Hematologists are consulted for findings suggestive of a hematologic disease as well as for hematologic manifestations that occur secondary to other diseases*. These abnormal findings usually derive from clinical examination (eg, splenomegaly, signs of cutaneous hemorrhage, unilateral leg edema suggestive of a venous thrombosis) or, more commonly, laboratory tests (eg, blood counts, coagulation tests) indicative of a disease of blood cell regulation or of hemostasis or thrombosis. The consultant’s role is to confirm or determine the diagnosis and, often, to assume management and provide continuous patient care as required by the particular hematologic disease. The consultation should include a detailed medical history, physical examination, and personal review of all available laboratory test results to permit an initial assessment, development of a differential diagnosis, and a systematic approach to further testing if required.
This chapter discusses the general diagnostic approach to common findings that may lead to a hematology consultation, as listed in Chap. 1, Table 1–1. For a more detailed discussion of each, including epidemiology, pathogenesis, and treatment, refer to the corresponding chapters cited.
Acronyms and Abbreviations
aPTT, activated partial thromboplastin time; ADAMTS-13, a disintegrin and metalloprotease with a thrombospondin type 1 motif member 13; ALC, absolute lymphocyte count; ALL, acute lymphoblastic leukemia; AML, acute myelogenous leukemia; ANC, absolute neutrophil count; aPL, antiphospholipid antibodies; APS, antiphospholipid antibody syndrome; BCR-ABL, breakpoint cluster region-Abelson; CAPS, catastrophic antiphospholipid syndrome; CBC, complete blood count; CLL, chronic lymphocytic leukemia; CML, chronic myelogenous leukemia; CMML, chronic myelomonocytic leukemia; CNL, chronic neutrophilic leukemia; CRP, C-reactive protein; CTA, computerized tomographic angiography; DIC, disseminated intravascular coagulation; DOAC, direct oral anticoagulants; DVT, deep venous thrombosis; EDTA, ethylenediaminetetraacetic acid; EPO, erythropoietin; ESR, erythrocyte sedimentation rate; ET, essential thrombocythemia; FVL, factor V Leiden; HELLP, hemolysis, elevated liver enzymes, low platelet count; HLH, hemophagocytic lymphohistiocytosis; HHT, hereditary hemorrhagic telangiectasia; HIT, heparin-induced thrombocytopenia; HIV, human immunodeficiency virus; HUS, hemolytic uremic syndrome; IgG, immunoglobulin G; IgM, immunoglobulin M; INR, international normalized ratio; ITP, immune thrombocytopenia; JAK2, Janus kinase 2; LDH, lactate dehydrogenase; LGLL, large granular lymphocytic leukemia; MCV, mean corpuscular volume; MDS, myelodysplastic syndrome; MPN, myeloproliferative neoplasm; NK, natural killer; nRBC, nucleated red blood cells; NSAID, nonsteroidal antiinflammatory drugs; PCR, polymerase chain reaction; PE, pulmonary embolism; PFA, platelet function analysis; PGM, prothrombin gene mutation; PNH, paroxysmal nocturnal hemoglobinuria; PT, prothrombin time; PV, polycythemia vera; RBC, red blood cell; RIPA, ristocetin-induced platelet aggregation; RT, reptilase time; SD, standard deviation; SLE, systemic lupus erythematosus; SPEP, serum protein electrophoresis; TIBC, total iron binding capacity; TSAT, transferrin saturation; TT, thrombin time; TTP, thrombotic thrombocytopenic purpura; UPEP, urine protein electrophoresis; VTE, venous thromboembolism; VWD, von Willebrand disease; WBC, white blood cell; WHO, World Health Organization.
THE HEMATOLOGY CONSULTANT’S ROLE
The hematology consultant provides expertise in ...