Abstract
Two cases of pseudomelanosis duodeni were reported. First patient was 50 year old male. He had no underlying diseases and had no habit of taking particular drugs. Endoscopically black-brown spot were observed in the upper part of the duodenal bulb. Biopsied specimen revealed pigments in the lamina propria. The pigment was negative for PAS stain and iron stain, positive for Fontana-Masson stain. Result of electron microscopy showed that the pigment was located in the round lysosome as the fine electrondense particle. Second patient was 83 year old female with hypertension and anemia. Her medications included hydralazin, thiazide, reserpine and ferrous sulfate. Black-brown pigmentation was observed in the second portion of the duodenum as "peppered" like appearance endoscopically. Biopsied specimen revealed that pigments were negative for PAS stain, positive for iron stain and Fontana-Masson stain. Result of electron micro-scopy showed that the pigment was located in the irregular shaped lysosome as the electron-dense granule with lipid droplets. The second patient was a typical case of the pseudomelanosis duodeni, however the first patient was rather different from ever reported cases both in clinical and morphological aspects.
