TRAVEL MEDICINE/NUTRITION
From the 21st Annual Family Medicine Today, sponsored by the HealthPartners Institute for Medical Education,
Minneapolis, MN
| MEDICAL PROBLEMS IN RETURNING TRAVELERS —Patricia Walker, MD, Medical Director, Center for International
Health, St. Paul, MN
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| Introduction: <1% of deaths of travelers due to tropical infectious disease; higher likelihood of injury when traveling
to less developed countries; for every 100,000 travelers to developing country, 8000 require visit to physician, 50 require
air evacuation (discuss evacuation insurance with traveling patients), and 1 dies; study showed ≈64% of travelers
developed illness (diarrhea most common); in 27% to 42% of cases, fever due to malaria (cause unknown ≈25% of
time)
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| Demographics of ill travelers: older travelers with long complex itineraries; most patients present within 1 mo of
travel; 15% of patients visiting friends and relatives; immigrants returning home (eg, Kenya, Southeast Asia)
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| Risk factors: 30% to 50% of patients who stay in less developed country >1 mo develop diarrhea, 2% develop malaria;
longer length of stay; younger age; living with local populations; sleeping in tents; traveling with chronic illness;
visiting West Africa associated with highest incidence of malaria imported to United States; working internationally
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| Injury prevention: avoid motorcycles; use seat belts; avoid riding in small airplanes; avoid traveling at night; travel
in groups
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| Patient history: ask, when did you go? consider whether incubation period (first or second day after arrival at destination
through day patient leaves, to time patient presents with symptoms) longer or shorter than 3 wk; exactly where
did you go? (eg, large city, countryside); consider exposures; did you see someone specializing in travel medicine
before you left? did you get hepatitis A or B or typhoid vaccines?
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| Fever patterns: patients usually present within 1 to 2 days of start of fever and may not yet have developed pattern;
patients may present initially with other symptoms (eg, joint pain, rash); typhoid fever—continuous; body temperature
38ºC to 39ºC until antibiotics started; malaria—fever caused by Plasmodium falciparum mosquito higher and
more erratic than malaria caused by Plasmodium vivax mosquito (fever every first and third day); tuberculosis
(TB)—remittent; persistent low-grade fever with pulmonary TB; Borrelia—classic high fever at beginning; recurrent
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| Incubation periods: <21 days—traveler’s diarrhea; dengue fever; malaria; typhoid fever; >21 days—viral hepatitis
(hepatitis E); immigrant traveler with history of malaria may present later; tropical infectious diseases (caused by
eg, Strongyloides) can last many years
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| Exposures: mosquito and tick bites; swimming in fresh water; walking through long grass; food (eg, untreated water,
unpasteurized dairy products [consider Brucella in patients with fever and joint pain; advise patients about goat
cheeses in Europe]); rickettsial diseases (eg, Crimean-Congo hemorrhagic fever [CCHF] from tick bites); African trypanosomiasis
caused by tsetse fly in East Africa; walking on beach barefoot; sexual contacts; contact with infected
persons
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| Cutaneous manifestations: cutaneous larva migrans—associated with travel to Mexico; itchy serpiginous lesions
develop 2 to 3 wk after returning to United States; tick or scrub typhus—rash or eschar (can be subtle, eg, in armpit,
along waistline, groin area); Australian tick typhus—papulovesicular rash for 3 days; fever; headache; painless lesion
can develop after removing tick; check patient’s hair; look for eschar; acute schistosomiasis—associated with travel
to Dominican Republic; 2 wk after returning to United States, patients develop high fever, cough, urticarial rash, high
white blood cell count, and marked eosinophilia; schistosomes enter skin during freshwater swimming; patient develops
hives as larvae migrate; serologies not yet positive; treat with praziquantel for 1 day
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| Dengue fever: signs and symptoms—fever; severe myalgia; abdominal pain; headache; diffuse blanching; maculopapular
rash; petechiae; diarrhea; weight loss; retroorbital pain; thrombocytopenia; may have mild hemorrhagic component;
cases from Mexico, Caribbean, Central and South America, Africa, Southeast Asia, and Indonesia; “dengue, downtown,
daytime” (urban day-biting mosquito adapted to living in water jars used for collecting rainwater); 100 million cases per
year; low fatality (mostly in children with dengue hemorrhagic fever); second most common cause of identified fever in
returning traveler; 4 serotypes; short incubation period; also known as “break bone fever” due to myalgias and headache;
