Download In diarrhoea

Diarrhea
What is Diarrhoea?
Diarrhoea is a symptom characterized by
an abnormal increase in stool frequency
(more than 3 times daily) or liquidity (>
80% water);
The normal frequency of bowel
movements varies with each individual
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DEFINITIONS – IDSA & WGO
“Diarrhea” is an alteration in a normal bowel movement characterized by an increase in
the water content, volume, or frequency of stools.
In adults, a decrease in consistency (i.e., soft or liquid) and an increase in frequency of bowel
movements to >3 stools per day (24 hrs) have often been used as a definition for epidemiological
investigations.
Diarrhea is defined as daily stools with a mass greater than 15 g/kg for children younger than 2
years and greater than 200 g for children aged 2 years and older.
“Infectious diarrhea” is diarrhea due to an infectious etiology, often accompanied by
symptoms of nausea, vomiting, or abdominal cramps. Dysentery describes an infectious
diarrhea with visible blood and mucus in the stool.
“Acute diarrhea” is an episode of diarrhea of <14 days in duration.
“Persistent diarrhea” is diarrhea of 14 or more days in duration.
Some experts refer to diarrhea that lasts 30 days or more as “chronic.”
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Causes:
bacterial or viral infection through
ingestion of contaminated food or drink;
1. E.Coli, S.aureus  toxins  mucosal
cells hypersecretion of fluid watery
diarrhoea with little or no fever or other
symptoms;
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Causes:
2. Invasive E. coli, salmonella and shigella:
directly invade mucosal epithelial cells
and cause an inflammatory reaction
less fluid diarrhoea accompanied by
nausea, vomiting, cramps and
sometimes low-grade fever
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Causes:
3. Viral infections, which often affect babies and
young children, also produce watery diarrhoea
4. Non-infective causes: stress, alcohol, and hot
spicy food
5. Drugs: antibiotics “all but varying degrees”.
Depends on extent that drug disrupts normal
intestinal microflora. Other: laxatives, misoprostol.
Olsalazine, anticancer, antihypertensive agents,
parasympathomimitic drugs, digoxin, quinidine,
magnesium hydroxide, laxatives.
6. Chronic diarrhea. Lasts more than 4 weeks.
Protozoal infections, food, IBS, hyperthyroidism.
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Infectious diarrhea
Infectious diarrhea is further
inflammatory diarrhea.
classified
into
non-inflammatory
and
Non-inflammatory diarrheas
Inflammatory diarrheas
Generally a less severe illness
Generally a more severe illness
Patients present with nonbloody, watery
stools; patients are afebrile and without
significant abdominal pain.
Patients present with bloody diarrhea, severe
abdominal pain, and fever.
Examination of stool specimens does not
reveal the presence of fecal white blood cells
(WBC) or occult blood.
Examination of stool specimens reveals the
presence of large numbers of fecal
leukocytes.
Typically caused by rotaviruses, noroviruses,
Staphylococcus aureus, Bacillus cereus,
Clostridium perfringens, Cryptosporidium
parvum, and Giardia lamblia.
Caused by invasive pathogens including
Campylobacter jejuni, Shigella species,
Salmonella species, Clostridium difficile,
Shiga toxin-producing Escherichia coli
(STEC), and Entamoeba histolytica.
Most patients require only supportive
therapies
Selected persons may benefit from
antimicrobial therapy directed at the
causative pathogen.
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Consequences
Normal faeces contain 60-85 % water
Water loss during defecation= 70-200
mL/day
In diarrhoea: water loss 4X normal K
and Na loss fall in plasma pH (acidosis)
serious metabolic consequences
Fluid & electrolyte losses are increased if
vomiting also occurs
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Consequences
In babies/children: hazardous as high
proportion of total body weight is lost and
dehydration can occur very rapidly
Elderly are also particularly sensitive to
the effects of fluid and electrolytes loss,
especially if on diuretics
Reduction in blood volume + RAS  +
aldosterone (1) loss of K (hypokalemia)
(2) Excessive fluid loss reduction of
renal artery flow renal failure
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Patient Evaluation: All of the following must
be considered before selecting the most
appropriate management.
Age
Onset and duration or diarrhea
Description of stool
Other symptoms
Medications
Recent travel
Medical history.
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When to refer to a physician
 Very young or very old.
 Bloody stool.
 High fever (greater than 38.5 ˚C).
 Dehydration or weight loss greater than 5 % of total body
weight. Signs of dehydration: dry mouth, sunken eyes,
crying without tears, dry skin that is less elastic than
normal skin.
 Severe vomiting..
 Duration: (see next slide)
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When to Refer?
