Infectious Diarrhea by Dr Arun Aggarwal Gastroenterologist

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Infectious Diarrhea

• Dr. Arun Aggarwal Gastroenterologist

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Etiology

• Diarrhea noninflammatory and inflammatory.
• Enteropathogens elicit noninflammatory diarrhea
  through enterotoxin production by some bacteria,
  destruction of villus (surface) cells by viruses,
  adherence by parasites, and adherence and/or
  translocation by bacteria.
• Inflammatory diarrhea caused by bacteria that
  invade the intestine directly or produce
  cytotoxins.

By Dr Arun Aggarwal Gastroenterologist
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Causative Agents of Gastroenteritis

• BACTERIA   
• Aeromonas
• Bacillus cereus   
• Campylobacter jejuni   
• Clostridium perfringens   
• Clostridium difficile   
• Escherichia coli   
• Plesiomonas
• shigelloides   
• Salmonella   
• Shigella   
• Staphylococcus aureus   
• Vibrio cholerae 01 and 0139   
• Vibrio parahaemolyticus   
• Yersinia enterocolitica

• VIRUSES
• Astroviruses  
• Caliciviruses  
• Norovirus   
• Enteric adenoviruses 
• Rotavirus  
• Cytomegalovirus   
• Herpes simplex viruses

•  Balantidium coli   
• Blastocystis hominis   
• Cryptosporidium parvum   
• Cyclospora cayetanensis   
• Encephalitozoon intestinalis   
• Entamoeba histolytica   
• Enterocytozoon b bieneusi   
• Giardia lamblia   
• Isospora belli   
• Strongyloides stercoralis   
• Trichuris trichiura

PARASITES
By Dr Arun Aggarwal Gastroenterologist
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• Chronic or persistent diarrhea lasting 14 days or
  more may be due to
• an infectious agent such as Giardia lamblia,
  Cryptosporidium parvum, and enteroaggregative or
  enteropathogenic E. coli
• any enteropathogen that infects an
  immunocompromised host
• residual symptoms due to damage to the intestine
  by an enteropathogen after an acute infection.

By Dr Arun Aggarwal Gastroenterologist
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Indications for stool examination for O P

• Pt have a history of recent travel to an endemic
  area, stool cultures are negative for other
  enteropathogens, and diarrhea persists for more
  than 1 wk
• part of an outbreak of diarrhea
• immunocompromised.

By Dr Arun Aggarwal Gastroenterologist
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Epidemiology
Agent
Salmonella Poultry, egg, peanut butter, reptiles
Campylobacter Raw poultry
E. Coli Beef, spinach, milk
Yersinia Pork, iron overload (thallasemia)
V. Cholerae Iron overload ( thallassemia)
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Factors that increase susceptibility to infection
with enteropathogens include

• Young age
• Immune deficiency
• Measles
• Malnutrition
• Travel to an endemic area
• Lack of breast-feeding
• Exposure to unsanitary conditions
• Ingestion of contaminated food or water
• Level of maternal education
• Attendance at a childcare center.

By Dr Arun Aggarwal Gastroenterologist
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Immune-Mediated Extraintestinal Manifestations of
Enteric Pathogens
Manifestation Related Enteric Pathogen(s)
Reactive arthritis Salmonella, Shigella, Yersinia, Campylobacter, Cryptosporidium, Clostridium difficile
Guillain-Barré syndrome Campylobacter
Glomerulonephritis Shigella, Campylobacter, Yersinia
IgA nephropathy Campylobacter
Erythema nodosum Yersinia, Campylobacter, Salmonella
Hemolytic anemia Campylobacter, Yersinia
HUS S. dysenteriae , E. coli
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Specific Pathogens
By Dr Arun Aggarwal Gastroenterologist
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Cholera

• Gram negative, slightly curved rod.
• V. cholera O1 and O139 are responsible for
  causing disease.
• The two biogroups (or biotypes) of V. cholerae O1
  are differentiated as classic and El Tor
• V. cholerae O1 has two major O antigenic types
  (Ogawa and Inaba) and an unstable intermediate
  type (Hikojima).
• V. cholerae O139 is closely related to the El Tor
  biotype

By Dr Arun Aggarwal Gastroenterologist
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Epidemiology

• Transmission is usually by fecal-oral spread with
  contaminated water.
• Humans are the only known reservoirs of V.
  cholerae.
• Colonization usually requires the ingestion of a
  large number of viable vibrios (gt108 viable
  units), in part, because the organisms are killed
  by acid environments including the normal
  stomach.
• The primary mechanism of fluid loss is activation
  of adenylyl cyclase at the cytoplasmic surface of
  the basolateral membrane by the enterotoxin,
  cholera toxin.

