Jesús D Guerra-Leal1, Luis A Medrano-Danés1, Alberto Montemayor-Martinez1, Edelmiro Pérez-Rodríguez2, César E Luna-Gurrola3, Roberto Arenas-Guzman4, Julio C Salas-Alanís5. 1. Department of Radiology and Imaging, Universidad Autonoma de Nuevo Leon, Facultad de Medicina y Hospital Universitario "Dr. Jose E. Gonzalez", Monterrey, Mexico. 2. Department of Surgery, Universidad Autonoma de Nuevo Leon, Facultad de Medicina y Hospital Universitario "Dr. Jose E. Gonzalez", Monterrey, Mexico. 3. Department of Microbiology, Universidad Autonoma de Nuevo Leon, Facultad de Medicina y Hospital Universitario "Dr. Jose E. Gonzalez", Monterrey, Mexico. 4. Department of Dermatology, Mycology Section, Hospital General Dr. Manuel Gea Gonzalez, Mexico City, Mexico. 5. Department of Research in Dermatology, Hospital ISSSTE Lic. Adolfo Lopez Mateos, Mexico City, Mexico.
Abstract
BACKGROUND: Mycetoma is a chronic, localized infection caused by fungi and bacteria. It usually affects the skin, subcutaneous tissue, and bone of exposed areas with deformity of the affected limb, ulcers, and fistula; however, pain is not severe, therefore the patient comes late to hospital for care. OBJECTIVE: To establish the diagnosis of mycetoma in the foot by imaging and identify the principal radiological signs. MATERIALS AND METHODS: Six patients with foot mycetoma were evaluated with plain x-ray, ultrasound, and magnetic resonance (MR) after confirming the diagnosis by histopathology and culture. RESULTS: All patients presented the MR "dot-in-circle" sign; four presented "punched out" bone lesions on plain x-ray. The six patients had fistulas, ulceration, a seropurulent exudate, edema, and a foot deformity. Four patients had N. brasiliensis infection with positive anti-Nocardia IgG antibodies, and only half presented bone lesions. CONCLUSION: Characteristic findings were foot deformity, edema, bone lesions, ulcers, fistulas and the presence of the "dot-in-circle" sign. We recommend a comprehensive study of patients with plain x-ray and MR.
BACKGROUND:Mycetoma is a chronic, localized infection caused by fungi and bacteria. It usually affects the skin, subcutaneous tissue, and bone of exposed areas with deformity of the affected limb, ulcers, and fistula; however, pain is not severe, therefore the patient comes late to hospital for care. OBJECTIVE: To establish the diagnosis of mycetoma in the foot by imaging and identify the principal radiological signs. MATERIALS AND METHODS: Six patients with foot mycetoma were evaluated with plain x-ray, ultrasound, and magnetic resonance (MR) after confirming the diagnosis by histopathology and culture. RESULTS: All patients presented the MR "dot-in-circle" sign; four presented "punched out" bone lesions on plain x-ray. The six patients had fistulas, ulceration, a seropurulent exudate, edema, and a foot deformity. Four patients had N. brasiliensis infection with positive anti-Nocardia IgG antibodies, and only half presented bone lesions. CONCLUSION: Characteristic findings were foot deformity, edema, bone lesions, ulcers, fistulas and the presence of the "dot-in-circle" sign. We recommend a comprehensive study of patients with plain x-ray and MR.
Authors: Ahlem Bellalah; Nouha Ben Abdeljelil; Manel Njima; Seifeddine Ben Hammouda; Sarah Ben Khalifa; Mustapha Koubaa; Abdelfatteh Zakhama; Rim Hadhri Journal: Clin Case Rep Date: 2021-03-16