuclear fragments between segments were noted in 6% of patients (Figure 1-H). Two-lobed neutrophils and a pseudo-pelger huet anomaly were present in 4.8% of blood smears. One patient presented with granulocyte progenitors with an abnormal distribution of cytoplasmic granules (Figure 1-E). A ring-shaped nucleus was determined in one peripheral blood smear (Figure 1-D). Patient demographics and frequency of MDS-type morphologic abnormalities are summarized in Table 1. Dysplastic morphological changes are shown in Figure 1.

Figure 1 Granulocyte morphological abnormalities in COVID-19; A, two nuclear lobes without connecting filaments, detached nuclear bodies at the periphery of the upper lobe are recognizable. B, scarce, unevenly distributed granules. C, typical pseudo-Pelger nuclear lobe with liquefied chromatin and almost entirely agranular cytoplasm. D, Nuclear appendages of varying sizes accompanied by abnormal chromatin clumping. E. unexpected presence of eosinophilic myelocyte with uneven granule distribution. F. Hypersegmented neutrophil with irregular lobes. G. The ring forms nuclei with malformed filaments between segments. H. Elongated thin nuclear filament.

Table 1 Demographic data

Age; ranges (median)	25-93 (51.2) Y	
Sex	F=31(38%)/M=51(62%)	
WBC; range (median)	2200-34700 (9464) /µl	
Hb; range (median)	7.1-19.9 (14.1) g/dl	
PLT; range (median)	12-691 (213) ×103/µl	
Frequency of morphologic abnormalities; n(%)	
Hypogranulation	6(7.3%)	
pseudo-pelger nuclear lobulation	4(4.8%)	
Abnormal chromatin clamping	6(7.3%)	
Abnormal immature granulocyte	1(1.2%)	
Howell-Jolly-like bodies & detached nuclear segments	5(6.0%)	
Hypersegmented neutrophil & nuclear border irregularity	8(9.7%)	
Elongated and thin nuclear filaments	5(6.0%)	
Ring form nucleus	1(1.2%)	

Discussion

Our study revealed dysplastic granulocytes in a group of symptomatic COVID-19 subjects. when examining a smear for morphological abnormalities, pathologists should be aware of artifacts and MDS-like reactive changes in blood and bone marrow smears8,12. Viral infections such as HIV are associated with marked dysplastic changes in the bone marrow4. In the present study, we detected both cytoplasmic and nuclear abnormalities in peripheral blood granulocytes. Detached nuclear lobes and Howell-Jolly-like bodies were noted in some patients (6%). A case report of Howell Jolly-like bodies in patients with COVID-19 has already been presented in the literature5. In addition to MDS, this abnormal morphology has also been reported to be found in other viral infections, including HIV114,15. Hypogranular neutrophils were common (7.3%). Consistent with our findings, Zini et al. also reported hypogranular and MPO-deficient neutrophils in a group of COVID-19 patients6. In our cohort, pseudo-pelger huet nucleus and agranular cytoplasm were found simultaneously in some patients. This is a characteristic neutrophil anomaly of the MDS type8,11,13. Case reports of pseudo-pelger huet anomaly in patients with COVID-19 have been documented by Akcabelen et al.3 and others17,18,19. Irregular nuclear projections were detected in our cohort. This type of change is more likely to affect MDS than reactive states12. We could find no reports of irregular nuclear ejection morphology in other studies. One patient presented with immature granulocytes (eosinophilic precursors) with uneven granule distribution. In the context of MDS, dysplastic immature granulocytes are more common in bone marrow smears; However, they may be detectable in blood smears from high-grade MDS16. Peripheral blood immature granulocytes were reported by other groups but with no evidence of dysplastic changes17,20. Another relatively common finding was hypersegmented neutrophils. This morphology is not specific to MDS and is usually found in megaloblastic anemia, uremia, and severe iron deficiency8, 11. Abnormal long and thin nuclear filaments were also identified (6%). Among them, few cells with myelokathexis-like thin interlobular strands were observed. The ring-shaped nucleus is a well-known neutrophilic dysplasia in MDS11. We also document this anomaly (one case). This type of abnormality was reported by Jain et.al in a group of 80 patients with COVID-1919.

Dysplasia and morphologic abnormalities in MDS contribute to a specific form of cell death known as pyroptosis21. Interestingly, pyroptosis is thought to be one of the main mechanisms for cell death and leukopenia in COVID-1922. Both entities likely share a similar cellular mechanism for cell death and dysplasia. Further investigations are required to elucidate the exact pathophysiological mechanisms. From a diagnostic perspective, it should be kept in mind that dysplastic changes are also important for the classification and prediction of disease progression in other myeloid malignancies23.

