HYPOSPLENIC BLOOD PICTURE IN SYSTEMIC AMYLOIDOSIS - ITS ABSENCE IS NOT A PREDICTABLE SIGN FOR ABSENCE OF SPLENIC INVOLVEMENT

We studied a total of 61 cases of systemic and senile amyloidosis to e valuate the significance of a ''hyposplenic blood picture'' (the prese nce of numerous Howell-Jolly bodies) in these patients and to correlat e its presence with the pattern and severity of the splenic involvemen t. To ascertain whether this peripheral blood picture is prevalent wit h a certain type of amyloidosis, we classified all cases by immunostai ning with a panel of antibodies against AL amyloid (kappa and lambda l ight chains), serum amyloid-associated protein, prealbumin, beta-2 mic roglobulin, and amyloid p component. Based on immunostaining results, all cases were classified as AL (31 cases), AA (8 cases), or senile (p realbumin-positive, 22 cases) amyloidosis. Howell-Jolly bodies were id entified in six patients with amyloid L amyloidosis; of these, four ca ses had diffuse splenic cord involvement, one had a follicular pattern , and one had a vascular pattern. Only one of these patients had a typ ical hyposplenic blood picture. This patient had far-advanced diffuse splenic involvement. The remaining five patients had rare to few Howel l-Jolly bodies. In addition, 12 other patients had diffuse splenic inv olvement with no Howell-Jolly bodies present. This study concludes tha t even when there is advanced diffuse replacement of splenic cords wit h amyloid on light microscopy, the ''pitting'' function of the spleen appears to be preserved in most cases. The absence of a hyposplenic bl ood picture cannot be equated with normal splenic cord histology in pa tients with systemic amyloidosis.