symptoms resolve after ≈1 wk; rash—fine and reddish; slightly erythematous with blanching; patients can develop hepatic
dysfunction; lifelong immunity serotype specific; dengue hemorrhagic fever occurs only in previously infected patients;
mortality >10% if patient develops shock; treatment supportive
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| Viral hepatitis: hepatitis E and A most common in travelers; consider malaria in patients who present with fever and jaundice
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| Typhoid fever: 21 million cases per year worldwide; most common in India, Southeast Asia, and Indonesia; injectable
vaccine efficacious for 2 yr (oral for 5 yr); incubation period usually <3 wk; signs and symptoms—sustained or
remittent fever; headache; malaise; anorexia; abdominal pain; diarrhea followed by constipation; relative bradycardia;
hepatosplenomegaly; diagnosed by culture; resistant to chloramphenicol, amoxicillin, and trimethoprim-sulfamethoxazole
(eg, Bactrim, Septra); 24% of cases in United States resistant to one drug, 17% resistant to >1 drug; ciprofloxacin
no longer used as prophylaxis for traveler’s diarrhea from India and Southeast Asia, due to Campylobacter
resistance (use azithromycin); Centers for Disease Control and Prevention (CDC) recommends giving vaccine to those
traveling >3 wk (use clinical judgment)
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| Malaria: 500 million cases per year worldwide; 1 million deaths per year (90% in children <5 yr of age); highest incidence
in Africa; present in Mexico; studies show low awareness of risk and low compliance with prophylaxis;
chemoprophylaxis—antimalarial agent must be taken after returning home (mefloquine [Lariam] for 1 mo, atovaquone
and proguanil [Malarone] for 1 wk); medications must be continued after leaving area of exposure; use chloroquine
if no resistance; otherwise, use mefloquine (incidence of neuropsychiatric side effects, 1%-3%); if patient has
seizure disorder or history of depression, use Malarone or doxycycline; Malarone 99% efficacious in prevention of
malaria (start 1 day before travel and take daily until 1 wk after returning; $4-$5 per tablet); deaths—5% due to delay
in seeking care; most due to missed diagnosis; ≈33% occur in US travelers, 17% in visiting friends or relatives, refugees,
and immigrants; most fatal cases in patients who traveled to Africa, Indonesia, or Southeast Asia; prevention—
3M Ultrathon and Sawyer insect repellents (formulated with DEET) recommended (last 10-12 hr; apply 20 min after
applying sunscreen in morning and reapply at night); if patient presents with condition that looks like influenza or viral
syndrome, obtain 3 stool specimens before ruling out malaria; highly sensitive and specific rapid serologic testing
available
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| Summary: ask about exact itinerary and dates; calculate incubation period; ask detailed questions about preparations
and medications taken overseas; initial laboratory evaluation—complete blood cell count (CBC) with differential;
electrolytes; liver function tests (LFTs); cultures; stool testing for malaria; serologic studies for dengue fever; spin
and save serum
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| Case: man, 51 yr of age, traveled to northern Thailand; went on elephant trek, rafted down river to local tribal villages
(fell into river), and slept in villages; returned home asymptomatic; within 1 wk, admitted to hospital with high fever,
headache, diffuse truncal rash, and eschar on left shoulder; patient became critically ill (eg, meningoencephalitis,
coma, acute hepatic and renal failure); after 2-mo hospitalization, patient discharged to rehabilitation with hearing
loss, ataxia, cognitive deficits, and diagnosis of multisystem failure presumed infectious, etiology indeterminate;
diagnosis—scrub typhus (Rickettsia tsutsugamushi); transmitted through chigger bites while walking through long
grass (advise travelers to wear long pants tucked into boots and use insect repellent); initial treatment doxycycline
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| NUTRITIONAL SUPPORT OF SERIOUSLY ILL PATIENTS —David J. Dries, MD, John F. Perry Jr. Professor of
Surgery, University of Minnesota Medical School, and Assistant Medical Director for Surgical Care, HealthPartners
Medical Group, Minneapolis, MN
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| Introduction: response to nutrition products differs based on whether patient in high-grade inflammatory state or relatively
quiescent state (eg, nutrition product with additives that suppress inflammation may increase risk for infectious
complications); consistent clinical strategies for use of products unclear
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| Malnourished patient: >10% loss of ideal body weight; check hepatic secretory proteins (albumin and prealbumin);
serial measurements of albumin do not necessarily reflect deterioration or improvement, unless measured over time;
half-life of prealbumin 8 days; look at body characteristics (anthropometry); perform cellular immunity studies; check
