Anitschkow nuclear structure: a study of pediatric hearts.

Anitschkow nuclear structures are commonly found in hearts of children who have died of various disorders. The peculiar chromatin pattern, as shown by immunohistochemical methods, occurs in striated muscle cells, histiocytes, Schwann cells, nondescript mesenchymal cells of the heart, and, rarely, cells outside of the heart. They are most abundant in the atrioventricular valves and in valve rings of premature infants. The histogenesis and significance of these unique nuclei are unknown, but their association with hypoxia and their similarity to forms seen in cell division suggest that the presence of increased numbers of Anitschkow nuclear structures may be a response to cardiac injury.