| Aeromonas (PP): |
Aeromonas is a gram-negative rod
belonging to the Vibrionaceae
family. There are at least four species of Aeromonas with A. hydrophilia being
the most common isolated species in the U.S.1 2 |
Aeromonads are ubiquitous in fresh water environments. The number
present is dependant on the extent of sewage pollution and the ambient
temperature. Recent studies have directly
attributed Aeromonas as the cause of food-borne infections.
The following foods may harbor the organism: raw meat,
freshwater fish, shellfish and other seafood. Raw milk
can also be a source of infection.3 |
Definitive experimental evidence for the
causative role of Aeromonas in
gastrointestinal disorders is still
lacking. Although human volunteer studies are
inconclusive, epidemiological evidence has shown that the presence of
these organisms in
stools is significantly
more often associated
with diarrhea than with
the carrier state.4 5 |
Aeromonas gastroenteritis may affect both children and adults
with the highest seasonal incidence occurring in the
summer months. Symptoms tend to be generally
mild, self-limiting diseases with watery diarrhea.6 Bloody
stools have been reported. Aeromonas infections tend
to be more acute in children and more chronic in adults.7 8 |
Most Aeromonas species are generally susceptible to cephalosporins,
aminoglycosides, carbapenems, tetracyclines, trimethoprim-sulfamethoxazole and quinolones.9
Susceptibility must guide testing. |
| *Aeromonas hydrophilia/caviae |
| *Aeromonas veronii biovar sobria |
| *Aeromonas biovar veronii |
| *Aeromonas species |
|
Bacillus (PP): |
Bacillus species are spore forming, gram-positive rods belonging to theBacillaceae family.10 11 There are currently 50 valid species within the genus.12 |
Sources of the diarrheal type ofB. cereus food poisoning include: meats, pasta, vegetable dishes, desserts, cakes, sauces and milk.13 The emetic type of infection is predominately associated with oriental rice dishes. Pasteurized cream, milk pudding and pasta have occasionally been implicated.14 The incidence ofB. cereus infection is increased during the summer months.15 |
Although part of the normal flora,B.cereus has been established as an opportunistic pathogen.16 The gram-positive spore forming rods ofB.cereus elaborate enterotoxins.17 Both types of food poisoning result from spores that have survived cooking, then germinated, producing vegetative cells that have multiplied.18 NB, it is estimated that only half the isolated strains of B. cereus are enterotoxin positive.19 |
B. cereus is the etiological agent of two distinct types of food poisoning: 1) The diarrheal type, which is caused by a heat-labile enterotoxic complex. Symptoms include abdominal pain, and diarrhea 8-12 hours after ingestion of the organism.20 21 2) The emetic type, caused by a heat-stable enterotoxin. Nausea and vomiting usually occur 1-5 hours after ingestion.22 23 |
B. cereus is almost always susceptible to clindamycin, erythromycin and vancomycin.24 |
*Bacillus
cereus |
*Bacillus
species |
|
Meat dishes are a common source of infection in other species ofBacillus such asB. subtilis andB. licheniformis .25 |
As yet, no toxins or other virulence factors have been identified in association with the symptoms that accompany non-B. cereus species .26 |
B. licheniformis andB. subtilis are associated with food-borne diarrheal illness.27 |
|
Campylobacter jejuni
(P) |
Campylobacter are
gram-negative, non-spore forming rods belonging to the Campylobacterace ae family.28 In total there are 18
species and subspecies within the genus.29 |
Poultry is a key source of infection,
in particular chicken. Red meat and shellfish can also harbor the organism.30
Other sources include unpasteurized milk, and water contaminated by wild birds.31 |
Recognized as the
principle cause of diarrhea in humans. C. jejuni and C. coli are the most common species associated with diarrheal illness.32 The infective dose as
yet has not been clearly defined, but it is thought that as little as
1000 organisms are capable of causing infection.33 |
The incubation period can be 2
to 10 days, though is usually 2 to 5 days.34 Symptoms can include fever, abdominal cramping, diarrhea (often bloody) abdominal pain and fever. Relapses may occur in 5%-10% of untreated cases.35 |
