A 16 y.o. presents with a rash and hypotension
What could be wrong?
this lesion was seen on her back
the rash spread over the upper back
Our patient had loxoscelism; a systemic reaction to a brown recluse spider bite. On presentation with a diffuse rash she had mottling of the skin and a wide pulse pressure. Initially, toxic shock was considered
She was briefly on pressors and given broad spectrum antibiotics. She developed mild non cardiogenic pulmonary edema and was covid negative. She developed hemolytic anemia six days after the rash and had a decline of 1.5 g/dL every twelve hours requiring 2 U of packed RBCs. The lesion on her back was felt to be the site of the bite.The rash began to exfoliate and was felt to be consistent with Acute Generalized Exanthematous Pustulosis secondary to the toxin produced by the spider. All symptoms resolved, her hgb was stable, and she was discharged 8 days after admission.
Desquamation in our patient
Loxoscelism was first described in 1879 in Tennessee. The spiders are found in the South, West, and Central Midwestern states. They prefer isolated spaces like basements, closets or attics. Their venom contains phospholipase and sphinomyelinase D which activates complement causing dermonecrosis and systemic manifestations. These enzymes are responsible for hemolysis, thrombocytopenia and renal failure.
6 eyes and a violin shape on the thorax mark the brown recluse.
Most commonly, the spider is not seen since the bites are painless and patients are often treated for cellulitis. There is no recommended treatment other than supportive care. At times a black eschar develops centrally which can be removed.
FUN FACT
Spiders have been blamed for many illnesses one of the most interesting is the dancing mania which occurred in Europe between the 14th and 17th centuries.(also called St. Vitus’s dance).
People who were bitten by a wolf spider (Lycosa tarantula, no relation to tarntula spiders) engaged in frantic dancing. The tarntella dance supposedly was a cure for tarantism.
Vetter R, Barger D. An infestation of 2.055 brown recluse spiders and no envenomations in a Kansas home: implications for bite diagnoses in nonendemic area.2002 Journal of Medical Entomology, vol 39, no 6:948-951
Tambourgi D, Paixao-Cavalcante D, et al. Loxosceles sphingomyelinase induces complement-dependent dermonecrosis, neutrophil infiltration and endogenous gelatinase expression . 2005. Journal of Investigative Dermatology, vol. 124(4) 725-731.
Nag A, Datta , Das , et al. Acute kidney injury and dermonecrosis after Loxosceles reclusa envenomation. 2014.Indian Journal of Nephrology, vol 24 (4246-248.