CHEST Guidelines-A-38-Year-Old-Woman-With-an-Osteolytic-Rib-Lesion

A-38-Year-Old-Woman-With-an-Osteolytic-Rib-Lesion_

Pdf Summary

A 38-year-old woman presented to the emergency department with lower back pain, where a CT scan revealed an osteolytic lesion on the right ninth rib. Further investigations, including repeat chest radiographs and CT scans, confirmed an expansile, lytic lesion with a pathologic fracture. The patient reported intermittent night sweats and a mild weight loss, but denied any recent trauma or malignancy. Blood tests showed normocytic anemia and elevated acute-phase reactants, but normal calcium and parathyroid hormone levels.<br /><br />Given these findings, an excisional biopsy of the affected rib was performed. Histology of the excised rib displayed a cellular lesion with intervening fibrous septae and mixed inflammatory cells, including lymphocytes and plasma cells. Immunohistochemical staining showed histiocytes positive for CD68 and S-100, but negative for CD1a, consistent with Rosai-Dorfman disease (RDD).<br /><br />RDD, also known as sinus histiocytosis with massive lymphadenopathy, is a rare, benign disorder characterized by accumulation of histiocytes. It usually presents in childhood or early adulthood, more commonly in males and those of African descent. RDD can cause significant morbidity when vital organs are involved. Although it mainly affects lymph nodes, extranodal manifestations are possible, with osseous involvement being rare.<br /><br />The condition is generally self-limiting and often resolves spontaneously, although localized forms may require surgical excision. In this case, the diagnosis of RDD, isolated to bone, required excision, given the pathologic fracture and expanding nature of the lesion. The patient recovered well post-surgery with no further complications reported.<br /><br />This case exemplifies the need for thorough investigation of atypical accidental findings and highlights the importance of considering rarity in diagnosing solitary bone lesions, especially RDD, which should remain a differential consideration in such cases.

Keywords

osteolytic lesion

Rosai-Dorfman disease

lower back pain

excisional biopsy

pathologic fracture

immunohistochemical staining

histiocytes

extranodal manifestation

sinus histiocytosis

self-limiting disorder