WikEM - User contributions [en]

Traveler's diarrhea

2014-09-29T17:16:19Z

Kldrake: /* Traveler's */

==Background==
*Most respond to antibiotics
*as duration of diarrhea increases, higher chance of parasitic cause

==Differential Diagnosis==
===Traveler's===
#[[Giardia lamblia]]
#[[Cryptosporidiosis]]
#[[Entamoeba histolytica]]
#[[Cyclospora]]

{{Template:Diarrhea DDX}}

==Diagnosis==
# dysentery if stool bloody, fvr or wbc in stool- invasive inflamm enteropathy
# has abrupt onset, metastatic lesions, reactive arthopathies, or campylobacter assoc guillain barre- maybe flouroquinolone resis esp in SE Asia
# amoebic dysentery insidious and can get amoebic liver abscess
# if do not find infc cause of dysentery, eval pt for IBD or CA
# prolonged diarrhea and malabsorption- giardia or tropical sprue- does not respond to removal of gluten from diet- tx with tetra and folate
# also consider postinfectious disaccharidase deficiency or irritable bowel dz
# if diarrhea starts >1 mo after travel- not caused by travel

==Treatment==
===Antibiotics===
{{Travelers Diarrhea Antibiotics}}

===Antimotility agent===
*Only for nonpregnant adults with no fever or blood in stool
*[[Loperamide]] 4mg PO after each loose stool (Max: 16mg/day)

===Pediatrics===
'''Antibiotic Options:'''
{{Travelers Diarrhea Pediatric Antibiotics}}

==See Also==
*[[Diarrhea]]
*[[Diarrhea (Peds)]]
*[[Travel Medicine]]

==Source==
<references/>

[[Category:GI]]
[[Category:ID]]
[[Category:TropMed]]

Template:Diarrhea DDX

2014-09-29T17:15:38Z

Kldrake: /* Infectious */

=== Noninfectious ===
#[[GI Bleed]]
#[[Appendicitis]]
#[[Mesenteric Ischemia]]
#[[Diverticulitis]]
#[[Adrenal Crisis]]
#[[Thyroid Storm]]
#[[Toxidromes|Toxicologic exposures]]
#Antibiotic or drug-associated

=== Infectious ===

#Viral (e.g. rotavirus)
#Bacterial
##[[Campylobactor]]
##[[Shigella]]
##[[Salmonella]] (nontyphi)
##[[E. coli]]
##E. coli 0157:H7
##[[Yersinia]]
##[[Vibrio cholerae]]
##[[Clostridium Difficile]]
#[[Parasitic]]
##[[Giardia lamblia]]
##[[Cryptosporidium]]
##[[Entamoeba histolytica]]
#Toxin
##[[Staphylococcus aureus]]
##[[Bacillus cereus]]

Giardia lamblia

2014-09-29T17:11:09Z

Kldrake: page links

=Background=
*Flagellated protozoan
*Most common cause of parasitic diarrhea worldwide
*Transmitted by water contaminated with feces (human, beaver, muskrat, dogs, raccoons, etc)
*Common among campers and is also known as “backpacker’s diarrhea”
*Common in travelers to former Soviet Union, Caribbean, Latin America, India, Africa
*Infection rate is twice as high during summer months
*Also may be transmitted by contaminated food or close physical contact (sexual activity, daycare centers, etc)
*Patients with decreased gastric acidity, immunoglobulin deficiency, or immunocompromise are more susceptible
*Other names: “beaver fever”, “the Trotskys” (common in travelers to Leningrad) <ref>Marx, John A., Robert S. Hockberger, Ron M. Walls, James Adams, and Peter Rosen. "Chapter 94 -- Gastroenteritis." Rosen's Emergency Medicine Concepts and Clinical Practice. Philadelphia: Mosby/Elsevier, 2010. Print.</ref> <ref>Tintinalli, Judith E., and J. Stephan. Stapczynski. "Chapter 156 -- World Traveler." Tintinalli's Emergency Medicine: A Comprehensive Study Guide. New York: McGraw-Hill, 2011. Print.</ref> <ref>Tintinalli, Judith E., and J. Stephan. Stapczynski. "Chapter 154 -- Foodborne and Waterborne Diseases." Tintinalli's Emergency Medicine: A Comprehensive Study Guide. New York: McGraw-Hill, 2011. Print.</ref>

