WEEK 4: DIRECT FECAL SMEAR (DFS) AND CELLULOSE TAPE SWAB

• The presence of parasite with intestinal in origin is primarily identified through direct examination of stool using :

  1. Wet mount
  2. Concentration techniques
  3. Permanently stained smear
  4. Culture
• Examination of (3) three specimens collected every other day is considered the minimum necessary to perform an adequate O&P evaluation
• For G. lamblia, and Strongyloides stercoralis, up to (7) seven O&P examinations must be performed for optimal detections
• Lugol’s iodine is used to visualize diagnostic characteristics of protozoan cysts.
• Specimen needed:

  • Pea- sized specimen

  • Approximately 3 to 5 grams (3-5g) of stool

  • Collected in a clean, dry, waterproof, wide mouth with a

  tight-fitting lid collection container.
• Color – observe the color of the specimen (e.g Brown, Light brown, etc.)
• Consistency :

  Soft

  Semi-soft

  Formed

  Semi-formed - Mucoid

  Watery
• Color - Possible cause

  Black -UpperGI bleeding, Iron therapy, Charcoal, Bismuth(antacids)
• color - possible cause

  Red - LowerGIbleeding, Beets and food coloring , Rifampin

    
• color - possible cause

  Pale yellow, white, gray- Bile ductobstruction, Barium sulfate
• color - possible cause

  Green- Biliverdin/oral antibiotics, Green vegetables
• color - possible cause

  Bulky / Frothy - Bile ductobstruction, Pancreaticdisorders
• color - possible cause

  Ribbonlike - Intestinal constriction
• color - possible cause

  Mucus or blood streaked mucus- Colitis, Dysentery, Malignancy, Constipation
• Pinworm infection (enterobiasis) occurs world-wide and affects person of all ages and socioeconomic levels.
• Enterobius vermicularis is the scientific name of Pinworm.
• Heavy infection: a secondary bacterial infection can occur due to irritation and scratching of the anal area.
• ENTEREBIUS VERMICULARIS (Oxyuris vermicularis)

  Common name: Pinworm, Seatworm, Social worm, Society worm
• ENTEREBIUS VERMICULARIS (Oxyuris vermicularis)

  Mode of transmission : Inhalation, Ingestion, Autoinfection (External), Sexual (Transmission)
• Enterobius Vermicularis egg

  • Elongated,flattenedononeside

  • Football-shaped, D-shaped, “Itallian bread / Baguette

  ova.”

  • Doublelayered
• SCOTCH TAPE SWAB

  • Also known as the Cellulose Tape Swab Technique/ Graham’s Scotch Adhesive Tape swab; Gold standard for diagnosis of E. vermicularis.
• A piece of transparent adhesive tape is pressed firmly against the perianal skin, and the adhesive surface of the tape is spread on a glass slide
• SCOTCH TAPE SWAB

  At least 4-6 consecutive negative tapes are required to rule-out the infection.
• Adult female Enterobius vermicularis migrates out of the anus at night and deposits her eggs over the perianal area.
• Eggs can be collected for examination using cellophane tape procedure for the recovery of the said worm.