By Dr Arun Aggarwal Gastroenterologist
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Clinical Features

• Profuse, painless, watery diarrhea with a
  rice-water consistency and a fishy odor,
  sometimes with flecks of mucus but no blood.
• Fecal leukocytes are not present because V.
  cholera does not invade the mucosa.
• Diagnosis is primarily clinical.
• The gold standard for cholera diagnosis remains
  stool culture on TCBS medium.

By Dr Arun Aggarwal Gastroenterologist
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Treatment

• Rehydration is the most important treatment.
• Antibiotics are useful in shortening the duration
  of illness, reducing the period of excretion of
  the organisms, and decreasing the requirements
  for fluid replacement.
• Doxycycline is drug of choice, Bactrim can be
  used for lt8 yrs, quinolones are effective.

By Dr Arun Aggarwal Gastroenterologist
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Complications

• Lethargy, seizures, altered consciousness, fever,
  hypoglycemia, hyperglycemia, and death.
• Inadequate fluid and electrolyte replacement may
  lead to acute tubular necrosis.
• Hypokalemic arrhythmia can cause sudden death.
• Children with low potassium levels can develop
  paralytic ileus and abdominal distention that can
  make oral rehydration impossible.
• Pulmonary edema occurs in some children, probably
  because of fluid overload during rehydration.

By Dr Arun Aggarwal Gastroenterologist
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Vaccine

• Phenol-killed organisms administered parenterally
  as a two-dose primary series followed by boosters
  every 6 mo to maintain immunity.
• Vaccine has about 50 efficacy by 36 mo after
  vaccination, does not protect against O139
  vibrios, and is highly reactogenic (i.e., pain,
  erythema, local induration, fever, headaches).
• Vaccine should be used only in very high-risk
  persons (e.g., those with achlorhydria) with a
  very high probability of exposure.
• It is not recommended for children lt6 mo of age.

By Dr Arun Aggarwal Gastroenterologist
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Salmonella
By Dr Arun Aggarwal Gastroenterologist
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• Gram negative rod, dont ferment lactose, grow
  aerobically.
• Poultry and poultry products (mainly eggs) cause
  about half of the common-source outbreaks.
• Meats, especially beef and pork, cause about 13
  of the outbreaks, and raw or powdered milk and
  dairy products are the source of about 5 of the
  outbreaks.
• The estimated number of bacteria that must be
  ingested to cause disease is 106108 organisms.
• Ingested Salmonella organisms reach the stomach,
  where acid is the first protective barrier.
• Achlorhydria, buffering medications, rapid
  gastric emptying after gastrectomy or
  gastroenterostomy, and a large inoculum enable
  viable organisms to reach the small intestine.

By Dr Arun Aggarwal Gastroenterologist
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• In the small and large intestines, salmonellae
  have to compete with normal bacterial flora to
  multiply and cause disease prior antibiotic
  therapy disrupts this competitive relationship.
• After multiplication within the lumen, the
  organisms penetrate through the Peyer patches,
  typically at the distal part of the ileum and the
  proximal part of the colon.
• Children with sickle cell disease are prone to
  Salmonella septicemia and osteomyelitis.

By Dr Arun Aggarwal Gastroenterologist
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Clinical manifestations

• The most common clinical presentation is acute
  enteritis.
• After an incubation period of 672?hr (mean,
  24?hr), there is an abrupt onset of nausea,
  vomiting, and crampy abdominal pain primarily in
  the periumbilical area and right lower quadrant,
  followed by mild to severe watery diarrhea and
  sometimes by diarrhea containing blood and mucus.
  
