Gastroenteritis and dehydration in children

1. ACUTE GASTROENTERITIS AND
DEHYDRATION IN CHILDREN
BY ANNE E. ODARO
MCM/2017/69852

2. CLINICAL CASE
 Tina is a 6 month old bottle fed infant, brought to
your general practice surgery with a 12 hour history
of diarrhea (10 watery green stools without blood)
and vomiting (eight yellow non-bilious vomits). Her
mother is worried because she is irritable with fever
(38°C). Her brother, who attends nursery, has just
got over a bout of “gastroenteritis.” She is an active
baby with perianal excoriation and a weight of 5.5
kg. She has a sunken fontanel and decreased skin
turgor (pinch test 4 sec). She passes urine during
the examination. On review of her health record you
note she has lost 0.5 kg since last weighed two
weeks ago.
 WHAT IS THE MOST LIKELY DIAGNOSIS?

3. INTRODUCTION
 Acute gastroenteritis—diarrhoea or
vomiting (or both) of more than seven days
duration—may be accompanied by fever,
abdominal pain, and anorexia.
 Diarrhoea is the passage of excessively
liquid or frequent stools with increased
water content.
 Children with poor nutrition are at
increased risk of complications.

4. EPIDEMIOLOGY
 It is estimated that there were two billion cases of
gastroenteritis that resulted in 1.3 million deaths
globally in 2015.
 Children and those in the developing world are most
commonly affected.
 As of 2011, in those less than five, there were about
1.7 billion cases resulting in 0.7 million deaths, with
most of these occurring in the world's poorest
nations.
 Children less than two years of age frequently get six
or more infections a year that result in significant
gastroenteritis.

5.  In 1980, gastroenteritis from all
causes caused 4.6 million deaths in
children, with the majority occurring in
the developing world.
 Death rates were reduced significantly
(to approximately 1.5 million deaths
annually) by the year 2000, largely
due to the introduction and
widespread use of oral rehydration
therapy.

7. PATHOPHYSIOLOGY
 Adequate fluid balance in humans
depends on the secretion and
reabsorption of fluid and electrolytes
in the intestinal tract
 Diarrhea occurs when intestinal fluid
output overwhelms the absorptive
capacity of the gastrointestinal tract.

8. The 2 primary mechanisms responsible for
acute gastroenteritis are
 (1) damage to the villous brush border of
the intestine, causing malabsorption of
intestinal contents and leading to an
osmotic diarrhea, and
 (2) the release of toxins that bind to
specific enterocyte receptors and cause
the release of chloride ions into the
intestinal lumen, leading to secretory
diarrhea.

9.  Even in severe diarrhea, however, various
sodium-coupled solute co-transport mechanisms
remain intact, allowing for the efficient
reabsorption of salt and water.
 By providing a 1:1 proportion of sodium to
glucose, classic oral rehydration solution (ORS)
takes advantage of a specific sodium-glucose
transporter (SGLT-1) to increase the
reabsorption of sodium, which leads to the
passive reabsorption of water.
 Rice and cereal-based ORS may also take
advantage of sodium-amino acid transporters to
increase reabsorption of fluid and electrolytes.

12. ORGANISMS
Viruses (∼70%)
 Rotaviruses
 Noroviruses (Norwalk-like
viruses)
 Enteric adenoviruses
 Caliciviruses
 Astroviruses
 Enteroviruses
Protozoa (<10%)
 Cryptosporidium
 Giardia lamblia
 Entamoeba histolytica
Bacteria (10-20%)
 Campylobacter jejuni
 Non-
typhoid Salmonella spp
 Enteropathogenic Escheri
chia coli
 Shigella spp
 Yersinia enterocolitica
 Shiga toxin producing E
coli
 Salmonella typhi and S
paratyphi
 Vibrio cholerae
Helminths
 Strongyloides stercoralis

13. CLINICAL PRESENETATION: PATIENT Hx
 Determine the duration of diarrhea, the
frequency and amount of stools, the time since
the last episode of diarrhea, and the quality of
stools. Frequent, watery stools are more
consistent with viral gastroenteritis, while stools
with blood or mucous are indicative of a bacterial
pathogen. Similarly, a long duration of diarrhea
(>14 days) is more consistent with a parasitic or
noninfectious cause of diarrhea.
 Determine if there is an increase or decrease in
the frequency of urination as measured by the
number of wet diapers, time since last urination,
color and concentration of urine, and presence of
dysuria.

14.  Determine the duration of vomiting, the amount
and quality of vomitus (eg, food contents, blood,
bile), and time since the last episode of vomiting.
When symptoms of vomiting predominate, one
should consider other diseases such as
gastroesophageal reflux disease (GERD),
diabetic ketoacidosis, pyloric stenosis, acute
abdomen, or urinary tract infection.
 Determine the presence of fever, chills, myalgias,
rash, rhinorrhea, sore throat, cough, known
immunocompromised status. These may indicate
evidence of systemic infection or sepsis.

15.  Appearance and behavior: Elements include
weight loss, quality of feeding, amount and
frequency of feeding, level of thirst, level of
alertness, increased malaise, lethargy, or
irritability, quality of crying, and presence or
absence of tears with crying.
 Antibiotics: A history of recent antibiotic use
increases the likelihood of Clostridium difficile
infection.
 Travel: History of travel to endemic areas may
make prompt consideration of organisms that are
relatively rare in the United States, such as
parasitic diseases or cholera.

