ORIGINAL ARTICLES
Clinical features of acute febrile thrombocytopaenia among patients attending primary care clinics
Another important aspect to look at is the association of duration of fever and the presence of thrombocytopaenia. Although there was no difference in the mean duration of fever among patients with thrombocytopaenia and normal platelet count, there were 5 times the odds of thrombocytopaenia if patients presented at day 3 of fever compared to those presented on day 1 or 2 of fever. This is not unexpected, as dengue patients usually develop thrombocytopaenia at day five to seven of illness when the fever starts to subside.5,14 The mechanism for such occurrence is due to increases peripheral platelet destruction and marrow suppression.14 Hence, it is advisable that all patients presenting on day 3 of fever should be offered a FBC test. On the other hand, doing a full blood count in a patients presenting early (i.e. day 1 or 2 of illness) may not be appropriate as the rate of picking up a thrombocytopaenia is low.
In this study, the data was collected prospectively in order to standardise the data collection and to minimise incomplete data. All selected patients selected had acute non-specific febrile illness from the outpatient setting. This was an important feature of this study as the studies in the past mainly recruited patients from hospital or suspected cases of dengue from outpatient setting, who might not represent the typical patients with acute non-specific febrile illness. Furthermore, previous studies had not looked into the association of clinical features and thrombocytopaenia among patients presented with acute non-specific febrile illness. Presence of thrombocytopaenia helps clinicians in assessing the severity of the illness;4-6 therefore it is critical for health care professionals to be able to detect thrombocytopenia among patients with acute non-specific febrile illness. Misdiagnosing a case of dengue infection without thrombocytopaenia may not be as disastrous as misdiagnosing a case of dengue infection with thrombocytopaenia, because dengue infection with normal platelet count represents a milder form of DF and do not require admission.
Conclusion
patients with nausea and vomiting should be referred for FBC in view of the higher possibility of thrombocytopaenia. This is important because clinical diagnosis of dengue infection is unreliable. Adopting this approach in managing patients with non-specific acute febrile illness can guide health care professionals to be more selective in requesting a full blood count.
ACKNOWLEDGEMENTS
We are grateful to Dr. Leelavathi, Dr. Hazizi, Dr. Aida, Dr. Wasilah, Dr. Nor Azila, M/A Azhar and Fairul for their help with data collection. I would like to thank all the laboratory assistants from Batu 9 Health Clinic and Primary Care Clinic Hospital Universiti Kebangsaan Malaysia Bandar Tasik Selatan, for performing the laboratory tests.
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