An emergency department physician is evaluating a primigravida at 34 weeks gestation who p… — USMLE Step 2 CK

An emergency department physician is evaluating a primigravida at $34$ weeks gestation who presents with a $2$ -day history of gingival bleeding while brushing her teeth and a new rash on her legs. The $31$ -year-old patient reports feeling otherwise well and has had uncomplicated prenatal care until now. She denies headache, visual changes, right upper quadrant pain, or uterine contractions. Fetal movement is active.

Vital signs are:
* Temperature: $37.1^\circ\text{C}$ ( $98.8^\circ\text{F}$ )
* Blood pressure: $118/76$ mmHg
* Heart rate: $88/\text{min}$
* Respiratory rate: $16/\text{min}$

Physical examination reveals a gravid, non-tender uterus and scattered petechiae over both lower extremities. Fetal heart rate monitoring is reassuring.

Laboratory results are as follows:

Test	Result	Reference Range
Hemoglobin	11.2 g/dL	12.0 - 16.0 g/dL
Platelets	22,000/mm³	150,000 - 400,000/mm³
Leukocytes	8,400/mm³	4,500 - 11,000/mm³
Prothrombin time (PT)	12 sec	11 - 15 sec
Partial thromboplastin time (PTT)	28 sec	25 - 40 sec
Aspartate aminotransferase (AST)	22 U/L	8 - 40 U/L
Alanine aminotransferase (ALT)	18 U/L	7 - 35 U/L
Creatinine	0.7 mg/dL	0.6 - 1.2 mg/dL

Peripheral blood smear demonstrates profoundly reduced platelet numbers with a few large platelets. No schistocytes or immature leukocytes are observed.

Which of the following is the most appropriate next step in management?

A
Reassurance and repeat complete blood count in $2$ weeks
B
Prophylactic platelet transfusion
Administration of systemic glucocorticoidsCevap
D
Initiation of plasma exchange
E
Urgent induction of labor

Cevap

Administration of systemic glucocorticoids

Administration of systemic glucocorticoids is correct because this patient's clinical presentation of isolated, severe thrombocytopenia (platelets

< 30,000/\text{mm}^3

) accompanied by mucocutaneous bleeding in the absence of other systemic findings is diagnostic for Immune Thrombocytopenia (ITP). In pregnancy, first-line medical therapy for ITP requiring intervention is systemic glucocorticoids or intravenous immunoglobulin (IVIG). These therapies reduce the autoantibody-mediated destruction of platelets by the reticuloendothelial system, effectively raising the platelet count and decreasing the risk of severe hemorrhage.

Adım Adım Çözüm

Analyze the patient's presenting symptoms and vital signs.

The patient is a pregnant woman with new-onset mucocutaneous bleeding (petechiae, gingival bleeding) who is normotensive and lacks systemic signs of severe preeclampsia.

To rule out hypertensive disorders of pregnancy, which are a leading cause of maternal thrombocytopenia.

Evaluate the complete blood count, peripheral smear, and metabolic panel.

Isolated, severe thrombocytopenia (

22,000/\text{mm}^3

) with large platelets. Normal liver enzymes, normal creatinine, and absence of schistocytes.

To distinguish between Gestational Thrombocytopenia, Immune Thrombocytopenia (ITP), HELLP syndrome, and Thrombotic Thrombocytopenic Purpura (TTP).

Synthesize data to confirm the diagnosis.

The severe drop in platelets below

70,000/\text{mm}^3

and presence of symptoms exclude gestational thrombocytopenia. The lack of hemolysis and normal organ function exclude HELLP and TTP. The diagnosis is Immune Thrombocytopenia (ITP).

ITP is a diagnosis of exclusion characterized by autoantibody-mediated platelet destruction.

Determine the treatment threshold and select the appropriate therapy.

Because the platelet count is

< 30,000/\text{mm}^3

and the patient is actively bleeding, first-line medical therapy with systemic glucocorticoids (or IVIG) is indicated.

To raise the platelet count to a safe level, halt mucosal bleeding, and prepare for eventual safe delivery.

Anahtar Kavram

Differentiating causes of thrombocytopenia in pregnancy (Gestational vs ITP vs HELLP vs TTP) and recognizing that symptomatic ITP or platelets < 30,000/mm³ requires treatment with systemic glucocorticoids or IVIG.

Tahmini Süre:1m 30s

Soru

Cevap

Adım Adım Çözüm

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