Keywords
intestinal lymphangiectasia - focal jejunal lymphangiectasia - obscure gastrointestinal
bleeding - CT imaging - capsule endoscopy
Introduction
Intestinal lymphangiectasia (IL) is a rare disorder characterized by dilated lymphatic
vessels in the intestinal wall. It can be primary, due to congenital lymphatic abnormalities,
or secondary, resulting from lymphatic obstruction. Depending on the site of blockage
of mesenteric lymphatic drainage, IL may be generalized or localized.[1] Focal IL is a rare entity with only a limited number of cases reported globally.
While IL often presents with malabsorption and protein-losing enteropathy, gastrointestinal
(GI) bleeding is an uncommon manifestation, particularly in focal IL. Here, we describe
a case of focal jejunal lymphangiectasia presenting as obscure GI bleeding.
Case Report
A 50-year-old man of Cameroonian origin presented to the hematology department with
a long-standing history of iron deficiency anemia and recurrent melena necessitating
multiple blood transfusions. He had undergone multiple evaluations in the past, including
upper and lower GI endoscopies, bone marrow studies, and computed tomography (CT),
all of which were noncontributory. He was admitted for further evaluation and management.
The patient had no comorbidities and was hemodynamically stable. Blood investigations
revealed hemoglobin of 8.2 g/dL, mean corpuscular volume of 66 fL, and iron profile
with serum iron of 19 µg/dL, and transferrin saturation of 5%. Peripheral smear showed
microcytic hypochromic anemia. Bone marrow studies showed hypercellular marrow, trilineage
hematopoiesis with erythroid hyperplasia consistent with iron-deficiency anemia. The
patient underwent a PET-CT scan, which showed mildly hypermetabolic splenomegaly and
diffuse skeletal hypermetabolic activity without definite corresponding CT scan abnormalities,
likely representing a hematopoietic response. No other abnormal focal lesions were
detected. The patient was conservatively managed with intravenous and oral iron supplementation
and was discharged with advice for a gastroenterology review.
Two months later, the patient re-presented with recurrent melena and was admitted
to the gastroenterology department for further evaluation. Colonoscopy and upper GI
endoscopy were repeated; however, they failed to provide any additional diagnostic
information. A contrast-enhanced CT angiography was performed, which came out as normal
except for mild hepatosplenomegaly. No evidence of active bleeding, bowel thickening,
or focal lesions was identified.
Subsequently, capsule endoscopy was performed, which revealed a localized segment
of white punctate and plaque-like areas in mid-jejunum ([Fig. 1]) extending approximately for a length of 6 to 8 cm with few areas of active ooze,
suggestive of focal lymphangiectasia. A retrospective review of the prior imaging
revealed an eccentric focal non-enhancing septate fluid density lesion in mid-jejunum
seen persistently in both PET-CT and CT angiography studies ([Figs. 2] and [3]). The lesion was previously overlooked as normal jejunal mucosal folds with fluid-filled
lumen. The rest of the bowel was normal with no other focal lesions. No associated
mesenteric changes or ascites were seen. Other secondary causes of lymphangiectasis
were also ruled out.
Fig. 1 (A and B) Capsule endoscopy images show punctate and plaque-like white areas in mid-jejunum,
giving a “snowflake-like appearance.” Few areas of active ooze are seen (white arrows
in B).
Fig. 2 Plain (A), arterial phase (B), and venous phase (C) CT images from PET-CT study done at initial admission show an eccentric fluid density
non-enhancing lesion (white arrows) in mid-jejunum with intact serosal surface.
Fig. 3 Arterial phase (A) and venous phase (B—axial, C—coronal, D—sagittal) images of the CECT done 2 months later at second admission show persistent eccentric
septate non-enhancing low attenuation lesion (white arrows) in mid-jejunum.
The patient underwent diagnostic laparoscopy followed by laparoscopic-assisted small
bowel resection. The gross specimen ([Fig. 4]) of the resected small bowel showed a short segment of grey-white granular mucosa
with prominent mucosal folds and focal polypoidal areas with intact serosa. Histopathological
analysis revealed multiple polypoid lesions with moderately to severely dilated mucosal
and submucosal lymphatics, filled with edematous fluid and occasional blood, confirming
small bowel lymphangiectasia ([Fig. 5]).
Fig. 4 (A and B) Gross specimen of the resected mid-jejunum showing a short segment of grey-white
granular mucosa with prominent mucosal folds and focal polypoidal areas with intact
serosa (B).
Fig. 5 Hematoxylin and eosin stain: (A) Whole mount view of jejunal tissue. (B) 10× magnification view showing dilated mucosal lymphatics with loss of crypts. (C) 5× magnification view showing moderately to severely dilated submucosal lymphatics.
