What is the management approach for a patient with a Complete Blood Count (CBC) showing tear drop cells, stomatocytes, and giant platelets?

Management of CBC Findings with Tear Drop Cells, Stomatocytes, and Giant Platelets

Initial Diagnostic Approach

This constellation of findings—tear drop cells, stomatocytes, and giant platelets—requires immediate evaluation for myelodysplastic syndrome (MDS), inherited platelet disorders, and thrombotic microangiopathy. The presence of tear drop cells is particularly concerning for bone marrow pathology, while giant platelets suggest either inherited platelet disorders or MDS-related dysplasia 1.

Critical Laboratory Workup

• Complete peripheral blood smear review to quantify dysplastic features: assess for pseudo-Pelger-Huet cells, hypogranulation, anisocytosis, poikilocytosis, and confirm the presence of tear drop cells and giant platelets 1
• Complete blood count with differential including platelet count, hemoglobin, and white blood cell count to assess for cytopenias 1
• Reticulocyte count, LDH, haptoglobin, and indirect bilirubin to evaluate for hemolysis, particularly if schistocytes are present alongside tear drop cells 1, 2
• Direct antiglobulin test (DAT) to differentiate immune from non-immune hemolysis 1, 2

Distinguishing MDS from Other Causes

Bone marrow aspirate and biopsy with cytogenetics is mandatory if cytopenias are present or if dysplasia affects >10% of any cell lineage 1. The 2021 ESMO guidelines specify that tear drop cells are a recognized sign of dysplasia in MDS, and bone marrow evaluation is essential to assess cellularity, fibrosis, and exclude hypoplastic or fibrotic MDS 1.

• Perform bone marrow examination if:

  • Hemoglobin <11.0 g/dL, neutrophils <1500/μL, or platelets <100,000/μL for ≥4 months 1
  • Marked dysplasia (>10%) in any cell lineage 1
  • Unexplained persistent cytopenias 1

• Cytogenetic analysis and FISH panel for del(5q), del(7q), del(13), del(17), t(4;14), t(11;14), and t(14;16) 1

• Iron staining to evaluate for ring sideroblasts 1

Evaluating for Inherited Platelet Disorders

Giant platelets with thrombocytopenia suggest inherited disorders such as Bernard-Soulier syndrome, May-Hegglin anomaly, or MYH9-related diseases 3, 4, 5.

Specific Testing for Giant Platelet Syndromes

• Platelet function testing including aggregation studies with ADP, collagen, epinephrine, and ristocetin 5
• Flow cytometry for platelet glycoproteins (GPIb-IX-V complex for Bernard-Soulier syndrome, αIIbβ3 for Glanzmann thrombasthenia) 3
• Leukocyte examination for Döhle-like inclusion bodies characteristic of May-Hegglin anomaly 5
• Genetic testing for MYH9 mutations if MYH9-related disease is suspected 3

Key clinical distinction: May-Hegglin anomaly presents with thrombocytopenia (26-178 × 10⁹/L), giant platelets, and leukocyte inclusions, but bleeding severity does not correlate with platelet count 5. Previous therapies with corticosteroids, IVIG, or splenectomy are ineffective 5.

Assessing for Thrombotic Microangiopathy

If schistocytes accompany tear drop cells, immediately evaluate for TTP/HUS 1, 2.

• ADAMTS13 activity level and inhibitor titer 1, 2
• Prothrombin time, activated partial thromboplastin time, fibrinogen 1
• Complement testing (C3, C4, CH50) for complement-mediated HUS 1, 2
• Blood smear for schistocytes (>1% is significant) 2

Management Algorithm Based on Findings

If MDS is Confirmed

• Risk stratification using IPSS-R scoring system 1
• Supportive care with RBC transfusions when hemoglobin <7.0 g/dL in stable patients 1
• Prophylactic platelet transfusion when counts <10,000/μL without bleeding, or <20,000/μL with bleeding risk 1
• Consider erythropoiesis-stimulating agents for lower-risk MDS with anemia 1
• Hypomethylating agents (azacitidine or decitabine) for higher-risk disease 1

If Inherited Platelet Disorder is Confirmed

• Avoid unnecessary platelet transfusions except for active bleeding or before invasive procedures 3, 6
• Desmopressin (DDAVP) can be effective for mild bleeding in May-Hegglin anomaly and other qualitative platelet defects 5
• Recombinant factor VIIa for severe bleeding unresponsive to platelet transfusion 3
• Activity restrictions to avoid trauma when platelet count <50 × 10³/μL 6
• Genetic counseling for affected families 3

If TTP/HUS is Confirmed

• Grade 4 (life-threatening): Immediately initiate therapeutic plasma exchange, methylprednisolone 1g IV daily × 3 days, and consider rituximab 1, 2
• Grade 3 (laboratory findings with clinical consequences): Admit patient, prednisone 1-2 mg/kg/day, RBC transfusion to maintain hemoglobin 7-8 g/dL 1, 2
• Grade 2 (evidence of hemolysis without severe consequences): Prednisone 0.5-1 mg/kg/day, weekly hemoglobin monitoring 1, 2

Common Pitfalls to Avoid

• Do not assume immune thrombocytopenia (ITP) without excluding inherited platelet disorders when giant platelets are present 4, 5
• Do not delay bone marrow examination if cytopenias persist >4 months or dysplasia is evident 1
• Do not transfuse platelets prophylactically in inherited platelet disorders unless platelet count <10,000/μL or active bleeding 6
• Do not miss TTP/HUS by failing to examine for schistocytes when tear drop cells are present 1, 2
• Do not use corticosteroids, IVIG, or splenectomy for May-Hegglin anomaly—they are ineffective 5

Monitoring Recommendations

• Weekly CBC until diagnosis is established and treatment initiated 1
• Bone marrow surveillance every 6-12 months if MDS is diagnosed 1
• Bleeding assessment using standardized bleeding scores for inherited platelet disorders 7
• Hemoglobin monitoring weekly during steroid tapering if hemolytic anemia is present 1