Spiders

Question 1

Black widow spider causes what syndrome and via what mechanism

Answer 1

Latrodectism: painful muscle rigidity +/- numbness radiating from bite site and autonomic disturbances such as abdominal cramping, HTN, N/V for 1-3 days via neurotoxin (alpha-latrotoxin)

Question 2

Official name of the black widow spider and appearance

Answer 2

Lactrodectus mactans with red hourglass on abdomen

Question 3

Tx of black widow bite

Answer 3

Ice to site to decrease venom spread
antivenom if available (watch for hypersensitivity reaction)
Opioids and muscle relaxants

Question 4

Brown recluse spider official name and appearance

Answer 4

Loxosceles reclusa with dark violin shaped marking on its back

Question 5

Clinical manifestations of brown recluse bite

Answer 5

Necrotic slowly healing lesions: develops as a rapidy blue-gray macular halo around puncture site (+/- cyanotic pustule/vesicle/bulla at bite)

• severe pain at site as skin infarcts
• rarely see severe systemic reactions with DIC, renal failure, etc

Question 6

Tx of brown recluse bite

Answer 6

1. RICE with aspirin and tetanus toxoid if needed

2. If severe skin necrosis: cephalosporins and analgesics needed, can consider dapsone as well