• Fever (temperature of 101102F 38.539C).
• The stool typically contains a moderate number of
  polymorphonuclear leukocytes and occult blood.
• Symptoms subside within 27 days in healthy
  children.

By Dr Arun Aggarwal Gastroenterologist
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Conditions That Increase the Risk of Salmonella
Bacteremia During Salmonella Gastroenteritis

• Neonates and young infants (3 mo of age)
• AIDS, chronic granulomatous disease, and other
  immuno deficiencies
• Malignancies, especially leukemia and lymphoma
• Immunosuppressive and corticosteroid therapy
• Hemolytic anemia, including sickle cell disease,
  malaria, and bartonellosis
• Collagen vascular disease
• Inflammatory bowel disease
• Gastrectomy or gastroenterostomy
• Achlorhydria or antacid medication use
• Impaired intestinal motility
• Schistosomiasis
• Malnutrition

By Dr Arun Aggarwal Gastroenterologist
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• Diagnosis stool culture, rectal swab, latex
  agglutination, serological assays
• Treatment correction of dehydration and
  electrolyte disturbances.
• Antibiotics ampicillin, bactrim, cefotaxime,
  ceftriaxone, quinolones

By Dr Arun Aggarwal Gastroenterologist
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• In patients with gastroenteritis, antimicrobial
  agents do not shorten the clinical course, nor do
  they eliminate fecal excretion of Salmonella.
• By suppressing normal intestinal flora,
  antimicrobial agents may prolong the excretion of
  Salmonella and increase the risk of creating the
  chronic carrier state.
• Antibiotics therefore are not indicated routinely
  in treating Salmonella gastroenteritis.
• They should be used in infants (3 mo of age) and
  other children who are at increased risk of a
  disseminated disease . (previous table)

By Dr Arun Aggarwal Gastroenterologist
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Shigella
By Dr Arun Aggarwal Gastroenterologist
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• Four species of Shigella are responsible for
  shigellosis S. dysenteriae (serogroup A), S.
  flexneri (serogroup B), S. boydii (serogroup C),
  and S. sonnei (serogroup D).
• Contaminated food (often a salad or other item
  requiring extensive handling of the ingredients)
  and water are important vectors.
• Person-to-person transmission is probably the
  major mechanism of infection.
• Shigellae require very low inocula to cause
  illness. Ingestion of as few as 10 S. dysenteriae
  serotype 1 organisms can cause dysentery.

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• The basic virulence trait shared by all shigellae
  is the ability to invade intestine.
• The pathologic changes of shigellosis take place
  primarily in the colon.
• Secretory IgA and serum antibodies develop within
  days to weeks after infection with Shigella.
  (protection is serotype specific).

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• Incubation period 12?hr to several days.
• Severe abdominal pain, high fever, emesis,
  anorexia, generalized toxicity, urgency, and
  painful defecation characteristically occur.
• Physical examination may show abdominal
  distention and tenderness, hyperactive bowel
  sounds, and a tender rectum on digital
  examination.
• The diarrhea may be watery and of large volume
  initially, evolving into frequent small-volume,
  bloody mucoid stools.

By Dr Arun Aggarwal Gastroenterologist
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• Neurologic findings occur in as many as 40 of
  hospitalized infected children.
• Convulsions, headache, lethargy, confusion,
  nuchal rigidity, or hallucinations may be present
  before or after the onset of diarrhea.
• The most common complication of shigellosis is
  dehydration.
• S. dysenteriae serotype 1 infection is commonly
  complicated by hemolytic-uremic syndrome.
• This syndrome is caused by Shiga toxinmediated
  endothelial injury.

By Dr Arun Aggarwal Gastroenterologist
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• Diagnosis clinical picture, stool examination,
  rectal swab, blood cultures
• Treatment fluid and electrolytes
• Antibiotics azithromycin, ampicillin, bactrim,
  cefixime, nalidixic acid, quinolones.

