Protein-losing Enteropathy Complicated with Primary Intestinal Follicular Lymphoma

Abstract

Protein-losing enteropathy (PLE) is a rare syndrome characterized by hypoproteinemia due to gastrointestinal (GI) protein loss. Primary intestinal follicular lymphoma (PIFL), a specific variant of follicular lymphoma with essential only GI involvement, has not been reported as an etiology of PLE. We herein report a case of PLE complicated with PIFL that was successfully treated with rituximab, resulting in rapid improvement of PLE and a complete response of PIFL. Macroscopic findings of ulcerative lesions with diffuse involvement, which were precisely described by capsule and double-balloon enteroscopy at the diagnosis, also improved following the treatment. This case provides a clue suggesting factors that promote PLE in PIFL.

Keywords: primary intestinal follicular lymphoma; protein-losing enteropathy; rituximab.

Figure 1.

Map-like erosion (white arrows) surrounded by tiny whitish nodules (yellow arrows) in the mucosa was observed in the second portion of the duodenum (A). The duodenal mucosa was diffusely and circumferentially covered with tiny whitish nodules, and multiple round erosions were also observed (B). Histopathology of the duodenum showed proliferation of small lymphoid cells; immunohistochemical staining showing HE, CD20, CD10 and Bcl-2 staining (magnification, ×40) (C-F).

Figure 2.

Small mesenteric lymphadenopathy on enhanced computed tomography (A). The intense uptake of 18-fluorodeoxyglucose (FDG) in the second and third portion of the duodenum and jejunum at the initial diagnosis on FDG-PET in maximum intensity projection mode (MIP) (B).

Figure 3.

Capsule enteroscopy (A) and double-balloon enteroscopy (B) at the diagnosis. Erosions and ulcers (white arrows) were surrounded by tiny whitish nodules (yellow arrows). Histopathology of the ileum: immunohistochemical staining showing Hematoxylin and Eosin staining (magnification, ×40 and ×400) and D2-40 staining (×100). D2-40 is expressed in lymphatic endothelial cells (black arrows) and follicular dendritic cells (C). Technetium-99m-human serum albumin scintigraphy at the diagnosis (D). Labeled albumin was observed diffusely exudating at 4 hours after injection and moving to the colon at 24 hours after injection (black arrows).

Figure 4.

Clinical course with serum total protein and albumin levels.

Figure 5.

Esophagogastroduodenoscopy (A) and capsule enteroscopy (B) at the midpoint of rituximab treatment. Double-balloon enteroscopy after completing eight cycles of rituximab monotherapy (C). Technetium-99m-human serum albumin scintigraphy after completion of rituximab monotherapy (D).