muscle function
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| General feeding principles: 25 Kcal/kg per day (30%-70% glucose, 15%-30% fat, 15%-20% protein; enteral feeding
formulas available in appropriate ratios); supplemental protein may be recommended for patients with inflammation
or critical or ongoing serious illness, to preserve muscle mass
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| Feeding routes: tube-feeding through gut—nasogastric (NG) tube into stomach or small bowel; some studies show
increase in reflux and higher incidence of pneumonia when feeding into stomach; no difference in outcome; small
bowel used in absence of bowel sounds; small bowel functional through surgical procedures; when feeding through
stomach, check residual volume (if >150 mL, reduce feeding, stop for 2 hr, and start again); in patients with pancreatitis,
insert feeding tube into proximal jejunum; enteral feedings give gut higher osmotic load than with normal eating
(diarrhea reflection of product, but if patient has history of antibiotic use, check for Clostridium difficile); intravenous
(IV) nutrition—more expensive; may be associated with increased risk for infectious complications and complications
with central venous access
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| Monitoring: overfeeding; exhaled gas analysis (respiratory quotient [ratio of exhaled CO2 to consumed O2 ] >1 suggests
overfeeding); serum urea nitrogen (BUN) >100 mg/dL suggests protein overload; patients with acute renal failure
should be fed aggressively; patients given medications or dialyzed acutely to help maintain metabolic needs;
control triglycerides; watch propofol (higher levels increase fat load and should be taken into account when considering
nutrition needs); assess visceral proteins, prealbumin and albumin weekly; check fluid and electrolyte status 2 to 3
times per week; check LFTs
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| Special patient groups: chronic renal failure—account for loss of protein, depending on whether patient undergoing
peritoneal dialysis or intermittent hemodialysis; reduce protein; acute renal failure—eg, patient with postoperative
complication or patient in intensive care unit (ICU) with pneumonia and acute renal insufficiency; do not reduce
acute protein support; feed aggressively; if short-term dialysis needed, better to dialyze to manage metabolically than
to undersupport patient with nutrition; cirrhosis with hepatic failure—hypermetabolic state with increased loss of
protein, ascites, and electrolyte shifts; some data suggest emphasizing products with branched-chain amino acids for
protein support (in cirrhotic patients, if ammonia level increasing, or patient has other signs of worsening hepatic insufficiency,
consider switching to more expensive branched-chain formulations); respiratory failure—patients may
need less fat and carbohydrate (enteral products usually in reasonable ratios); ask dietitian to add more protein to enteral
feeding mix and reduce net rate of feeding; obesity—consider ideal body weight; high-risk patients due to severe
malnutrition—body mass index (BMI) ≤16; give carbohydrates to patients who had been carbohydrate-poor for
extended time; insulin spike and sudden shifts of potassium, magnesium, and phosphorus from vascular bed into cells
can lead to ramifications in muscle function, cardiovascular and respiratory collapse, and cardiac arrhythmias; reduce
initial feeding prescription by 50% for 7 to 10 days
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| Nosocomial infections: recent study looked at nutritional support of patients in ICU and American College of Chest
Physicians (ACCP) guidelines; patients who reached ≥25% of caloric goal had decreased risk for infection; risk for infection
increases in patients severely below caloric provision; moderate amount of nutrition in patients probably sufficient
for decreasing risk for infectious complications
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| Hyperglycemia: use of mechanical ventilation reduced by controlling serum glucose in cardiovascular surgery patients,
some trauma patients, and patients with myocardial infarction; benefits not as clear in general critical care population
or seriously ill population; immune adjuncts—eg, arginine, omega-3 fatty acids, nucleotides; likely not
needed; recent consensus statement suggests avoiding use in patients with elevated acute physiological assessment
and chronic health evaluation (APACHE) score; difficult to determine where products fit in (based on patient’s physiologic
state; use in more seriously ill patients not recommended); avoid hyperglycemia; patient’s calorie goal reached
more rapidly and safely with IV nutrition than with gut nutrition (consider costs, complications, and risk for infection)
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| Gut vs IV feeding: enteral (gut) feeding—early feeding (within 36 hr of hospitalization or surgery) likely to reduce
length of hospital stay and risk for infectious complications; IV feeding—with careful serum glucose control, feeding
