What bloodwork parameters should be monitored in a patient recovering from dengue?

Bloodwork Parameters to Monitor in Patients Recovering from Dengue

Complete blood count (CBC) with platelet count is the most critical laboratory parameter to monitor in patients recovering from dengue, with particular attention to platelet count recovery and normalization of leukocyte count. 1

Key Laboratory Parameters to Monitor

Primary Parameters (Most Critical)

• Platelet Count

  • Monitor until count exceeds 150,000/mm³ 1, 2
  • Thrombocytopenia (<150,000/mm³) is present in approximately 40% of dengue patients 2
  • Platelet recovery typically begins around day 5 of illness 3
  • Continue monitoring until sustained upward trend is established

• Complete Blood Count

  • White Blood Cell Count: Monitor until leukopenia (<4,000 cells/mm³) resolves 2
  • Hematocrit: Monitor for normalization from previous hemoconcentration 1
  • Mean Platelet Volume (MPV): Decreasing MPV correlates with platelet recovery 3

Secondary Parameters

• Liver Function Tests

  • AST/ALT: Monitor for normalization of previously elevated liver enzymes 1
  • Elevated liver enzymes are common in dengue and should return to normal during recovery

• Coagulation Profile (if abnormal during acute phase)

  • PT/INR: Particularly important if previously >2.0 (associated with bleeding risk) 4
  • aPTT: Should normalize from prolonged values (>60 seconds increases bleeding risk) 4

Monitoring Schedule and Thresholds

1. First Week After Acute Phase:

   • CBC with platelet count: Every 24-48 hours until platelets >100,000/mm³
   • Liver function tests: Every 48-72 hours if previously abnormal

2. Follow-up Period (After platelets >100,000/mm³):

   • CBC with platelet count: Once weekly until complete normalization
   • Liver function tests: Once weekly until normalized

3. Warning Thresholds requiring more intensive monitoring:

   • Platelets failing to show upward trend by day 7-10
   • Persistent leukopenia beyond 7 days
   • Persistent or worsening liver enzyme elevation

Special Considerations

• Patients with Comorbidities: More frequent monitoring may be needed, especially for those with underlying hematological disorders, liver disease, or on antiplatelet/anticoagulant medications 1

• Patients Who Had Severe Dengue: More comprehensive monitoring including:

  • Renal function tests (BUN, creatinine)
  • Electrolytes (particularly if significant fluid resuscitation was required)
  • Consider repeat ultrasonography if evidence of plasma leakage was present 5

• Pregnant Women: Require more intensive surveillance with more frequent CBC monitoring 1

Interpretation of Laboratory Findings

• Platelet Recovery Pattern: Typically begins around day 5 of illness with gradual improvement
• Leukocyte Recovery: Usually follows platelet recovery
• Persistent Thrombocytopenia (beyond 10 days): Consider alternative diagnoses or complications
• Persistent Abnormal Liver Enzymes: May indicate liver injury requiring further evaluation

Common Pitfalls to Avoid

• Premature Discontinuation of Monitoring: Platelets may appear to recover then drop again
• Overlooking Coagulation Abnormalities: Patients may have coagulation defects despite normal platelet counts 6
• Missing Secondary Infections: Persistent or recurrent fever with worsening leukocytosis may indicate secondary bacterial infection
• Failure to Consider Prior Antiplatelet Medication: Patients on prior antiplatelet drugs have increased bleeding risk and require closer monitoring 4

By systematically monitoring these parameters, clinicians can ensure complete recovery from dengue infection and promptly identify any complications that may arise during the recovery phase.