Typhoid and Parayphoid fever

Typhoid and Paratyphoid fever manifest as a diarrhoeal enteric fever that is caused by the gram negative bacilli Salmonella typhi and S. paratyphi (serovars A,B,C).  Paratyphoid fever causes similar symptoms but is generally more benign and from here we will refer to both as Enteric fever.

Enteric fever may be responsible for up to 3% of ill travellers with a febrile illness (Reference - N Engl J Med 2006 Jan 12;354(2):119).  Between 1985 and 1994, 2445 patients were reported to the CDC in the USA:

• Mortality 0.4%
• international travel within the previous 30 days was seen in 72% of cases
• 6 countries accounted for 80% of cases - Mexico, India, Philippines, Pakistan, El Salvador, Haiti
• Reference - Arch Intern Med 1998 Mar 23;158(6):633

The human is the only host for these GNBs, and they live in the colon in the active state but can be carried within the gallbladder.  They are transmitted via the faeco-oral route.

Patients usually present as a returned traveller from SE Asia with variable symptoms including diarrhoea or constipation, abdominal pain, rash, and prolonged fever.  Examination may reveal high temperature, tender splenomegaly, or "Rose spots" (evanescent abdominal papules).

Differential diagnosis includes:

• Non-infectious gastroenteritis
• Malaria
• Dengue
• Leptospirosis
• Measles
• Chikungunya

The diagnosis is made on the basis of Blood Cultures and serologic testing.  Unfortunately the Widal Test (serology) is negative within the first week.  The untreated prognosis is death (10 - 30%) or resolution within 4 weeks, complications manifesting as sepsis, gastrointestinal haemorrhage and perforation, encephalitis, and metastatic abscesses.

Prevention with parenteral vaccination (Typherix - GSK, in Australia) or oral vaccination (Vivotif - CSL, in Australia) may be indicated for travellers to an endemic area.  Treatment is with fluoroquinolones or 3rd-generation cephalosporin, however Ciprofloxacin resistance is becoming an increasing problem in the sub-continent and SE Asia.  Susceptibility tests should be performed.

Caring for the critically ill

Give your patient a fast hug every day!

This mnemonic can be used to reduce errors and apply protocol-driven, evidence-based medicine at the bedside.  It can be applied daily on ward rounds in the ICU, or used as part of the package of care delivered in the ED on arrival of the critically ill patient

F  -  feeding
A  -  analgesia
S  -  sedation
T  -  thromboembolism prophylaxis
H  -  head of bed elevation
U  -  ulcer prophylaxis
G  -  glucose control

Vincent JL, Crit Care Med 2005 Vol. 33, No. 6