What is the diagnosis and treatment for a patient with mild anemia and thrombocytopenia, with a CBC showing hemoglobin of 12.9 and a platelet count of 110?

Diagnosis and Management of Mild Anemia with Thrombocytopenia

This patient requires immediate evaluation for thrombotic microangiopathy (TMA) and immune thrombocytopenic purpura (ITP), with urgent laboratory workup including peripheral blood smear, LDH, haptoglobin, indirect bilirubin, and ADAMTS13 activity level to guide definitive treatment. 1, 2

Immediate Diagnostic Workup

When encountering combined anemia and thrombocytopenia, immediately order:

• Peripheral blood smear examination by a qualified hematologist to assess for schistocytes (>1% suggests TMA), platelet size abnormalities, and pseudothrombocytopenia from EDTA-dependent agglutination 1
• Hemolysis markers: LDH, haptoglobin, indirect bilirubin, and reticulocyte count 1
• ADAMTS13 activity level and inhibitor titer - this must be sent urgently as results guide immediate life-saving treatment 2
• Direct Coombs test to confirm non-immune hemolysis if microangiopathic process suspected 1
• Renal function: creatinine, urinalysis for hematuria/proteinuria 1

Differential Diagnosis Framework

If Schistocytes Present with Hemolysis Markers

The triad of non-immune hemolytic anemia, thrombocytopenia, and renal involvement defines TMA 1, 2:

• ADAMTS13 <10%: Thrombotic thrombocytopenic purpura (TTP) - immediately initiate therapeutic plasma exchange and methylprednisolone 1g IV daily for 3 days without waiting for confirmatory results 2
• Do NOT transfuse platelets in suspected TTP unless life-threatening bleeding occurs, as platelet transfusion may worsen thrombosis 2
• ADAMTS13 >10% with TMA features: Atypical hemolytic uremic syndrome (aHUS) - begin eculizumab therapy along with meningococcal vaccination and penicillin prophylaxis 2

If Isolated Thrombocytopenia (No Hemolysis)

Primary considerations include ITP, drug-induced thrombocytopenia, or pseudothrombocytopenia 1:

• Exclude medications: quinidine, heparin, sulfonamides, sulfonylureas, dipyridamole, salicylates, and alcohol 1
• HIV and HCV testing is mandatory in all adult patients regardless of risk factors, as thrombocytopenia may precede other symptoms by years 1
• Helicobacter pylori testing with urea breath test or stool antigen test should be considered in adults 1
• Bone marrow examination is indicated if age >60 years, systemic symptoms present, or splenectomy being considered 1

Treatment Based on Platelet Count Severity

Platelet Count 110,000/mm³ (This Patient)

This mild thrombocytopenia (>100,000/mm³) rarely requires immediate intervention unless active bleeding or planned invasive procedures 3:

• Monitor weekly CBC if ITP suspected 1
• No treatment required if asymptomatic and no bleeding manifestations 3
• Address underlying cause: If iron deficiency confirmed (low ferritin, increased RBC distribution width), initiate iron replacement as profound iron deficiency can cause thrombocytopenia 4, 5

Platelet Count 30,000-50,000/mm³

Purpura may manifest; check counts at least 3 times weekly 1, 3:

• For ITP: Moderate to high-dose glucocorticoids combined with immunosuppressive agent (azathioprine, mycophenolate mofetil, or cyclosporine) 1
• Initial therapy with IV methylprednisolone pulses (1-3 days) is encouraged 1
• IVIG may be considered in acute phase or inadequate glucocorticoid response 1

Platelet Count <30,000/mm³

Significant bleeding risk with minimal trauma 3:

• Platelet transfusions according to local guidelines if count continues falling below 30,000/mm³ 1
• For lupus-associated thrombocytopenia: First-line treatment consists of moderate/high-dose glucocorticoids combined with immunosuppressive agent 1
• Rituximab should be considered in patients with no response to glucocorticoids (failure to reach platelet count >50,000/mm³) or relapses 1

Platelet Count <10,000/mm³

Spontaneous bleeding risk - hematologic emergency requiring hospitalization 3:

• Immediate hematology consultation 1
• Aggressive immunosuppression for ITP with high-dose glucocorticoids and IVIG 1
• Thrombopoietin receptor agonists (romiplostim) may be considered for refractory cases, with median weekly dose 2-3 mcg/kg subcutaneously 6

Critical Pitfalls to Avoid

• Never assume isolated thrombocytopenia without examining peripheral smear - pseudothrombocytopenia occurs in 0.1% of adults and must be excluded 1
• Absence of schistocytes does not exclude TMA due to low test sensitivity; clinical suspicion with hemolysis markers takes precedence 1
• Splenomegaly argues strongly against primary ITP - less than 3% of ITP patients have palpable spleens, similar to healthy population 1
• Mild anemia (Hb 12.9 g/dL) with normal MCV (98 fL) suggests blood loss rather than hemolysis unless reticulocyte count elevated 1
• Do not delay ADAMTS13 testing when TMA suspected - this is the critical decision point between life-saving plasma exchange versus complement inhibition 2