Anterior Mediastinal Myelolipoma: A Case Report and Review of the Literature.

BACKGROUND Myelolipoma is a benign tumor, commonly found in the supra-renal gland, which is composed of mature fatty tissue admixed with hematopoietic elements. However, there are several extra-adrenal sites reported in the literature and thoracic myelolipoma is an unusual location for extra-adrenal myelolipoma. CASE REPORT We present the case of a 71-year-old man previously diagnosed with hypertension who was admitted due to a motor vehicle injury with a lumbar spine fracture. The patient developed non-ST segment elevation myocardial infarction during admission. A coronary angiogram revealed three-vessel disease. Triple coronary artery bypass grafting (CABG) surgery was planned. Upon opening the chest through median sternotomy, a retrosternal adherent mass was incidentally discovered. The mass was excised and histopathological evaluation showed it was myelolipoma in the anterior part of the mediastinum. CONCLUSIONS It is well known that myelolipoma occurs in extra-adrenal sites, and is rarely found at unexpected site, as in our case, which was found incidentally at the anterior mediastinum. With an extensive literature review, we found only 1 case located in the anterior mediastinum. It is crucial to know that myelolipoma can occur in the anterior mediastinum to avoid pitfalls with other differential diagnoses, especially when it is found incidentally and requires a frozen section examination, as it is difficult to diagnose through radiologic imaging only because it can overlap with tumors that are rich in either adipose tissue or hematopoietic elements. However, it affects patient management, and patients usually need only follow-up instead of going through invasive procedures for resection of non-functional tumors, especially in older patients or patients with comorbid diseases.

Coincidental light chain induced proximal tubulopathy with lupus nephritis: a case report and review of the literature.

BACKGROUND: We report a case of light chain proximal tubulopathy associated with lupus nephritis in a patient known to have systemic lupus erythematosus. The kidney can be injured in several ways in any of these disorders. Light chain proximal tubulopathy is a rare form of renal tubular injury that may occur in and complicate plasma cell dyscrasia, characterized by cytoplasmic inclusions of the monoclonal light chain within proximal tubular cells. Lupus nephritis is a common form of renal injury as it occurs in about 25-50% of adult patients with systemic lupus erythematosus. CASE PRESENTATION: We present a 57-year-old African patient known to have systemic lupus erythematosus and hypertension presented with a new complaint of microscopic hematuria. A renal biopsy was performed and revealed lupus nephritis class II concurrently associated with light chain induced proximal tubulopathy. A subsequent bone marrow biopsy was performed, which revealed multiple myeloma. CONCLUSIONS: We report a case of coincidental lupus nephritis and proximal tubulopathy featuring a combined constellation of rare histopathological features that might add to the relationship between systemic lupus and paraproteinemia.