Rare Case of Gaucher's Disease Presenting as a Solitary Swelling of the Proximal Tibia Mimicking a Musculoskeletal Tumor in an Adult: A Case Report.

INTRODUCTION

Gaucher's disease is a congenital lysosomal storage disorder caused by an autosomal recessive mutation in B-glucocerebrosidase. It is a multi-system disease, wherein patients present with hematological abnormalities, joint pain, osteonecrosis, and developmental delay. We present a case of 38-year-old male with a painless solitary soft-tissue swelling over the left proximal tibia, eventually diagnosed it to be a case of Gaucher's disease. This case is unique in the literature, because this subcutaneous Gaucher mass was not associated with a significant past history and was being evaluated as a standard approach to a bone tumor.

CASE PRESENTATION

A 38-year-old man presented to our outpatient department with a solitary, painless soft-tissue swelling of the left proximal tibia noticed 6 months back, which has gradually progressed to a present size of 9x5 cm over a period of 6 months. General physical examination revealed moderate splenomegaly. Radiographs showed an osteolytic lesion in the left proximal tibia without cortical erosion. Radiographs for skeletal survey revealed similar osteolytic lesions elsewhere. Hematological investigations revealed thrombocytopenia. A serum protein electrophoresis was found to be normal and the urine was negative for myeloma proteins. Blood workup for endocrine abnormalities was within normal limits. MRI of the lesion suggests bone infarct. Biopsy from the lesion showed a giant binucleate storage cell filled with glucocerebrosides suggestive of Gaucher's disease. The diagnosis was confirmed by elevated plasma levels of glucocerebrosidases.

CONCLUSION

Gaucher's disease is a rare metabolic disease of the bone which may mimic a primary bone tumor or metastasis. A step-wise meticulous approach with biopsy and elevated plasma levels of glucocerebrosidase helps establish the diagnosis. Once must have a high index of suspicion for Gaucher's disease in an adult with multiple osteolytic lesions without any significant past medical and surgical history.