Deceptively complex diagnosis of early onset primary chronic osteomyelitis: a case report

Abstract Background Primary chronic osteomyelitis is a rare occurrence in the pediatric mandible though it exclusively affects the mandible with no age preference. The absence of pus, fistula and sequestration are characteristic with insidious onset lacking an acute state. It is a chronic inflammatory disease of unknown etiology. It has two peaks of incidence: initial peak at adolescence and the second peak after the age of 50 years. Clinical and radiological presentation does not suffice the diagnosis of Primary chronic osteomyelitis necessitating biopsy followed by histopathological examination. Use of several terms in the literature to describe this disease entity has led to further confusion. The Zurich classification system satisfactorily describes the early onset Primary Chronic Osteomyelitis based on etiology and pathogenesis. Case presentation A case of Early Onset Primary Chronic Osteomyelitis in a 10 year old boy is reported comprehensively from clinical presentation to diagnosis and treatment. A meticulous hierarchical order of investigations leads the way to final diagnosis with the aid of existing literature. Extra-oral biopsy, decortication and antibiotic therapy proved to be an effective treatment with no recurrence at 1 year follow-up. Conclusion The clinical and radiological features of Early Onset Primary Chronic Osteomyelitis are deceptively complex throwing an array of differential diagnosis including malignant tumors whilst histopathology reveals only chronic inflammation making this entity an enigma. This disease entity should be included in the differential diagnosis for a pediatric posterior mandibular swelling that occurs without an infectious nidus, pus discharge and fistula formation.