By Dr Arun Aggarwal Gastroenterologist
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E. coli
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ETEC EIEC EPEC STEC/ EHEC EAggEC
Population at risk gt1 Yr travellers gt1 yr lt2 yr 6mo- 10 yr lt1 yr travellers
Watery diarrhea
Bloody diarrhea --- --- (HUS) ---
Duration Acute Acute Acute/ persistent Acute Acute/ persistent
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Camplylobacter
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• Human campylobacterioses most commonly result
  from ingestion of contaminated food or water,
  from direct contact with environmental sources
  (i.e., a pet), or from person-to-person
  transmission.

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• Patients may have loose, watery stools or bloody
  and mucus-containing stools (dysentery).
• Fever, vomiting, malaise, and myalgia are common.
• The abdominal pain is periumbilical.
• Abdominal pain may mimic appendicitis or
  intussusception.
• Persistent infection may mimic chronic IBD.

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• Diagnosis stool culture, rectal swab,
  serological studies.
• The optimum incubation temperature for C. jejuni
  and C. coli is 42 to 43ºC as a result, the term
  "thermophilic" campylobacters is sometimes
  applied to these species.
• Treatment
• Fluid replacement
• Correction of electrolytes
• Antibiotics azithromycin, aminoglycosides,
  doxycycline, trimethoprim
• Antibiotics are recommended for patients with the
  dysenteric form of the disease, high fever, or a
  severe course and for children who are
  immunosuppressed or have underlying diseases.

By Dr Arun Aggarwal Gastroenterologist
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Yersinia
By Dr Arun Aggarwal Gastroenterologist
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• Y. enterocolitica is transmitted to humans
  through food, water, animal contact, and
  contaminated blood products.
• The organisms most often enter by the alimentary
  tract and cause mucosal ulcerations in the ileum.
  Necrotic lesions of Peyer patches and mesenteric
  lymphadenitis occur.
• Presentation enterocolitis with diarrhea, fever,
  and abdominal pain.
• Acute enteritis is more common among younger
  children, and mesenteric lymphadenitis that may
  mimic appendicitis.

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• Diagnosis stool culture, rectal swab.
• Treatment self-limiting disease and no benefit
  of antibiotic therapy is established.
• Patients with systemic infection and very young
  children in whom septicemia is common should be
  treated.
• Yersinia strains are sensitive to
  trimethoprim-sulfamethoxazole, aminoglycosides,
  third-generation cephalosporins, and quinolones.

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• Patients on deferoxamine should discontinue iron
  chelation therapy during treatment for Y.
  enterocolitica, especially if they have
  complicated gastrointestinal infection or
  extraintestinal infection.

By Dr Arun Aggarwal Gastroenterologist
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C. difficile
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• C difficileassociated diarrhea, also known as
  pseudomembranous colitis or antibiotic-associated
  diarrhea, is a major cause of nosocomial
  diarrhea.
• C. difficile is a ubiquitous spore-forming
  gram-positive anaerobic bacillus.
• The organism produces two toxins toxin A
  (enterotoxin) acts on the intestinal mucosa to
  produce diarrhea toxin B (cytotoxin) increases
  vascular permeability in low doses and is lethal
  to experimental animals in high doses.

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• Virtually all known antibiotics have been
  implicated penicillins, broad-spectrum
  cephalosporins, and clindamycin are the most
  frequent offenders.
• Newborns are often colonized with C. difficile
  during the first weeks of life. Carriage
  decreases to the adult rate of 13 by 2 yr of
  age.
• Illness is unusual in neonates and infants the
  basis for this remains unknown.

By Dr Arun Aggarwal Gastroenterologist
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• The classic picture of pseudomembranous colitis
  is diarrhea with blood and mucus accompanied by
  fever, cramps, abdominal pain, nausea, and
  vomiting. Disease occurs during and as long as
  weeks after antibiotic therapy.
• The diagnosis is confirmed by detecting C.
  difficile or its toxin in the stool.
• Findings at sigmoidoscopy or colonoscopy include
  pseudomembranous nodules and plaques
  characteristic of toxin-related colitis. Fecal
  leukocytes are present in approximately one half
  of cases occult or frank blood is common.

By Dr Arun Aggarwal Gastroenterologist
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• The first and essential step in treatment is the
  discontinuation of the current antibiotics, if
  possible.
• If symptoms persist, antibiotics cannot be
  discontinued, or the illness is severe, then oral
  metronidazole (2040?mg/kg/24?hr divided q 68?hr
  PO) or vancomycin (2540?mg/kg/24?hr divided q
  6?hr PO) should be given for a 710 day course.

