Imaging findings of ecthyma gangrenosum, an unusual complication of pseudomonas sepsis

Abstract

A child with acute lymphoblastic leukemia and pseudomonas sepsis rapidly developed left foot pain and swelling. A diagnosis of ecthyma gangrenosum was made. The clinical and imaging features of this unusual entity are discussed. To our knowledge, this is the first description of the MR imaging findings of ecthyma gangrenosum.

Keywords: MRI; ecthyma gangrenosum; pediatric; pseudomonas.

Fig. 1

This intra-operative photo demonstrates a central necrotic ulcer with an erythematous halo at the plantar aspect of the left foot

Fig. 2

a This T1-W image (TR, 416.5; TE, 14.6) of both feet demonstrates cutaneous and subcutaneous edema with enlargement of the muscles at the plantar aspect of the left foot. Hypointense bone marrow signal is present in both feet secondary to the underlying diagnosis of ALL. b Inversion recovery image (TR, 3500; TE, 56.3) demonstrates subcutaneous edema, enlargement of the left plantar muscles, and fluid between muscle and deep fascial planes. Bone marrow signal is increased in both feet secondary to ALL. c This post-contrast fat-suppressed T1-W image (TR, 416.7; TE, 14.5) shows a geographic pattern of absent enhancement (arrows) involving the plantar muscles compatible with necrosis and/or ischemia. Surrounding muscles enhance. Deep fascial enhancement is notably absent. When compared with pre-contrast fat-suppressed T1-W images (not shown), the marrow of the bones of the left foot appear to enhance when compared with the right. The patient did not have osteomyelitis