=Pathophysiology=
*Trophozoites infect duodenum, jejunum, and ileum where they form cysts
*Cysts are passed in feces; viable for long periods of time
*A single diarrheal stool may contain hundreds of millions of cysts or parasites

=Clinical Presentation=
*Often asymptomatic
*Most common symptoms include:
**Abdominal distension
**Colicky pain
**Flatulence
**Diarrhea (pale, loose, floating, foul odor)
**Borborygmi
*No blood or mucus in stool
*Sudden onset after incubation period of 1-3 weeks
*Symptoms usually resolve in 7-10 days
*85% of the time infection resolves spontaneously within 6 weeks
*May cause chronic malabsorption-like illness, especially in those with immunoglobulin deficiency
*Chronic infections cause weight loss, anemia, lactose intolerance

=Diagnosis=
*Normal WBC, no eosinophilia
*Stool O&P
**Motile trophozoites or cysts
**Able to diagnose infection readily in acute illness
**More difficult to diagnose in chronic or asymptomatic infection
*Antigen testing with ELISA, DFA, etc starting to replace microscopic examination with similar cost <ref>http://www.ncbi.nlm.nih.gov/pubmed/22632642</ref>
*Suspect protozoan illness in patients with diarrhea > 2 weeks

=Differential Diagnosis=
*Viral infection (e.g. rotavirus)
*Bacterial diarrhea
**[[Campylobacter]]
**[[Shigella]]
**[[Salmonella]]
**[[E. Coli]]
**[[E. Coli O157:H7]]
**[[Yersinia]]
**[[Vibrio cholera]]
**[[Clostridium difficile]]
*Parasitic infection
**[[Cryptosporidium]]
**[[Enteromonas hominis]]
**[[Entamoeba histolytica]]
*Toxin-mediated
**[[Staphylococcus aureus]]
**[[Bacillus cereus]]

=Management=
*Metronidazole
**Adult: 250 mg TID x 7-10 days
**Children: 5 mg/kg TID x 7 days (max dose 500 mg TID)
*Albendazole <ref>http://www.ncbi.nlm.nih.gov/pubmed/23235648</ref>
**400 mg PO daily x 5-10 days
*Tinidazole
**Adult: 2 grams PO x 1 dose
**Children: 50 mg/kg PO x 1 dose
*Quinacrine
**> 8 years old: 100 mg TID x 7 days
**< 8 years old: 2 mg/kg TID x 7 days
*Nitazoxanide
**> 12 years old: 500 mg BID x 3 days
**4-11 years old: 200 mg BID x 3 days
**12-47 months old: 100 mg BID x 3 days

*Treatment is not always successful <ref>http://www.ncbi.nlm.nih.gov/pubmed/20086650 </ref>
*Strict adherence to handwashing (toileting, diaper changes, playing with pets, etc)
*Treat household members and/or sexual contacts if infected
*Treat asymptomatic infections in those at high-risk of transmitting to others (children in daycare, food handlers, etc) or those at risk of chronic symptoms
*Reinfection universal within 3 months in heavily infected endemic areas; treatment is not cost-effective in this setting

=Disposition=
*Disease is usually self-limited
*Admit those with systemic symptoms, severe dehydration, inability to tolerate PO fluids, or those with significant co-morbidities
*Supplementation with zinc and probiotics reduce severity/duration of diarrhea <ref>http://www.ncbi.nlm.nih.gov/pubmed/23192407</ref>

