Dysentery
Dr. Raheel Ahmed
FCPS Pediatric Medicine
Children Hospital, Chandka Medical College, Larkana
On a global scale, of the estimated 165 million Shigella diarrhoeal episodes estimated to occur each year, 99% occur in developing countries, mainly in children.
1999, reported Shigella to be responsible for 1.1 million deaths per year, 61% of which in children less than 5 years of age
In 2013, estimates suggesting between 28,000 and 48,000 deaths annually amongst children under 5 years due to Shigellosis
Dysentry occurs predominantly in developing countries due to overcrowding and poor sanitation.
Infants,
non-breast fed children,
children recovering from measles,
malnourished children, and
adults older than 50 years
have a more severe illness and a greater risk of death.
Bascillary Dysentery
Shigella is a Gram-negative, non-motile bacillus belonging to the Enterobacteriaceae family.
There are four species of Shigellae:
S. dysenteriae, S. flexneri, S. boydii and S. sonnei
(designated as serogroups A, B, C and D respectively).
S. boydii and S. sonnei usually cause a relatively mild illness (watery or bloody diarrhoea only),
S. flexneri and S. dysenteriae are chiefly responsible for endemic and epidemic shigellosis (respectively) in developing countries, with high transmission rates and significant case fatality rates.
Transmission occurs via the faecal-oral route, person-to-person contact, household flies, infected water, and inanimate objects.
Shigella species can survive in gastric acid, and infection can occur following exposure to as few as 10-100 organisms.
Once infected, all Shigella species multiply invading the colonic epithelium where pro-inflammatory cytokines are released, and the subsequent inflammatory reaction destroys the epithelial cells lining the gut mucosa, allowing for further direct invasion by Shigella.
The resultant infectious diarrhoea is associated with loss of water and electrolytes and a clinical picture of abdominal cramping, fever, and bloody/mucoid stools.
History
Examination
Investigation
Case Definitions
Suspected case: a case with gastroenteritis, bloody mucoid diarrhea, abdominal cramps, fever and rectal pain.
Probable case: A clinical compatible case thatis epidermiologically linked i.e. Is a contact toa confirmed case or a member of risk group defined by public health authorities during an outbreak.
Confirmed case: a case that meets the confirmed laboratory criteria for diagnosis i.e. ISOLATION of Shigella species from a clinical specimen.
Period of Communicability: shed in feces 4 weeks after infection then as long as organisms present in faeces.
3. • On a global scale, of the estimated 165 million Shigella diarrhoeal
episodes estimated to occur each year, 99% occur in developing
countries, mainly in children.
• 1999, reported Shigella to be responsible for 1.1 million deaths
per year, 61% of which in children less than 5 years of age
• In 2013, estimates suggesting between 28,000 and 48,000
deaths annually amongst children under 5 years due to
Shigellosis
4.
5.
6. • Dysentry occurs predominantly in developing countries due to
overcrowding and poor sanitation.
• Infants,
• non-breast fed children,
• children recovering from measles,
• malnourished children, and
• adults older than 50 years
have a more severe illness and a greater risk of death.
7.
8.
9.
10.
11.
12. Bascillary Dysentery
• Shigella is a Gram-negative, non-motile bacillus belonging to the
Enterobacteriaceae family.
• There are four species of Shigellae:
S. dysenteriae, S. flexneri, S. boydii and S. sonnei
(designated as serogroups A, B, C and D respectively).
• S. boydii and S. sonnei usually cause a relatively mild illness
(watery or bloody diarrhoea only),
• S. flexneri and S. dysenteriae are chiefly responsible for endemic
and epidemic shigellosis (respectively) in developing countries,
with high transmission rates and significant case fatality rates.
13. • Transmission occurs via the faecal-oral route, person-to-person contact,
household flies, infected water, and inanimate objects.
• Shigella species can survive in gastric acid, and infection can occur
following exposure to as few as 10-100 organisms.
• Once infected, all Shigella species multiply invading the colonic
epithelium where pro-inflammatory cytokines are released, and the
subsequent inflammatory reaction destroys the epithelial cells lining the
gut mucosa, allowing for further direct invasion by Shigella.
• The resultant infectious diarrhoea is associated with loss of water and
electrolytes and a clinical picture of abdominal cramping, fever, and
bloody/mucoid stools.
19. Examination
• Vitals HR and BP (postural changes)
• A high fever (39°C) -Shigella infection, the absence of fever is typical
of E coli O157:H7 infections.
• Signs of dehydration
• detect abdominal tenderness and abdominal masses.
• Finding a mass in the abdomen, particularly on the right side, in a
child raises the possibility of an intussusception
• A digital rectal examination in a child with acute bloody diarrhea is
unlikely to provide actionable information
20. Investigation
• Stool dr for occult blood, lukocytes, microscopy
• Stool culture
• PCR
• CBC
• S. ELECTROLYTE
• S. CREATININE
• BLOOD CULTURE
• URINE CULTURE
21. Case Definitions
• Suspected case: a case with gastroenteritis, bloody mucoid diarrhea,
abdominal cramps, fever and rectal pain.
• Probable case: A clinical compatible case thatis epidermiologically
linked i.e. Is a contact toa confirmed case or a member of risk group
defined by public health authorities during an outbreak.
• Confirmed case: a case that meets the confirmed laboratory criteria
for diagnosis i.e. ISOLATION of Shigella species from a clinical
specimen.
• Period of Communicability: shed in feces 4 weeks after infection then
as long as organisms present in faeces.
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27. complications
• Complications due to Shigellosis include
• sepsis,
• rectal prolapse,
• arthralgia,
• intestinal perforation,
• toxic megacolon,
• electrolyte imbalance,
• seizures, and
• leukaemoid reactions
