[Multiple erythema annulare centrifugum associated with knee monoarthritis revealing Capnocytophagacanimorsus infection]. / Erythème annulaire centrifuge multiple et monoarthrite révélateurs d'une infection à Capnocytophaga canimorsus.

INTRODUCTION: Capnocytophagacanimorsus (C. canimorsus), a commensal Gram-negative bacillus found in the oral cavity of dogs and cats, is pathogenic for humans, with the most common clinical manifestations being septicemia, meningitis and endocarditis. Herein we report a case of CC bacteremia manifesting as multiple plaques of erythema annulare centrifugum associated with monoarthritis of the knee. PATIENTS AND METHODS: A 66-year-old man consulted for a skin rash and monoarthritis of the right knee with fever following an insect bite on his right hallux. Cutaneous examination revealed numerous erythematous annular plaques on the trunk and limbs with centrifugal extension. Analysis of synovial fluid from the right knee showed an inflammatory liquid with a sterile bacteriological culture and PCR was negative for Borrelia. C. canimorsus bacteria were isolated from blood cultures. 16S RNA PCR performed on the synovial fluid was positive for the same organism. The patient's history revealed that his hallux wound had been licked by his dog. DISCUSSION: C. canimorsus most frequently affects immunosuppressed subjects. Cutaneous signs are seen in half of all cases, most frequently presenting as cellulitis, pathological livedo or thrombotic purpura. We report herein a case of CC bacteremia in an immunocompetent patient manifesting as multiple plaques of erythema annulare centrifugum, an unusual sign, and monoarthritis of one knee.

[Atypical scleromyxedema with a granulomatous histological pattern and delayed sclerosis]. / Scléromyxœdème atypique, avec aspect histologique granulomateux et apparition retardée de la sclérose.

BACKGROUND: Papular mucinosis is characterised by primary mucin deposition in the dermis. The classification distinguishes between the localised form and the systemic form, which alone can result in complications, but this classification occasionally proves to be inadequate. Herein we report the progression of papular mucinosis, initially atypical due to the absence of cutaneous sclerosis and of misleading granulomatous histological features, which subsequently developed into characteristic scleromyxedema. PATIENTS AND METHODS: A 55-year-old male developed a rash comprising countless acral papules. Several biopsies were necessary before a diagnosis of papular mucinosis was made, due to the initial granulomatous appearance at histology. Tests showed monoclonal immunoglobulin of indeterminate significance, but, due to the absence of cutaneous sclerosis, we were able to conclude on typical localised papular mucinosis. Two years later, extensive sclerotic induration of the skin appeared and the diagnosis was modified to one of scleromyxedema. Treatment with intravenous immunoglobulins was given and proved efficacious, but relapse occurred on discontinuation of the therapy. DISCUSSION: Papular mucinosis is a rare disease of unknown physiopathology. The disease classification distinguishes between the localised and systemic forms, but it occasionally proves to be inadequate. Our case suggests a continuum between the localised and systemic forms of the disease. Further, the initial biopsies of acral papules in our patient had a misleading granulomatous appearance, as has been reported numerous times for the systemic forms. This granulomatous histological variant thus appears to constitute a diagnostic criterion for scleromyxedema.

[Severe edematous dermatomyositis]. / Dermatomyosite œdémateuse sévère.

INTRODUCTION: Edematous dermatomyositis is a rare entity with localized or generalized subcutaneous edema and only 21 cases have been reported in the literature. It is considered to be a severe form of dermatomyositis which needs quick therapeutic decision. We report 2 cases with difficult therapeutic decisions. OBSERVATIONS: Two patients aged 23 and 80 years were admitted in hospital for DM with typical cutaneous and muscular involvement without any sign of gravity and which have been treated by steroids: methylprednisolone bolus and prednisone. They both then developed severe edema of the upper limbs as well as worsening of the cutaneous and muscular symptoms with dysphagia. The addition of mycophenolate mofetil and intravenous immunoglobulin has permitted in the case of the first patient the disappearance of the cutaneous symptoms in particular the edema with restitution of the muscular force and withdrawal of the dysphagia and swallowing symptoms. The therapeutic failure for the second patient was due to a refusal of the treatment and a probable paraneoplastic context. CONCLUSION: Subcutaneous edema localized or generalized must not be confused with periorbital erythematous edema, classically observed in DM, nor with DM with mucinosis. Potential marker of gravity, it is often associated to important muscular weakness and dysphagia. In this case, an aggressive treatment associating corticosteroids, immunosuppressive therapy and intravenous immunoglobulin is necessary.