ABSTRACT
Limulus amoebocyte lysate test (LALT) was used to detect endotoxin-like substances in the plasma of 57 patients with dengue haemorrhagic fever and dengue shock syndrome (DHF/DSS), four patients with dengue fever and 20 control patients with other diseases. The LALT positivity rates in DHF/DSS and dengue fever patients were 43.9 and 25 per cent respectively, whereas all control patients were negative (p less than 0.0025). LALT positivity was highest on 5th and 6th days of admission with positive rates of 46 and 50 per cent respectively whereas the positive rates in those admitted on fourth and seventh days of admission were 29 and 33 per cent respectively. A follow-up in LALT positive patients showed a decline in the positive rates after admission. LALT positivity was observed in 48.8 per cent of DHF/DSS patients with shock and in 26.6 per cent of patients without shock.