From fossil to fetus: nonhemorrhagic germinal matrix echodensity caused by mineralizing vasculitis--hypothesis of fossilizing germinolysis and gliosis.
Subventricular echodensities medioventral to the caudate nucleus near the caudothalamic groove are regular ultrasonographic findings in preterm infants with germinal matrix hemorrhages. The transformation into pseudocysts is termed germinolysis. Interestingly, identical ultrasonographic findings are rarely even reported for near-term infants. We examined 5 cases of near-term infants presenting with various localized subventricular echodensities after various noncerebral infections (intra-amniotic infection, gastroenteritis of unidentified pathogens, septic wound, and a twin pair with rotavirus gastroenteritis), suggesting an inflammatory or ischemic rather than a hemorrhagic etiology. With high-resolution ultrasonography, these lesions showed similar characteristics: all were space-occupying, homogeneous, echodense, and ultimately transformed into pseudocysts. Additionally, Doppler ultrasonography showed linear perivascular echodensities in the basal ganglia of one infant. All infants were also examined by cerebral magnetic resonance imaging (MRI) including T2*-weighted gradient-echo sequences so that subventricular hemorrhages could be excluded in 4 infants. One of these 4 infants died unexpectedly at home. Brain autopsy revealed nonhemorrhagic germinal matrix pseudocysts with gliotic walls. Based on our findings and the original literature, we favored an ischemic infarction of the strongly vascularized and highly metabolic germinal matrix as cause of this germinolysis and gliosis. We postulated that the infarction was the result of an obstructive and possibly mineralizing, or even fossilizing vasculopathy due to an inflammatory response. The precise pathogenesis of the suspected immune-mediated vasculitis remains unknown. We concluded that cerebral ultrasonography should be performed in infants with noncerebral infection and that it should be complemented by MRI in cases of subventricular echodensities to prove or to exclude a germinal matrix hemorrhage.
van Baalen
Andreas
A
Department of Neuropediatrics, University Medical Center Schleswig-Holstein, Kiel, Germany. van.baalen@pedneuro.uni-kiel.de
Rohr
Axel
A
D002543:Cerebral Hemorrhage / Q000150:complications* / Q000000981:diagnostic imaging; D002675:Child, Preschool; D005260:Female; D005333:Fetus / Q000473:pathology*; D005911:Gliosis / Q000150:complications*; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D014463:Ultrasonography / Q000379:methods; D014657:Vasculitis / Q000150:complications*