[Micronodular sonographic pattern of the spleen: a frequent finding in children and adolescents]

In textbooks about abdominal sonography, the parenchyma of the spleen is described as homogeneous. However, using high-frequency probes, sonography of the spleen in children often reveals a micronodular pattern.

To investigate the prevalence of a micronodular pattern in the pediatric spleen and to evaluate possible correlations to clinical parameters.

In 106 non-selected children (54 males, 52 females, mean age 7 years 10 months), the spleen was examined with a 17 MHz probe. Simultaneously the size of the spleen was measured, and other parameters such as leukocyte and thrombocyte counts were recorded. The pattern of the spleen was estimated using a four-step scale. 0: homogeneous tissue without micronodular components, 1: faint micronodular pattern/barely perceptible, 2 and 3: micronodular pattern clearly visible of moderate (2) or strong intensity (3).

In 33 children a homogenous pattern was found (31.1 %) and in 48 children (45.3 %) a micronodular pattern of the spleen was clearly visible. A statistical correlation to spleen size or leukocyte or thrombocyte count or CRP could not be proven. 52 % of children with an enlarged spleen had a micronodular pattern, as well as 66.7 % of children with leukocytosis, 44.7 % of children with increased CRP, and 54.5 % of children with thrombocytosis. However, there was a strong statistical correlation to the age of the children with a maximum at the age of 1 to 5 years.

A micronodular pattern of the spleen is frequent in children, even without clinical signs of infection. It is important to be aware of this finding and not to confuse it with pathological changes.