16. PHYSICAL EXAMINATION
 Elements of the physical examination are as follows:
 General - Weight, ill appearance, level of alertness,
lethargy, irritability
 HEENT (head, ears, eyes, nose, and throat) -
Presence or absence of tears, dry or moist mucous
membranes, and whether the eyes appear sunken
 Cardiovascular - Heart rate and quality of pulses
 Respiratory - Rate and quality of respirations (deep,
acidotic breathing suggests severe dehydration).
 Back - Flank/costovertebral angle tenderness
increase the likelihood of pyelonephritis

17.  Abdomen - Abdominal tenderness, guarding and
rebound, and bowel sounds; abdominal tenderness
on examination, with or without guarding, should
prompt consideration of diseases other than
gastroenteritis
 Rectal - Quality and color of stool, presence of gross
blood or mucous
 Extremities - Capillary refill time, warm or cool
extremities
 Skin - Abdominal rash may indicate typhoid fever
(infection with Salmonella typhi), while jaundice
might make viral or toxic hepatitis more likely; slow
return of abdominal skin pinch suggests decreased
skin turgor and dehydration, while a doughy feel to
the skin may indicate hypernatremia

19. INVESTIGATIONS
 Random blood sugar – Will most likely be low
 Hemogram – neutrophilia vs lymphocytosis;
Hemoglobin levels and hematocrit may be low
 Serum electrolytes – monitor potassium levels
Clinically significant electrolyte abnormalities are rare
in children with moderate dehydration. Any child
being treated with intravenous fluids for severe
dehydration, however, should have baseline
electrolytes, bicarbonate, and urea/creatinine values
tested.
Any child with evidence of systemic infection should
have a complete workup, including CBC count and
blood cultures. If indicated, urine cultures, chest
radiography, and/or lumbar puncture should be
performed.

20. IMAGING
 Abdominal films are not indicated
in the management of acute
gastroenteritis. If the clinician
suspects a diagnosis other than
acute gastroenteritis based on
history and physical examination
findings, appropriate imaging
modalities should be pursued.

21. TREATMENT
 PLAN A:
10mls/Kg of
ORS per
loose stool

24. ZINC SULPHATE
Dose
P.O Zinc sulphate 10mg OD x 2/52 – For <6months
P.O Zinc sulphate 20mg OD x 2/52 – For ≥6 months
Role
 Reduces fluid and salt loss in stool by improving
mucosal permeability
 Accelerated regeneration of mucosa
 Increases levels of brush-border enzymes
 Enhanced cellular immunity
 Higher levels of secretory antibodies
 Improves absorption of ORS

25. ROLE OF DRUGS
 Drugs are rarely needed. They deal with the
symptoms rather than causes of disease and
may distract from the use of appropriate fluid
therapy.
 Antibiotics are not indicated in viral or
uncomplicated bacterial gastroenteritis and may
cause harm.
a) In non-typhoid Salmonella infections antibiotics
increase the risk of prolonged carriage and
disease relapse.
b) Treating gastroenteritis due to Shiga toxin
producing E coli with antibiotics may increase
the risk of haemolytic uraemic syndrome.

26.  Antibiotics are required, however, for bacterial
gastroenteritis complicated by septicaemia and in
cholera, shigellosis, amoebiasis, giardiasis, and
enteric fever.
 Antidiarrhoeal and antiemetic agents are not
recommended for routine use because of the risk of
adverse effect.
a) Ondansetron does not have extrapyramidal effects
and reduces the duration and frequency of
vomiting, but also increases diarrhea
b) Loperamide decreases the duration of diarrhea, but
has potential severe adverse effects and evidence
that benefits outweigh potential harms is lacking

27. PREVENTION: HAND WASHING

29. PREVENTION

30. SUMMARY
 Rotavirus is the most common cause of acute
gastroenteritis worldwide and vaccination will
have a major impact on disease rates, morbidity,
and mortality
 Most children are not dehydrated and can be
managed at home
 Dehydration, metabolic acidosis, and electrolyte
disturbance can be prevented and treated by
fluid therapy
 Most children with mild-moderate dehydration
can be treated with oral or enteral rehydration
using low osmolality oral rehydration solutions

31.  Severely dehydrated or shocked children
usually need intravenous fluids and
hospital admission
 Drugs are usually unnecessary and may
do harm
 General practitioners have an important
role in prevention, through encouraging
breastfeeding, recommending and
advocating free access to rotavirus
vaccination, and educating carers about
personal and food hygiene

32. Unanswered research questions in acute
gastroenteritis
 How safe and effective is home based care for
children with mild-moderate dehydration?
 What role do food based oral rehydration solutions
have in developed communities?
 What is the role and safety of new generation
antiemetics and antidiarrhoeal agents?
 What is the role of zinc supplementation in well
nourished children?
 Do probiotics have a role as adjuvant therapy, and
what type, dose, and regimen is optimal?

33. REFERENCES
 Singh, Amandeep (July 2010). "Pediatric Emergency
Medicine Practice Acute Gastroenteritis — An
Update". Pediatric Emergency Medicine Practice. 7
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Coppola, RC (October 2011). "Epidemiology and
prevention of rotavirus infection: an underestimated
issue?". Journal of Maternal-Fetal and Neonatal
Medicine. 24 (Suppl 2): 48–
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34. THANK YOU!
QUESTIONS?