CHAPTER Approach To Leucocytosis

58 Madhuchanda Kar, S Kartthik, Prantar Chakrabarti

ABSTRACT newer generation of analyzers can examine means elevation of WBC count for the thousands of leukocytes using flow cytometry–based patient’s age. Leukocytosis might be because of lymphoid methodology, some in combination with cytochemistry or myeloid series of cells. There is usually wide spectrum or fluorescence or conductivity, so they could elucidate of causes starting from benign diseases including different types of WBCs, including , and chronic or it might indicate , , , and . an underlying malignancy. So the approach in diagnosis Spurious elevations of the WBC count can also be seen, should be very systematic starting from meticulous including platelet clumps, nucleated RBCs, incomplete peripheral smear examination and then proceed to lysis of RBCs, cryoglobulins, and cryofibrinogen. further tests for clinching the diagnosis. So we therefore Hyperleukocytosis refers to a WBC count greater than discuss the approach to various types of leukocytosis in 100,000/mL, and is seen almost exclusively in this article. and myeloproliferative disorders. , or sludging of WBC in small vessels of the brain, lungs, and kidneys, INTRODUCTION is an oncologic emergency that may cause life-threatening Leukocytosis is defined as an elevation of9 the WBC cerebral infarcts, cerebral hemorrhage, or pulmonary count for the patient’s age. WBC count of 30 X 10 /L is insufficiency caused by impaired flow. Leukostasis considered elevated in an adult, but this value is normal is more common in acute myelogenous than in in the early neonatal period, so an appropriate reference acute lymphoblastic leukemia, because are value is critical. So reference intervals for WBC counts larger and more adhesive than lymphoblasts; it is rarely and relative percentages and absolute cell counts vary seen in chronic leukemias, even with extremely high WBC by patient age and hospital population. Leukocytosis is counts (Table 1) a common finding with a broad differential diagnosis, encompassing both benign and malignant entities. The WHAT MIGHT BE THE CAUSES OF LEUKOCYTOSIS? Leucocytosis

