JC117 (Paediatrics) - Diarrhea in children Flashcards
Differential diagnosis of acute-onset bloody stool, fever and abdominal cramps
Infective pathogens: Campylobacter Shigella Salmonella Enteroinvasive E.coli Enterohemorrhagic E. coli (O157:H7) Clostridium difficile Yersinia enterocolitis Vibrio parahaemolyticus
Ddx causative pathogens of watery vs bloody diarrhea
Watery:
Enterotoxin
Virus
Protozoan
Bloody with mucus:
Cytotoxin-producing bacteria causing mucosal inflammation
Enteric parasite
Outline history taking questions for acute diarrhea in children
- Confirm diarrhea: alteration in bowel movement with change in stool consistency to loose/ watery, and increase stool frequency and volume
- Character of diarrhea: watery vs bloody, presence of mucus
- Severity:
- Frequency
- Number of episodes
- Estimated amount/ trend over time - Any associated symptoms:
- Vomiting: appearance, frequency, volume, projectile
- Fever
- Appetite and recent food intake
- Abdominal pain/ colic
- Irritability - Risk of dehydration
- Source of infection: TOCC
- Past health, recent management and birth history
Symptoms of dehydration in children
Risk factors of dehydration
Symptoms:
Dry lips
Cool limbs
Urine output
Risk factors:
Children <1 year, particularly <6 months
Infants of low birthweight
Frequent profuse watery diarrhea
Vomiting (>2 in previous 24hrs)
Poor fluid intake: malnutrition, intolerance to fluid
Concurrent fever (increased insensible fluid loss)
Possible sources of infection causing diarrhea in children
Contacts having similar symptoms (most common)
Change in food content
Change in preparation: the person, the method, the utensils
‘Unhygienic food’, e.g. undercooked food, raw food, eating out
Nursery outbreak
Family member occupations:
a) Cooks, kitchen workers (contact with raw food or carriers of Salmonella)
b) Health care workers (exposure to enteric pathogens)
Causes of diarrhea in an immunocompromised child
Chemotherapy, prolonged antibiotics use
» hospital-acquired, multiple antibiotic-resistant enteral bacteria
X-linked agammaglobulinemia (absent B cells, reduced humoral immunity)»_space; Giardia infection
Antimicrobial-associated diarrhea»_space; Clostridium infection
Birth, family and social history relevant to diarrhea in a child
Birth:
Preterm babies at risk of necrotizing enterocolitis
bowel surgery: short gut syndrome, blind loop syndrome (bacterial overgrowth)
Family history:
Recent GE, GI symptoms in immediate family members
Chronic diarrhea in childhood
Inborn errors of immunity: cellular immunodeficiency or lack of IgA protective mucosal response
Social history (who look after child, change in carer)
Ddx acute diarrhea in a child
Infective:
Bacterial vs. virus (majority in children)
Secretory (toxins cause secretion of electrolytes and fluids into gut)
Inflammatory (cytotoxic effect damages mucosal cells, influx of white
cells and immune cells)
Food intolerance
Osmotic agents
Drugs
Acute infective gastroenteritis in children
Most common causative pathogens
Virus: Rotavirus
Bacteria:
Campylobacter spp.
Salmonella spp.
E. coli: O157, Non-O157
Protozoa: Cryptosporidium parvum (uncommon, specific to T cell defects)
List all viruses that can cause Acute infective gastroenteritis in children
Rotavirus
Norovirus Adenovirus group F Calicivirus Astrovirus Small round structured virus
List all bacteria that can cause Acute infective gastroenteritis in children
Campylobacter spp.
Salmonella spp.
E. coli
Shigella spp. Clostridium difficile Clostridium perfringens Staphylococcus aureus Bacillius spp. Vibrio spp. Yersinia spp. Aeromonas spp.
Pathogens a/w traveler’s diarrhea
Most common: Salmonella
Others: Campylobacter, E. coli, Cryptosporidium
Shigella, Giardia, Entamoeba (Indian subcontinent, sub-Saharan, southern Africa)
Ddx non-gastrointestinal infection causes of diarrhea and vomiting
1. Non-enteric infections: Pneumonia Urinary tract infection Meningitis Acute otitis media Toxic shock syndrome
- Non-infective gastrointestinal disorders
Ulcerative colitis
Crohn’s disease
Coeliac disease - Surgical disorder
Bowel obstruction
Intussusceptions
Ischemic bowel - Drug-related: antibiotics esp.
