Case of the Month - January 2011

Dr Philip Botha, Infectious Diseases Specialist, Tygerberg Hospital

facial flushing, headache, generalized myalgia and arthralgia, one day after arriving in South Africa on holiday. A blood smear for malaria parasites and a malaria antigen test were negative, but no additional investigations were requested. A presumptive diagnosis of Influenza was made and symptomatic treatment was prescribed. The patient developed a generalized rash and melaena stools 4 days later and was referred to the Emergency Unit of a Cape Town Hospital.

Apart from Thalassemia trait, there was no prior medical history. She lived in Bangkok, Thailand where she was employed as a teacher. She travelled to Shanghai for the purpose of work in the three months prior to visiting South Africa, but had returned to Bangkok for the week prior to travelling to South Africa. She received a Yellow Fever vaccination a number of years previously but did not receive other vaccinations recently and was on no regular medication. She had experienced multiple mosquito bites in Bangkok, but did not recall any other insect exposure, nor had she had any contact with animals. She had no risk factors for HIV infection and no contact with any person with fever or bleeding.

At the time of her presentation she was afebrile and haemodynamically stable. A diffuse erythematous macular rash with islands of sparing was noted (figure 1a&b). A tourniquet test was positive. There was no eschar, lymphadenopathy or hepatosplenomegaly. Evaluation of the cardiac, respiratory and neurological systems was non-contributory.

Fig 1a: Erythematous macular rash with island of sparing

Fig 1b: Close-up image of island of sparing on the background of a diffuse rash.

Special investigations:

White cell count 2.4 x 109/L; haemoglobin 12.4 g/dL; platelet count 20 x 109/L.
Liver function tests: ALT 63 IU/L; AST 174 IU/L.
INR & PTT normal.
CRP 6 mg/L.
Blood & urine cultures negative.
Chest radiograph within normal limits.
Blood sample sent to the NICD in Johannesburg for further testing.

A clinical diagnosis of severe dengue with haemorrhage was made.

Question 1: What is the differential diagnosis?

Continue to Answer 1