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HKCEM College Tutorial
Fever of
traveler return
from tropical
area (2)
Author
Dr Poon Kin Ming
Oct 2013
What is tropical region?
Patient with fever after return from tropical region
What are your differential diagnoses ?
Diagnosis
▪Infectious diseases esp. tropical
illness
▪Autoimmune diseases
▪Malignancy
Infectious diseases that should not be missed
Protozoal
Malaria瘧疾
Virus
Dengue fever登革熱
Chikungunya fever基孔肯雅熱
Yellow fever黃熱病
Rickettsial diseases 立克次氏體病
Typhoid & Paratyphoid傷寒及副傷寒
Leptospirosis鈎端螺旋體病
Brucellosis布魯氏桿菌病
Relapsing fever回歸熱
Bacterial
How are you going to approach to a
patient with fever after travelling
back from tropical region?
Approach to patients with fever after return from tropical area
▪If patient’s condition not stable, proceed to
resuscitation
▪If stable, proceed to history, physical
examination, investigation & treatment
What would you ask in the history ?
History
▪ Approach to fever : TOCC
What does it stand for ?
- Continent visited
- Chemoprophylaxis or vaccination
- Mosquito bite / insect bite
- Onset of fever : Incubation period
- Fever pattern
Continent visited
Destination
Sub Saharan Africa
Common
Malaria,
Rickettsial dis.
Malaria,Dengue,
Enteric fever
Occasional
South & central Asia
Malaria,Dengue,
Enteric fever
Chikungunya
Latin American &
Caribbean
Malaria,Dengue,
Enteric fever
Leptospirosis,
Histoplasmosis
South East Asia
Dengue, Enteric fever,
brucellosis
Leptospirosis,
Chikungunya
Incubation periods
Short (<10days)
Acute gastroenteritis, Respiratory tract
infection, Dengue, Chikungunya,
Relapsing fever, Rickettsial infection
Medium (10-21days) Malaria, Enteric fever, Brucellosis,
Leptospirosis,
Q fever, viral hemorrhagic fever
Long (> 3 weeks)
Malaria, Brucellosis, Schistosomiasis,
Tuberculosis, amoebic liver abscess
Fever pattern
Pattern
Continuous
Description
Diseases
Constant fever with
variation
<1 °C
Typhoid fever, Rickettsial
infection, encephalitis
Intermittent
Temperature returns to normal
at least once during the day
Malaria, Dengue fever,
Leptospirosis, many
viral illness, abscess
Remittent
Fever does not return to
normal each day
Relapsing
Recurrent over days &
weeks
Typhoid fever, Tuberculosis,
endocarditis
Relapsing fever, brucellosis,
malaria, lymphoma
Physical exam
▪ General appearance & vital signs
▪ Jaundice & skin rash
▪ Lung & heart signs e.g. crepitation & murmur
▪ Neurological sign e.g. meningism
▪ Lymphadenopathy, hepatomegaly or splenomegaly
▪ Joint or calf tenderness
Physical signs
Maculopapular
rash
Dengue, rickettsial infection, leptospirosis
(Rose spot in typhoid fever,
Splinter hemorrhage in infective endocarditis,
Eschar in scrub typhus)
Lymphadenopathy
Dengue fever, rickettsial infection, rubella infection
Splenomegaly
Malaria, dengue fever, typhoid fever, rickettsial
infection, relapsing fever, brucellosis
Hepatomegaly
Viral hepatitis, malaria, typhoid fever, leptospirosis
Haemorrhage
Dengue fever, dengue hemorrhagic fever,
meningococcal septicaemia
Investigation
▪ CBC with D/C
- PMN leucocytosis: bacterial e.g. leptospirosis, relapsing fever, abscess
- Neutropenia : Arbovirus infection (include dengue), malaria, typhoid, brucellosis,
AIDS
- Lymphocytosis: viral infection
- Atypical lymphocyte: infectious mononucleosis
- Thrombocytopenia : malaria, viral infection (including rickettsial infection)
- thin & thick blood smear for malaria
▪ L/RFT
▪ Urine multistix & CXR
Investigation
▪ Specific tests:
▪ Immunodiagnosis including serology test and antigen detection
like ELISA, RIA & immunofluorescene test.
▪ Helpful in diagnosing hepatitis, dengue fever, rickettsial infection,
yellow fever, brucellosis.
Situation 1
▪ Fever + Maculopapular skin rash over the body
▪ What would you think of ?
Situation 1
▪ Fever + Maculopapular skin rash over the body
▪ What would you think of ?
▪ Dengue, Rickettsial infection, Leptospirosis and HIV
seroconversion
IF YOU SEE ROSE SPOT IN PATIENT’S BODY,
WHAT DO YOU THINK OF ?
▪If you see Rose spot in patient’s body,
what do you think of ?
▪Typhoid fever !
Have you heard of ?
▪ Very Sick People Must Take No Exercise
- Temporal relationship between the onset of fever and skin rash
( from D1 to D7)
Have you heard of ?
▪ Very Sick People Must Take No Exercise
- V – Varicella (chickenpox) (Day 1)
- S – Scarlet fever
- P – Smallpox
- M – Measles
(Day 4)
- T – Typhus
- N – Non specific
- E – Enteric fever
(Day 7)
Situation 2
▪ Fever + lymphadenopathy ?
Situation 2
▪ Fever + lymphadenopathy ?
▪ Dengue fever, Rickettsial infection, Rubella infection, & HIV
seroconversion
- Not a feature of malaria & typhoid fever !
