DR RONALDA DE LACY. WHY IS IT DONE? Colour Consistency Frequency Blood Bacteria Viruses Parasites Fungal Pancreatic function Intestinal malabsorption.

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DR RONALDA DE LACY Slide 2 WHY IS IT DONE? Colour Consistency Frequency Blood Bacteria Viruses Parasites Fungal Pancreatic function Intestinal malabsorption Inflammatory markers Slide 3 STOOL COLOUR Slide 4 Slide 5 STOOL CONSISTENCY Slide 6 STOOL FREQUENCY Breastfed infants stool after every breastfeed - once to twice a week Children on average 1 to 2 stools per day Some children might have a stool every 2 nd day Slide 7 BLOOD FRESH BLOOD Lower GIT bleed- anal fissure - rectal haemorrhoids - polyps - inflammatory bowel disease - infections i.e. Shigella, salmonella - meckels diverticulum - intussception - NEC Slide 8 BLOOD ALTERED BLOOD (MALAENA) Upper GIT bleed- oesophagitis - mallory-weiss tear - gastritis - ulcersgastric, duodenal, small bowel - vascular malformations - anastomotic sites Slide 9 BACTERIA SHIGELLA Gram-negative rod Nonspore forming, non-motile Four serogroups- S. Dysenteriae (12 serotypes) - S. Flexeneri (6 serotypes) - S. Boydii (18 serotypes) - S. Sonnei (1 serotype) S. Flexeneri most frequently isolated in developing world 60% of cases S. Sonnei most frequently isolated in developed world 77% of cases Slide 10 SHIGELLA Slide 11 BACTERIA SALMONELLA Gram-negative rod Nonspore forming, motile Many serotypes Slide 12 SALMONELLA Slide 13 BACTERIA CHOLERA Only infects humans Transmission by faecal contamination of water and food Organism secretes an enterotoxin Results in watery diarrhoea Slide 14 CHOLERA Slide 15 BACTERIA CAMPYLOBACTER Gram-negative rod- comma or S-shaped Transmission is faecal-oral Cattle, chickens and dogs are sources Slide 16 CAMPYLOBACTER LIFECYCLE Slide 17 BACTERIA YERSINIA ENTEROLITICA Gram-negative oval rod Contaminated food Enterocolitis Slide 18 BACTERIA CLOSTRIDIUM DIFFICILE Antibiotic use Fresh stool sample Slide 19 BACTERIA MYCOBACTERIA Tuberculosis Transmission by respiratory droplets Mainly respiratory disease Dissemination can result in intestinal involvement Bovis Transmission by unpasteurised cows milk Intestinal involvement Difficult to culture from stool-need tissue Slide 20 VIRUS ROTAVIRUS RNA virus Most common cause for diarrhoea Vaccine available Diagnosis antigen testing on the stool Slide 21 ROTAVIRUS Slide 22 VIRUS ADENOVIRUS DNA virus 31 antigenic types High swinging fevers Pneumonia Conjunctivitis Diarrhoea Diagnosis antigen testing on the stool Slide 23 ADENOVIRUS Slide 24 PARASITES ENTEROBIUS VERMICULARIS Pinworm infection Lifecycle confined to humans Eggs recovered from peri-anal area with tape Adult worms may be found in the stool Slide 25 ENTEROBIUS VERMICULARIS Slide 26 ENTEROBIUS VERMICULARIS(PINWORM) Slide 27 PARASITES ASCARIS LUMBRICOIDES Transmission-eating eggs in contaminated soil Diagnosis- oval eggs in the stool or adult worms seen Slide 28 ASCARIS LUMBRICOIDES EGG Slide 29 ASCARIS LUMBRICOIDES LIFECYCLE Slide 30 PARASITES TRICHURIS TRICHURIUM Whipworm infection Transmission-eating eggs in contaminated soil Diagnosis- barrel-shaped eggs in the stool Slide 31 TRICHURIS TRICHIURA EGGS Slide 32 TRICHURIS TRICHURIUM LIFECYCLE Slide 33 PARASITES TAENIA SOLIUM Ingestion of larvae in undercooked pork Diagnosis- proglottids in stool gravid proglottids have 5-10 primary uterine branches TAENIA SAGINATA Ingestion of larvae in undercooked beef Diagnosis- gravid proglottids have 15-20 primary uterine branches Slide 34 TAENIA EGG Slide 35 TAENIA SAGINATA FOUR SUCKERS NO HOOKS Slide 36 TAENIA SOLIUM FOUR SUCKERS DOUBLE ROW OF HOOKS Slide 37 TAENIA LIFECYCLE Slide 38 PARASITES-PROTOZOA GIARDIA LAMBLIA Flagellated protozoan Waterborne transmission Faecal-oral route Infects the small intestine Difficult to isolate, need minimum of 3 stool specimens Diagnosis- trophozoites or cysts in diarrhoeal stools - trophozoites- pear-shaped, 2 nuclei, 4 pairs of flagella, suction disk Slide 39 GIARDIA LAMBLIA TROPHOZOITE Slide 40 PARASITES-PROTOZOA CRYPTOSPORIDIUM Coccidian protozoa Waterborne transmission Direct person to person contact Immunocompromised patients Diagnosis- oocysts in faecal smears Slide 41 CRYPTOSPORIDIUM OOCYSTS Slide 42 CRYPTOSPORIDIUM OOCYSTS-EM Slide 43 Slide 44 PARASITES-PROTOZOA ENTAMOEBA HISTOLYTICA Transmission-faecal-oral route, contaminated food and water Diagnosis- trophozoites in diarrhoeal stools - cysts in formed stools 4 nuclei Slide 45 ENTAMOEBA HISTOLYTICA CYST Slide 46 PARASITES-PROTOZOA ISOSPORA BELLI Faecal-oral transmission Immunocompromised patients Diagnosis-oocysts in faecal specimen Slide 47 ISOSPORA BELLI OOCYSTS Slide 48 Slide 49 FUNGAL CANDIDA ALBICANS Part of normal gut flora Overgrowth in diabetes, immunocompromised patients and prolonged antibiotic use. Diagnosis- oval yeast with a single bud in the stool Slide 50 CANDIDA ALBICANS Slide 51 PANCREATIC FUNCTION Faecal elastase >200ug/g faeces - normal Low in chronic diarrhoeaSlide 52 INTESTINAL MALABSORPTION CARBOHYDRATE MALABSORPTION Faecal reducing substances positive osmotic diarrhoea Faecal osmolar gap (FOG) serum osmolarity- 2x(faecal sodium + potassium concentration) FOG >100 mosm/l osmotic diarrhoea FOGSlide 53 INTESTINAL MALABSORPTION PROTEIN MALABSORPTION Stool alpha 1 anti-trypsin Need a pre-weighed container Clearance rate 0.8-5.4ml/24hrs Slide 54 INTESTINAL MALABSORPTION FAT MALABSORPTION 3 day faecal fat measurement Histology- free fat Steatocrit-not specific for free fat Slide 55 INFLAMMATORY MARKERS COLPROTECTIN Calcium and zinc binding protein Accounts for 30-40% of neutrophil cytosol Resistant to enzymatic degradation Strongly correlated with 111-indium labelled leucocytes References range- upper limit 2-9yrs 166ug/g faeces 10-59yrs- 51 ug/g faeces