To the Editor:
Reported ocular exposures to crotalid (rattlesnake) venom are rare. A search of the scientific literature revealed no animal studies and only a single human case report Citation[1]. We describe an ocular exposure to rattlesnake venom in an adult who was effectively managed at home.
The wife of a 45‐year‐old male contacted the local poison control center after her husband had just been squirted in the eye with rattlesnake venom at home. He had just beheaded a captured snake and was opening the snake's mouth with a key to show his children the fangs when a stream of venom was discharged, striking the patient in the eye. The patient immediately complained of mild ocular irritation. The poison specialist recommended immediate irrigation of the eye with room temperature tap water for at least 15 min. The patient was then instructed to go to his local emergency department for examination if the irritation persisted or worsened. Upon telephone follow‐up 1 hour later, the patient stated that his symptoms had resolved completely after copious irrigation and did not think that a medical evaluation was warranted. Further attempts to obtain follow‐up were unsuccessful.
Ocular exposure to tropical snakes, most notably Naja nigricollis, the black‐necked or spitting cobra, has produced significant eye injury Citation[3]Citation[4]Citation[5]Citation[6]. There is little literature, however, describing ocular exposure to crotalid venom, probably because this is an uncommon occurrence. Unlike the spitting cobra, crotalids lack a specifically developed “spitting” apparatus. We found only one peer‐reviewed case report of ophthalmic exposure to rattlesnake venom that describes only mild, transient irritation, similar to what was experienced by our patient. Based on these experiences, ocular exposure to crotalid venom may cause only mild symptoms if irrigated rapidly. However, with a paucity of literature on the subject no concrete conclusions can be drawn. Rapid decontamination with prolonged irrigation should be recommended for ocular exposure to crotalid venom, followed by physician or ophthalmologist evaluation if symptoms persist.
It is not uncommon for an envenomated patient to arrive at a health care facility with at least a portion of the dead snake in their possession. Often, the specific part brought in is the decapitated head of the snake. While identification of the particular species of the offending crotalid rarely changes treatment parameters, many patients fail to realize that decapitated heads are still a risk for envenomation Citation[7]Citation[8]Citation[9] or even ocular exposure. This case provides another example of why careless handling of severed rattlesnake heads should be discouraged.
References
- Troutman W. G., Wilson L. E. Topical ophthalmic exposure to rattlesnake venom. Am J Emerg Med 1989; 7(3)307–308
- Litovitz T. L., Klein‐Schwartz W., Rodgers G. C., Jr, Cobaugh D. J., Youniss J., Omslaer J. C., May M. E., Woolf A. D., Benson B. E. 2001 Annual report of the American association of poison control centers toxic exposure surveillance system. Am J Emerg Med 2002; 20(5)391–452
- Payne T., Warrell D. A. Effects of venom in eye from spitting cobra. Arch Opthalmol 1976; 94: 1803
- Warrell D. A., Ormerod L. D. Snake venom opthalmia and blindness caused by the spitting cobra (naja nigricollis) in Nigeria. Am J Trop Med Hyg 1976; 25: 525–529
- Ismail M., Ellison A. C. Ocular effects of the venom from the spitting cobra (naja nigricollis). J Toxicol Clin Toxicol 1986; 24: 183–202
- Hansen E. A., Stein E. A., Mader T. H., et al. Spitting cobra opthalmia in United Nations Forces in Somalia. Am J Opthalmol 1994; 117: 671
- Griffen D., Donovan J. W. Significant envenomation from a preserved rattlesnake head (in a patient with a history of immediate hypersensitivity to antivenin). Ann Emerg Med 1986; 15(8)955–958
- Keyler D. E., Schwitzer K. Envenomation from the fang of a freeze‐dried prairie rattlesnake head. Vet Hum Toxicol 1987; 29(6)440–441
- Suchard J. R., LoVecchio F. Envenomations by rattlesnakes thought to be dead. N Engl J Med 1999; 340(24)1930