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• The initial response rate is gt95, but 530 of
  patients have clinical relapse, usually within
  12 wk of treatment.
• These patients should be re-evaluated and treated
  again most will respond to a second course of
  the original treatment.
• A few patients develop multiple recurrences, with
  short-lived responses to repeated treatment.
• Treatment strategies for these patients include
  oral cholestyramine, oral bacitracin, oral
  immunoglobulin, reconstitution of bowel flora
  with oral lactobacilli or baker's yeast, or
  instillation of fecal flora by tube feeding or
  enemas (faeces transplant).

By Dr Arun Aggarwal Gastroenterologist
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Rota Virus
By Dr Arun Aggarwal Gastroenterologist
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• Rotavirus causes 3 million cases of diarrhea,
  50,000 hospitalizations, and 2040 deaths
  annually in the United States.
• Disease tends to be most severe in patients 3-24
  months of age.
• Infants younger than 3 mo of age are relatively
  protected by transplacental antibody and possibly
  breast-feeding.

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• The virus is shed in stool at very high
  concentration before and for days after the
  clinical illness.
• Very few infectious virions are needed to cause
  disease in a susceptible host.
• The gastric mucosa is not affected despite the
  commonly used term gastroenteritis.
• Selective viral infection of intestinal villus
  tip cells thus leads to
• an imbalance in the ratio of intestinal fluid
  absorption to secretion
• malabsorption of complex carbohydrates,
  particularly lactose.

By Dr Arun Aggarwal Gastroenterologist
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• Clinical manifestations incubation period lt48
  hrs
• mild to moderate fever and vomiting followed by
  the onset of frequent, watery stools.
• Diagnosis Enzyme immunoassays, which offer
  approximately 90 specificity and sensitivity,
  are available for detection of group A rotavirus
  and enteric adenovirus in stool samples.
• Laboratory findings Isotonic dehydration with
  acidosis.

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Treatment

• Avoiding and treating dehydration are the main
  goals in treatment of viral enteritis.
• A secondary goal is maintenance of the
  nutritional status of the patient.
• Controlled studies have shown no benefit from
  antiemetics or antidiarrheal drugs.
• Therapy with probiotic organisms such as
  Lactobacillus species has been shown to reduce
  somewhat the intensity and duration of illness.
• Vaccine

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Amebiasis
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• Infection is established by ingestion of parasite
  cysts.
• Cysts are resistant to environmental conditions
  such as low temperature and the concentrations of
  chlorine commonly used in water purification the
  parasite can be killed by heating to 55C.
• Infection is not transmitted by trophozoites
  because of their rapid degeneration outside the
  body or in the low pH environment of normal
  gastric contents.
• Food or drink contaminated with Entamoeba cysts
  and direct fecal-oral contact are the most common
  means of infection.

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• Once E. histolytica trophozoites invade the
  intestinal mucosa, they produce tissue
  destruction (ulcers).
• The organisms multiply and spread laterally
  underneath the intestinal epithelium to produce
  characteristic flask-shaped ulcers.
• These lesions are commonly seen in the cecum,
  transverse colon, and sigmoid colon.
• Amebae may produce similar lytic lesions if they
  reach the liver these lesions are commonly
  called abscesses.

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• Clinical presentations range from asymptomatic
  cyst passage to amebic colitis, amebic dysentery,
  ameboma, and extraintestinal disease.
• colicky abdominal pains and frequent bowel
  movements (68/day).
• Stools are blood stained and contain a fair
  amount of mucus.

By Dr Arun Aggarwal Gastroenterologist
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Hepatic Amebiasis

• Fever is the hallmark of amebic liver abscess.
• abdominal pain
• distention, and enlargement and tenderness of the
  liver.
• Changes at the base of the right lung, such as
  elevation of the diaphragm and atelectasis or
  effusion, may also occur.
• Laboratory examination findings are a slight
  leukocytosis, moderate anemia, high ESR and
  nonspecific elevations of hepatic enzyme
  (particularly alkaline phosphatase).
• Stool examination for amebae yields negative
  results.

