Biology Reference
In-Depth Information
Assessment of
H. gigas
based on available evidence: Hazard Level 3/4
[Most
bites feature uncomplicated local effects (typically, mild bleeding, limited edema,
pain, etc.)]. Larger specimens may produce more extensive local effects, including
ecchymoses and greater edema. Acquired hypersensitivity to Duvernoy's secretions
[e.g., in those with a history of repetitive exposure to snakes (wild and/or captive),
snake venoms/products, shed skins, etc.] may contribute to the clinical manifesta-
tions that occasionally are caused by bites from these snakes (see Section 4.6).
4.4.4
Philodryas olfersii latirostris
4.4.4.1 Background and Consideration of an Aberrant Case
The most commonly reported features of
P. olfersii
bites and the toxinology of
members of this genus were described in Section 4.2 and
Table 4.1
. Of the three
subspecies of
P. olfersii
(
P. o. olfersii
,
P. o. hebeus
, and
P. o. latirostris
), only
P. o. latirostris
figures in a documented report suggesting systemic effects (Peichoto
et al., 2007a;
Table 4.1
). This case described the uncomplicated and medically
insignificant bite of
P. o. latirostris
inflicted on a reportedly healthy 29-year-old
herpetologist. Although the victim had been bitten by an indeterminate number of
“colubrids” prior to this incident, no history of serious effects was reported. Also,
the victim had no history of venomous snakebites and had never been given anti-
venom. The minor local effects of this bite quickly subsided, and the victim was
asymptomatic for approximately 2 days following this incident, at which time
he experienced a brief (an estimated 5 min) episode of dizziness. Four days later
(6 days after the bite), the victim noted persistent dizziness, and presented at an
emergency room with “severe rotatory dizziness,” nausea, and vomiting (Peichoto
et al., 2007a). The patient required assisted ambulation as he was reportedly
“unsteady” on his feet. A CT scan of the head was unremarkable and otological and
neurological examinations were within normal limits. There was no observed spon-
taneous or gaze-evoked nystagmus. The patient was treated with antihistamines and
glucocorticoids. The nausea and vomiting subsided within 24 hours with a sustained
vertigo for several days thereafter. Full resolution occurred within 2 weeks (Peichoto
et al., 2007a). The authors remarked, “Although it is difficult to prove that the pre-
sentation of labyrinthine syndrome and the snakebite are actually associated, this
case would have to be taken into account to alert professionals of the health care
area about the necessity of attending carefully accidents involving colubrid snakes
…
” (Peichoto et al., 2007a). Thus, these workers “assumed” the vertigo and related
symptoms were an “effect of ophitoxemia” (Peichoto et al., 2007a).
4.4.4.2 Commentary and Critique
This case offers another opportunity for detailed analyses that can highlight and
emphasize the need for carefully prioritized, logical differential diagnoses when con-
sidering snakebite presentations that differ from the vast majority of formally docu-
mented cases. The assignment of this case to an “effect of ophitoxemia” is unsupported