Erythromycin is the
drug of choice for treating C. jejuni infections. Ciprofloxacin may be an alternative drug.36 |
| Candida (PP): |
The genus Candida is comprised of
approximately 200
different species.37
C. albicans is the
most commonly
isolated strain from
the GI tract.38 |
Most sources of Candida infection are thought to be of endogenous
origin.39
While yeast are ubiquitous in the
environment and are found on fruits,
vegetables and other plant materials,
contamination from external sources
is linked to patients and health care
workers.40 41 |
A normal inhabitant of the GI tract. May
become an
opportunistic pathogen
after disruption of the
mucosal barrier,
imbalance of the
normal intestinal flora
and/or impaired
immunity.42 43 44 45
Risk factors for
colonization include:
Antibiotics,
corticosteroids,
antacids, H2 blockers,
oral contraceptives,
irradiation, GI surgery,
Diabetes mellitus,
burns, T cell
dysfunction, chronic
stress and chronic renal
disease.46 47 48 49 |
The most common symptom attributable to non-invasive yeast
overgrowth is diarrhea.50
Symptoms of chronic candidiasis
affect four main areas of the
body:
Intestinal system – symptoms
include: diarrhea, constipation,
abdominal discomfort,
distention, flatulence and rectal
itching.
Genital Urinary system –
symptoms include: menstrual
complaints, vaginitis, cystitis
and urethritis.
Nervous system – symptoms
include: severe depression,
extreme irritability, inability to
concentrate, memory lapses and
headaches.
Immune system – symptoms
include urticaria, hayfever,
asthma, and external otitis.
Sensitivities to tobacco,
perfumes, diesel fumes and other
chemicals.51 52 |
Currently, standard texts provide no specific antifungal
guidelines for GI
overgrowth of
Candida.
Oral azoles have been
recommended for
extra intestinal
infections.
Susceptibility testing
is advised due to
increasing drug
resistance.53 54 |
| *Candida albicans |
| *Candida famata |
| *Candida glabrata |
|
|
| *Candida guilliermondii |
|
|
| *Candida krusei |
| *Candida lusitaniae |
| *Candida pseudotropicalis |
|
*Candida rugosa |
|
*Candida stellatoidea |
|
*Candida tropicalis |
|
*Candida zeylanoides |
| Citrobacter (PP): |
Citrobacter is a
gram-negative rod
belonging to the Enterobacteriaceae family.55
Citrobacter contains 9 named species and two unnamed genomospecies.56
The genus
Clostridium are anaerobic gram-
positive, spore-forming bacteria.66 |
Common in the environment and
may be spread by person-to person
contact. Several outbreaks have occurred in babies in hospital units.57 58
Isolated from water, fish, animals and food.59
The organism has many natural
habitats including hay, soil, cows, horses and dogs.67
Almost 50% of neonates carry this organism asymptomatically as part of
their gastrointestinal flora during the
first year of life. This rate decreases sequentially to about 3% in adults
and less in children over two years of age.68 69 |
Citrobacter is
considered an
opportunistic pathogen and therefore can be found in the gut as part of the normal flora.60
C. difficile is the major
cause of antibiotic-associated diarrhea and
pseudomembranous colitis and the most
common cause of
hospital-acquired diarrhea.70
Isolation of C. difficile
without a positive toxin
test has little clinical
value. It is important to
test for both toxins A
and B in the stool.
Toxin A is an enterotoxin and toxin B
is a cytotoxin that
inhibits bowel motility.
It is thought that both
toxins are important in the pathogenesis.71 72 |
Citrobacter has occasionally
been implicated in diarrheal
disease, particularly C. freundii and C. diversus and C. koseri. 61
Mild cases of C. difficile disease
are characterized by frequent, foul-smelling, watery stools.
More severe symptoms, indicative of pseudomembranous
colitis, include diarrhea that
contains blood and mucous, and abdominal cramps.73 |
Currently, standard
texts provide no
specific antimicrobial guidelines for GI overgrowth of Citrobacter. 62 63 Carbapenems and fluroquinolones are the recommended antibiotics for extra-intestinal sites.64 65
Severe C. difficile
intestinal disease is usually treated with
oral vancomycin or metronidazole.
