You-Chan Kim

Ecthyma gangrenosum without bacteraemia in a leukaemic patient

Ecthyma gangrenosum is a well recognized cutaneous manifestation of Pseudomonas aeruginosa infections in immunocompromised patients. Most cases of ecthyma gangrenosum have been associated with concomitant septicaemia. However, ecthyma gangrenosum rarely develops due to Ps. aeruginosa in the absence of bacteraemia. We report a rare case of a nonsepticaemic form of ecthyma gangrenosum presenting as a large solitary necrotic ulcer in a patient with acute myelogenous leukaemia. A culture from the lesion revealed the presence of Ps. aeruginosa, but the results of repeated blood cultures were negative. Histological examination revealed numerous tiny eosinophilic bacilli in the dermis and panniculus with Grams stain.

Benign glandular schwannoma

Glandular schwannoma is a rare variant of schwannoma characterized by the presence of glands in an otherwise typical schwannoma. We report a patient with benign glandular schwannoma occurring on the scalp, a site not previously reported. Histologically, a well‐defined, encapsulated oval nodule was observed in the subcutaneous tissue. The nodule was composed of a spindle cell component and glandular structures. The spindle cell component stained positively for S‐100 protein. All of the glandular epithelium stained with CAM 5.2 and epithelial membrane antigen but not with S‐100 protein. The glandular epithelium was focally positive for carcinoembryonic antigen. The histogenesis of the glandular elements in these tumours is still debated. The variable size of the glandular structures in our case was evidence against an entrapped normal sweat gland origin. The glandular epithelium did not stain with S‐100 protein at all, but stained with CAM 5.2, which did not support a direct metaplastic origin of the epithelial elements from the schwannian component. A few scattered CAM 5.2‐positive cells and microglandular structures in our case may be the initial differentiating epithelial elements possibly derived from pluripotential neural crest cells.

Granulomatous pyoderma gangrenosum: two unusual cases showing necrotizing granulomatous inflammation

We present two cases of pyoderma gangrenosum (PG) with unusual histopathological findings. The main histopathological feature of PG is usually massive neutrophilic infiltration; the neutrophil is thus the cytologic hallmark of PG. The occurrence of vasculitis is controversial. In our patients, in contrast, biopsy specimens revealed extensive granulomatous inflammation with massive tissue necrosis throughout the entire dermis and subcutaneous tissue and vascular involvement simulating many other granulomatous diseases. However, there was no evidence of systemic disease. Our cases may therefore represent a histopathologically distinct subset of PG.

Recalcitrant Oral Pyoderma Gangrenosum in a Child Responsive to Cyclosporine

We report a case of recalcitrant pyoderma gangrenosum which developed on the tongue of an 8‐year‐old, previously healthy boy without any systemic associated disease. The lesion was confined to the tongue and was not responsive to conventional treatment with prednisolone and sulfa drug, but it showed dramatic improvement with oral cyclosporine therapy. In addition, the histopathology of the lesion included many eosinophils, which caused difficulties in diagnosis to differentiate this condition from other oral ulcerative diseases showing tissue eosinophilia including eosinophilic ulcer of the tongue.