=References=
<references/>

Giardia lamblia

2014-09-29T17:06:01Z

Kldrake: new page

=Background=
*Flagellated protozoan
*Most common cause of parasitic diarrhea worldwide
*Transmitted by water contaminated with feces (human, beaver, muskrat, dogs, raccoons, etc)
*Common among campers and is also known as “backpacker’s diarrhea”
*Common in travelers to former Soviet Union, Caribbean, Latin America, India, Africa
*Infection rate is twice as high during summer months
*Also may be transmitted by contaminated food or close physical contact (sexual activity, daycare centers, etc)
*Patients with decreased gastric acidity, immunoglobulin deficiency, or immunocompromise are more susceptible
*Other names: “beaver fever”, “the Trotskys” (common in travelers to Leningrad) <ref>Marx, John A., Robert S. Hockberger, Ron M. Walls, James Adams, and Peter Rosen. "Chapter 94 -- Gastroenteritis." Rosen's Emergency Medicine Concepts and Clinical Practice. Philadelphia: Mosby/Elsevier, 2010. Print.</ref> <ref>Tintinalli, Judith E., and J. Stephan. Stapczynski. "Chapter 156 -- World Traveler." Tintinalli's Emergency Medicine: A Comprehensive Study Guide. New York: McGraw-Hill, 2011. Print.</ref> <ref>Tintinalli, Judith E., and J. Stephan. Stapczynski. "Chapter 154 -- Foodborne and Waterborne Diseases." Tintinalli's Emergency Medicine: A Comprehensive Study Guide. New York: McGraw-Hill, 2011. Print.</ref>

=Pathophysiology=
*Trophozoites infect duodenum, jejunum, and ileum where they form cysts
*Cysts are passed in feces; viable for long periods of time
*A single diarrheal stool may contain hundreds of millions of cysts or parasites

=Clinical Presentation=
*Often asymptomatic
*Most common symptoms include:
**Abdominal distension
**Colicky pain
**Flatulence
**Diarrhea (pale, loose, floating, foul odor)
**Borborygmi
*No blood or mucus in stool
*Sudden onset after incubation period of 1-3 weeks
*Symptoms usually resolve in 7-10 days
*85% of the time infection resolves spontaneously within 6 weeks
*May cause chronic malabsorption-like illness, especially in those with immunoglobulin deficiency
*Chronic infections cause weight loss, anemia, lactose intolerance

=Diagnosis=
*Normal WBC, no eosinophilia
*Stool O&P
**Motile trophozoites or cysts
**Able to diagnose infection readily in acute illness
**More difficult to diagnose in chronic or asymptomatic infection
*Antigen testing with ELISA, DFA, etc starting to replace microscopic examination with similar cost <ref>http://www.ncbi.nlm.nih.gov/pubmed/22632642</ref>
*Suspect protozoan illness in patients with diarrhea > 2 weeks

=Differential Diagnosis=
*Viral infection (e.g. rotavirus)
*Bacterial diarrhea
**Campylobacter
**Shigella
**Salmonella
**E. Coli
**E. Coli O157:H7
**Yersinia
**Vibrio cholera
**Clostridium difficile
*Parasitic infection
**Cryptosporidium
**Enteromonas hominis
**Entamoeba histolytica
*Toxin-mediated
**Staphylococcus aureus
**Bacillus cereus

=Management=
*Metronidazole
**Adult: 250 mg TID x 7-10 days
**Children: 5 mg/kg TID x 7 days (max dose 500 mg TID)
*Albendazole <ref>http://www.ncbi.nlm.nih.gov/pubmed/23235648</ref>
**400 mg PO daily x 5-10 days
*Tinidazole
**Adult: 2 grams PO x 1 dose
**Children: 50 mg/kg PO x 1 dose
*Quinacrine
**> 8 years old: 100 mg TID x 7 days
**< 8 years old: 2 mg/kg TID x 7 days
*Nitazoxanide
**> 12 years old: 500 mg BID x 3 days
**4-11 years old: 200 mg BID x 3 days
**12-47 months old: 100 mg BID x 3 days