However,
antimicrobial therapy often results in
relapse of the disease.74
In addition, there is
concern that oral
vancomycin can lead
to the emergence of
vancomycin-resistant Enterococci. 75 |
| *Citrobacter amalonaticus |
| *Citrobacter braakii |
| *Citrobacter diversus |
| *Citrobacter freundii |
|
*Citrobacter freundii/youngae |
| *Citrobacter freundii complex |
| *Citrobacter koseri |
| *Citrobacter species |
|
Clostridium difficile
(PP) |
|
|
|
Cryptococcus (PP): |
Cryptococcus is a yeast-like fungus, which closely resembles the genus Candida. 76
The genus contains a number of species, of which only C. neoformans is considered to be a human pathogen.77
The genus Edwardsiella is a gram-negative rod that belongs to the Enterobacteriaceae family.86
To date there are
three species, though only E. tarda is associated with human disease.87 |
Found in the excreta of pigeons and other birds in most parts of the world. The yeast is associated with aged bird droppings that have accumulated over a long period of time on window ledges, vacant buildings and other roosting sites.78
Isolated from cold-blooded animals such as fish and reptiles and their environment.88
Infection is more common in tropical and subtropical environments and developing countries.89 |
Can be an opportunistic pathogen, predominately in the immunocompromised host.79
Cryptococcus is considered one of the defining diseases of AIDS. Patients with Cryptococcus and serologic evidence of HIV are considered to have AIDS.80
E. tarda is considered an opportunistic pathogen, occasionally causing acute gastroenteritis.90 91 |
Diarrhea has been associated with Cryptococcal infection.81
Usually infection occurs in the tissue of the central nervous system but occasionally can produce lesions in the skin, bones, lungs, or other internal organs.82
Diarrheal disease is associated with infection, with a clinical picture similar to Salmonella enteritis.92 Isolation of the E. tarda is more common in young children and the elderly.93 |
Currently, standard texts provide no specific antimicrobial guidelines for GI overgrowth of Cryptococcus. 83 84 Fluconazole is considered the primary antimicrobial agent in extraintestinal sites.85
If antibiotic treatment is required, ampicillin, trimethoprim-sulfamethoxazole and ciprofloxacin have all been found to be effective agents.94 |
|
*Cryptococcus albidus |
|
*Cryptococcus humicolus |
|
*Cryptococcus laurentii |
|
|
*Cryptococcus luteolus |
|
*Cryptococcus neoformans |
|
*Cryptococcus species |
|
*Cryptococcus terreus |
|
*Cryptococcus uniguttulatus |
|
Edwardsiella tarda(P) |
|
E.coli Shiga-like toxin |
Shigatoxin-producing E. coli strains are
referred to as STEC. This includes the
0157 and many other STEC serogroups. 95
In total, at least 100 serotypes have been isolated from
persons with diarrhea. 96 |
0157 STEC colonize dairy and beef cattle, which is why ground beef is the most
common infection vehicle. However, raw milk, sausage, roast beef,
unchlorinated water, apple cider, and raw vegetables have also been implicated. 97 |
E. coli 0157:H7 and 0157:non-motile (0157
STEC) produce one or more Shiga toxins and, are
the most commonly identified diarrheagenic E.coli isolates in North America and Europe. 98
Non-toxin-producing strains are normal in the
human intestine. 0157 STEC spreads easily from person to person because the infectious dose is low. 99 |
The STEC strains cause a spectrum of illness that can present as mild
non-bloody diarrhea, severe bloody diarrhea (hemorrhagic colitis), and
hemolytic uremic syndrome (HUS).100 About 6% of 0157 STEC patients develop HUS. 101 |
Antimicrobial therapy for 0157 STEC has
NOT been demonstrated to be effective or safe,
except for cases of cystitis and pyelonephritis. 102
Antimicrobial therapy for intestinal disease
may enhance toxin release and predispose for HUS. 103 |
|
Enterobacter cloacae (PP) |
Gram-negative rod that is part of the Enterobacteriaceae family. 104
There are 14 species in the genus, though only E. cloacae has been associated with
GI infection. 105 106 |
