Hodgkin's lymphoma masquerading as vertebral osteomyelitis in a man with diabetes: a case report

Abstract

Introduction: Infection and malignancy often have common characteristics which render the differential diagnosis for a prolonged fever difficult. Imaging and tissue biopsy are crucial in making a correct diagnosis, though differentiating between chronic osteomyelitis and malignancy is not always straightforward as they possess many overlapping features.

Case presentation: A 52-year-old Caucasian man was treated with antibiotics for his diabetic foot infection after a superficial culture showed Staphylococcus aureus. He had persistent fevers for several weeks and later developed acute onset of back pain which was treated with several courses of antibiotics. Radiographic and pathological findings were atypical, and a diagnosis of Hodgkin's lymphoma was made 12 weeks later.

Conclusion: Clinicians should maintain a suspicion for Hodgkin's lymphoma or other occult malignancy when features of presumed osteomyelitis are atypical. Chronic vertebral osteomyelitis in particular often lacks features common to acute infectious disease processes, and the chronic lymphocytic infiltrates seen on histopathology have very similar features to Hodgkin's lymphoma, highlighting a similar inflammatory microenvironment sustained by both processes.

Figure 1

Representative tissue samples at 400× magnification. The initial L4 vertebral core biopsy (a) shows marrow replacement by a mixed inflammatory infiltrate consisting of small lymphocytes and some neutrophils in a fibrotic background. Rare large cells are present (arrow), but diagnostic Reed-Sternberg (RS) cells are not identified. Trilineage hematopoietic marrow was present in other areas (not shown). The right inguinal lymph node core biopsy (b) demonstrates a mixed inflammatory infiltrate consisting of small lymphocytes, histiocytes and eosinophils in a fibrotic stroma. Rare large degenerated cells are also present (arrow) but are non-specific findings. The left anterior cervical lymph node excisional biopsy (c) shows architectural effacement by a polymorphous infiltrate that includes scattered eosinophils, as well as diagnostic multinucleated RS cells (blue arrow) and mononuclear variants (black arrows) that stain positively for CD30 by immunohistochemistry (d).

Figure 2

MRI of spine demonstrating multifocal hypointensities (arrows) sparing the intervertebral disks in T1-weighted images (a). The same lesions (arrows) appear hyperintense on T2-weighted images (b). No inflammation of the paraspinal muscles or abscess was identified.

Figure 3

The scout film of the positron emission tomography-computed tomography (PET-CT) scan performed prior to this first round of chemotherapy (a) demonstrates diffuse regions of uptake involving multiple ribs, multiple vertebral bodies, the pelvis, the sternum and the scapula. There is also increased fluorodeoxyglucose (FDG) uptake in multiple bilateral lymph node regions extending from the jugular, supraclavicular, mediastinal, retroperitoneal, pelvic and inguinal regions, consistent with Hodgkin's lymphoma. There is increased FDG uptake in the posterior and right lateral walls of the nasopharynx. About two months after his first round of chemotherapy, a repeat PET-CT scan (b) showed a marked interval decrease in the FDG-avid metastatic burden.