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• Diagnosis is based on detecting the organisms in
  stool samples, sigmoidoscopically obtained
  smears, tissue biopsy samples, or, rarely,
  aspirates of a liver abscess.
• The most sensitive serologic test, indirect
  hemagglutination, yields a positive result years
  after invasive infection.

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• Two types of drugs are used to treat infection
  with E. histolytica.
• The luminal amebicides, such as iodoquinol,
  paromomycin, and diloxanide furoate, are
  primarily effective in the gut lumen.
• Metronidazole or other nitroimidazoles,
  chloroquine, and dehydroemetine are effective in
  the treatment of invasive amebiasis.
• All individuals with E. histolytica trophozoites
  or cysts in their stools, whether symptomatic or
  not, should be treated.
• Invasive amebiasis of the intestine, liver, or
  other organs requires the use of metronidazole
  (3050?mg/kg/24?hr divided tid PO for 10 days.

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Giardia
By Dr Arun Aggarwal Gastroenterologist
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• Giardia lamblia (also referred to as G.
  intestinalis and G. duodenalis) is a flagellated
  protozoan that infects the duodenum and small
  intestine.
• Clinical manifestations range from asymptomatic
  colonization to acute or chronic diarrhea and
  malabsorption.
• Giardia is a particularly significant pathogen in
  people with malnutrition, certain
  immunodeficiencies, and cystic fibrosis.

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• The life cycle of Giardia is composed of two
  stages trophozoites and cysts.
• Giardia infects humans after ingestion of as few
  as 10100 cysts.
• Cysts are passed in stools of infected
  individuals and may remain viable in water for as
  long as 2 mo.
• Giardia cysts are relatively resistant to
  chlorination and to ultraviolet light
  irradiation. Boiling is effective for
  inactivating cysts.

By Dr Arun Aggarwal Gastroenterologist
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Clinical Signs and Symptoms of Giardiasis

• Symptoms

• Frequency

• Diarrhea
• Malaise, weakness
• Abdominal distention
• Flatulence
• Abdominal cramps
• Nausea
• Foul-smelling, greasy stools
• Anorexia
• Weight loss
• Vomiting
• Fever
• Constipation

• 64100
• 7297
• 4297
• 3597
• 4481
• 1479
• 1579
• 4173
• 5373
• 1435
• 028
• 027

By Dr Arun Aggarwal Gastroenterologist
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• A definitive diagnosis of giardiasis is
  established by documentation of trophozoites,
  cysts, or Giardia antigens in stool specimens or
  duodenal fluid.
• Diagnostic testing include the use of polyclonal
  antisera or monoclonal antibodies against Giardia
  organismspecific antigens in EIA or
  immunofluorescent assays.
• PCR and gene probebased detection systems
  specific for Giardia have been used in
  environmental monitoring.

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• Asymptomatic excreters generally are not treated
  except in specific instances such as in
• outbreak control
• for prevention of household transmission by
  toddlers to pregnant women
• patients with hypogammaglobulinemia or cystic
  fibrosis
• in situations requiring oral antibiotic treatment
  where Giardia may have produced malabsorption of
  the antibiotic.

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• Metronidazole is the treatment most often
  prescribed in the United States for adults.
• Furazolidone is less effective than metronidazole
  but is often prescribed in children because it is
  available in liquid form.
• Paromomycin, a nonabsorbable aminoglycoside, is
  less effective than other agents but is
  recommended for treatment of pregnant women with
  giardiasis because of potential teratogenic
  effects of other agents.

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Approach to diarrhea
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• Assess the degree of dehydration and provide
  fluid and electrolyte replacement,
• Prevent spread of the enteropathogen
• In select episodes determine the etiologic agent
  and provide specific therapy if indicated.
• Information about oral intake, frequency and
  volume of stool output, general appearance and
  activity of the child, and frequency of urination
  must be obtained.

