Unusual Tuberculosis Mimicking Connective Tissue Disease: A Pediatric Case Report

Abstract

We reported a child with unusual extrapulmonary tuberculosis (TB) who was misdiagnosed with a connective tissue disease leading to treatment delay. A 13-year-old boy presented with subacute joint pain, headache and diplopia. The examination revealed swelling in the right knee, cervical lymphadenopathy, impaired abduction of right eye and multiple groups of follicular papules at right forearm, cheeks and buttocks. Blood tests showed mild anemia, thrombocytosis and high erythrocyte sedimentation rate. Serological tests including antinuclear antibody, rheumatoid factor, antidouble stranded deoxyribonucleic acid and anti-human immunodeficiency virus were negative. Brain magnetic resonance imaging (MRI) illustrated multiple lobulated dural thickening areas and a small infarction of left cerebellum. Chest film and tuberculin test were normal. Joint fluid analysis suggested reactive arthritis. Cultures for TB and fungus from cervical lymph node and forearm skin lesion were negative. After an extensive investigation, the presumptive diagnosis was non-specific connective tissue disorder. The arthritis and ophthalmoparesis initially responded to prednisolone, but arthritis relapsed at the third week of treatment, and intravenous cyclophosphamide was added. Three months later, left facial palsy had developed and ophthalmoparesis increased. New skin lesions also appeared over his axillae and groins. Axilla skin biopsy showed granulomatous abscesses with caseous necrosis leading to TB diagnosis. After treatment with anti-TB agents, clinical signs and brain MRI were completely resolved at 6- month-follow-up. Our report addressed that TB may mimic connective tissue diseases and temporarily respond to immunosuppressants. Because idiopathic pachymeningitis is rare in children, TB must be excluded in cases with meningeal thickening. Re-evaluation of TB is highly recommended in atypical systemic illnesses.