Chapter 117. Health Advice for International Travel (Part 7)

Gastrointestinal Illness Decreased levels of gastric acid, abnormal gastrointestinal mucosal immunity, other complications of HIV infection, and medications taken by HIVinfected patients make travelers diarrhea especially problematic in these individuals. Travelers diarrhea is likely to occur more frequently, be more severe, be accompanied by bacteremia, and be more difficult to treat. Although uncommon, Cryptosporidium, Isospora belli, and Microsporidium infections are associated with increased morbidity and mortality in AIDS patients.The HIV-infected traveler must be careful to consume only appropriately prepared foods and beverages and may benefit from antibiotic prophylaxis fortravelers diarrhea. Sulfonamides (as used to prevent pneumocystosis) are ineffective because...
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Chapter 117. Health Advice for International Travel (Part 7) Chapter 117. Health Advice for International Travel (Part 7) Gastrointestinal Illness Decreased levels of gastric acid, abnormal gastrointestinal mucosalimmunity, other complications of HIV infection, and medications taken by HIV-infected patients make travelers diarrhea especially problematic in theseindividuals. Travelers diarrhea is likely to occur more frequently, be more severe,be accompanied by bacteremia, and be more difficult to treat. Althoughuncommon, Cryptosporidium, Isospora belli, and Microsporidium infections areassociated with increased morbidity and mortality in AIDS patients. The HIV-infected traveler must be careful to consume only appropriatelyprepared foods and beverages and may benefit from antibiotic prophylaxis fortravelers diarrhea. Sulfonamides (as used to prevent pneumocystosis) areineffective because of widespread resistance. Other Travel-Related Infections Data are lacking on the severity of many vector-borne diseases in HIV-infected individuals. Malaria is especially severe in asplenic persons and in thosewith AIDS. The HIV load doubles during malaria, with subsidence in ~8–9 weeks;the significance of this increase in viral load is unknown. Visceral leishmaniasis (Chap. 205) has been reported in numerous HIV-infected travelers. Diagnosis may be difficult, given that splenomegaly andhyperglobulinemia are often lacking and serologic results are frequently negative.Sandfly bites may be prevented by evening use of insect repellents. Certain respiratory illnesses, such as histoplasmosis andcoccidioidomycosis, cause greater morbidity and mortality among patients withAIDS. Although tuberculosis is common among HIV-infected persons (especiallyin developing countries), its acquisition by the short-term HIV-infected travelerhas not been reported as a major problem. Medications Adverse events due to medications and drug interactions are common andraise complex issues for HIV-infected persons. Rates of cutaneous reaction (e.g.,increased cutaneous sensitivity to sulfonamides) are unusually high amongpatients with AIDS. Since zidovudine is metabolized by hepatic glucuronidation,inhibitors of this process may elevate serum levels of the drug. Concomitantadministration of the antimalarial drug mefloquine and the antiretroviral agentritonavir may result in decreased plasma levels of ritonavir. In contrast, nosignificant influence of concomitant mefloquine administration on plasma levelsof indinavir or nelfinavir was detected in two HIV-infected travelers. There is astrong theoretical concern that the antimalarial drugs lumefantrine (combined withartemisinin in Coartem and Riamet) and halofantrine may interact with HIVprotease inhibitors and nonnucleoside reverse transcriptase inhibitors since thelatter are known to be potent inhibitors of cytochrome P450. Chronic Illness, Disability, and Travel Chronic health problems need not prevent travel, but special measures canmake the journey safer and more comfortable. Heart Disease Cardiovascular events are the main cause of deaths among travelers and ofin-flight emergencies on commercial aircraft. Extra supplies of all medicationsshould be kept in carry-on luggage, along with a copy of a recentelectrocardiogram and the name and telephone number of the travelers physicianat home. Pacemakers are not affected by airport security devices, althoughelectronic telephone checks of pacemaker function cannot be transmitted byinternational satellites. Travelers with electronic defibrillators should carry a noteto that effect and ask for hand screening. A traveler may benefit fromsupplemental oxygen; since oxygen delivery systems are not standard,supplementary oxygen should be ordered by the travelers physician well beforeflight time. Travelers may benefit from aisle seating and should walk, performstretching and flexing exercises, consider wearing support hose, and remainhydrated during the flight to prevent venous thrombosis and pulmonary embolism. Chronic Lung Disease Chronic obstructive pulmonary disease is one of the most commondiagnoses in patients who require emergency-department evaluation for symptomsoccurring during airline flights. The best predictor of the development of in-flightproblems is the sea-level PaO2. A PaO2 of at least 72 mmHg corresponds to an in-flight arterial PaO2 of ~55 mmHg when the cabin is pressurized to 2500 m (8000ft). If the travelers baseline Pa O2 is