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• Data should be obtained about
• childcare center attendance
• recent travel to a diarrhea endemic area
• use of antimicrobial agents
• exposure to contacts with similar symptoms
• intake of seafood, unwashed vegetables,
  unpasteurized milk, contaminated water, or
  uncooked meats.
• Duration and severity of diarrhea
• stool consistency
• presence of mucus and blood
• other associated symptomatology, such as fever,
  vomiting, and seizures.

By Dr Arun Aggarwal Gastroenterologist
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EXAMINATION OF STOOL

• Stool cultures should be obtained as early in the
  course of disease as possible from patients in
  whom
• HUS is suspected,
• in patients with bloody diarrhea,
• if stools contain fecal leukocytes,
• during outbreaks of diarrhea
• in persons who have diarrhea and are
  immunosuppressed.

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Adjusting Fluid Therapy in Diarrhea

• AVERAGE COMPOSITION OF DIARRHEA
• Sodium 55mEq/L
• Potassium 25mEq/L
• Bicarbonate 15mEq/L
• APPROACH TO REPLACEMENT OF ONGOING LOSSES
• Solution D5 1/4 NS 15mEq/L bicarbonate
  25mEq/LKCl
•  Replace stool mL/mL every 16hr

By Dr Arun Aggarwal Gastroenterologist
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Adjusting Fluid Therapy for Emesis or Nasogastric
Losses

• AVERAGE COMPOSITION OF GASTRIC FLUID
• Na 60mEq/L
• K 10mEq/L
• Cl 90mEq/L
• APPROACH TO REPLACEMENT OF ONGOING LOSSES
• Solution D5 1/2 NS 10mEq/LKCl  
•  Replace output mL/mL every 16hr

By Dr Arun Aggarwal Gastroenterologist
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Fluid Management of Dehydration

• Restore intravascular volume
• Normal saline 20mL/kg over 20min (Repeat until
  intravascular volume restored)
• Calculate 24-hr water needs
• Calculate maintenance water
• Calculate deficit water
• Calculate 24-hr electrolyte needs
• Calculate maintenance sodium and potassium
• Calculate deficit sodium and potassium
• Select an appropriate fluid (based on total water
  and electrolyte needs)  
• Administer half the calculated fluid during the
  first 8hr, first subtracting any boluses from
  this amount
• Administer the remainder over the next 16hr
• Replace ongoing losses as they occur

By Dr Arun Aggarwal Gastroenterologist
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Treatment of Hypernatremic Dehydration

• Restore intravascular volume
• Normal saline 20mL/kg over 20min (Repeat until
  intravascular volume restored)
• Determine the time for correction based on the
  initial sodium concentration
• Na 145157mEq/L 24hr
• Na 158170mEq/L 48hr
• Na 171183mEq/L 72hr 
• Na 184196mEq/L 84hr
• Administer fluid at a constant rate over the time
  for correction
• Typical fluids D5 1/4 NS or D5 1/2 NS (both with
  20mEq/L KCl unless contraindicated)
• Typical rate 1.251.5 times maintenance

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Solution Glucose (mmol/L) Na (mEq/L) K (mEq/L) Cl (mEq/L) Base (mEq/L) Osmolality (mOsm/kg)
WHO solution 111 90 20 80 30 311
Rehydralyte 140 75 20 65 30 310
Pedialyte 140 45 20 35 30 250
Pediatric Electrolyte 140 45 20 35 48 250
Infalyte 70 50 25 45 34 200
Naturalyte 140 45 20 35 48 238
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Prevention.

• Patients who are hospitalized should be placed
  under contact precautions, including handwashing
  before and after patient contact, gowns when
  soiling is likely, and gloves when touching
  contaminated material.
• Patients and their families should be educated
  about the mode of acquisition of enteropathogens
  and methods to decrease transmission.
• Patients who attend childcare centers should be
  excluded from the center or cared for in a
  separate area until diarrhea has subsided.

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Isolation
STANDARD PRECAUTIONS

• Standard precautions, formerly known as universal
  precautions, are intended to protect health care
  workers from blood and body fluids and should be
  used whenever providing care.
• Standard precautions involve the use of
  barriersgloves, gowns, masks, goggles, and face
  shieldsas needed to prevent transmission of
  microbes associated with contact with blood or
  body fluids.