(D) Dilated lymphatics lined by a single layer of flattened endothelial cells filled
with edema fluid and blood.
The postoperative course was uneventful. The patient remained hemodynamically stable,
tolerated soft oral diet, melena resolved, and was discharged with dietary recommendations
and follow-up advice.
Discussion
Intestinal lymphangiectasia is an uncommon disorder characterized by dilated mucosal
and submucosal lymphatic vessels within the intestinal wall, leading to lymph leakage
into the GI tract. Primary IL generally occurs in children and adolescents due to
a congenital abnormality of the lymphatic system. In contrast, secondary IL is more
commonly seen in adults and results from lymphatic obstruction and increased lymphatic
pressure arising from various conditions, including lymphoma, systemic lupus erythematosus,
inflammatory bowel disease, malignancies, constrictive pericarditis, and following
abdominal surgeries and radiotherapy.[2] According to the distribution, IL can be either generalized or focal. Most reported
cases of IL are of the generalized form. Focal or localized IL is extremely rare with
only a limited number of cases documented globally, and is considered secondary to
a localized developmental abnormality of lymphatic vessels.[3]
The clinical manifestations of IL are diverse, most often presenting with symptoms
related to protein-losing enteropathy, including edema, diarrhea, and malabsorption.
However, GI bleeding as seen in our case is a rare presentation, especially in focal
IL. The pathophysiology behind bleeding in IL is not entirely understood. One proposed
mechanism involves the obstruction of normal lymphatic drainage, leading to increased
pressure and the subsequent formation of abnormal connections between the lymphatic
and vascular systems. This can result in the rupture of these vessels into the intestinal
lumen, causing bleeding. Poirier and Alfidi reported a case of IL presenting with
severe GI bleeding in which lymphangiography demonstrated the passage of contrast
medium from abnormal intra-abdominal lymphatics into the GI tract. They postulated
that abnormal vascular–lymphatic communications could be the source of bleeding in
their case.[4]
Diagnostic approaches for IL include imaging studies such as contrast-enhanced computed
tomography (CECT) and magnetic resonance imaging (MRI), endoscopic imaging, and histopathological
confirmation. CECT in generalized forms of IL may reveal characteristic findings such
as diffuse nodular thickening of the small bowel or linear hypodense streaks representing
dilated lymphatic channels. Associated findings can include mesenteric fat stranding,
ascites, pleural effusion, and other edematous changes.[1] Non-enhanced, fluid-sensitive MR sequences may show bright signal intensity corresponding
to lymphangiectasia in the mucosa.[5] However, being a rare entity, limited documentation exists on the imaging characteristics
of focal IL. Reported cases describe focal areas of concentric bowel wall thickening
with low attenuation on CT, reflecting the presence of lipid-rich chylous fluid within
the dilated lymphatics.[1] A “halo sign” has also been described, consisting of a thickened, low-attenuation
inner ring representing dilated lymphatics and a higher-attenuation outer ring of
muscularis propria and serosa.[5]
[6] In contrast to the previously reported concentric low-attenuation bowel wall thickening
in focal IL, our case demonstrated an eccentric, low-attenuation lesion. In the absence
of high clinical suspicion and knowledge, these imaging findings may be misinterpreted
as focal fluid-distended bowel loops due to water meal administered prior to CT/MR
enterography or may mimic other pathologies such as bowel ischemia, inflammatory bowel
disease, lymphoma, or neoplastic mucinous deposits.
The term “obscure GI bleeding” is used for recurrent or persistent GI bleeding from
a source that cannot be identified using upper or lower GI endoscopy, as seen in our
case.[7] In such situations, capsule endoscopy has emerged as a valuable tool, as it allows
for direct visualization of the small bowel mucosa.[7]
[8] Endoscopy demonstrates scattered white spots overlying the small intestinal mucosa,
a finding commonly referred to as “snowflake appearance.”[5]
Therapeutic strategies for IL depend on the extent and severity of the disease. Conservative
management includes dietary modifications, such as a low-fat, high-protein diet supplemented
with medium-chain triglycerides, aiming to reduce lymphatic pressure and protein loss.[9] In cases where IL is localized and symptomatic, surgical resection of the affected
bowel segment can be curative.[3]
Conclusion
Localized IL is a rare cause of GI bleeding. A keen eye and strong clinical suspicion
are crucial for identifying focal IL on contrast-enhanced CT, as the findings are
often subtle and easily missed. A multidisciplinary approach is crucial for diagnosis
and management in challenging cases of obscure GI bleeding. This case underscores
the importance of considering focal IL in the differential diagnosis of obscure GI
bleeding.
