Chapter 6 Stool tests

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Chapter 6 Stool tests

• Stool examination is a basic method for getting
  clues of inflammation, bleeding, obstruction,
  tumor and parasite infection in gastrointestinal
  tract and digestive system in clinic. This part
  of tests include the general property of stool,
  microscopic examination , chemical (occult blood)
  test and bacteriological tests.

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• General property of stool

• Microscopy

• Occult blood test

• Bacteriological examination

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General property of stool

• watery stool infectious and non-infectious
  diarrheas
• mucus stool inflammatory diarrheas
• pyohemochezia stool bacterial dysentery,
  ulcerative colitis, Crohns disease,rectum
  carcinoma, colon carcinoma
• hematochezia stool bloody diarrhea, hemorrhoid
  ischemic colitis, amebie dysentery, rectocolitis
• melena or tarry stool a sign of bleeding from an
  upper digestive tract gastric ulcer, carcinoma
  of stomach
• kaolin stool biliary obstructio
•  

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Microscopy

• Cells
• WBCnormal 01/HP, gt15/HP inflammation
• RBCnormal0, RBC () dysentery,
  carcinoma of GI, ulcerative colitis
• macrophagenormal 0, () colitis , bacterial
  dysentery
• tumor cell colon carcinoma, rectum carcinoma
• Food residue
• Ovum of parasite roundworm, hookworm , tenia

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Occult blood test
GI bleeding is a common clinical problem. Blood
loss ranges from occult bleeding of which the
patient is unaware to massive bleeding that
anyone would notice( melena or bloody stool).
Positive occult blood test is usually due to
chronic GI blood loss, both upper and lower GI
lesion such as peptic ulcer, stomach carcinoma,
and colon carcinoma. It is a screening test for
digestive carcinoma especially for elderly people
.
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Case analysis

• History and physical examination This patient
  was a 68-year-old man. For the previous 3 months
  he had complained of incresingly severe
  dizziness, shortness of breath, weakness and
  melena stool. On admisson to the hospital , the
  body temperature was 37.6 C. Slightly enlarged
  lymphnodes were palpable in the rght axilla and
  posterior cervical areas. The spleen and liver
  are not enlarged.

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Laboratory data Hb 75g/L, WBC 15109/L, PC
80109/L, stool tarry and soft, RBC 13/HP, WBC
2/HP, no special cell was found.

• Question
• What do you think this patient probably suffer
  from ?
• What do you plan to do next?
• why does this patient had developed medium
  anemia?