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• Contact precautions include gowns and gloves and
  single room isolation.
• Droplet precautions include masks for close
  contact (lt3?ft) and single room isolation.
• Cohorting of children infected with the same
  pathogen is acceptable.
• Airborne precautions include masks and single
  room isolation with negative-pressure
  ventilation.
• Transmission-based precautions are continued for
  as long as a patient is considered to be
  contagious.

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Questions
By Dr Arun Aggarwal Gastroenterologist
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• A 2-year-old child who attends day care presents
  with abdominal cramps and severe bloody diarrhea,
  which has been present for 2 days. He has no
  fever. Which infection is most consistent with
  this clinical picture
• a. Rotavirus
• b. Giardia lamblia
• c. E. coli O157H7
• d. Norvovirus infection
• e. Shigellosis

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• A three year old has just returned from Central
  America. You see him after five days of fever
  diarrhea which is described as green, bloody,
  foul-smelling, mucosy. He has pain on
  defecation. The preliminary report on the stool
  culture is non-lactose fermenters You suspect
• Pseudomonas
• E. coli
• Salmonella
• Proteus
• Aeromonas

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• A 10 week old afebrile infant has bloody
  diarrhea. The stool culture grows Salmonella. You
  would
• Perform an LP
• Treat with appropriate antibiotic
• Obtain a bone scan to rule/out osteomyelitis
• Treat only if child has significant toxicity or
  severe gastroenteritis
• Rule out HIV infection

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• Which of the following is LEAST frequent with
  rotavirus infection?
• Fever
• Vomiting
• Coryza preceding the diarrhea
• Blood and mucus in the stool
• Diarrhea lasting more than 48 hours

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• A 1 yr old boy is brought to you with vomiting
  and loose stools for the past 4 days. Initially,
  mother gave pedialyte, but for the last 24 hrs,
  the baby has been vomiting all feeds. Mother
  doesnt know when he last urinated. O/E child is
  sleepy and responds only when blood was
  withdrawn.
• Pulse 142/min, RR 32/min, wt 10 kg
• Skin turgor is decreased with obvious
  tenting. Nail beds were pink with prompt
  capillary refill.
• Which of the following would represent the
  best choice for initial fluid orders?
• D5W/ 0.2 NS _at_100cc/hr. Add 20 meq KCl after
  urination.
• D5W/ 0.45 NS to run at 150 cc/hr for the next 8
  hrs
• D5W/ 0.45 NS _at_100cc/hr for the next 8 hrs. Add
  20 meq KCl after urination
• NS _at_ 150 cc/hr for the next 8 hrs

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• During teaching rounds you come across a patient
  with Rota virus diarrhea. Patient continues to
  have diarrhea day 10 after onset. You tell the
  residents that the diarrhea is secondary to
  malabsorption due to loss of cells lining the
  villi. One smart resident asks you how long it
  would take for intestinal cells to turn over.
• 1 day
• 2-3 weeks
• 3-5 days
• 1-2 months
• 8-10 days

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• Results of a stool culture from a 2 yr old boy
  who has been hospitalized with bloody diarrhea
  indicate that the causative agent is Shigella sp.
  The boy is allergic to trimethoprim-
  sulfamethoxazole.
• Of the following the most appropriate
  antimicrobial agent to use for this patient is
• amoxicillin
• azithromycin
• cefdinir
• ciprofloxacin
• linezolid

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• Medication that can safely be used in case of
  acute diarrhea
• Loperamide
• Octreotide
• Racecadotril
• All of the above
• None of the above

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• Racecadotril enkephalinase inhibitor
• Enkephalins are endogenous pro- absorptive agents
  that directly inhibit the activity of adenylate
  cyclase on the enterocyte baselateral membrane.
• Racecadotril is a synthetic, potent inhibitor of
  enkephalinase, devoid of any effect on intestinal
  motility, thus without the potential to induce
  the bloating that can be associated with
  enteropooling.

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Things to remember..

• New WHO ORS
• Super ORS
• SGLT 1
• Feeding (BRAT)
• Medications
• Probiotics
• Antibiotics (for Shigella, cholera, Giardia,
  Yersinia)
• Zinc

By Dr Arun Aggarwal Gastroenterologist