Pushing Glass (May 25, 2017)

The patient is a 74 year-old female who presents with a sudden rise in creatinine to 5.0. A week ago at her annual physical, her creatinine was 1.0. She presents to the hospital with dehydration and flu like symptoms. She has a history of hypertension and CLL which is followed by oncology.

What is the best diagnosis?

1. Acute interstitial nephritis

2. Chronic lymphocytic leukemia

3. Large B-Cell Lymphoma arising from chronic lymphocytic leukemia

4. Acute tubular injury

The best answer is (Answer 3) Large B-cell lymphoma arising from chronic lymphocytic leukemia.

The biopsy shows a very brisk interstitial infiltrate and but unremarkable glomeruli (A&B). On higher magnification, the cells are large with prominent nucleoli (C&D). Even though the patient does have a history of chronic lymphocytic leukemia, the size of the cells and the diffuse staining for CD20 (E) is in keeping with large B-cell lymphoma. Richter’s transformation refers to the development of aggressive lymphoma during the course of CLL. This is an uncommon complication which occurs in about 5% of patients with CLL. Diffuse large B-cell lymphoma occurs in the majority of these transformations. The presence of diffuse staining for CD20, a high proliferation index (MIB-1 stain not shown), and TP53 positivity (not shown) is consistent with a Richter’s transformation. Clinically, patients with Richter’s transformation usually present with rapidly enlarging lymph nodes, hepatosplenomegaly, and elevated serum lactate dehydrogenase levels. Acute interstitial nephritis could also cause a rapid increase in serum creatinine, but the cells in the infiltrate shown are neoplastic and not simply reactive. And, while acute tubular injury is present and likely a component of the increase in creatinine, but the predominant disease process is large B-cell lymphoma.