Virchowian Leprosy Mimetizing Juvenile Systemic Scleroderma

Abstract

BACKGROUNDLeprosy, a chronic infectious disease caused by Mycobacterium leprae, affects the skin, peripheral nerves, upper respiratory tract, musculoskeletal system and eyes. As it presents a wide spectrum of clinical manifestations, it can be a diagnostic challenge, especially in early stages of disease. Some of these manifestations resemble pictures of rheumatic diseases that affect adults and children. Among the musculoskeletal manifestations of childhood leprosy are inflammatory chronic arthritis, mimicking juvenile idiopathic arthritis or spondyloarthritis, inflammatory swelling of the hands and feet, neuropathic arthritis, septic arthritis, arthralgias/ myalgias, soft tissue rheumatism and multisystem involvement similar to collagenases, including vasculitis and myositis. CASE REPORTWe report the case of a previously healthy 8-year-old boy admitted to the pediatric rheumatology unity due to the presence of puffy hands and fingers and hard and shiny edema of the lower limbs, suggesting systemic scleroderma diagnosis. He had an 11-month history of recurrent episodes of intermittent fever, plaque-like, erythematous, nonpruritic facial skin lesions and joint pain in the knees and ankles. On physical examination, he presented, in addition to the aforementioned findings, purpuric lesions on the toes, hepatosplenomegaly, arthralgias (wrist, small joints of the hands, knees and ankles) and erythematous plaques infiltrated in the bilateral malar region, nasal region and auricular pavilion. Complementary tests showed normocytic and normochromic anemia, leukocytosis, neutrophilia, thrombocytosis, elevation of inflammatory tests and negativity of ANA, RF, ANCA, anti-RNP and anti-Scl70. Due to the infiltrated skin lesions, lymph smear testing was performed, which was strongly positive, and a diagnosis of Virchowian leprosy associated with mixed leprosy reaction was made. There was clinical and laboratory improvement after initiation of multidrug therapy and systemic corticosteroid therapy. CONCLUSIONLeprosy is known as a great mimic of rheumatic diseases, often fulfilling diagnostic criteria for many of them. The multibacillary forms present greater musculoskeletal involvement. It should be considered in differential diagnosis of children with musculoskeletal symptoms, autoantibody positivity and cutaneous and/or neurological involvement.