Prenatal infantile cortical hyperostosis (Caffey's disease): a 'hepatic myeloid hyperplasia-pulmonary hypoplasia sequence' can explain the lethality of early onset cases.

BACKGROUND

Infantile cortical hyperostosis (ICH) is benign and self-limiting when it presents near or after birth but is usually lethal when it presents earlier.

METHODS

We present the clinical, ultrasonic, radiographic and pathologic findings in an instructive case of early onset prenatal ICH.

RESULTS

A 40-year-old G2P1 woman delivered spontaneously at 22 weeks' gestation. Prenatal ultrasounds showed rib and mandibular abnormalities as well as short humeri. Post-mortem radiographs showed asymmetric hyperostosis in long bones, mandible, scapulae and pelvis with sparing of spine, hands, feet and skull. The affected skeleton showed marked bony sclerosis and ballooning of the diaphyses of the long bones with periosteal sclerosis. A complete autopsy showed characteristic histologic findings in affected bones. Previous reports at 20+ weeks have described anasarca, fetal hydrops, hepatomegaly, and pulmonary hypoplasia. In our case, there was no hydrops/anasarca; hepatomegaly, due to massive extramedullary hematopoiesis with marked myeloid hyperplasia, combined with ribcage abnormalities, caused mild pulmonary hypoplasia.

CONCLUSION

We hypothesize that early onset fetal ICH is usually lethal because massive hepatic myeloid hyperplasia sequentially causes: (1) hepatomegaly and, in conjunction with rib abnormalities, mild pulmonary hypoplasia, (2) sinusoidal and pre-sinusoidal portal hypertension followed by ascites/hydrops, and (3) ascites/hydrops-induced severe pulmonary hypoplasia.