Ricardo A. Caicedo, MD Pediatric Gastroenterology University of Florida

Ricardo A. Caicedo, MD
Pediatric Gastroenterology
University of Florida
Diarrhea
Increase in frequency and water
content of stools
MECHANISM
Examples
MALABSORPTION
Celiac disease, Rotavirus
OSMOTIC
Lactase deficiency
SECRETORY
Cholera, C. difficile toxin
HYPERMOTILITY
IBS
INFLAMMATORY
IBD, Shigella
Acute Diarrhea
• Infection
– Viral gastroenteritis
• Rotavirus
• Enterovirus, adenovirus
• Norwalk virus
– Bacterial enterocolitis
•
•
•
•
Shigella, Salmonella
Yersinia, Campylobacter
E.coli – enteroinvasive
C. difficile
– Foodborne
• S.aureus, Bacillus cereus
• E. coli – enterotoxigenic
– Other: UTI, OM
• Inflammatory
– Hemolytic Uremic Syndrome (HUS)
– Henoch-Schonlein Purpura (HSP)
• Anatomic
– Intussusception
– Appendicitis
• Toxic Ingestion
– Iron, mercury, lead
• Other
– Antibiotic-induced
– Hyperconcentrated infant formula
– Overfeeding infants
Chronic Diarrhea
• Infection – parasitic
– Giardia lamblia
– Entamoeba histolytica
– Cryptosporidium parvum
• Inflammatory
– Milk protein intolerance
– Food allergy
– IBD
Duration > 2 weeks
• Malabsorption
– Celiac disease
– Cystic fibrosis
– Bacterial overgrowth
• Osmotic
– Lactase deficiency
• Primary
• Secondary post-infectious
– Excessive fructose intake
– Laxative overuse
Parasitic
Organism
Sources
Duration
Giardia
Entamoeba
Cryptosporidium
Fecal-oral, water supplies
2 wks – years
Same
Weeks
Same, plus petting zoos,
swimming pools
2 wks
Cyclospora
Water, unpasteurized apple 1wk-1month
cider
Isospora
Strongyloides
Fecal-oral, water
> 2 wks
Fecal-oral
Appalachia
same
Blastocystis hominis
Pathogenic?
Keating J (2005) Pediatr Rev 26: 5-13.
Tan KS et al (2002) Int J Parasitol 32: 789-804
Giardiasis
• Presentation
– Watery, foul stools
– Abdominal distention
• Bloating, flatulence
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–
–
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Crampy abdominal pain
Malaise, weakness
Nausea/vomiting
Anorexia, wt loss
• Risk factors
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–
–
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Well water
Daycare
Public pools, summer camp
Immunodeficiency
• Diagnosis
– Stool antigen test
• Greater sensitivity than O+P
• Simpler than duodenal bx
– Often overlooked
• Fever, WBC, eosinophilia rare
• Natural history
– Most become asx by 6 wks
– Frequent re-infx (up to 35%)
– Few develop prolonged diarrhea
with wt loss and growth failure
• Treatment
– Flagyl 15 mg/kg/d X 10 d
• Albendazole, furazolidone
• Asx carriers usually not treated
Prolonged Viral/Bacterial Diarrheas
Agent
Sources
Adenovirus, Rotavirus,
CMV
Duration
Avg. 11 d
Months in immunodeficient
C. difficile
Abx, nosocomial
Campylobacter
Raw poultry, unpasteurized 5 d - weeks
milk, contaminated water
Salmonella
Poultry, fecal-oral
Months in infants
Yersinia
Raw pig intestines, fecaloral
3 wks -3 months
Aeromonas
Untreated water
1 wk – 1 yr
Keating J (2005) Pediatr Rev 26: 5-13.