Key symptoms and signs of meningitis in children
Key symptoms Persistent vomiting Altered consciousness Irritability Photophobia
Key signs
Petechial purpuric rash
Neck stiffness
Bulging fontanelle in infants
Key symptoms and signs of toxic shock syndrome in children
Key symptoms
Non-specific muscle aches
Faintness
Key signs
Clinical shock
Red non-specific rash
Possible site of bacterial entry (e.g. small burn, injury)
Factors a/w more prolonged course of infective gastroenteritis
Co-infection of enteric pathogen
Bloody and/ or mucoid stools
Malnutrition
Indiscriminate use of antibiotics
Explain why infants are more susceptible to dehydration from diarrhea
A greater portion of their bodies is made of water
Higher surface to mass ratio - higher loss through skin
Children have a high metabolic rate
A child’s kidneys do not conserve water as well as an adult’s kidneys
Low ability to express thirst
Define mild, moderate and severe dehydration in a child
Signs to define severity of dehydration
% weight loss:
Mild, 3-5%
Moderate, 6-9%
Severe, >10%
Signs:
- BP, HR, rhythm
- Skin turgor
- Sunken fontanelle
- Mucous membrane dryness
- Sunken orbits
- Cool, mottled extremities with delayed capillary refill
- Mental status: lethargy or coma
- Urine output
- Thirst
Electrolyte disturbance associated with dehydration in children with severe diarrhea
Manifestations
Hypernatremic dehydration:
- dehydration with plasma Na >150mmol/L
- Severity of dehydration often underestimated compared to normo- natremic dehydration (fluid drawn into subcutaneous tissue»_space; reduced skin turgor not apparent)
Manifestations: Jittery movement Increased muscle tone Hyperreflexia Convulsions Drowsiness/ coma
Indications for hospital admission of a child with diarrhea
- Red flag signs for significant dehydration:
Appears to be unwell/ deteriorating
Altered responsiveness (e.g. irritable, lethargic)
Sunken eyes
Tachycardia
Tachypnea
Reduce skin turgor - Risk factors for significant ongoing loss, especially with severe vomiting compromising the chance of success with oral rehydration (give IV fluid)
- Patients with grossly bloody stool
- Patients with immunocompromised states at risk of opportunistic infection
First-line investigations for child with severe diarrhea
Assess dehydration, electrolyte imbalance, acid-base imbalance:
- Measure plasma Na, K, renal function (urea, creatinine) & glucose if:
- Require IV fluid therapy (adjust Na, K levels)
- Symptoms/signs suggest hypernatremia
- Infant with unexplained drowsiness – rule out hypoglycemia - Measure venous blood acid-base status and chloride concentration if shock
- Stool microbiological investigations:
- Indicated if diarrhea and systemic illness, sepsis
- Presence of blood and mucus in stool
Acid-base disturbance a/w severe diarrhea in children
Severe diarrhea causes:
Loss of bicarbonate in diarrhea
Lactic acidosis in hypovolemic shock
Measure anion gap (base excess = Na + K – Cl – HCO3):
Raised anion gap: impaired tissue perfusion (end organs respire anaerobically and produce lactate»_space; negative ion accumulation increase base excess)
Normal anion gap: bicarbonate loss
Indications for stool microbiological investigation for diarrhea in a child
Most acute GE in children = viral in origin and self limiting
Indicators for extensive stool microbiology workup:
a) Child with diarrhea and systemic illness/ sepsis
b) Presence of blood and mucus in stool: EHEC, antibiotic-associated pseudomembranous colitis, Bacterial/ amoebic dysentery
c) Suspect traveler’s diarrhea
d) Immunocompromised hosts (opportunistic organism)
e) Diarrhea with prolonged course
Which pathogens that cause diarrhea require extensive microbiological workup
Bacterial/ amoebic dysentery (Campylobacter, Shigella,
EIEC, EHEC, Vibrio parahaemolyticus, Entamoeba histolytica)
Enterohaemorrhagic E. coli O157:H7 (associated with hemolytic uremic syndrome)
Antibiotic-related pseudomembranous colitis, caused by Clostridium difficile
opportunistic organism in immunocompromised child
Traveler’s diarrhea
General management options for diarrhea in a child
- Prevention of dehydration or rehydration therapies
- ORS
- Intraosseous fluid therapy
- Treatment of hypernatremic dehydration
- Intravenous fluid therapy - Nutritional management - early oral feeding
- Symptom relief:
- Anti-emetics
- Anti-diarrheal agents - Probiotics
- Antibiotics
General fluid management in paediatric gastroenteritis without dehydration
Prevent hydration:
a) Continue breastfeeding and other milk feeds
b) Encourage fluid intake
c) Discourage consumption of fruit juices and carbonated drinks (sugar draws fluid into gut lumen and worsens diarrhea)
d) Offer oral rehydration solution (ORS) as supplemental fluid
Fluid management for paediatric gastroenteritis with clinical dehydration
- ORS first-line rehydration
- ORS for first 3-4 hours of rehydration
- Continue breast feeding and milk feeding
- Avoid fruit juices or carbonated drinks
Compare the content of conventional ORS solution and Rice-based ORS
Rice-based ORS:
- Lower Na and Cl load
- Low glucose with rice powder substitute
- Sam citrate concentration
Rice powder rationale:
- rice powder broken down into glucose by polysaccharidase and disaccharidase at brush border of intestinal villi rather than in gut lumen
- Na-glucose co-transporter promotes absorption of salt and water across enterocytes
- Associated with reduction in duration of diarrhea in children, better control of cholera
Why is low-osmolarity ORS solution better for treatment of diarrhea?
