1, stool collection requirements (1) stool routine (RT) and occult blood (or occult blood, OB) test Pick a small amount of fresh stool (about the size of a small soybean) with a small spoon in the container, should choose the part with pus and blood, mucus or color abnormalities, such as no abnormalities, can be taken from different parts of the stool surface and multiple parts of the stool depth, the amount of specimens generally 30 to 50mg, put into a dry clean covered The specimen should be placed in a dry, clean and covered plastic box and sent for examination within 1 hour. If no stool is available and the examination is necessary, the stool can be obtained by anal finger examination. The stool after enema is often too dilute and mixed with oil droplets and so on, and is not suitable for testing. (2) Specimens for fecal parasite examination The examination of amoebic trophozoites should be done immediately after defecation by taking material from the purulent or dilute part and sending it for examination immediately. When patients keep specimens at home, insulation measures should be taken during the examination, because amoebae can lose their motility at low temperatures and thus should not be detected. When examining pinworm eggs, swab the specimen from the crease around the anus in the early morning before defecation and send the specimen for immediate examination of the parasite eggs. The specimen should be sent for examination for 3 consecutive days to avoid missing detection due to periodic oviposition of certain protozoa or helminths. (3) Stool microbiological examination specimens should be used in sterile covered containers. Common bacterial culture: take more than 3g of stool with pus, blood and mucus, and more than 3mL of liquid stool in a sterile bottle and send it for examination immediately. Clostridium difficile culture and Clostridium difficile toxin detection: stool specimens should be filled with the entire sterile vial, immediately sent for testing. 2, stool collection precautions (1) specimens should be fresh, the specimen should be sent immediately after taking the specimen, not more than 1 hour. Specimens can be left for a long time due to pH and digestive enzymes and other factors in the decomposition and destruction of cellular components in the stool. Stool specimens should not be wrapped in toilet paper, please directly into the non-absorbent stool box to prevent water loss cells are destroyed. (2) The specimen should not be mixed with urine, moreover, the fecal specimen should not be taken from the urinal or potty, and the fecal specimen should not be taken from the diaper because urine can kill the tender protozoa in the feces and can increase the result of trypsin activity examination in the feces. (3) should avoid mixing urine, water, other substances, so as not to destroy the organic fraction, so that the pathogenic bacteria die. Fecal specimens should also not be mixed with plants, soil, sewage, etc., because saprophytic protozoa, fungal spores, plant seeds, pollen can easily confuse the experimental results. (4) occult blood test should be avoided in the test 3 days before taking a large amount of vitamin C, abstain from animal food, blood food, and forbidden to take iron, bismuth, avoid mixing with menstrual blood, urine, such as bleeding from the mouth and nose have swallowed will also affect the results. Should be sent for testing for 3 consecutive days.