Unusual local complications of Vipera palaestinae bite.

BACKGROUND: Vipera palaestinae is the commonest venomous snake in Israel. V. palaestinae-specific antivenom is indicated for both systemic effects and marked progressive local signs. In our experience, clinicians are often not aware of the morbidity associated with the local effect of the venom and consequently do not administer the antivenom in envenomations with local effects only.
OBJECTIVE: To describe unusual local complications of inadequately treated V. palaestinae envenomation. CASE SERIES: Three cases of V. palaestinae bites involving distal parts of the limbs are reported. Within 36-48h tense swelling progressed to the trunk. Swelling involved the neck in two patients and was severe enough to cause dysphagia and to suggest impending upper airway obstruction. In the third patient, the swelling led to urine retention necessitating introduction of urinary catheter. V. palaestinae antivenom administration resulted in regression of swelling in two patients and in allergic reaction in the third.
CONCLUSION: Inadequately treated swelling caused by V. palaestinae envenomation may involve the trunk even when the site of the bite is remote. In some cases this may pose a threat to the function of vital structures such as the upper airways, call for unnecessary interventions and prolong hospitalization. It is recommended that V. palaestinae antivenom be administered whenever there is marked and progressive swelling even in the absence of systemic signs.