Travel medicine
Fever
- get incubation period- if > 1mo, dengue, rickettsia, viral hem fvr less likely
- cbc c diff, thick smear, lft, ua, blood/ stool cx, cxr, serologies for specific viruses
Malaria
- most imp cause of fvr
- plasmodium falciparum can be rapidly fatal and needs to be ruled out soon
- p falciparum from sub Saharan Africa, 90% of pt have sx within 1 mo of return
- p vivax- Asia and Latin, 50% pt have sx within 1 mo- 2% up to 1 yr out
- chemoprophylaxsis does not guarantee protection
- usually have fvr, but 10- 40% may not
- fvr q 48- 72 hr pathognomic of vivax, ovale, malariae infc
- can also have ha, cough, gi sx
- check thick smear initially and if neg, repeat in 12- 24 hrs
- thrombocytopenia and splenomegaly common
- p falciparum unpredictable- admit and monitor for hypoglycemia
- iv meds if renal, resp failure, ams, sx, shock, anemia, p falcip rbc load >4% in nonimmune pt
Dengue
- aedes mosquito in urban area
- incubate for 4- 7d, influenza like prodrome, fvr, ha, myalgia, LN, rash
- dengue shock syndrome and hem fvr rare in travelers- usually in pt c prev infc
- leukopenia, thrombocytopenia
- dx by 4x increase in acute/ conv titres
Rickettsia/ Typhus
- fvr, ha, myalgia
- xmitted by arthropods/ ticks
- painless eschar at inoculation site imp clue
- camping, hiking in grassy/ scrub area
- regional LN, rash, leukopenia, thrombocytopenia
- dx clinically
- tx c tetracycline
- confirm serologically
Leptospirosis
- fvr, myalgia, ha, rash
- conjuntival suffusion characteristic but not common
- exp to fresh water while rafting, kayaking
- biphasic illness with meningitis, uveitis, transminitis, proteinuria, hematuria
- tx c pcn or tetra
- confirm by serology
Typhoid Fever
- fvr, ha
- visiting friends in India, Phillipines Latin
- abd pain, constipation, -diarrhea rare
- leukopenia, thrombocytopenia, dry cough, LN
- insidious onset unlike dengue or rickettsia
- dx by blood cx for salmonella enterica serotype typhi
- serology unreliable
- tx empirically with flouroquinolone or 3rd gen cephal
- vaccine partially effecive and breakthrough infc possible
Hemorrhagic Fever
- meningococcemia, malaria, leptospirosis, rickettsia- all treatable with abx
- also untreatable viruses- dengue, yellow fvr- but hem forms rarely seen in travelers
- also consider Ebola and Lassa fever- public health hazard
- h/o visit to rural area or contact with ill people in endemic area
- usually 3 wk after exposure
CNS Changes and Fever
- malaria, tb, typhoid fvr, rickettsia, poliomyelitis, rabies, viral (Japanese/ West Nile/ tick borne) encephalitis
- meningococcal meningitis assoc with Haj to Mecca
- eosinophilic meningitis assoc c coccidiomycosis or angiostrongyliasis- rat lung worm to brain
- trypanosomiasis by tsetse fly- Africal sleeping sickness- red chancre at site of fly bite, fvr, ha, myalgia going to meningoencephalitis. May see trypansosomes in smear in acute phase
Resp Sx and Fever
- consider strep pneumonia, influenza, mycoplasma, legionella, tb
- Q Fever- coxiella burnetti- fvr, pna, hepatitis and animal exposure
- Lofflers syn- pulm infiltrates, eosinophilia from transient migration of larval helminthes through lungs
- Cough also seen in malaria, typhoid fvr, scrub typhus, dengue
Sex/ Blood Exposure and Fever
- can have fvr without genital findings- hiv, syphilis (treponema pallidum) cmv, ebv, hep B
- also from tattoo, piercing, share razor, blood xfsn
Eosinophilic Fever
- >400 per cubic mm
- due to blood CA or allergy or helminthic infc
- hookworm, ascariasis, strongyloides, schistosomiasis, filariasis, visceral larva migrans, trichinosis, cocci
- eval with stool for O&P
- serology
- blood smear
- skin snips for microfilariae
Diarrhea
- most respond to antibiotics or antimotility agents
- as duration of diarrhea increases, higher chance of parasitic cause
- giardia, cryptosporidiosis, entamoeba, cyclospora
- 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
- tx regular travelers diarrhea with fluids, antimotility agents, abx- fluoro or macrolide
- tx invasive enteropathy- bloody/ fvr- same but no antimotility agents
- if bloody stool but no fvr, consider enterhemorrhagic E coli- do not give abx since will get hemolytic uremic syndrome in kids
- examine stool if diarrhea invasive, persistent, unresponsive to standard tx or immune compromised
- if persistent diarrhea, give empiric flouro or macrolide or consid metronidazole for giardia- most common parasite
- try lactose free diet
- chronic diarrhea usually self limited within 1 yr
Skin Conditions
Papules
- insect bites- cluster or linear distribution
- scabies- if sex active or backpacker
- seabathers eruption- confined to skin covered by swim suit- jellyfish larvae trapped under cloth
- cercarial dermatitis- skin exposed to freshwater schistosomes or coastal water clam diggers itch
Sub Q Swelling and Nodules
- myasis- skin invaded by fly larvae- like boil but with central opening in which larvae may hide
- tungiasis
- loa loa
- trypanosomiasis
Ulcers
- pyoderma/ ecthyma- secondary staph cellulitits post bite
- leishmaniasis
- mycobacterium marinum
Linear and Migratory Lesions
- cutaneous larvae migrans- by soil contact with dog/ cat feces
- photodermatitis
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Mistry