*Treatment is not always successful <ref>http://www.ncbi.nlm.nih.gov/pubmed/20086650 </ref>
*Strict adherence to handwashing (toileting, diaper changes, playing with pets, etc)
*Treat household members and/or sexual contacts if infected
*Treat asymptomatic infections in those at high-risk of transmitting to others (children in daycare, food handlers, etc) or those at risk of chronic symptoms
*Reinfection universal within 3 months in heavily infected endemic areas; treatment is not cost-effective in this setting

=Disposition=
*Disease is usually self-limited
*Admit those with systemic symptoms, severe dehydration, inability to tolerate PO fluids, or those with significant co-morbidities
*Supplementation with zinc and probiotics reduce severity/duration of diarrhea <ref>http://www.ncbi.nlm.nih.gov/pubmed/23192407</ref>

=References=
<references/>

Helminth infections

2014-08-27T00:49:33Z

Kldrake: text for page

==Background==
*Approximately 2 billion people infected worldwide
*Many are WHO-designated Neglected Tropical Diseases
*At-risk populations include impoverished, children, immigrants, tourists, HIV/AIDS patients, refugees
*Most common in subtropical and tropical areas, moist climates, poor sanitation and hygiene

===Types:===
*Roundworm (Ascaris lumbricoides, Toxocara canis)
*Whipworm (Trichuris trichiura)
*Hookworm (Necator americanus, Ancylostoma duodenale)
*Tapeworm (Diphyllobothrium latum, Echinococcus granulosus)
*Cysticercosis (Taenia solium, Taenia saginata)
*Lymphatic filariasis (aka Elephantiasis; Wuchereria bancrofti, Brugia malayi, and Brugia timori)
*Dracunculiasis (aka Guinea Worm disease; Dracunculus medinensis)
*[[Onchocerciasis]] (aka River Blindness; Onchocerca volvulus)

===Transmission:===
*No direct person-to-person transmission

*Fecal-oral transmission (ingestion of eggs in contaminated soil / vegetables / water)
**Ascaris and whipworm from human feces
**Toxocara from dog / cat feces
**Echinococcus from sheep / cattle feces
**Taenia eggs from human feces

*Cutaneous transmission
**Hookworm eggs hatch in the soil, mature larvae penetrate skin
**Lymphatic filariasis transmitted via bite from infected mosquito (Anopheles, Aedes, and Culex)
**[[Onchocerciasis]] transmitted via bite from blackflies (Simulium species)

*Food or waterborne transmission
**Taenia also transmitted by ingestion of larval cysts in undercooked pork or beef
**Diphyllobothrium tapeworm transmitted by contaminated freshwater fish
**Dracunculiasis transmitted by ingestion of infected Cyclops water fleas in contaminated water (adult worm erodes through skin of leg, releases larvae in water when host wades in pond / open well, infecting the water fleas)

==History==
*Parasitic infections can be in the differential diagnosis for nearly every sign/symptom (GI, dermatologic, neurologic, pulmonary, ophthalmologic, hematologic)

*Obtain a travel history in every patient
**countries of travel
**duration of stay
**activities while traveling (adventure travel, tourism, working, swimming)
**living arrangements – city / village / hotel / tent
**drinking water source
**symptom chronology

==Clinical Features==
===Soil-transmitted helminths (Ascaris roundworm, whipworm, hookworm)===
*Morbidity is related to number of worms harbored in intestines
*Light infections often asymptomatic
*Heavier infections with variety of manifestations including GI symptoms (abdominal pain, diarrhea, blood in stool, rectal prolapse), malaise, weakness, impaired cognitive / physical development, malnutrition
*Hookworm and whipworm infestations also cause iron-deficiency anemia
**Adult worms attach to intestinal wall to feed, causing ongoing luminal blood loss
*Löffler’s syndrome
**Result of Ascaris or hookworm larval transit through the lungs
**Characterized by persistent non-productive cough, chest pain, wheezing, rales, pulmonary infiltrates on CXR and marked eosinophilia