In addition to the peripheral blood smear, morphological abnormalities related to COVID-19 should also be considered in the bone marrow examination. Since there are no specific diagnostic biomarkers for MDS and the diagnosis is mainly based on morphological findings and cytogenetics, the diagnostician should consider distinguishing between active COVID-19. Our study suffers from the small sample size, but based on these findings and other reports, myeloid cell abnormalities are not uncommon in COVID-19 patients10. When such results are reproduced by other investigations, reflex COVID-19 testing and a watchful waiting strategy can avoid unnecessary bone marrow testing. Further studies are needed to confirm our results.
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References

1 Nazarullah A Liang C Villarreal A Peripheral Blood Examination Findings in SARS-CoV-2 Infection Am J Clin Pathol 2020 154 3 319 29 32756872
2 Yarali N Akcabelen YM Unal Y Hematological parameters and peripheral blood morphologic abnormalities in children with COVID-19 Pediatr Blood Cancer 2021 68 2 e28596 32761973
3 Akcabelen YM Gurlek Gokcebay D Yarali N Dysplastic Changes of Peripheral Blood Cells in COVID-19 Infection Turk J Haematol 2021 38 1 72 3 32812414
4 Luke F Orso E Kirsten J Coronavirus disease 2019 induces multi-lineage, morphologic changes in peripheral blood cells EJHaem 2020 1 1 376 83 32838398
5 Alisjahbana B Huang I Oehadian A The detection of Howell-Jolly body-like inclusions in a case of coronavirus disease-2019 (COVID-19) Blood Res 2020 55 4 191 33139589
6 Zini G Bellesi S Ramundo F Morphological anomalies of circulating blood cells in COVID-19 Am J Hematol 2020 95 7 870 2 32279346
7 Arber DA Orazi A Hasserjian R The 2016 revision to the World Health Organization classification of myeloid neoplasms and acute leukemia Blood 2016 127 20 2391 405 27069254
8 Mufti GJ McLornan DP van de Loosdrecht AA Diagnostic algorithm for lower-risk myelodysplastic syndromes Leukemia 2018 32 8 1679 96 29946191
9 Wiggill TM Mayne ES Vaughan JL Overview of the Haematological Effects of COVID-19 Infection Adv Exp Med Biol. 2021 1321 163 72 33656722
10 Zini G d'Onofrio G Coronavirus disease 2019 (COVID-19): Focus on peripheral blood cell morphology Br J Haematol 2023 200 4 404 19 36203344
11 Goasguen JE Bennett JM Bain BJ Proposal for refining the definition of dysgranulopoiesis in acute myeloid leukemia and myelodysplastic syndromes Leuk Res 2014 38 4 447 53 24439566
12 Invernizzi R Quaglia F Porta MG Importance of classical morphology in the diagnosis of myelodysplastic syndrome Mediterr J Hematol Infect Dis 2015 7 1 e2015035 25960863
13 Shekhar R Srinivasan VK Pai S How I investigate dysgranulopoiesis Int J Lab Hematol 2021 43 4 538 46 34031992
14 Karcher DS Frost AR The bone marrow in human immunodeficiency virus (HIV)-related disease. Morphology and clinical correlation Am J Clin Pathol 1991 95 1 63 71 1702927
15 Evans RH Scadden DT Haematological aspects of HIV infection Baillieres Best Pract Res Clin Haematol 2000 13 2 215 30 10942622
16 Hasserjian RP Myelodysplastic Syndrome Updated Pathobiology 2019 86 1 7 13 30041243
17 Schapkaitz E De Jager T Levy B The characteristic peripheral blood morphological features of hospitalized patients infected with COVID-19 Int J Lab Hematol 2021 43 3 e130 e4 33270978
18 Berber I Cagasar O Sarici A Peripheral Blood Smear Findings of COVID-19 Patients Provide Information about the Severity of the Disease and the Duration of Hospital Stay Mediterr J Hematol Infect Dis 2021 13 1 e2021009 33489048
19 Jain S Meena R Kumar V Comparison of hematologic abnormalities between hospitalized coronavirus disease 2019 positive and negative patients with correlation to disease severity and outcome J Med Virol 2022 94 8 3757 67 35467029
20 Pezeshki A Vaezi A Nematollahi P Blood cell morphology and COVID-19 clinical course, severity, and outcome J Hematop 2021 14 3 221 8 34249171
21 Sallman DA Cluzeau T Basiorka AA Unraveling the Pathogenesis of MDS: The NLRP3 Inflammasome and Pyroptosis Drive the MDS Phenotype Front Oncol. 2016 6 151 27379212
22 Bittner ZA Schrader M George SE Pyroptosis and Its Role in SARS-CoV-2 Infection Cells 2022 11 10 1717 35626754
23 Khoury JD Solary E Abla O The 5th edition of the World Health Organization Classification of Haematolymphoid Tumours: Myeloid and Histiocytic/Dendritic Neoplasms Leukemia 2022 36 7 1703 19 35732831