Widely distributed in the environment. Water, soil, sewage and cornstalks have all been identified as sources of contamination.107 108 |
Usually considered a commensal organism; however, strains of E. cloacae have been shown to produce a heat-stable
toxin similar to that produced by E.coli. 109 |
Has been associated with diarrhea in children. 110 111 |
Currently, standard texts provide no specific antimicrobial guidelines for GI overgrowth of Enterobacter. 112 113
Carbapenems are recommended for extra-intestinal sites. 114 |
|
Geotrichum (PP): |
Geotrichum are yeast belonging to the Endomyceteaceae family. There are several species within the
genus, of which G. candidum is the most common.115 |
This organism can be found in soil, dairy products and in human skin and mucosae. 116 |
Usually only considered an opportunistic pathogen in immune-compromised hosts. 117 118
Geotrichum candidum is
the etiological agent of Geotrichosis. 119 |
Symptoms of Geotrichum infection have been associated with diarrhea and enteritis. 121 122
Symptoms of Geotrichosis may resemble those of candidiasis. 123 |
Currently, standard texts provide no specific antifungal guidelines for GI overgrowth of Geotrichum. Oral azoles and have been
recommended for extra intestinal infections. Susceptibility testing is advised owing to increasing drug resistance. 124 125 |
|
*Geotrichum candidum |
|
*Geotrichum capitum |
|
|
|
|
|
|
Geotrichum may also play a role in IBS.120 |
|
|
|
*Geotrichum species |
|
Hafnia alvei (PP) |
Hafnia is a gram- negative rod considered part of
the Enterobacteriaceae family. There is only one
species of Hafnia– H. alvei–which was previously a
member of the Enterobacter
genus.126 |
Commonly found in warm-blooded
animals, particularly birds. Other environmental sources include
contaminated water, sewage, food, and dairy products.127 |
This organism is a
natural inhabitant of the GI tract in humans.
Hafnia strains are opportunistic pathogens; community and hospital outbreaks
have been associated with GI infection.128 |
Diarrheal illness has been
associated with outbreaks and virulence factors similar to
toxigenic E.coli have been described.129 |
Hafnia strains are
usually susceptible to piperacillin,
imipenum, quinolones and the newer cephalosporins.130 |
|
Helicobacter pylori
(P) |
The genus
Helicobacter are gram-negative, non-spore forming
rods. There are currently 19 species within the genus.131
Seroprevalence of H. pylori varies from 20% in young adults in developed
countries to sometimes more
than 90% in developing countries.132 |
Reservoirs of infection include the
intestinal tract of mammals and birds. Mode of transmission is usually via the fecal-oral or oral-to-oral route.133 |
H. pylori causes chronic
gastritis and predisposes to gastric and duodenal ulcers.
Increased risk of gastric carcinoma is associated with infection.134
It is estimated that 50%
of the world’s population is infected with H. pylori. 135 |
Those infected with H. pylori
may develop acute gastritis with symptoms of abdominal pain, nausea and vomiting, usually
within two weeks of infection. Many patients have recurrent abdominal symptoms (non-ulcer dyspepsia) without ulcer disease.136 |
Cure rates require
multi-drug regimens along with antacid medications.137
The most successful treatment includes a combination of metronidazole, omeprazole and clarithromycin.138 |
|
Morganella morganii
(PP) |
Morganella is
gram-negative rod belonging to the Enterobacteriaceae family.187
Currently, there are 3 species within the genus.188 |
M. morganii originates from the gill
and skin of fish. It is possible that it may cross-contaminate during handling of fish in processing plants and restaurants.189 |
The role of Morganella
as an etiological agent in diarrheal disease is controversial. Although Morganella constitutes part of the normal flora,
in certain hosts it may be a potential pathogen.190 191
Recently it was shown
that the majority of clinical isolates of Morganella belonged to the subsp Morganii. 192 |
Diarrhea has been associated
with infection of this organism.193 194 |
Currently, standard
