Visual Diagnosis at Spiders Bite

5th International Emergency Medicine Congress, Antalya, Türkiye, 27 - 30 Kasım 2025, ss.540-541, (Özet Bildiri)

Background and aim: Loxosceles species, commonly found in the Americas and the

Mediterranean region, are spiders whose bites can cause severe dermatonecrotic lesions.

Known as “brown recluse” spiders, their envenomation typically begins with mild pain,

erythema, and edema, but may progress to necrotizing wounds over several days or weeks.

Although cases reported in Turkey are limited, a few have been described in the western part

of the country.

Case: A 51-year-old woman presented to the emergency department with pain and redness in

the left thigh following a sudden sting while gardening. On initial evaluation, no significant

pathology was detected, and she was discharged with local wound care and oral cefuroxime;

however, she discontinued the antibiotic due to an allergic reaction. One week later, the patient

returned with a rapidly progressing lesion characterized by a necrotic plaque and surrounding

erythema. Examination revealed a 2×1 cm necrotic plaque with surface desquamation on the

proximal anteromedial thigh, surrounded by approximately 20×20 cm of erythema and a 1.5

cm wide irregular hyperpigmented band. A 4×4 cm subcutaneous induration was palpable

beneath the lesion. The patient exhibited no systemic findings. Laboratory values showed a

normal white blood cell count and a CRP level of 6.7 mg/L. ECG showed normal sinus rhythm

with a QTc of 387 ms. Treatment included intravenous paracetamol for analgesia, intravenous

antihistamine and corticosteroid for local reaction, and tetanus prophylaxis. With a preliminary

diagnosis of necrotizing spider bite (Loxosceles), she was admitted to dermatology, and the

necrotic wound was debrided by plastic surgery. Following conservative management and local

wound care, the lesion stabilized, and she was discharged after 3–4 days with normal

hematologic and coagulation parameters.

Conclusions: This case illustrates that Loxosceles bites may initially appear mild and

misleading but can progress into serious necrotizing lesions within days or weeks. Early

recognition and consideration of spider bite in rapidly evolving skin lesions are essential to

prevent complications. A multidisciplinary approach ensures timely diagnosis and appropriate

management. Greater clinical awareness, even in regions where such cases are rare, may

improve outcomes and reduce treatment delays.

Keywords: loxocelles, Spiders bite, Necrotizan bite