Table 1: Causes of Leucocytosis Blasts Primary hematologic etiology : Blasts Hereditary neutrophilia Blasts can be morphological identified by its Chronic idiopathic neutrophilia atypical morphology, but its not always reliable to distinguish between myeloid and lymphoid blasts. Myeloproliferative disorders (eg, CML, PV,ET) There are some blast equivalents described by WHO Familial myeloproliferative disease for hematololymphoid malignancies 2008 which Congenital anomalies and includes promonocytes, megakaryoblasts and atypical . The further characterization of the blast is done using immunophenotyping by flow cytometry or Leukocyte adhesion factor deficiency immunohistochemistry. Blast count more than or equal Familial cold urticaria and leukocytosis to 20 % is defined as acute leukemia. There are lower 2. Secondary to other disease entities: than 20% circulating blast count seen in chronic myeloid neoplasms, including myelodysplastic syndromes (MDS), myeloproliferative neoplasms (MPN), and overlap MDS/ Chronic Inflammation MPN. Iatrogenic or endogenous excess Cigarette smoking and Stress colony-stimulating factor (G-CSF) stimulation can cause Drug induced (Corticosteroids, beta agonists, lithium, a left shift of the myeloid lineage to the blast stage. Bone G-CSF etc) marrow infiltration by fibrosis, malignancy, or infection can be associated with circulating immature cells Heat Stroke (leukoerythroblastosis), including blasts and nucleated Marrow stimulation and Post splenectomy status red blood cells. 3. Spurious Myeloid Leukocytosis Platelet clumping Myeloid leukocytosis may represent (ie, Mixed cryoglobulinemia neutrophilia, eosinophilia, and basophilia) or monocytosis HAEMATOLOGY 320 days and may be caused by either benign or malignant benign either caused by days andmaybe last hoursto . Leukemoidreactionstypically maturation, thatis,frommyeloblasts tomature the in peripheral bloodallrecognizablestagesofneutrophil include may and 100,000/mL) 50,000– (typically leukocytosis Leukemoid reactionsrepresentexaggerated Neutrophilia is defined as an elevated circulating an elevated as count(>7.7X10 defined is Neutrophilia Neutrophilia (Figure 1) Neutrophilia Granulomatous Tumor/ disease Fig. ofNuetrophilia 1:Causes , culture Morphology, examination 9 /L inadults). Yes Ph orBCR ABL positive Toxic granulationandvacuoles Features supportingneoplastic Features supportingreactive Basophilia orEosinophilia Predominantly mature Pronounced leftshift WBC <50x10/L Thrombocytosis WBC >50x10/L DÖhle bodies Dacrocytes Dysplasia CML Fig. 2:Approach to Neutrophilia Leukoerthroblastic Peripheral smear Repeat counts examination Neutrophilia to behigh)andalsoincludesnucleatedRBCs. myelophthisisthe totalWBCdoesnotneed issimilar(but conditions. reactioncausedby A leukoerythroblastic with neutrophilic leukocytosis (ANC – 41 X 10 Peripheral smearexaminationshowsRouleauxformation 3. LDH 2. 1. g/dl andS.Globulin-4g/dl.Howtoproceed?(Figure2) and enzymes, but Total protein – 7.2 g/dl, S. Albumin – 3.2 bilirubin normal showed function Liver mg/dl, 2.6 – S.Cr and mg/dl 64 – S.Urea showed evaluation Biochemistry occasional nRBCs with and . count – 62 leukocyte X 10 total g/dl, 7 – Hb Peripheral showed examination mildpallor. blood from apart findings significant pallor forlast6months, on examinationshe had noother and pain low back old femalepresentedwith A 65yr ofNeutrophiliaCauses JAK 2/CaIRmutation (Non CMLMPN) Stool foroccultblood Digital rectalexamination Normalised 9 Reactive causesmore No cells/L and platelet count – 94 X 10 likely Investigation No Further 9 cells/L) and 9 cells/L, CHAPTER 58 321 /L 9 Observe No - FNo; Present? Present? No Yes - Clinical trial - Hydroxyurea; - Alemtazumab; cells/L) and platelet cells/L) - Corticosteroids; No - Cytotoxic agents; Symptoms AND/OR Marked eosinophilia 9 - Imatinib 400 mg/d; by cytogenetics or RT-PCR End-organ AND/OR damage Yes Other PDGFRA or PDGFRB rearrangements Positive? Finding of eosinophilia Finding of neoplasm - nilotinib; - dasatinib; - sorafenib; to 400 mg/d); - midostaurin or RT-PCR (for FIP1L1-PDGFRA fusion gene) or RT-PCR (for FIP1L1-PDGFRA Myeloproliferative Imatinib 100 mg/d - Escalate imatinib (up cells/L with prominent eosinophilia cells/L with prominent eosinophilia Peripheral blood screening with FISH (for CHIC2) blood screening with FISH (for Peripheral 9 cells/L. Biochemistry evaluation showed showed cells/L. Biochemistry evaluation 9 Yes Fig. 4: Approach to Eosinophilia to 4: Approach Fig. Rule out reactive eosinophilia Rule out reactive Lactate dehydrogenase S. Uric acid Stool for parasite Chest X ray and USG whole abdomen and pelvis Lymph node biopsy including histopathological examination by H&E and Immunohistochemistry thorax whole abdomen & pelvis and CECT CECT including neck Bone marrow aspiration and biopsy Molecular studies for PDGFR alpha and beta & FGFR1 mutation disorder? Underlying disease-specific Treat according to imatinib 400 mg/d MPN/MDS overlap ) entities guidelines AND/OR (AML, MDS, classic MPN, (B- or T-cell lymphoblastic disorders, 5M) or lymphoid Other WHO-defined myeloid (Absolute count – 13 X 10 count of 164 X 10 X 164 of count mildly elevated liver enzymes with normal bilirubin and enzymes with normal liver mildly elevated within normal limits. How to renal parameters were proceed? (Figure 4) 1. 2. 3. 4. 5. 6. 7. 8. 9. Echocardiography monocytes. A reactive monocytosis may be seen with be seen may monocytosis reactive A monocytes. or malignancy (ie, carcinoma, plasma cell myeloma, lymphoma), subacute bacterial endocarditis, chronic infections like , , Rocky mountain spotted fever, and kala-azar, autoimmune disorders, and splenectomy. Monocytosis An absolute monocytosis is defined as >1 X 10 examination mild pallor, scratch marks over the body marks over examination mild pallor, scratch inguinal and axillary enlarged bilateral cervical, and lymphnodes with maximum size of 3X3 cms . There was . Peripheral mild hepatomegaly and mild blood examination revealed Hb – 9g/dl, Total leucocyte count of 45 X 10 ). 3 Persistent neoplastic Transient other lineages ), moderate (AEC 3 Features supporting allergy or infection Immature cells present Cytopenias and dysplasia in Clinical presence of drugs, Features supporting reactive • Parasitic (helminths, ectoparasites, isospora, sarcocystis) ectoparasites, (helminths, • Parasitic HTLV) (HIV, • Viral (coccidiomycosis) • Fungal (tuberculosis) • Bacterial Fig. 3: Cases of Eosinophilia Fig. ), and severe (AEC >5000/mm ), and severe 3 and is followed by a decrease to adult levels levels by a decrease to adult and is followed