texts provide no specific antimicrobial guidelines for GI overgrowth of Morganella. 195 196
Carbapenems, 3rd and 4th generation cephalosporins and
fluroquinolones are the agents
recommended for extra-intestinal infections.197 |
|
Plesiomonas
shigelloides (PP) |
Plesiomonas is a
gram-negative rod belonging to the Vibrionaceae family, though it does contain the Enterobacteriaceae
antigen. P. shigelloides is the only species in the genus.198 199 |
Usually found in fresh water or
estuarine water. Occurs in fish, shellfish, oysters, toads, snakes, monkeys, dogs, cats, goats, pigs, poultry, and cattle.200
There is a low incidence of Plesiomonas shigelliodes in the US and Europe.201
In Asia, however, the organism
contributes to a significant proportion of traveler’s diarrhea.202 203 |
P. shigelloides is not a
natural inhabitant of the GI tract.204
Although feeding studies with humans resulted in the excretion
of the organism (but not diarrhea) from about one third of the volunteers, several
epidemiological studies suggest that Plesiomonas is a
possible agent in GI disease. It has been isolated from human
stool specimens in the absence of symptoms
and may be difficult to attribute as the cause of
diarrhea in some cases.205 |
Symptoms range from short- lived episodes of watery stools to several days of dysentery-like
diarrhea. Has not been reported to affect specific age groups more often than others.206 207
Accompanying symptoms vary and may include abdominal pain, nausea, vomiting, chills, headaches and dehydration. 208
Infections with P. shigelloides are usually self-limiting, lasting
up to 7 days and occasionally longer.209 210 |
P. shigelliodes is
susceptible to most major classes of antibiotics, including trimethoprim, cephalosporins, and quinolones.211 |
|
Proteus (PP): |
Proteus is a gram-negative rod belonging to the Enterobacteriaceae family.212
10 species in total are attributed to the
genus of which P. mirabilis is
considered the most important.213 |
Food has been implicated as a vehicle of infection.214 |
Part of the normal flora of the GI tract, though has been shown to be an independent causative agent of
intestinal disorders.215
May also play a role as
an opportunistic organism in enteric
infection due to other pathogens.216 |
Occasionally implicated in diarrheal disorders.217 218
Recently, it has been suggested that P. mirabilis may be an
etiological agent in rheumatoid arthritis.
The mechanism may be related to the molecular cross reactivity
between P. mirabilis and the HLA antigens, specifically
HLA-DR4.219 |
Currently, standard texts provide no specific antimicrobial guidelines for GI overgrowth of
Proteus. 220 221
Ampicillin is
recommended for extra-intestinal
infections of P. mirabilis, followed
by trimethoprim- sulfamethoxazole.222 |
|
*Proteus mirabilis |
|
*Proteus penneri |
|
*Proteus vulgaris |
|
Provedencia
alcalifaciens (PP) |
Provedencia is a
member of the Enterobacteriaceae family of which
there are 5species.223 224 |
GI tract infection with P.
alcalifaciens has been associated with overseas travel.225 |
Provedencia is not
normally present in a healthy GI tract.226
Its pathogenic role may lie in the ability of the
organism to take advantage of conditions created by other infectious microbes.227 |
This organism has been
implicated as a cause of diarrhea.228 229
P. alcalifaciens is thought to induce invasive diarrhea in
patients by invading cells in the intestine, thus producing inflammatory changes in the ileum.230 |
Currently, standard
texts provide no specific antimicrobial guidelines for GI
overgrowth of Providencia. 231 232
3rd generation cephalosporins and fluroquinolones are recommended for
extra-intestinal sites.233 234 |
|
Pseudomonas (PP): |
Pseudomonas species are aerobic,
non-spore forming gram-negative rods.235
There are 10 species in the
genus, though P. aeruginosa is considered the
most important pathogen.236 |
Found in water and soil as well as fruits and vegetables.
Bottled water can be a common source of infection. Because the organism is able to survive aqueous environments, it is an important nosocomial pathogen.
