Half a Face, a Whole Story: The Enigma of Parry–Romberg Syndrome

Facial asymmetry is a condition where one side of the face differs from the other. It can arise from a variety of conditions, including genetics, medical and environmental influences affecting skin, muscles, and bone in varying proportion leading to noticeable differences in facial appearance. Among different causes, Parry–Romberg syndrome (PRS) is a very rare neurocutaneous syndrome that manifests between the ages of 2 and 20 years. A 5-year-old girl presented with progressive right-sided facial atrophy for 1.5 years. Examination revealed muscle wasting and hyperpigmentation without systemic involvement. Investigations showed normal hematology, negative antinuclear antibody, and lymphocytic perivascular infiltrates on skin biopsy. Magnetic resonance imaging demonstrated subtle left parietal lobe hyperintensity with atrophy of right-sided subcutaneous fat and muscles. Clinical, histopathological, and imaging findings established the diagnosis of PRS. Early recognition of PRS facilitates counseling, reduces psychosocial burden, and enables timely intervention.