A 64-year-old woman with mild bilateral parotid gland swelling and bil
ateral lower extremity purpura was admitted for evaluation of xerostom
ia and pancytopenia. The patient had an increased erythrocyte sediment
ation rate, pancytopenia, and positive tests for antibodies to nuclear
antigen, SS-A, and SS-B. Impaired cell-mediated immunity was also pre
sent. Bone marrow aspiration showed a hypoplastic marrow with an incre
ased percentage of lymphocytes. A positive Schirmer's test and keratoc
onjunctivitis were also noted. A diagnosis of primary Sjogren's syndro
me was made by sialography and histological salivary gland findings. T
herapy with prednisolone improved the pancytopenia. Addition of the pa
tient's peripheral blood mononuclear cells to cultures of bone marrow
mononuclear cells derived from a healthy volunteer dose dependently in
hibited colony formation, including mixed hemopoietic colonies. On the
other hand, addition of the patient's serum failed to inhibit colony
formation by normal bone marrow mononuclear cells. These results sugge
sted that one of the causes of pancytopenia in primary Sjogren's syndr
ome might be mediated by the inhibition of mononuclear cells to the he
mopoietic progenitors.