Pseudomonas can also be found on a
number of surfaces and in aqueous solutions.237 |
Pseudomonas is considered an
opportunistic pathogen.238
Animal studies have isolated an enterotoxin thought to be
responsible for causing diarrhea.239 |
Associated with diarrheal infection, particularly in the
immunocompromised host.240 241
Pseudomonas can also be an etiological agent of antibiotic-associated diarrhea.242 |
Ciprofloxacin is recommended for the treatment of Pseudomonas-induced antibiotic-associated colitis.243
Pseudomonas is
usually susceptible to antipseudomonal penicillins,
aminoglycosides, carbapenems, 3rd generation
cephalosporins and gentamycin.244 245 |
|
*Pseudomonas aeruginosa |
|
*Pseudomonas species |
|
Saccharomyces
cerevisiae (PP) |
Saccharomyces are
yeast belonging to the Sacccharomycetac
eae family. Currently there are 18 species within the genus of which S. cerevisiae is the most common.246 247 |
S. cerevisiae is a commonly used
industrial microorganism and is ubiquitous in nature, being present on fruits and vegetables.
Also known as Baker's Yeast or Brewer's Yeast, this organism has been used for centuries as leavening for bread and as a fermenter of alcoholic beverages.248 249 |
S. cerevisiae commonly
colonizes mucosal surfaces, and is rarely considered an
opportunistic pathogen.250 251 252
Severe immunosuppression, prolonged hospitalization, and
antibiotic therapy are all associated
withSaccharomyces infection..253 Overgrowth may be
associated with dietary ingestion of S.
cerevisiae and/or S. boulardii as part of a |
Studies have shown that patients
with S. cerevisiae overgrowth usually have an underlying disease.254
Disseminated infections are thought to arise from the gastrointestinal tract.255 |
Currently standard
texts provide no specific antifungal guidelines for GI
overgrowth of Saccharomyces. |
|
Salmonella (P): |
Salmonella are members of the Enterobacteriaceae family and as such are
gram-negative rods.256 |
Animals and birds utilized for meat are subject to contamination with
Salmonella. Eggs, cereals and cereal products are other sources of
contamination.257
The incidence of infection increases over the summer, and is
predominantly associated with acute diarrhea in infants.258 |
Salmonella are considered frank pathogens in humans. These organisms are NOT
part of the normal bowel flora. Salmonella species are acid-sensitive, invasive,
and produce enterotoxins in the GI tract. Several thousand cells may be needed
to cause infection.259 |
Gastroenteritis and diarrhea are caused by more than 2000
serotypes producing infections limited to the mucosa and submucosa of the GI tract. S. typhimurium and S. enteritidis are the serotypes most common in the US. Bacteremia and extraintestinal infections occur by spread from the GI tract, and any serotype is capable of causing bacteremia. 260 261 |
Antimicrobial therapy is not recommended for uncomplicated Salmonella gastroenteritis.262
Antimicrobial therapy is warranted in cases of bacteremia. Enteric fever (typhoid fever) is characterized by prolonged fever and multisystem involvement. This is a life-threatening infection caused by S. typhi or S. paratyphi.
Antimicrobial
therapy is needed in cases of typhoid fever.263 |
|
*Salmonella Group C |
|
and D |
| *Salmonella arizonae |
| *Salmonella group A |
| *Salmonella group B |
| *Salmonella group C |
| *Salmonella group D |
| *Salmonella group E |
| *Salmonella group E + G |
| *Salmonella paratyphi A |
| *Salmonella paratyphi B |
| *Salmonella paratyphi C |
| *Salmonella species |
| *Salmonella typhi |
|
Serratia marcesens (PP) |
Serratia is a gram-negative rod belonging to the Enterobacteriaceae family. 264 |
Serratia is more often associated with nosocomial infection, and seldom occurs in the community. The most common route of transmission is hand-to-hand spread via nurses, physicians and other healthcare workers. 265 |
A natural inhabitant of the GI tract, though on occasion can become an opportunistic pathogen.266 |
In neonates the gastrointestinal system is an important source of the organism. 267 |
Currently, standard texts provide no specific antimicrobial guidelines for GI overgrowth of Serratia. 268 269 Third generation cephalosporins, carbapenems, and fluroquinolones are the recommended antibiotics for extra-intestinal infections.270 |
|
Shigatoxin-producing
E.coli (STEC )-See E.coli Shiga-like
toxin. |
|
|
|
|
|
|
Shigella (P): |
Shigella are members of the Enterobacteriaceae family. There are 4 serogroups that have historically been treated as species: -S. dysenteriae
(Serogroup A) -S. flexneri
(Serogroup B) -S. boydii (Serogroup C) -S. sonnei
(Serogroup D).271 |
Spread from person to –person by the fecal-oral route, especially in overcrowded areas and areas with poor sanitary conditions. Ingestion is also a primary source of infection. 272
A predominant organism responsible for acute diarrheal disease in infants and children. 273 |
Shigella is only found in humans at times of infections and is NOT part of the normal bowel flora. All species are considered frank pathogens in humans. 274 |
Symptoms can range from mild to explosive diarrhea. It is somewhat acid-resistant, invades epithelial cells, and produces toxins. Less than 100 cells are required to initiate infection.275 276
S. dysenteriae is rare in the US
and causes classic dysentery, producing the Shiga toxin.
