While "T. whipplei" is categorized with the Gram-positiveActinomycetota, the organism is commonly found to be Gram-positive or Gram-indeterminate when stained in the laboratory.[1]Whipple himself probably observed the organisms as rod-shaped structures with silver stain in his original case.[4]
^Whipple GH. (1907). "A hitherto undescribed disease characterized anatomically by deposits of fat and fatty acids in the intestinal and mesenteric lymphatic tissues". Johns Hopkins Hospital Bulletin. 18: 382–91.