Pearson’s syndrome without marrow involvement

A child with a mitochondrial DNA deletion who presented with pancreatic exocrine insuYciency is reported. Though she developed many other features of Pearson’s syndrome, there was no bone marrow involvement. Syndromes associated with mitochondrial DNA defects are highly variable and absence of one feature should not inhibit investigation. (Arch Dis Child 1997;77:56‐57)