S. sonnei is most common in the US, and usually produces only a watery diarrhea. 277 |
Shigella infections are often treated with antibiotics, and antimicrobial susceptibility testing is recommend owing to widespread resistance. 278
Resistant strains are usually susceptible to
the fluroquinolones. 279 |
|
*Shigella boydii |
|
*Shigella dysenteriae |
|
*Shigella flexneri |
|
*Shigella sonnei |
|
*Shigella species |
|
Staphylococcus
aureus (PP) |
Members of the
genus Staphylococcus are gram-positive
cocci. Currently, the genus is
composed of 32 species and 15 subspecies.280 |
Foods that require considerable
handling during preparation or that are kept at slightly elevated temperatures after
preparation are frequently involved in staphylococcal food poisoning.
The key foods associated with staphylococcal food poisoning include meat and meat
products; poultry and egg products; salads such as egg, tuna, chicken,
potato, and macaroni; bakery products such as cream-filled
pastries, cream pies, and chocolate éclairs; sandwich fillings; and milk and dairyproducts.281 282 |
Food poisoning is often
attributed to the staphylococcal enterotoxin.283
The toxin produced by the bacteria is very heat-stable and therefore not easily
destroyed by heat at normal cooking temperatures. The toxin
can remain, despite the organism being destroyed.284
There is considerable variation in
susceptibility to the enterotoxin in adults. Children and the elderly
have the highest degree of susceptibility. 285 |
Symptoms of staphylococcal
food poisoning usually appear within 1 to 6 hours after ingestion.
The individual response to the toxin may vary and depends
upon the amount of contaminated food eaten, the amount of toxin ingested, and general health status.286
Nausea, vomiting, abdominal cramping, and diarrhea are the most common symptoms.
In more severe cases, headache, muscle cramping, and
changes in blood pressure and pulse rate may occur.287
Recovery generally takes two days. It is not unusual for
complete recovery to take three days and sometimes longer.288 289 |
In most cases,
treatment for S. aureus infection is not necessary and
complete recovery usually occurs after
cessation of symptoms.290 |
|
Vibrio (PP): |
Vibrio are members of the Vibrionaceae family and as such are gram negative rods.291
There over 35 species within the genus, of which only about one third are pathogenic for humans.292 |
Pathogenic Vibrio are part of the autochthonous microbial flora in brackish and marine environments in temperate or tropical regions. V. cholerae and V. mimicus may be found in fresh water and in birds and herbivores.293 |
Cholera is caused by V. cholerae 01.294
Gastroenteritis is classically associated with V. cholerae non01, V. parahaemolyticus, V. hollisae, V. mimicus, V. fluvialis, V metschnikovii, and V. furnissii. 295 |
While classic cholera is rare in the US, the rice-water stool remains the characteristic symptom, among others and its infectious dose is quite large.296
Gastroenteritis caused by other Vibrio sp. presents as diarrhea and may be accompanied by cramps, nausea, vomiting and fever.297 |
Antimicrobial therapy reduces the frequency and duration of the diarrhea and shortens the post-infective period of shedding of V.cholerae. 298
Tetracycline or less commonly furazolidone are
drugs of choice, though antibiotic resistance is
increasing.299 300 |
|
*Vibrio cholerae |
|
*Vibrio fluvialis |
|
*Vibrio furnissii |
|
*Vibrio hollisae |
|
|
*Vibrio metschnikovii |
|
*Vibrio mimicus |
|
*Vibrio parahaemolyticus |
|
*Vibrio species |
|
Yeast not candida (PP):
|
Yeast are unicellular, budding cells and are usually round
