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26 year old female from Texas presenting with
loose stools and bloating for 2.5 weeks. She
noticed that she also has intermittent dull
abdominal pain 3/5 relieved by bowel
movements and exacerbated with meals. She
denies fever, chills, significant weight loss and
blood in the stools. No other sick contacts at
home. Hx of travel to Mexico one month ago.
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ROS: Negative, except as above
Allergies: NKDA
PMH: Chlamydia treated with doxycycline 1 year
ago.
PSH: tonsillectomy at age 10.
SH: graduate student; no tobacco or illicit drugs. 23 glasses of wine monthly. OBGYN hx: LMP 2
weeks ago, lasts 5 days and is usually regular.
Sexual hx: sexually active with boyfriend. 7 total
sexual partners in her lifetime. Contraception:
progesterone/estrogen pills. Condoms used
occasionally.
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Infectious
- Viruses ( HIV, CMV, HIV, rotavirus etc)
- Bacteria ( E. coli, salmonella, shigella, food borne etc)
- Parasites: Giardia, Amebiasis, Helminths.
IBD
- Crohn’s disease
- Ulcerative colitis
Functional
- Irritable bowel syndrome
- Biliary colic
Autoimmune
-Gluten enteropathy
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Vitals: T 98.1, BP 115/70, HR 80, RR 14, O sat 100%
General: Alert and oriented x3, in no distress.
HEENT: Normocephalic, PEERLA, EOMI, TM clear,
nasal and oral mucosa moist. No oral thrush.
Neck: Supple, no cervical lymphadenopathy.
Cardiovascular: RRR, normal s1 s2, no murmurs or
gallops. Radial pulses 2+
Chest: Lungs clear bilaterally. No chest tenderness.
Abdominal: BS+, soft, bilateral lower quadrant
tenderness. No rebound tenderness. No tenderness at
McBurney’s point and negative Murphy’s sign.
Skin: no rashes.
Rectal Exams: hemeoccult negative.
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CBC normal with no eosinophilia.
BMP normal.
Stool microscopy for ova and parasites:
pending
Rapid HIV test: negative.
RUQ U/S: negative for gallstones
Stool microscopy ( for
ova and parasites)
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Cysts are the infectious form.
Trophozoites usually attach to
the wall of the small intestine
leading to malabsorption, bloating
and flatulence.
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Trophozoite
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Protozoan parasite that can cause transient or
chronic diarrhea worldwide.
Most susceptible population are travelers,
immunocompromised individuals and those
living in poor sanitary conditions and with
insufficient water systems.
Transmission: water, food or fecal-oral
transmission between infected individual.
Clinical presentation: Diarrhea, malaise,
abdominal cramps and weight loss.
 Diagnosis:
- Stool microscopy: sensitive and specific.
- Immunoassays: highest sensitivity. Used if stool
microscopy results are not definitive.
- Duodenal histopathology: villous atrophy
 Treatment: Metronidazole for 5-7 days. May
acquire transient lactose intolerance so advice to
avoid lactose containing products for a few weeks.
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