Reverse Passive Hemagglutination Tests for Rapid Diagnosis of Snake Envenomation

Abstract

Reverse passive hemagglutination (RPHA) tests for the detection of six major poisonous snake venoms of Thailand were studied. Three different species of red blood cells i.e., sheep (SRBC), human (HRBC) and chicken (CRBC) were sensitized with protein A-affinity purified rabbit antivenom IgG using chromic chloride as a coupling reagent. The properties of these sensitized erythrocytes with regard to sensitivity, specificity, stability to venom enzymes and storage etc., were studied and compared. The sensitivities of the RPHA tests in venom detection were 2 to 635 ng/ml. Cross-reactions were observed with heterologous venoms at concentrations at least 62 times higher than those observed with homologous venoms. After treatment with glutaraldehyde, the coupled red blood cells showed reduced sensitivity but were stable at 4 degrees C from 1 to 12 months depending upon the antibody and the species of erythrocytes. The entire test required 60 to 120 min. The RPHA using fresh SRBC correctly identified various venoms in 48 of 59 (81.3%) serum samples and 16 of 26 (61.5%) wound swabs. Venom mis-identifications were made in 2 sera (3.4%). In a comparison of 24 paired serum and wound swab samples, more positive identifications were made with serum than with swab samples but the difference was not statistically significant (p > 0.05).

Neurological Involvement and Hepatocellular Injury Caused by a Snake With Hematotoxin Envenomation

“…Severe liver injury was found in only 1 report of a patient who was bitten by Russell's viper. 15 Renal failure, which was a common complication (in 5 of 7 patients) in the case series of Russell's viper bites in Thailand, was not found in our patient. Therefore, a Russell's viper bite was less likely in our patient.…”

“…2 The epidemiology of snake bite was quite different in Bangkok, where green pit viper was much more prevalent (77% to more than 90%) than the other types of venomous snakes. 4,14 Although serologic testing to identify the species of snakes is the reliable method for diagnosing definite type of snake bite, 15,16 these tests are not available in most general hospitals, and the interpretation of blood tests of patients who received antivenom is still problematic.…”

Merit and Demerit of Polyvalent Snake Antivenoms

“…Since administration of a wrong mAV can lead to treatment failure and even death, a pAV, which can neutralize all the relevant venoms in the locality can be extremely useful in saving life. The need to accurately identify the culprit snake so that appropriate AV can be administered has let to the development of various rapid diagnostic kits for venom identification (Coulter et al, 1980;Kittigul and Ratanabanangkoon, 1993). However, only in Australia are snake identification test kits often used to aid physicians in AV treatment (White, 1998).…”

Cytotoxin antibody-based colourimetric sensor for field-level differential detection of elapid among big four snake venom

“…The identification of such protein complexes or their families is beneficial for its utilization in the continual development of strategies for detection of the snake species from the venom samples. Traditionally, diagnosis for snake envenomation relied primarily on visual examination followed by polyclonal sera-based detection strategies such as, immunodiffusion, immunofluorescence, hemagglutination, immunoelectrophoresis, radioimmunoassay; which in turn were limited by their tendency to crossreact with the closely related venoms, the reduced assay sensitivity, poor scalability for industrial production, and a prolonged-time of detection [21][22][23]. With advancing technologies, portable ELISA based kits, optical immunoassay, dot-blot assay, and family-specific protein identification tests were developed for detection of the specific venom using a three-step affinity-purified polyclonal antibody [24][25][26][27][28].…”