Relapses in 10% of cases
Prolonged Diarrhea in Infants
• Prolonged/recurrent
diarrhea
• Failure to gain weight
Sucrase-isomaltase deficiency
“Slick Gut” Syndrome
– Intractable diarrhea of
infancy, postenteritis
enteropathy
– Metabolic acidosis
– Treatment
due to malrotation
OTHER:
Immunodeficiency
CF
VIPoma
Abetalipoproteinemia
Celiac disease
Congenital intestinal
lymphangiectasia
• Initial lactose-free, sucrosefree formula
• Elemental formula
• TPN
= diagnosable by SB bx
Small bowel biopsy
Tufting enteropathy
No effective tx
Congenital
lymphangiectasia
Protein losing enteropathy
Villous clubbing
Subepithelial bleb
MCT and high protein diet
Microvillus inclusion disease
Neonatal
Apical membrane autophagocytosis
Consanguinity
TPN-dependence, SB Transplant
Toddler’s diarrhea
• Chronic nonspecific diarrhea of childhood
• Symptoms
– Explosive loose stools
– Contain food particles
– Frequent stools, decline as day goes on
• Management
– Verify normal growth and absence of red flags
• Blood in stool, persistent fever, anemia
– Exclude celiac disease (tTG) and Giardia
– Trial of dietary modification
• Restrict fructose and/or lactose
Diarrhea in older children
• OSMOTIC
– Lactase deficiency
• Primary
– African, Asian, Hispanic
• Secondary
– Postenteritis
– Laxative overuse/Poisoning
• INFLAMMATORY
– Infectious
– IBD
• FUNCTIONAL/hypermotility
– IBS
– CNSD (Toddler’s)
• MALABSORPTIVE
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–
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Celiac disease
CF
Pancreatic insufficiency steatorrhea
Chronic cholestasis
Bacterial overgrowth
Zinc deficiency
Intestinal lymphangiectasia
• Cong. Heart Dz (Fontan physiol)
• Tumor or radiation
• SECRETORY
Secretory diarrheas
•
•
•
•
Voluminous watery
Persists despite bowel rest
Massive efflux of fluid/salt
Stool electrolyte content
similar to serum
• WDHA syndrome
– Watery diarrhea
– Hypokalemia
– Alkalosis
• DIFFERENTIAL DX
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–
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Cholera
C. difficile
Severe mucosal injury
Short bowel syndrome
Secretory tumors
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•
•
•
•
•
Carcinoid
Gastrinoma
Ganglioneuroma
Neuroblastoma
Pheochromocytoma
VIPoma
Zinc deficiency
• Acrodermatitis enteropathica
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–
–
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Perineal and perioral rash
Chronic diarrhea & undernutrition
Low serum Zn and alk phos
Primary
• Rare, recessive, mutation in Zn transporter
– Secondary
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•
•
•
•
•
CF
Crohn’s
Anorexia nervosa
Dialysis
Chronic TPN
Exclusively breastfed preterms
– Tx = longterm Zn supplementation
Immunodeficiency
CONDITION
Immunosuppression
DIARRHEA
CMV colitis, Cryptosporidium, Isospora,
Entamoeba, Microspora, Cyclospora
HIV
Cryptosporidium, Giardia, +/- VIP-oma
SCID
CGD
Wiskott
CVID
Hyper IgM
Selective IgA deficiency
MHC II deficiency
50% have protracted diarrhea in infancy
Crohn-like colitis early in life
IBD-like early in life
Campy, Giardia
50% have chronic diarrhea
Increased risk of chronic giardiasis
Death in infancy due to severe malabsorption
Approach
• Impact of diarrhea
– How is the infant/child growing?
– How is symptom affecting child’s life?
• Mechanism of diarrhea
– Description of stool
• Blood? Oily? Food particles?
• Frequency
– Diet and exposures
• Complete physical exam
– Attention to skin, LN, spleen
• Screening and diagnostic tests
Screening tests
• BLOOD
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Electrolytes
Total protein/albumin
Liver tests
CBC
ESR
Celiac serology (tTG)
Vitamin levels
• B12, FA, Fe
• A, D, E
• STOOL
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Guaiac
pH and reducing substances
Spot fat stain
Gram stain/Culture
Giardia Ag
O+P
C. diff toxin
Osmolarity
Electrolytes
Secretory vs. Osmotic
Osmotic Gap: 290 – {2 ([Na+] +[ K+])}
Stool Na > 70
Osmotic Gap < 100
Persists while NPO
Stool Na < 70
Osmotic Gap > 100
Decreases when NPO
Malabsorption studies
• FAT
• CARBOHYDRATE
– Spot fecal fat stain
– Quantitative 72 hr
• Total excretion > 5g fat/24 h
• Coefficient of absorption =
(fat ingested –
excreted)/ingested X 100%
• PROTEIN
– Fecal A1AT
• Suggests mucosal disorder
such as celiac disease
– Stool pH < 5.5
– Reducing sugars
• Lactose, maltose, fructose,
galactose
– Breath hydrogen test
• H2 produced by bacterial
fermentation of undigested
CHO
• Rise in H2 > 20 ppm above
baseline: malabs.
• Elevated baseline or ∆20
ppm w/in 30 min: overgrowth
Barney Beagle
Thank You!