Immune Thrombocytopenia and Pregnancy Differential Diagnoses

Updated: Sep 21, 2020
  • Author: Shamudheen Rafiyath, MD; Chief Editor: Srikanth Nagalla, MD, MS, FACP  more...
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DDx

Diagnostic Considerations

Thrombocytopenia is extremely common in mothers and newborns, affecting 7-8% of all women during pregnancy [12] and 15-20% of newborns admitted to neonatal intensive care units (NICUs). [21] Particular attention must be paid to the peripheral smear to rule out macrothrombocytopenia, which may occasionally occur in the absence of other disorders associated with the MYH9 gene (deafness, cataracts, and nephritis). [22] Immune thrombocytopenias are relatively rare causes of thrombocytopenia, but they always must be considered in the differential diagnosis because neonatal outcomes can be impaired significantly, and subsequent pregnancies can be affected.

Immune thrombocytopenia (ITP)

Other problems to consider in the differential diagnosis of ITP include the following:

  • Gestational thrombocytopenia
  • Preeclampsia
  • Systemic lupus erythematosus
  • Hemolytic-uremic syndrome
  • Thrombotic microangiopathy (TMA)
  • Antiphospholipid syndrome
  • Disseminated intravascular coagulation (DIC)
  • Hereditary thrombocytopenias (eg, May Hegglin anomaly, von Willebrand disease)
  • Thrombocytopenia secondary to drug exposure (eg, heparin, sulfonamides)
  • Other miscellaneous medical conditions that can cause thrombocytopenia (eg, leukemia, viral infection)
  • Acute fatty liver of pregnancy
  • Deficiency of vitamin B12, copper, and rarely folate.

Gestational thrombocytopenia occurs in the last half of pregnancy and accounts for three quarters of all cases of thrombocytopenia in pregnancy. A platelet count of less than 50,000/µL makes this diagnosis very unlikely. These women typically do not have a history of ITP, except during previous pregnancies, which usually resolves 4-8 weeks after delivery. The neonates of these women are not thrombocytopenic. [23]

Neonatal alloimmune thrombocytopenia (NAIT)

Other problems to consider in the differential diagnosis of NAIT include the following:

  • Sepsis
  • Congenital infections (eg, cytomegalovirus or HIV)
  • Stress (in premature newborns in the NICU)
  • Hypoxia secondary to perinatal asphyxia or aspiration
  • Congenital genetic syndrome
  • Congenital leukemia
  • Cyanotic congenital heart disease
  • Maternal preeclampsia (particularly if infant is growth restricted)
  • Maternal drug ingestion
  • Intracranial vascular abnormality

Differential Diagnoses