via either route likely successful; despite risks for infectious complications associated with central lines, mechanical
complications associated with line placement (5% risk; eg, pneumothorax), and additional costs, IV feeding can be as
safe as gut feeding; using gut preferred; when considering infectious complications, immune-enhancing products and
feeding through gut may be beneficial, but no difference in mortality; specific applications of specialized products unclear
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| Postoperative patients: few problems with feeding patients early after procedures; alert patients can start to eat; incidence
of complications increases if postoperative nutrients delayed
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| Complications: wound or other infections; breakdown of anastomosis or suture line; data support aggressive approach
to feeding (by mouth if patient capable); NG tube intubation—for every 20 patients with postoperative NG
tube placement, only one required; meta-analysis suggests NG tubes not needed after contemporary abdominal surgical
procedures; recommended only as therapeutic approach; useful in patients with bowel obstruction, but appears to
slow passage of feces; vomiting—gum chewing in early postoperative period may be helpful; consider liquid diet, ondansetron
(Zofran), steroids, droperidol, and propofol in critically ill patients; IV anesthetic techniques; some agents
more expensive than others
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Suggested Reading
Apfel CC et al: A factorial trial of six interventions for th.prevention of postoperative nausea and vomiting. N Engl J
Med 350:2441, 2004; Bistrian BR et al: Nutritional and metabolic support in the adult intensive care unit: key controversies.
Crit Care Med 34:1525, 2006; Cerra FB et al: Applied nutrition in ICU patients. A consensus statement
of the American College of Chest Physicians. Chest 111:769, 1997; Freedman DO et al: Spectrum of disease and relation
to place of exposure among ill returned travelers. N Engl J Med 354:119, 2006; Hill DR: Health problems in a
large cohort of Americans traveling to developing countries. J Travel Med 7:259, 2000; Laver SM et al: Knowledge
of malaria, risk perception, and compliance with prophylaxis and personal and environmental preventive measures in
travelers exiting Zimbabwe from Harare and Victoria Falls International airport. J Travel Med 8:298, 2001; Lewis SJ
et al: Early enteral feeding versus "nil by mouth" after gastrointestinal surgery: systematic review and meta-analysis of
controlled trials. BMJ 323:773, 2001; Lobel HO et al: Use of prophylaxis for malaria by American travelers to Africa
and Haiti. JAMA 257:2626, 1987; Newman RD et al: Malaria-related deaths among U.S. travelers, 1963-2001. Ann
Intern Med 141:547, 2004; Peter JV et al: A metaanalysis of treatment outcomes of early enteral versus early
parenteral nutrition in hospitalized patients. Crit Care Med 33:213, 2005; Rubinson L et al: Low caloric intake is associated
with nosocomial bloodstream infections in patients in the medical intensive care unit. Crit Care Med 32:350,
2004; Steinberg EB et al: Typhoid fever in travelers: who should be targeted for prevention? Clin Infect Dis 39:186,
2004; Suh KN et al: Evaluation of fever in the returned traveler. Med Clin North Am 83:997, 1999; Vermeulen H
et al: Nasogastric intubation after abdominal surgery: a meta-analysis of recent literature. Arch Surg 141:307, 2006.
Educational Objectives
| The goals of this program are to help identify and improve management of infectious diseases in returning travelers
and to improve nutritional support in critically ill patients. After hearing and assimilating this program, the participant
will be better able to:
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 | 1. Discuss risks and exposures to traveling patients.
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| 2. Evaluate fever patterns and incubation periods to determine causes of illness.
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| 3. Describe common causes of fever in travelers, such as dengue fever, typhoid fever, and malaria.
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| 4. Monitor and provide sufficient nutritional support in seriously ill patients.
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| 5. Choose between enteral and intravenous feeding based on patients’ risks and prognoses.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty members to disclose relevant
financial relationships within the past 12 months that might create any personal conflicts of interest. Any identified
conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business
or commercial interest. For this program, the faculty reported nothing to disclose.
Acknowledgements
Drs. Walker and Dries spoke in Minneapolis, MN, at the 21st Annual Family Medicine Today, presented March 8-9,
2007, by HealthPartners Institute for Medical Education. The Audio-Digest Foundation thanks the speakers and the
HealthPartners Institute for Medical Education for their cooperation in the production of this program.
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