===Toxocara canis===
*Visceral toxocariasis (visceral larva migrans)
**Larvae travel through liver / lungs / CNS causing fever, cough, enlarged liver, pneumonia
*Ocular toxocariasis (ocular larva migrans)
**Larvae travel to the eye causing inflammation and scarring of retina, usually only one eye, irreversible vision loss

===Tapeworm===
*Taenia (intestinal)
**Ingestion of eggs results in intestinal infection
**Usually asymptomatic, but heavier infections may result in GI upset, anemia, anorexia, diarrhea

*Diphyllobothrium
**Usually asymptomatic, may have GI symptoms
**Rarely, migrating proglottids can cause cholangitis, cholecystitis, or intestinal obstruction
**Competes for absorption of vitamin B12, causes pernicious anemia

===Echinococcosis===
*Larvae travel from small intestine via bloodstream to multiple sites
*Liver is target organ in ⅔ of cases
*Less than 10% of patients have brain involvement (seizures, focal neurologic signs)
*Pulmonary involvement also possible (cough, expectoration of sand-like material, hemoptysis, chest pain, anaphylactoid reaction from leaking cyst, mass effect from expanding cyst)

===Cysticercosis (Taenia larval cysts)===
*Adult worm matures in intestine, may end up anywhere in body (CNS, muscle, soft tissue, eye, heart, liver)
*Cluster of larvae in the brain forms expanding cyst
*Neurologic symptoms including seizures, AMS, focal neurologic deficit, or hydrocephalus

===Lymphatic filiariasis===
*Larvae migrate to lymphatic vessels and mature into adults
*Massive peripheral edema with thickening of overlying skin particularly in lower extremities and genitalia
*Recurrent cellulitis is common

===Dracunculiasis===
*Adult worm migrates through subcutaneous tissues of the leg and erodes through skin
*Rash, intense pruritus, nausea, vomiting, dyspnea, and diarrhea prior to eruption

==Diagnosis==
===General===
*Stool studies (ova and parasites)
*CBC to identify peripheral eosinophilia or anemia (not sensitive or specific)
*Peripheral blood smear to identify microfilariae (e.g. lymphatic filariasis)

===Disease/Symptom Specific===
*Pulmonary symptoms: CXR and sputum smear (e.g. Löffler’s syndrome)
*CNS symptoms
**Neuroimaging (CT with contrast or MR brain) may reveal ring-enhancing lesions, calcifications, or focal enhancing lesions in neurocysticercosis
**CSF serologies/ELISA for echinococcus, cysticercosis
*Ultrasound or CT can localize cyst of echinococcus
*ELISA or biopsy of affected tissue to diagnosis toxocariasis, cysticercosis
*Identification of adult worm or microscopic larvae in cutaneous ulcer fluid can confirm dracunculiasis

===Proposed Diagnostic Criteria for Cysticercosis===
#1 Definitive diagnosis requires 1 absolute criterion, or 2 major plus 1 minor and 1 epidemiologic criteria.
#2 Probable diagnosis requires 1 major plus 2 minor criteria, or 1 major plus 1 minor plus 1 epidemiologic criteria, or 3 minor plus 1 epidemiologic criteria.

*Absolute
**Demonstration of parasite from biopsy
**Cystic lesion with scolex on neuroimaging
**Direct visualization of parasites on fundoscopic exam

*Major
**Lesions highly suggestive of neurocysticercosis on imaging
**Positive ELISA for anticysticercal antibodies
**Resolution of intracranial lesions after antihelminthic therapy
**Spontaneous resolution of single enhancing lesions

*Minor
**Lesions compatible with neurocysticercosis on imaging
**Clinical symptoms suggestive of neurocysticercosis
**Positive ELISA for antibodies in CSF
**Cysticercosis outside of the nervous system

*Epidemiologic
**Recent travel to endemic area
**Residence in endemic area
**Household contact with Taenia solium infection

