Abstract
CONTEXT
Many bites from mildly venomous elapids occur but identification or presence of systemic envenoming is rarely confirmed.
OBJECTIVE
To confirm systemic envenoming and binding of venom components to a commercial antivenom in a definite bite by the Ornamental Snake (Denisonia maculata) using enzyme immunoassays.
CASE
A 9-year old boy was bitten by an identified Ornamental Snake. He developed nausea, vomiting, local pain, and swelling. He had a leucocytosis (white cell count, 20.8 × 10(9)/L), an elevated international normalised ratio (INR) of 1.6, but otherwise normal blood tests including D-Dimer and activated partial thromboplastin time. He was treated with Australian Black Snake antivenom because the commercial venom detection kit was positive for Black snake. He was admitted for 36 h with continuing local pain and swelling requiring parenteral analgesia.
MATERIALS AND METHODS
Blood samples were collected with informed consent for measurement of venom and antivenom concentrations. Venom-specific enzyme immunoassays were developed using the closely related D. devisi venom with Rabbit anti-Notechis (Tiger Snake) and anti-Tropidechis (Rough-scaled Snake) IgG antibodies to detect venom in serum. Standard curves for measured venom versus actual venom concentrations were made to interpolate Denisonia venom concentrations. In vitro procoagulant and anticoagulant activity of venom was assayed.
RESULTS
Denisonia venom was detected in the pre-antivenom sample as 9.6 ng/mL D. devisi venom. No antigenic venom components were detected in post-antivenom samples and there were high antivenom concentrations. D. devisi venom had mild in vitro procoagulant activity with a minimum concentration required to clot after 5 min of 2.5-5 μg/mL and even weaker anticoagulant activity.
CONCLUSIONS
Denisonia bites appear to cause local effects and possibly mild systemic envenoming (with only non-specific systemic symptoms and leucocytosis), confirmed by detection of antigenic venom components in blood. A significant coagulopathy does not appear to occur.
TY - JOUR
T1 - A definite bite by the Ornamental Snake (Denisonia maculata) causing mild envenoming.
AU - Isbister,Geoffrey K,
AU - Gault,Alan,
AU - Tasoulis,Theo,
AU - O'Leary,Margaret A,
Y1 - 2016/02/08/
PY - 2016/2/9/entrez
PY - 2016/2/9/pubmed
PY - 2016/7/12/medline
KW - Cross-neutralisation
KW - elapid
KW - snake envenoming
KW - snake-bite
KW - venom
SP - 241
EP - 4
JF - Clinical toxicology (Philadelphia, Pa.)
JO - Clin Toxicol (Phila)
VL - 54
IS - 3
N2 - CONTEXT: Many bites from mildly venomous elapids occur but identification or presence of systemic envenoming is rarely confirmed. OBJECTIVE: To confirm systemic envenoming and binding of venom components to a commercial antivenom in a definite bite by the Ornamental Snake (Denisonia maculata) using enzyme immunoassays. CASE: A 9-year old boy was bitten by an identified Ornamental Snake. He developed nausea, vomiting, local pain, and swelling. He had a leucocytosis (white cell count, 20.8 × 10(9)/L), an elevated international normalised ratio (INR) of 1.6, but otherwise normal blood tests including D-Dimer and activated partial thromboplastin time. He was treated with Australian Black Snake antivenom because the commercial venom detection kit was positive for Black snake. He was admitted for 36 h with continuing local pain and swelling requiring parenteral analgesia. MATERIALS AND METHODS: Blood samples were collected with informed consent for measurement of venom and antivenom concentrations. Venom-specific enzyme immunoassays were developed using the closely related D. devisi venom with Rabbit anti-Notechis (Tiger Snake) and anti-Tropidechis (Rough-scaled Snake) IgG antibodies to detect venom in serum. Standard curves for measured venom versus actual venom concentrations were made to interpolate Denisonia venom concentrations. In vitro procoagulant and anticoagulant activity of venom was assayed. RESULTS: Denisonia venom was detected in the pre-antivenom sample as 9.6 ng/mL D. devisi venom. No antigenic venom components were detected in post-antivenom samples and there were high antivenom concentrations. D. devisi venom had mild in vitro procoagulant activity with a minimum concentration required to clot after 5 min of 2.5-5 μg/mL and even weaker anticoagulant activity. CONCLUSIONS: Denisonia bites appear to cause local effects and possibly mild systemic envenoming (with only non-specific systemic symptoms and leucocytosis), confirmed by detection of antigenic venom components in blood. A significant coagulopathy does not appear to occur.
SN - 1556-9519
UR - https://www.unboundmedicine.com/medline/citation/26852775/A_definite_bite_by_the_Ornamental_Snake__Denisonia_maculata__causing_mild_envenoming_
L2 - https://www.tandfonline.com/doi/full/10.3109/15563650.2015.1128545
DB - PRIME
DP - Unbound Medicine
ER -