Metachronous Venous Malformation Masquerading as an Obscure Gastrointestinal Bleed.

Vascular malformation of the gastrointestinal (GI) tract along with metachronous lesions elsewhere in the body is extremely rare. We report an unusual case of a female child, with a history of venous malformation excision over the right leg presenting with severe iron-deficiency anemia. Although venous malformations of the small bowel are a rare cause of occult GI bleed, in the presence of cutaneous vascular lesions, there should be a high index of suspicion of a vascular malformation, along with the other causes of GI bleed in children. Copyright:

INTRODUCTION

In children, painless bleeding per rectum is not only a clinical but also a diagnostic challenge for pediatricians and pediatric surgeons. The common causes are polyps (solitary or multiple), Meckel's diverticulum, and vascular malformations.[1] Gastrointestinal (GI) venous malformations are rare, accounting for 7%–10% of all the benign vascular tumors commonly occurring in the small bowel, colon, and rectum.[2] Presence of a cutaneous vascular malformation should alert a differential diagnosis of a GI vascular lesion, which is not readily diagnosed by routine investigations.

We detail the presentation and management of a female child with unexplained iron-deficiency anemia, painless GI occult bleed, and a metachronous vascular malformation elsewhere in the body which has rarely been reported in literature.

CASE REPORT

A 4-year-old female child was brought with unexplained weakness and generalized tiredness, with a history of a vascular lesion over the right leg which was excised a year ago. A hematological workup revealed severe anemia with a hemoglobin of 4 g/dl. Prior to this, she was seen in the pediatric outpatient department, suspected to have severe iron-deficiency anemia, secondary to poor intake, and was treated with oral supplemental iron. With no improvement seen, she was admitted for evaluation and transfused with packed red blood component, following which she symptomatically improved with a hemoglobin of 6.5 g/dL. The parents were instructed to follow-up at the hematology clinic and continue oral iron supplements. Two months later, she was brought to the emergency, with a hemoglobin of 4 g/dL, for which she was transfused with packed red blood components and thereby requiring multiple transfusions to attain a hemoglobin of 10 g/dl. Further diagnostic workup was suggestive of severe iron-deficiency anemia, i.e., microcytic hypochromic anemia, mean corpuscular volume was persistently low below 60 fL, serum ferritin levels were 20 ng, and total iron-binding capacity was more than 13 μmol/L. The stool was positive for occult blood, and at this point, an internal source of bleeding was suspected, for which she was referred to a pediatric gastroenterologist for an upper and lower GI endoscopy which was inconclusive. Other imaging modalities such as ultrasonography and contrast-enhanced computed tomography (CT) scan of the abdomen and pelvis were normal. However, a 99M Technetium Pertechnetate scan revealed a “hotspot” increased radioactivity in the right lower abdomen, as shown in Figure 1a, based on which a diagnosis of Meckel's diverticulum was considered.

Figure 1

(a) Meckel's scan, suggestive of a small bowel active bleed (hot spot). (b) Diagnostic laparoscopy revealed two vascular lesions in the jejunal wall

The child underwent a diagnostic laparoscopy, during which we could identify two bluish-colored patches on the jejunal wall, as depicted in Figure 1b. On proceeding with an exploratory laparotomy, there was no evidence of a Meckel's diverticulum, but two adjacent foci of vascular malformation were seen in the terminal jejunum. Segmental bowel resection and anastomosis were done. Cut sections of the specimen revealed two bluish-stalked masses which were suggestive of a vascular malformation, as depicted in Figure 2a. The child had an uneventful postoperative period, tolerating a normal diet with normal bowel movements. The histopathological examination revealed features suggestive of a venous malformation of the small intestine (jejunum), as depicted in Figure 2b, which were similar to the features described in the vascular lesion excised from her right leg a year ago. At follow-up after 2 months, she was healthy, and her hemoglobin was 11 g/dl with no problems in her routine activities.

Figure 2

(a) Gross specimen of the resected jejunal segment with two vascular lesions. (b) Histopathology showing (1) vascular tumor in jejunal mucosa with focal ulceration (2) lined by flattened endothelium, few blood vessels filled with red blood cell and thrombi. (3) Comprising numerous dilated blood vessels

DISCUSSION

Vascular malformations of the small intestine account for about 5% of all the benign GI tumors followed by that of the rectum and colon. They have been reported to masquerade as immunodeficiency disorders in children.[3] Vascular anomalies are classified into vascular tumors and vascular malformations by Mulliken and Glowacki. This classification was adopted by the International Society for the Study of Vascular Anomalies which was revised in 2014. Vascular tumors are further classified as benign and malignant. Vascular malformations are classified into Simple (capillary, lymphatic, venous, arteriovenous malformations and arteriovenous fistula), Complex vascular malformations and those associated with other anomalies or syndromes.[4] Multiple cutaneous lesions may be a marker for extracutaneous hemangiomas commonly involving the liver. Extracutaneous lesions involving the GI tract could present with abdominal discomfort, nausea, vomiting, generalized weakness, fatigue, and melena.[5]

Previously, a preoperative diagnosis of these lesions was difficult, and almost all cases were diagnosed during or after the surgery.[6] The diagnostic tools include imaging tests such as abdominal ultrasonography, contrast-enhanced CT scan, magnetic resonance imaging, Meckel's scan, and an angiography of the abdomen. A capsule endoscopy is found to be the best diagnostic tool for such small bowel lesions; however, in younger children, it is difficult to swallow and is contraindicated in intestinal obstruction.[7]

For medical care, corticosteroids, antiangiogenic agents, interferon-alpha, and sclerotherapy have been also described in literature with their own limitations. However, in our case, as a Meckel's scan showed evidence of an activity in the GI tract, we considered a surgical intervention for further management instead of a medical management. Multifocal lesions are present in blue rubber bleb nevus syndrome, which is characterized by multifocal discrete venous malformations that most frequently occur on the skin and within the GI tract. These patients usually have chronic melena or hematochezia causing chronic anemia requiring multiple blood transfusions and they rarely present with massive GI hemorrhage.[4] Our case had a similar presentation and hence can be labeled as blue rubber bleb nevus syndrome. Since these lesions are known to be multiple, it is necessary to resect all of them to get total clearance of the symptoms. Use of sirolimus therapy to control bleeding from these lesions has been mentioned in the literature, but limited data are available regarding the experience with this drug in clinical practice.[4] Vascular malformations in the small bowel should be treated with segmental resection, whereas colon lesions should be treated with ileocecectomy, right hemicolectomy, left hemicolectomy, or segmental resection, depending on the location and extent of the haemangioma.[8] In our case, in view of the isolated jejunal lesions involving a short segment, we chose to do a segmental bowel resection anastomosis.

Iron-deficiency anemia in children needs to be investigated appropriately and often extensively to identify the cause, as dietary iron-deficiency anemia is rare beyond infancy.[9]

In conclusion, a metachronous vascular lesion on the right foot initially should have prompted the clinician of the possibility of a vascular malformation causing the occult GI bleed over other causes in this child and possibly avoided multiple blood transfusions. Better knowledge and understanding of these presentations should help to reduce the delay in diagnosis and avoid inappropriate management.

Declaration of patient consent

The authors certify that they have obtained the appropriate consents from the patient's guardians; for reporting their child's images and other clinical information in the journal. The patient's guardian understands that child's names and initials will not be published, and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.