Blood/Blood Cells and Cellular Components ›› Red Blood Cells ›› Abnormal

Red Cell Agglutinate*






Microscopic Features:
  • Irregular overlapping aggregate of RBCs
  • A cluster of overlapping RBCs (Non-linear overlapping RBCs)
Normal % blood-PB, marrow-BM, lymphoid tissue-LN:
  • PB: None
  • BM: None
  • LN: None
May Resemble:
  • Rouleaux
  • Thick area of a blood smear giving rise to overlapping RBCs
Differential Diagnoses:

Paroxysmal cold hemoglobinuria
Cold agglutinins
Elevated serum IgM M-spike as in Waldenstom 's macroglobulinemia
Plasma cell neoplasm associated with monoclonal IgM

Classic Immunophenotype:
  • N/A
Cartoon Image:



Misc:
  • This finding must be evaluated in the appropriate section of the peripheral blood smear (where RBCs are usually not touching each other). Typically associated with cold antibodies (usually IgM). Mostly due to reduced zeta potential (Note: the zeta potential between RBCs keeps them apart. Hence anything, usually relatively positively charged molecules such as immunoglobulins, that reduces this zeta potential will facilitate RBCs to aggregate or stack on top of each other).