High osmolarity/ High Na ORS increases osmotic load in gut lumen and increase fluid loss
Low osmolarity ORS reduces need for IV fluid treatment, and reduces stool output and vomiting
Oral rehydration strategy for paediatric diarrhea and dehydration
Small, frequent feeds
Replace fluid deficit over 4 hours*** and then give maintenance fluid
Monitor ongoing loss and replace accordingly to body weight loss***
Reassess and adjust strategy according to tolerance and response
Indications of more aggressive IV fluid therapy for severe diarrhea in a child
Signs of shock
Impaired conscious state (can be a result of shock)
Red flag symptoms of deterioration and dehydration
Failed ORS due to intolerance/ vomiting
Paralytic ileus due to anti-motility agents
IV rehydration strategy for paediatric diarrhea and dehydration
IV rehydration over 3-6 hours with maintenance fluid replacement after
Early introduction of oral rehydration during IV fluid therapy (as early as tolerable)
Treatment of hypernatremic dehydration caused by severe diarrhea in a child
isotonic solution 0.9% NaCl for fluid deficit replacement + maintenance
Replace fluid deficit slowly – over 48 hours*** SLOWLY to avoid central pontine myelinolysis **
Monitor plasma sodium frequently – reduce it at a rate <0.5mmol/L per hour
Complication of correcting hypernatremic dehydration too quickly?
central pontine myelinolysis
Serum Na level changes too quickly, causing osmotic demyelination and draws fluid outside CNS
Must monitor plasma sodium frequently and reduce at rate under 0.5mmol/L per hour
Urgent treatment of hypovolemic shock caused by severe diarrhea and dehydration
- Rapid IV infusion of 0.9% NaCl, 20mL/kg
if persistent signs of shock (low BP, impaired perfusion): Another rapid IV infusion of 0.9% NaCl, 20ml/kg
Consider possible causes of shock other than dehydration - If signs of shock resolved: continue rehydration with IV fluid
- If persistent signs of shock: consult intensive care specialist
Fluid management after rehydration therapy for paediatric diarrhea
Continue breastfeeding and milk feeds
Encourage fluid intake
Avoid fruit juices/ carbonated drinks
Prevent recurrence of dehydration by replacing ongoing loss from diarrhea with additional ORS
Restart oral rehydration therapy if dehydration recurs after rehydration
Nutritional management for paediatric diarrhea
Re-introduce usual feeding early, including solid food as long as tolerable
Give full-strength milk as usual (no evidence that diluted milk is of benefit)
No benefit from special milk formulas, e.g. lactose-free/ soy-based formula
Symptomatic relief options for diarrhea
ALL of these agents are not recommended for routine use in children
Anti-emetics:
- Ondansetron (zofran): potent, highly-selective 5-HT3 receptor antagonists; oral
- Metoclopramide (maxolon): anti-dopamine D2, weak anti- 5HT3 activity
- Promethazine (phenergan): anti-histamine H1, anti- cholinergic, anti-dopaminergic activity
Anti-diarrheal agents:
Adsorbents, e.g. kaolin, smectite
Anti-motility agents, e.g. loperamide
Justify whether routine use of symptomatic relief medication for paediatric diarrhea is needed
Ondansetron (zofran): Routine use not recommended
- Frequency of stool passage increases (retained fluid and toxins that should be eliminated)
Metoclopramide, Promethazine: Use in children NOT RECOMMENDED
- Significant adverse effects (e.g. dystonic reactions of facial and skeletal muscles, oculogyric crisis)
Anti-diarrheal agents: Not recommended
Potentially serious adverse side effects: e.g. Abdominal distension, Ileus, Drowsiness (loperamide), impaired clearance of pathogens and toxins
Probiotics for paediatric diarrhea
- Content
- MoA to treat diarrhea
E.g. Lactobacillus, Bifidobacillus, Saccharomyces yeast
Possible mechanism:
Compete with pathogens for binding sites and substrates
Lower intestinal luminal pH
Upregulate genes mediating immunity
Produce trophic short-chain fatty acids and promote mucosal cell growth and differentiation
Antibiotics for paediatric diarrhea
- Recommended use/ indications for use
Most acute GE in children = self-limiting illness caused by viral infection, do not need antibiotics
Indications for antibiotics use:
septicemia/ Extra-intestinal spread of bacterial infection
Specific pathogens:
Patient is <6 months/ malnourished/ immunocompromised with Salmonella gastroenteritis
Clostridium difficile associated pseudomembranous enterocolitis (metronidazole/ oral vancomycin)
Giardia lamblia
Dysentery by Shigella (IV 3rd generation cephalosporin – ceftriaxone, cefotaxime) or Amoebic dysentery
Cholera
Indications for discharge after treatment of paediatric diarrhea
Indicators of safe discharge:
Rehydration completed
Minimal risk for recurrence of dehydration
Uncomplicated disease course
Other considerations:
Reliable carer: capability of child care
Understanding of the carer to your treatment plan
Home care plan for paediatrics diarrhea
- Continue usual feeds, encourage frequent hydration
- Discourage consumption of fruit juices and carbonated drinks
- Offer ORS solution as supplemental fluid (Sachets to take home)
- Seek medical hydration if signs of dehydration, or atypical/ prolonged illness
