Travel medicine

Fever

1. get incubation period- if > 1mo, dengue, rickettsia, viral hem fvr less likely
2. cbc c diff, thick smear, lft, ua, blood/ stool cx, cxr, serologies for specific viruses

Malaria

1. most imp cause of fvr
2. plasmodium falciparum can be rapidly fatal and needs to be ruled out soon
3. p falciparum from sub Saharan Africa, 90% of pt have sx within 1 mo of return
4. p vivax- Asia and Latin, 50% pt have sx within 1 mo- 2% up to 1 yr out
5. chemoprophylaxsis does not guarantee protection
6. usually have fvr, but 10- 40% may not
7. fvr q 48- 72 hr pathognomic of vivax, ovale, malariae infc
8. can also have ha, cough, gi sx
9. check thick smear initially and if neg, repeat in 12- 24 hrs
10. thrombocytopenia and splenomegaly common
11. p falciparum unpredictable- admit and monitor for hypoglycemia
12. iv meds if renal, resp failure, ams, sx, shock, anemia, p falcip rbc load >4% in nonimmune pt

Dengue

1. aedes mosquito in urban area
2. incubate for 4- 7d, influenza like prodrome, fvr, ha, myalgia, LN, rash
3. dengue shock syndrome and hem fvr rare in travelers- usually in pt c prev infc
4. leukopenia, thrombocytopenia
5. dx by 4x increase in acute/ conv titres

Rickettsia/ Typhus

1. fvr, ha, myalgia
2. xmitted by arthropods/ ticks
3. painless eschar at inoculation site imp clue
4. camping, hiking in grassy/ scrub area
5. regional LN, rash, leukopenia, thrombocytopenia
6. dx clinically
7. tx c tetracycline
8. confirm serologically

Leptospirosis

1. fvr, myalgia, ha, rash
2. conjuntival suffusion characteristic but not common
3. exp to fresh water while rafting, kayaking
4. biphasic illness with meningitis, uveitis, transminitis, proteinuria, hematuria
5. tx c pcn or tetra
6. confirm by serology

Typhoid Fever

1. fvr, ha
2. visiting friends in India, Phillipines Latin
3. abd pain, constipation, -diarrhea rare
4. leukopenia, thrombocytopenia, dry cough, LN
5. insidious onset unlike dengue or rickettsia
6. dx by blood cx for salmonella enterica serotype typhi
7. serology unreliable
8. tx empirically with flouroquinolone or 3rd gen cephal
9. vaccine partially effecive and breakthrough infc possible

Hemorrhagic Fever

1. meningococcemia, malaria, leptospirosis, rickettsia- all treatable with abx
2. also untreatable viruses- dengue, yellow fvr- but hem forms rarely seen in travelers
3. also consider Ebola and Lassa fever- public health hazard
4. h/o visit to rural area or contact with ill people in endemic area
5. usually 3 wk after exposure

CNS Changes and Fever

1. malaria, tb, typhoid fvr, rickettsia, poliomyelitis, rabies, viral (Japanese/ West Nile/ tick borne) encephalitis
2. meningococcal meningitis assoc with Haj to Mecca
3. eosinophilic meningitis assoc c coccidiomycosis or angiostrongyliasis- rat lung worm to brain
4. 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

1. consider strep pneumonia, influenza, mycoplasma, legionella, tb
2. Q Fever- coxiella burnetti- fvr, pna, hepatitis and animal exposure
3. Lofflers syn- pulm infiltrates, eosinophilia from transient migration of larval helminthes through lungs
4. Cough also seen in malaria, typhoid fvr, scrub typhus, dengue

Sex/ Blood Exposure and Fever

1. can have fvr without genital findings- hiv, syphilis (treponema pallidum) cmv, ebv, hep B
2. also from tattoo, piercing, share razor, blood xfsn

Eosinophilic Fever

1. >400 per cubic mm
2. due to blood CA or allergy or helminthic infc
3. hookworm, ascariasis, strongyloides, schistosomiasis, filariasis, visceral larva migrans, trichinosis, cocci
4. eval with stool for O&P
5. serology
6. blood smear
7. skin snips for microfilariae

Diarrhea

1. most respond to antibiotics or antimotility agents
2. as duration of diarrhea increases, higher chance of parasitic cause
3. giardia, cryptosporidiosis, entamoeba, cyclospora
4. dysentery if stool bloody, fvr or wbc in stool- invasive inflamm enteropathy
5. has abrupt onset, metastatic lesions, reactive arthopathies, or campylobacter assoc guillain barre- maybe flouroquinolone resis esp in SE Asia
6. amoebic dysentery insidious and can get amoebic liver abscess
7. if do not find infc cause of dysentery, eval pt for IBD or CA
8. prolonged diarrhea and malabsorption- giardia or tropical sprue- does not respond to removal of gluten from diet- tx with tetra and folate
9. also consider postinfectious disaccharidase deficiency or irritable bowel dz
10. if diarrhea starts >1 mo after travel- not caused by travel
11. tx regular travelers diarrhea with fluids, antimotility agents, abx- fluoro or macrolide
12. tx invasive enteropathy- bloody/ fvr- same but no antimotility agents
13. if bloody stool but no fvr, consider enterhemorrhagic E coli- do not give abx since will get hemolytic uremic syndrome in kids
14. examine stool if diarrhea invasive, persistent, unresponsive to standard tx or immune compromised
15. if persistent diarrhea, give empiric flouro or macrolide or consid metronidazole for giardia- most common parasite
16. try lactose free diet
17. chronic diarrhea usually self limited within 1 yr

Skin Conditions

Papules

1. insect bites- cluster or linear distribution
2. scabies- if sex active or backpacker
3. seabathers eruption- confined to skin covered by swim suit- jellyfish larvae trapped under cloth
4. cercarial dermatitis- skin exposed to freshwater schistosomes or coastal water clam diggers itch

Sub Q Swelling and Nodules

1. myasis- skin invaded by fly larvae- like boil but with central opening in which larvae may hide
2. tungiasis
3. loa loa
4. trypanosomiasis

Ulcers

1. pyoderma/ ecthyma- secondary staph cellulitits post bite
2. leishmaniasis
3. mycobacterium marinum

Linear and Migratory Lesions

1. cutaneous larvae migrans- by soil contact with dog/ cat feces
2. photodermatitis

Source

Mistry