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significant medical effects in humans. The lack of verified identification of the culprit
snake must be considered, but as the bites were insignificant, there is still no link that
can be confidently established between the bites and the fatal progressive neuropathy.
4.4.5.2 Conclusion and Assessment of
P. najadum
Chroni et al. (2005) documented an unfortunate case of fatal progressive neuropathy
and proposed possible linkage with bites from a presumed
P. najadum
as the precipitat-
ing cause (i.e., immune response “against neural antigens generated by snake toxins”;
Chroni et al., 2005). Although several rare instances of GBS have been documented
postenvenoming from elapids or crotaline viperids, even these cases may have alterna-
tive etiologies and this case involved medically insignificant bites from a colubrid spe-
cies that has no documented medical importance or known appreciable toxicity. Due
to the fatal outcome and the apparent insignificance of the purported
P. najadum
bites
delivered to the patient, there is no evidence sufficient to assign this fatal case to the
bites from this colubrid. This case highlights the need for thorough documentation of
these cases including verification of identity of the involved snake and scrutiny of any
other factors (e.g., recent/concomitant immunizations, infections, family history) poten-
tially contributing to the etiology of such progressive and life-threatening neuropathies.
Assessment of
P. najadum
based on available evidence: Hazard Level 3
(see
Table 4.3
).
4.4.6
Hierophis (Coluber) viridiflavus
: A Case of Neurotoxic Colubrine
Bite or a More Common Etiology?
4.4.6.1 Analysis and Critique
This single case of a purportedly medically significant bite from a
H. viridiflavus
(family Colubridae, subfamily Colubrinae; Plate 4.16A-D) occurred near Bordeaux,
France. Published as an abstract, this brief report summarizes the events that ensued
after the 20-year-old male victim was allegedly bitten by a 100-cm
H. viridiflavus
(Bedry et al., 1998;
Table 4.1
) after placing the wild-caught snake around his neck. It
is important to note that the victim did not express awareness of being bitten. Rather,
his companions informed him that he had received a bite from the snake. The patient
had ingested “a few pints” of an alcoholic beverage (presumably beer) prior to this
incident. Approximately 30 min later, the victim reported dizziness and was “affected
by a major muscular weakness” (Bedry et al., 1998). After 3 h, the victim, anxious
and drowsy, was admitted to the ICU. Shortly thereafter, he experienced vertigo and
vomiting. Neurological examination revealed “an inability to open his eyes and lift-
ing his head off the bed” (Bedry et al., 1998). Laboratory results were unremarkable
(although specific details of the tests included were not mentioned) aside from a blood
alcohol level of 2.1 g/L (Bedry et al., 1998). The reported neurological signs “declined”
within 90 min and the vomiting ceased within 24 h. The authors considered two pos-
sible causes for the observed syndrome: ethanol intoxication or an “envenomation with
an incomplete curare-like syndrome (ptosis, muscle weakness of the head)” (Bedry et
