Histiocytosis X in an adult mimicking pyoderma gangrenosum

Atypical presentation of pioderma gangrenosum complicating ulcerative colitis: Rapid disappearance with methylprednisolone

Piodermal gangrenosum (PG) is an uncommon ulcerative cutaneous dermatosis associated with a variety of systemic diseases, including inflammatory bowel disease (IBD), arthritis, leukaemia, hepatitis, and primary biliary cirrhosis. Other cutaneous ulceration resembling PG had been described in literature. There has been neither laboratory finding nor histological feature diagnostic of PG, and diagnosis of PG is mainly made based on the exclusion criteria. We present here a patient, with ulcerative colitis (UC) who was referred to the emergency section with a large and rapidly evolving cutaneous ulceration. Laboratory and microbiological investigation associated with histological findings of the ulcer specimen allowed us to exclude autoimmune and systemic diseases as well as immuno-proliferative disorders. An atypical presentation of PG with UC was diagnosed. Pulse boluses of i.v. methyl-prednisolone were started, and after tapering steroids, complete resolution of the skin lesion was achieved in 3 wk. The unusual rapid healing of the skin ulceration with steroid mono-therapy and the atypical cutaneous presentation in this patient as well as the risk of misdiagnosis of PG in the clinical practice were discussed.

Histiocitosis de células de Langerhans

Histiocytoses originate from the proliferation of mononuclear phagocytes in different tissues. These entities make up a heterogeneous group, and are mainly classified as Langerhans cell histiocytoses and non-Langerhans cell histiocytoses. Langerhans cell histiocytoses have as a common characteristic the proliferation of dendritic antigen-presenting cells with phenotypical and ultrastructural characteristics of Langerhans cells. Infiltration may be limited to one organ, or may be disseminated. The prognosis and the treatment especially depend on the age of the patient and the number and dysfunction of the organs involved. Its etiopathogenesis is unknown, although most researchers currently believe that an alteration in the regulation of the immunological system occurs in these patients.

Pyoderma gangrenosum: clinicopathologic correlation and proposed diagnostic criteria

Pyoderma gangrenosum is a rare but significant cause of ulcerations. It is a diagnosis of exclusion. Herein, we suggest diagnostic criteria and some historical perspectives on the diagnosis of pyoderma gangrenosum.

Case reports and a review of the literature on ulcers mimicking pyoderma gangrenosum

Pyoderma gangrenosum (PG) is a rare, ulcerative skin disease. Diseases with cutaneous manifestations resembling PG may lead to the misdiagnosis of PG. We discuss two patients presenting with cutaneous ulcers originally thought to be PG, and review the literature on the clinical and pathologic characteristics of PG ulcers compared to PG-like ulcers in order to determine possible distinguishing features.

Skin ulcers misdiagnosed as pyoderma gangrenosum

BACKGROUND

Pyoderma gangrenosum is a diagnosis of exclusion, and the misdiagnosis of pyoderma gangrenosum can result in substantial complications in patients who have other causes of severe cutaneous ulceration.

METHODS

We reviewed the charts of 240 patients with a diagnosis of pyoderma gangrenosum who were evaluated at our institution from 1975 through 2000, including 157 consecutive patients treated for presumed pyoderma gangrenosum from 1984 through 1992. We also reviewed the English-language literature.

RESULTS

Ninety-five patients (49 from our institution and 46 described in the literature) had skin ulcers with a clinical resemblance to pyoderma gangrenosum. The final diagnoses were vascular occlusive or venous disease, vasculitis, cancer, primary infection, drug-induced or exogenous tissue injury, and other inflammatory disorders. Of the 95 patients studied, 64 had been treated for pyoderma gangrenosum for a median of 10 months (range, 3 to 180). These 64 included 15 of the 157 consecutive patients treated for pyoderma gangrenosum at our institution (10 percent). Of the ulcers in the 64 patients treated for pyoderma gangrenosum, it was clear that those in 23 patients (36 percent) did not respond to treatment directed at pyoderma gangrenosum, those in 8 (12 percent) were exacerbated by such treatment, and those in 15 (23 percent) improved with such treatment.

CONCLUSIONS

The misdiagnosis of pyoderma gangrenosum is not uncommon and exposes patients to risks associated with its treatment. A thorough evaluation is required in all patients suspected of having pyoderma gangrenosum in order to rule out alternative diagnoses.