Situation 3
▪Fever + splenomegaly + hepatomegaly ?
Situation 3
▪ Fever + splenomegaly + hepatomegaly ?
▪ Malaria, typhoid fever
If fever + splenomegaly,
think of dengue fever, Riskettsial infection, relapsing fever & Brucellosis
If Fever + hepatomegaly,
think of viral hepatitis & leptospirosis
Situation 4
▪Fever + haemorrhage ?
Situation 4
▪Fever + hemorrhage ?
▪Dengue fever, Dengue Hemorrhagic
fever, yellow fever, other viral
hemorrhagic fever, meningococcal
septicemia
Physical signs (summary)
Maculopapular
rash
Dengue, rickettsial infection, leptospirosis
(Rose spot in typhoid fever,
Splinter hemorrhage in infective endocarditis,
Eschar in scrub typhus)
Lymphadenopathy
Dengue fever, rickettsial infection, rubella infection
Splenomegaly
Malaria, dengue fever, typhoid fever, rickettsial
infection, relapsing fever, brucellosis
Hepatomegaly
Viral hepatitis, malaria, typhoid fever, leptospirosis
Haemorrhage
Dengue fever, dengue hemorrhagic fever,
meningococcal septicaemia
Some important tropical diseases
Malaria 瘧疾
▪ Protozoal parasite
▪ 4 species :
- Plasmodium falciparum (most lethal)
- P. vivax
- P. ovale
- P. malariae
- Vector : Mosquitoes Anopheles, which bite mainly between sunset
and sunrise
Anopheles 瘧蚊
Blood smear from a patient with malaria; microscopic examination shows
Plasmodium falciparum parasites (arrows) infecting some of the patient's red blood cells.
Management
- Rapid fluid replacement for dehydrated patients
- Parenteral infusion of quinine or artesunate.
- (Chloroquine is longer recommended due to its widespread resistance)
Prevention : Protection from vectors
- Insect repellents, mosquito coils, protective clothes
Chemoprophylaxis :
- Weekly chloroquine/mefloquine at least 1 week before departure and continued
for 4 weeks after the last possible exposure to infection
Dengue fever 登革熱
▪ Caused by Dengue virus, transmitted by the mosquito Aedes aegypti
▪ Dengue hemorrhagic fever (DHF) :
Dengue fever + Hemorrhagic tendency + Plasma leakage
- Dengue shock syndrome : (DSS)
DHF + shock + rapid pulse with narrow pulse pressure < 20mmHg
Aedes Aegypti 埃及伊蚊
Treatment
▪ Supportive
▪ Correct hypovolaemia in patietns with DHF
& DSS, which lasts or 24 - 48 hrs
▪ Monitor BP, haematocrit, platelet count,
R/LFT, signs of bleeding
▪ Blood product transfusion maybe required
Chikungunya fever 屈公病
▪ Caused by Chikungunya virus, transmitted by Aedes mosquitoes
▪ African language : that blends up
▪ An acute febrile mosquito borne illness characterized by prolonged
arthralgia (over wrist, ankle & knee) and rash
▪ Symptomatic tx
▪ No vaccine available
Ankle bends and skin rash
Yellow fever 黃熱病
A mosquito (Aedes) -borne viral illness characterized by acute onset
of brief & recurrence of fever, hepatitis, jaundice, albuminuria, renal
failure, shock & generalized hemorrhage
Typhoid & paratyphoid
傷寒及副傷寒
▪ Bacterial infection: Salmonella Typhi or Paratyphi
▪ An illness characterized by fever, headache, bradycardia,
splenomegaly, rose spots on the trunk +/ - GI symptoms
▪ Treatment: rehydration + antibiotics of fluoroquinolone such as
ciprofloxacin
Red spots in typhoid fever
Rickettsial Disease立克次氏體病
▪ An arthropod-borne viral infection characterized by fever,
chills, muscle pain and body rash.
▪ Scrub typhus 叢林/鼠蝨斑疹傷寒: a large punch out skin
ulcer at the site of bite of an infected mite.
▪ Spotted fever 斑疹熱 : an eschar 焦痂 at the site of the
arthropod bite, with nearby painful & swollen lymph node
▪ Q fever : endemic in area with sheep, cattle and goat
industry 人畜共染
Eschar
Leptospirosis 鈎端螺旋體病
▪ An acute febrile bacterial infection with Leptospira after
exposure to environmental water contaminated by urine
of domestic or wild animals.
▪ Characterized with headache, myalgia, meningeal
irritation, abdominal pain, nausea, oliguria, skin rash
▪ Effective antibiotics include cefotaxime, doxycycline,
penicillin, ampicillin, and amoxicillin
Leptospirosis
electron micrograph
Relapsing fever 回歸熱
▪ An arthropod – borne bacterial infection (Borrelia) with alternating
febrile period & petechial rashes.
▪ Fever lasting for 2-9 days alternate with afebrile periods of 2-4
days
▪ Tetracycline-class antibiotics are most effective
Brucellosis 布魯氏桿菌病
▪ is a highly contagious disease caused by ingestion of unsterilized milk
or meat from infected animals or close contact with their secretions
▪ Antibiotics like tetracyclines, rifampicin, and the aminoglycosides are
effective
In summary
▪ Detail history and physical examination
▪ Exclusion of life threatening infection or diseases with public
health risk (e.g. measles, rubella) is the priority
▪ Don’t miss those life threatening infections include Falciparum
malaria, dengue haemorrhagic fever/ dengue shock syndrome,
leptospirosis, infective endocarditis and meningoccocaemia.
Thank You