to oval in shape, though some forms have demonstrated elongated and irregular shapes.301 |
Yeast are ubiquitous in the environment and can be found on fruits, vegetables and other plant materials.302
They can also live as normal inhabitants both within and on the body.303
|
Less common yeast such as those outlined in this section should only be considered
opportunistic pathogens in the immuno compromised host. 304 305 306 307 308 309 310 311 312 |
Disseminated infections may include the intestinal tract and are usually associated with immunosuppressive diseases or
conditions such as leukemia, organ transplant, multiple myeloma, aplastic
anemia, diabetes mellitus with ketoacidosis, ICU patients, lymphoma, solid tumors and AIDS.313 314
Immunosuppressive therapy such as corticosteroids, chemotherapeutic agents and cyclosporine can also enhance fungal overgrowth.315 |
Currently, standard texts provide no specific antifungal guidelines for GI
overgrowth of the fungi mentioned.316 317
Treatment is at the discretion of the practitioner, and should be based upon clinical symptoms and a positive reculture of the organism. |
|
Blastoschizomyces: |
|
*Blastoschizomyces capitatus
|
|
Hansenula anomala |
|
Pichia ohmeri |
|
|
Rhodotorula |
|
*Rhodotorula glutinis |
|
*Rhodotorula rubra |
|
*Rhodotorula species |
|
Trichosporon |
|
*Trichosporon pullulans |
|
*Trichosporon species |
|
Yersinia (PP): |
Yersinia are gram-negative
enteropathogenic bacilli that belong to the Enterobacteriaceae family.318
At present, there
are at least 10 species within the Yersinia genus.319 |
Y. pseudotuberculosis is found naturally in numerous wild and
domestic mammals and birds. Y. enterocolitica can be found in all warm-blooded wild, domestic and pet animals and occasionally in some fish. Pigs are important reservoirs for the human strains of Y. enterocolitica. 320
Infections may be acquired by ingestion of contaminated food or
water, or, rarely by direct person-to- person transmission in schools and hospitals.321 |
Intestinal yersiniosis may present in three
clinical forms: enteritis, terminal ileitis, or mesenteric lymphadenitis causing “pseudoappendicitis” and septicemia.322
Y. entercolitica and Y. pseudotuberculosis are most commonly
isolated from cases of gastroenteritis. Both would be considered significant isolates from
stool. Both of these organisms show preference for
lymphatic tissue and can spread via the bloodstream.323
Yersinia infection has been shown to induce chronic inflammatory
bowel disorders such as chronic diarrhea and
IBD. Rheumatoid arthritis, reactive
arthritis and unspecified arthralgias have also
been noted after Yersinia infection.324 325 |
Watery and sometimes bloody stools, fever, vomiting,
abdominal pain are common with Y. enterocolitica, particularly in adults and less frequently in children but rarely in Y. pesudotuberculosis infection which is more common in children exhibiting terminal
ileitis, lymphadenitis, and pseudoappendicitis.326
Animal and in-vitro studies have isolated an antigen designated Yersinia pseudotuberculosis mitogen (YPM) that is capable
of increasing epithelial permeability.327
Chronic GI disease (eg
intermediate colitis, UC, CD may follow Y. enterocolitica infection, though the exact role
this organism plays has not been fully elucidated.328 329 330 331 |
Intestinal infections with Y. enterocolitica and Y. pseudotuberculosis are usually self-limiting and do not require antibiotic therapy. In cases of
complicated gastroenteritis, doxycycline or
trimethoprim- sulfmethoxazole are the antibiotics of choice.332 |
| *Yersinia enterocolitica |
|
*Yersinia pseudotuberculosis |
|
*Yersinia species |
|
BecomeHealthyNow.com Home Page
Print This
Chart