If diarrhoea lasts more than:
72 hours : adults and older children
48 hours : children < 3 years old & elderly
24 hours in children < 1 year old
Refer Immediately in infants under 3
months old
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Treatment of children based on the degree of
dehydration
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Treatment
Oral rehydration therapy (ORT)
Opioids
Adsorpants
Dietary management
In UK: belladonna extract
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Oral rehydration therapy (ORT)
First line treatment of acute diarrhoea
the very young & elderly (particularly
important)
ORT not intended to relieve symptoms
Use of antidiarrheals (antimotility drugs or
adorbants) is regarded unnecessary and
sometimes undesirable
Use of antidiarrheals (for
comfort/convenience) is used as adjunct to
ORT
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Oral rehydration therapy (ORT)
Mode of action:
replace water and electrolytes lost
through diarrhoea and vomiting;
K & Na: replace ions
citrate and/or bicarbonate: correct
acidosis
glucose: carrier for Na ions and hence
water across the mucosa of the small
intestine
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Oral rehydration therapy (ORT)
ORT is not intended to stop diarrhoea, but
acute diarrhoea is self-limiting and
normally ceases within 24-48 hours;
ORT can be recommended for patients of
any age, even when referral to a doctor is
considered necessary
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ORT is not intended to stop diarrhea, but acute diarrhea is
self-limiting and normally ceases within 24–48 hours. ORT can
be recommended for patients of any age, even when referral
to a doctor is considered necessary.
An oral rehydration product (Dioralyte Relief [Sanofi-Aventis])
containing powdered rice starch in place of glucose is claimed to
achieve even greater rehydration than glucose over time, and
the rice starch is claimed to help produce firmer stools, leading
to faster recovery compared with glucose.
A Cochrane Review found that polymer (including rice)-based
ORS showed some advantages compared with glucose-based
ORS for treating diarrhea of any cause.
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Dose & Administration of ORS
the content of 1 sachet or 2 effervescent
tablets should be dissolved in 200-250 ml
of water (freshly bolied and cooled in case
of infants)
discard unused solution 1 hr after
reconstitution or no longer than 24 hrs (if
refrigerated)
Dose, adults: 200-400 ml after every
loose motion, or 2-4 L over 4-6 hrs
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Dose & Administration of ORS
Patients may prefer to sip 1-2 tsp every few
minutes rather than drink large quantities less
frequently
children > 2 yrs: cupful (200ml) after every
loose stool
children < 2 yrs: ¼- ½ cupful
Infants: 1-1.5 normal feed volume
Both breast and bottle-fed babies should
continue to be fed normally (without dilution)
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Contraindications & cautions
No contraindications to ORS unless
the patient is vomiting frequently  IV
fluid and electrolyte replacement;
fluid overload from excessive
administration of ORS is highly unlikely
unless continued for babies and young
children > 48 hrs (recognised by puffy
eyelids)  rapidly withhold ORS and
other liquids
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Opioids
Loperamide, Morphine, Codeine
Mode of action:
1. increase tone of both small and large
bowel and reduce intestinal motility
(enhances fluid and electrolyte reabsorption);
2. increase the sphincter tone and
decrease secretory activity along GIT
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Loperamide
It is a synthetic opioid agonist that has a
high affinity for, and exerts a direct action
on  opiate receptors in the gut wall;
also has a high first-pass metabolism so
very little reaches the systemic circulation;
effective in reducing the duration of
diarrhea (25 vs 40 hrs with placebo)
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Loperamide
50 fold more potent than morphine and 23 times more potent than diphenoxylate in
its effect on GI motility, but penetrates the
CNS poorly, thus has lower risk of CNS
side effects;
Other mechanisms: disruption of
cholinergic and non-cholinergic
mechanisms of peristalsis, inhibition of
calmodulin function and inhibition of
voltage dependent Ca channels
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Loperamide
Indications:
traveller’s diarrhoea
non-specific acute diarrhoea
chronic diarrhoea associated with inflammatory
bowel disease
AAP does not recommend use in children < 6
years old
Used when patient is afebrile or have mild fever
and does not have bloody stool
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Loperamide
Dosage & Administration
dosage forms: caplets (2 mg), and liquid
(1 mg/5ml)
Dose: 4 mg initially, then 2 mg after each
loose stool/ Do not exceed 16 mg/day
Consult product instructions for
pediatric dose
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Loperamide
Contraindication
Loperamide should not be used in
patients with fecal leukocytes, high fever,
or blood or mucus in the stool (dysentery);
Loperamide may cause paralytic ileus in
patients with desentery
Paralytic ileus: paralysis or inactivity of the intestine that prohibits the
passage of material within the intestine. May be a result of anticholinergic
drugs, injury or surgery
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Adsorbents
Kaolin, pectin, attapulgite and bismuth
subsalicylate;
Kaolin: a natural hydrated aluminum silicate.
