High Levels of Serum Angiopoietin 2 and Angiopoietin 2/1 Ratio at the Critical Stage of Dengue Hemorrhagic Fever in Patients and Association with Clinical and Biochemical Parameters.

Longitudinal changes of serum angiopoietin 1 (Ang-1) and angiopoietin 2 (Ang-2) associated with endothelial stability in dengue patients with different disease stages were studied. Serum Ang-1 and Ang-2 levels were measured in confirmed dengue fever (DF) patients on admission (DFA, n = 40) and discharge (DFD, n = 20); in dengue hemorrhagic fever (DHF) patients on admission (DHFA, n = 40), at critical stage (DHFC, n = 36), and on discharge (DHFD, n = 20); and in healthy controls (HC, n = 25). DHFC had the highest serum Ang-2 and lowest Ang-1 levels compared to DFA, DHFA, and HC (P < 0.050). The ratio of serum Ang-2/Ang-1 in DHFC was the highest among all study categories tested (P < 0.001). Significant positive correlations were observed between serum Ang-1 and platelet count in DHFA (Pearson r = 0.653, P < 0.001) and between Ang-1 and pulse pressure in DHFC (r = 0.636, P = 0.001). Using a cutoff value of 1.01 for the Ang-2/Ang-1 ratio for DHFC, a sensitivity of 83.2% and a specificity of 81.2% discerning DF from DHF were obtained. Therefore, serum Ang-2/Ang-1 could be used as a biomarker for endothelial dysfunction in severe dengue at the critical stage.

Is Total Serum Nitrite and Nitrate (NOx) Level in Dengue Patients a Potential Prognostic Marker of Dengue Hemorrhagic Fever?

Potential use of total nitrite plus nitrate (NOx) and nitrite (NO2-) separately as surrogate markers for serum nitric oxide in severe dengue and their longitudinal changes along with the progression of infection was studied. Deproteinized sera from confirmed dengue fever (DF, n = 145) and dengue hemorrhagic fever (DHF, n = 74) patients on admission-A, critical-C, discharge-D, and convalescence-CON stages and from age-gender matched healthy individuals (HC, n = 77) were taken to assess NO2- and NOx levels using Griess and modified Griess assays. Serum NOx in DHFA was significantly lower compared to DFA (p < 0.001). HC had the lowest NOx and NO2- compared to all patient categories (p < 0.001) except NO2- in DF-CON and DHF-CON and NOx in DHF-CON. Serum NOx and NO2- in DHF patients admitted on fever day 3 (DHFA-3) was significantly lower compared to DFA-3 (p < 0.05). Cut-off values of 4.46 µM for NOx (91.3% sensitivity and 80.1% specificity) and 1.25 µM for NO2- (75.0% sensitivity and 73.3% specificity) were obtained for day 3 of fever. Serum NOx may be used as potential prognostic marker of DHF in patients presenting with DF in the early stage (on day 3 of fever) of the disease.

Rare cardiac sequelae of a hump-nosed viper bite.

BACKGROUND: The hump-nosed pit viper (Hypnale hypnale) is the commonest cause for venomous snakebites in Sri Lanka. Previously, it was thought to cause only local envenomation. However recently, several systemic effects and even mortality has been reported. Along with other snakes, such as the Indian cobra (Naja naja), the common krait (Bungarus caeruleus), the Russell's viper (Daboia russelii) and the saw-scaled viper (Echis carinatus), the hump-nosed viper is now also considered capable of causing lethal envenomation. Unlike other snake species, the systemic manifestations occurring through the bite of a hump-nosed viper, such as acute renal failure, thrombotic microangiopathy etc are rare and unpredictable. CASE PRESENTATION: A 49-year-old Sri Lankan Tamil male presented with a hump-nosed viper bite, which had resulted in a cardiac arrest within half an hour of envenomation. On arrival to the Emergency Treatment Unit, he was unconscious and without spontaneous breathing. Electrocardiography monitoring revealed ST elevation in leads II, III and aVF with reciprocal changes in leads I and aVL-indicating inferior wall infarction-as well as atrial fibrillation. Glasgow Coma Scale was 7/15, which indicated severe brain injury and electroencephalogram on day 10 revealed a low amplitude pattern compatible with diffuse brain damage. CONCLUSION: This case describes an authenticated case of myocardial infarction in a 49-year-old male following envenomation by a hump-nosed viper in Sri Lanka. This systemic effect of this viper's bite has not previously been described in the literature. This case report is intended to increase the vigilance for myocardial infarction following hump-nosed viper envenomation.