. The severity been arbitrarily of eosinophilia has . The severity 3 Eosinophilia Urine R/E and microscopic examination and microscopic Urine R/E electrophoresis Serum protein and pelvis USG whole abdomen S. PSA and CEA and colonoscopy Upper GI endoscopy S. Calcium and biopsy Bone marrow aspiration GENERAL APPROACH TO NEUTROPHILIA TO APPROACH GENERAL divided into mild (AEC 500–1500/mm Causes of Eosinophilia AD familial eosinophilia has been reported in several marked displayed in which individuals families eosinophilia, but had pulmonary, cardiac, or few to has been mapped disorder neurologic involvement.The 5q31-q33, a region that contains a cytokine chromosome cluster including genes encoding IL-3, IL-5, and GM-CSF. pruritus fever, with low-grade boy presented yr old 15 A On last 2 months. the neck for over multiple swelling and Eosinophilia (AEC) is 350 to The normal absolute eosinophil count 500/mm During the first few days of life cells/ 7000 to 13,000 ranges from neutrophil count normal the upper limit of the and at term gestation, for neonates born prematurely μL respectively, weeks of life. within the first few Autosomal Congenital primary neutrophilia is rare. 12 patients in three dominant neutrophilia kindred of the CSF3R mutation in activating an generations had of the G-CSF activation gene leading to constitutive receptor and increased proliferation and differentiation progressed the patients One of neutrophil precursors. of to MDS. functional disorders Marked neutrophilia is a hallmark of or by impaired adhesion of neutrophils that are caused motility, such as in patients with leukocyte adhesion deficiencies or actin dysfunction. Neutrophilia in Childhood in Neutrophilia 4. 5. 6. 7. 8. 9. 10. 1500–5000/mm HAEMATOLOGY 322 Basophilia, defined as > 0.3 X 10 Basophilia (Figure 6) neoplasms, unclassifiable. CML, and myelodys- plastic/myeloproliferative myelomonocytic leukemia,atypical(BCR-ABL negative) acute monoblastic/, CML, juvenile diagnosis, differential including chronic myelomonocytic leukemia(CMML), a raises monocytosis persistent cytometric flow with BM immunophenotyping and cytogenetic studies, because the of examination prompt The persistenceofanabsolutemonocytosisshould disorders, iron deficiency, chronic inflammation, and inflammation, rarely infection,includinginfluenzaandchickenpox. chronic deficiency, iron disorders, Reactive basophilia has been linked to hypersensitivity uncommon. is extremely rare. Isolatedbasophilia Fig. 5:Differentiating features of Reactive Vs Neoplastic Lymphocytosis Basophilia Monocytosis Small roundnuclei C.I.I. monoclonalB cell lymphocytosis Fig. 7:Lymphocytosis Fig. 6:Basophilia Monocytosis Folded orcleaved Follicular/mantin cell/lymphoma atypical; C.I.I. nuclei 9 /L inadults,isextremely Usually Pleomorphic Features supportingreactive Features supporting Features supporting Features supporting Clinical presenceofdrugs, Features supporting Predominantly mature Features supporting monomorphic allergy orinfection abnormalities Reactive changes Other lineage neoplastic Very rare neoplastic reactive Usually reactive neoplastic Transient Transient Adult tcellleukemia Convoluted nuclei Sezary syndrome Fig. 8:Lymphocytosis Lymphocytosis Neoplastic morphology canbeasfollows:(Figure8) Neoplastic lymphocytosis based on peripheral blood 6. 5. 4. 3. LDH 2. 