==Clinical Management==
===Soil-transmitted helminthes===
*Ascaris: albendazole 400 mg x 1 dose OR mebendazole 100 mg BID x 3 days (both high efficacy)

*Whipworm (Trichuris): albendazole 400 mg x 1 dose
**Historically treated with albendazole or mebendazole, but monotherapy has low efficacy against Trichuris especially in heavy infections; higher cure rate achieved with oxantel pamoate-albendazole combination compared to any monotherapy in recent RCT (Speich, et al. NEJM 2014; 370:610-620)

*Hookworm: albendazole 400 mg x 1 dose (high efficacy) OR mebendazole 500 mg x 1 dose (low to moderate efficacy)

*Iron supplements in anemia

===Toxocariasis (visceral larva migrans)===
*Diethylcarbamazine 6 mg/kg/day divided TID x 7-10 days OR mebendazole 100-200 mg BID x 5 days OR albendazole 400 mg BID x 3-5 days

===Tapeworm===
*Diphyllobothrium
**Praziquantel 5-10 mg/kg x 1 dose
**Replete vitamin B12 if patient has megaloblastic anemia

*Echinococcus:
**Tissue stage/hydatid disease: albendazole 400 mg BID x 28 days, repeat as needed every 2 weeks x 3 cycles
**Do not aspirate cysts (risk of seeding disease or anaphylactoid reaction from spillage of hydatid sand which contains antigenic proteins)
**Surgical resection of cysts

===Cysticercosis (Taenia)===
*Neurocysticercosis
**Antiepileptic therapy is first-line treatment
**Treat active disease with caution. Antihelminthic therapy may cause increased inflammation, leading to further tissue damage especially with ocular or spinal involvement
**Ophthalmologic exam before treatment
**Steroids before antihelminthic therapy
**Albendazole 400 mg BID x 8-30 days
**Neurosurgery consult for symptomatic disease (acute obstructive hydrocephalus may occur)

*Intestinal stage
**Praziquantel 5-10 mg/kg x 1 dose

===Lymphatic filariasis===
*Diethylcarbamazine:
**Day 1: 50 mg PO
**Day 2: 50 mg TID
**Day 3: 100 mg TID
**Days 4-21: 6 mg/kg/day divided TID
*Combined treatment with diethylcarbamazine/albendazole or ivermectin/albendazole may be more effective
*Meticulous skin care to prevent superinfection/cellulitis
*Surgical management of scrotal elephantiasis and chronic lymphatic obstruction

===Dracunculiasis===
*Metronidazole 750 mg TID x 5-10 days OR thiabendazole 50-75 mg/day divided BID x 3 days
*Must also extract adult worm from skin
*Patients with active skin lesions should stay out of potable water

==See Also==

==External Links==

==Sources==
# "Chapter 133 - Parasitic Infections." Rosen's Emergency Medicine: Concepts and Clinical Practice. Ed. John A. Marx, Robert S. Hockberger, and Ron M. Walls. Philadelphia, PA: Mosby Elsevier, 2014. 1768-784.
# "The 17 Neglected Tropical Diseases." World Health Organization. http://www.who.int/neglected_diseases/diseases/en/. Web. 11 Aug. 2014.
# "Parasites." Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/. Web. 11 Aug. 2014.
# Wilcox S, Thomas S, Brown D, Nadel E. “Gastrointestinal Parasite.” The Journal of Emergency Medicine, 2007; 33(3):277-280
# Del Brutto OH, Rajshekhar V, White A, et al. “Proposed diagnostic criteria for neurocysticercosis.” Neurology, 2001; 57:177-183.
# Del Brutto OH. “Diagnostic criteria for neurocysticercosis, revisited.” Pathogens and Global Health, 2012; 106(5):299-304.
# Speich B, Ame S, et al. "Oxantel Pamoate–Albendazole for Trichuris Trichiura Infection." New England Journal of Medicine, 2014; 370: 610-620.
<references/>

[[Category:ID]]