Chapter 443 Pearson’s Syndrome

Pearson’s syndrome is a form of congenital hypoplastic anemia that may be confused initially with Diamond-Blackfan syndrome or transient erythroblastopenia of childhood. It also involves the pancreas, kidney, and liver. The marrow failure usually appears in the neonatal period and is characterized by a macrocytic anemia and, occasionally, neutropenia and thrombocytopenia. The hemoglobin F level is elevated, and there are vacuolated erythroblasts and myeloblasts in the marrow. This very rare disorder is considered a unique variant of congenital sideroblastic anemia because the marrow also contains ringed sideroblasts. Associated clinical features include failure to thrive, pancreatic fibrosis with insulin-dependent diabetes and exocrine pancreatic deficiency, muscle and neurologic impairment, villous atrophy with chronic diarrhea, and often early death.

This multiorgan disorder is due to sporadic, mitochondrial DNA deletions. There is heterogeneity in different tissues and between patients, accounting for the variable clinical picture. The proportion of deleted mtDNA in the bone marrow correlates with the severity of the hematologic picture, and a change in the percentage of tissue mtDNA types over time may be associated with spontaneous improvement of red blood cell hypoproliferation. Therapy includes transfusions of red blood cells as needed. Granulocyte colony-stimulating factor can reverse episodes of severe neutropenia.