1. How toproceed? reports were unremarkable. of 123X10 nuclei andplentyofsmudge cells and plateletcount small round are 90%smallmaturelymphocyteswith examination showed Hb – 8g/dl, TLC – 124 X 10 and moderatehepatosplenomegaly.Peripheral smear On examinationhehadgeneralisedlymphadenopathy including neck,axillaandinguinalregionforlast2yrs. swellingsold malepresentedwith A 80yr alloverbody the secondary tomalignancy(lymphoma,leukemia). vaccination, smoking,stress,endocrinedisorders and Drug hypersensitivity,autoimmunedisease,cytokines, bacterial infections, toxoplasma, , Babesiosis, Reactive lymphocytosis-Viral infections,some ofLymphocytosis Causes In adults, an absolute lymphocytecount of > 3.5 X 10 Lymphocytosis In conclusion, leukocytosis in a patient should prompt In conclusion,leukocytosisinapatient To summarize leukemia. chromosomal abnormalities, orjuvenile myelomonocytic myeloid leukemias, usually in association with 6p or 12p or bonemarrowbasophiliamayalso accompany acute occur in MDS and sideroblastic . Peripheral blood (>20%). Increased numbers ofmarrow basophils may to distinguishchronic phase fromaccelerated important very is eosinophilia of quantification CML, In leukemia andpolycythemiavera canhave basophilia. Myeloproliferative neoplasmslikechronicmyeloid used. adults, sotheappropriatereferenceintervals mustbe counts arehigherinchildrenandinfantscompared with can beconsidered lymphocytosis. Absolute Villous cytoplasm Hairy cellleukemia Splenic marginal zone lymphoma and itsvariant/ Immunophenotyping fromperipheralblood Chest XrayandUSGwholeabdomenpelvis S. Uricacid Direct CoombsTest Reticulocyte count 9 /L. Nocomorbiditiesandhisbiochemistry Lymphoplasmacytic Plasmacytoid lymphoma Burkitt/DLHCL Large cells 9 /L, There 9 /L CHAPTER 58 323 Hematol Oncol Clin N Am 2012; 26:303–19. Hematol Oncol Clin N 2012; 475-84. Immunol Allergy Immunol Clin N Am 2015; 35:439–52. /L, a pronounced left /L, a pronounced blasts and increased shift, 9 Chabot-Richards. D. S, George. T. I. Leukocytosis. Int Jnl S, George. T. Chabot-Richards. D. Lab Hem 2014; 36:279–88. I. Malignant or Benign Leukocytosis. ASH George. T. Education Book my patient have A.G. Why does Cerny J, Rosmarin Leukocytosis? Falchi L, Verstovsek disorders. S. Eosinophilia in hematological REFERENCES confirmation ofto be performed should smear of the blood Examination the automated the confirm to or differential manual a establish from myeloid of CBC distinction the allow will This differential. and WBC differential. leukemoid myeloid Distinguishing disorders. lymphoid reactions from myeloid malignancies is count >50 basophilia, WBC such as dysplasia, features difficult, with X 10 1. 2. 3. 4. favoring a myeloid malignancy with recommended BM malignancy with recommended favoring a myeloid ancillary testing. examination and appropriate

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Monomorphic rule out lymphoproliferative disorders

Pleomorphic reactive

Rule out out Rule MPN

Rule out out reactiveRule then and causes withproceed evaluation of hematolymphoid malignancy on Lymphoid Basophilia

Eosinophilia

Myeloid Leukocytosis Favouring Favouring malignancy then BMA and ancillary test Neutrophilia

Monocytosis Peripheral smear examinati

Blast Fig. 9: Approach in a Case of Leukocytosis 9: Approach Fig.

disorders Reactive causes including infection, malignancy, splenectomy and autoimmune

APPROACH IN A CASE OF LEUKOCYTOSIS: A CASE IN APPROACH OF and molecular studies BM examination with Flow cytometry, cytogenetics