Dermatomyositis: A Retrospective Study of Sixteen Cases

Introduction: Dermatomyositis is an inflammatory multisystemic disease characterized by muscle weakness with a characteristic and pathognomonic cutaneous eruption. Our purpose was to describe the common cutaneous, extra-cutaneous features and course of dermatomyositis in our institution. Method: In this retrospective study we reviewed the medical data of dermatomyositis registered cases in dermatology department at Treichville teaching hospital in Côte d'ivoire from 2004 to 2013. Diagnosis was assessed for each case using the Bohan and Peter criteria for dermatomyositis. Result: Sixteen cases which fulfilled at least three out of four of the Bohan and Peter criteria for dermatomyositis were analysed. Prevalence was 15.3 for 10000 consulting patients. The delay to establish the diagnosis after the onset of the disease was 4 months. The average age of patients was 39 years. The sex ratio was 1.2. Features were: hyperpigmentation of sun exposed sites in 100% of cases, symmetric erythema in 93.7% of the cases, facial oedema in 56.2% of the cases, poïkilodermatous lesions in 25% of the cases. Telangiectasia was noted in 6.2% of the cases. The average delay for occurrence of muscular symptoms after the onset of cutaneous symptoms was 1 month. The longest delay was 4 months. All cases had at least proximal muscles weakness. Three cases representing 18.7% of cases displayed oesophageal .muscles involvement. Muscular biopsy analysis performed in 10 cases that represent 62.5% of cases was specific in 4 cases (40%) and not in 6 cases (60%). Electromyogram was performed in 75% of cases and displayed myogenic deficit in all of them. Serum LDH level has been abnormal in all cases. Whereas serum CPK level has been abnormal in 87.5% of the cases. Two cases representing 12.5% of the cases had interstitial pneumonia and pericarditis. In an average period follow-up of 12 months death occurred in 6.2% of the cases and invalidity was constant. We used oral prednisone in 93.7% of cases. The maximal dose useful to induce remission was 60 mg of prednisone a day. The minimal dose useful for remission control was 10 mg a day. The average delay for partial remission was 10 days. Relapse occurred in all cases when decreasing doses of prednisone. Conclusion: We confirm that dermatomyositis is an uncommon disease. Our cases of dermatomyositis are relatively younger than those classically described. There was no sex predominance.