Not absorbed from GIT, 90% metabolized in gut
and excreted in faeces
Attapulgite is another naturally occur clay
mineral, consisting of hydrous Mg-Al-silicate;
kaolin & attapulgite have varying and relatively
weak adsorptive properties in respect to
diarrhoea producing bacteria
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Adsorbents
Mode of action:
1.
adsorb the microbial toxins and microorganisms to their own surfaces
drugs not absorbed from the GIT toxins and
MOs are excreted in stool;
2. Hydrophilic adsorbents (e.g. pectin and bulkforming agents; ispaguala, methylcellulose, and sterculia),
bind water within the intestine causing watery
stool to become more formed
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Adsorbents
the main constituents in the antidiarrhoeal
preparations for young children (whom
opiates and antimuscarinics are
contraindicated);
not absorbed from GIT harmless and
safe to use
Debate: reduce evacuation of faecesprolong presence of pathogens/toxins in
bowel. Adsorption: non-specific process
(medicines)
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Dietary Management
Traditionally: withdrawal of feedings,
initiation of clear liquids, with a slow
reintroduction of feedings in 24 hrs
However, oral intake does not worsen
diarrhoea, clinically significant nutrient
malabsorption is uncommon (80-95% CHO, 70%
of fat and 75% of the nitrogen from protein) in acute
diarrhoea and bowel rest is generally not
necessary
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What foods are best for
refeeding?
most infants and children with diarheoa
can tolerate full-strength breats milk and
cow’s milk;
The familiar BRAT (bananas, rice, apple
sauce and toast) is frequently prescribed insufficient calories, protein and fat
especially in strict or prolonged use and is
not recommended by AAP
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What foods are best for
refeeding?
Diet should include:
complex carbohydrate-rich foods (e.g.
rice, potatoes, bread, cereals)
Yogurt
lean meats
Fruits and vegetables
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What foods are best for
refeeding?
Avoid:
fatty foods
foods rich in simple sugars that may
cause osmotic diarrhoea
spicy foods that may cause GI upset
Caffeine (WHY??)
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PROBIOTICS: AN
UPDATE
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Background
Probiotics are live organisms that are
ingested to provide therapeutic or
preventative benefit for the host. The most
commonly used are the lactic acidproducing bacteria bifidobacteria and
lactobacilli. Probiotics also include the
yeast Saccharomyces boulardii. Probiotics
are commonly promoted to strengthen the
immune defenses.
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Bifidobacteria spp
Saccharomyces
boulardii
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Probiotics, Beneficial
Microbes
Beneficial microbes
such as bifidobacteria
live in the intestinal ecosystem with potentially
pathogenic bacteria. Beneficial microbes
prevent the overgrowth of “bad bacteria” by
producing antimicrobial agents. Additionally,
beneficial
microbes
competitively
limit
pathogenic bacterial overgrowth by occupying
receptor sites and vying for space and
nutrients. Beneficial microbes may also
increase intestinal production of mucin, which
stimulates the production of mucus, forming a
protective barrier on the intestinal lining
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In order to be effective, probiotics must be
able to withstand a wide range of pH
variation. Many microbes cannot withstand
the protective acid barrier of the stomach
and the effects of bile. An effective
probiotic also must be able to colonize the
gut and be able to attach to the intestinal
epithelium. Additionally, the probiotic
should not disturb healthy intestinal
microbes
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Probiotic Bacteria and Yeasts
Bifidobacteria are anaerobic, rod-shaped,
gram-positive bacteria. Bifidobacteria are
the most prominent beneficial microbes in
the
colon.
Bifidobacteria
produce
antimicrobial substances that have a
broad spectrum of antimicrobial activity
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Bifidobacteria that are commonly used
as probiotics include Bifidobacterium
longum, B. breve, B. infantis, B. bifidum, B.
lactis, and B. adolescentis. Bifidobacteria
supplements are most commonly combined
with other probiotics.
Lactobacilli are a group of gram-positive
rods that are obligate and facultative
anaerobes.
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Other bacteria sometimes used as
probiotics
include
Streptococcus
thermophilus and Leuconostoc species.
The yeasts Saccharomyces boulardii and
S. cerevisiae are also used
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Probiotics for Diarrhea
Probiotics may be useful as adjunctive treatment
of adults and children with infectious diarrhea.
Several species of Lactobacillus seem to reduce
the duration of diarrhea, particularly in rotaviral
infections. For antibiotic-associated diarrhea,
Lactobacillus rhamnosus GG, S. boulardii, and
probiotic mixtures appear to be effective
prophylactic agents. Given along with antibiotics,
these probiotics can reduce the incidence of
diarrhea by about 60% to 65%. The effectiveness
of probiotics on treatment of antibiotic-associated
diarrhea is less clear.
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SAFETY
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SUMMARY
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