Chapter 480 Splenomegaly

Clinical Manifestations

A soft, thin spleen is palpable in 15% of neonates, 10% of normal children, and 5% of adolescents. In most individuals, the spleen must be 2-3 times its normal size before it is palpable. The spleen is best examined when standing on the right side of a supine patient by palpating across the abdomen as the patient inspires deeply. A splenic edge felt more than 2 cm below the left costal margin is abnormal. An enlarged spleen might descend into the pelvis; when splenomegaly is suspected, the abdominal examination should begin at a lower starting point. Superficial abdominal venous distention may be present when splenomegaly is a result of portal hypertension. Radiologic detection or confirmation of splenic enlargement is done with ultrasonography, CT, or technetium-99 sulfur colloid scan. The latter also assesses splenic function.

Differential Diagnosis

Specific causes of splenomegaly are listed in Table 480-1. A thorough history with a focus on systemic complaints (fever, night sweats, malaise, weight loss) in combination with a complete blood count and careful review of the peripheral smear can help guide diagnosis. Unique problems are discussed next.

Table 480-1 DIFFERENTIAL DIAGNOSIS OF SPLENOMEGALY BY PATHOPHYSIOLOGY

ANATOMIC LESIONS

Cysts, pseudocysts

Hamartomas

Polysplenia syndrome

Hemangiomas and lymphangiomas

Hematoma or rupture (traumatic)

HYPERPLASIA CAUSED BY HEMATOLOGIC DISORDERS

Acute and Chronic Hemolysis *

Hemoglobinopathies (sickle cell disease in infancy with or without sequestration crisis and sickle variants, thalassemia major, unstable hemoglobins)

Erythrocyte membrane disorders (hereditary spherocytosis, elliptocytosis, pyropoikilocytosis)

Erythrocyte enzyme deficiencies (severe G6PD deficiency, pyruvate kinase deficiency)