Appropriateness of the study of iron deficiency anemia prior to referral for small bowel evaluation at a tertiary center

Table 1 Clinical characteristics of patients referred to gastroenterology department for iron deficiency anemia study n (%)

Characteristics	Total (n = 77)
Age, yr (mean ± SD)	67.1 ± 16.7
Female	45 (58.4)
Provenience
General Practice	41 (53.2)
Hospital Specialties	32 (41.6)
Hematology	13 (16.9)
Internal Medicine	6 (7.8)
Cardiology	5 (6.5)
Nephrology	5 (6.5)
Pneumology	1 (1.3)
General Surgery	1 (1.3)
Cardiothoracic Surgery	1 (1.3)
Emergency Department	4 (5.2)
Hemoglobin, g/dL (mean ± SD)	8.8 ± 2.0
Microcytosis	55 (71.4)
Hypochromia	56 (72.7)

IDA: Iron deficiency anemia.

Table 2 Pre-referral study

Procedures	n (%)
Appropriate pre-referral study	17 (22.1)
EGD	75 (97.4)
H. pylori investigation	35 (58.3)
Colonoscopy	71 (92.2)
With quality standards	49 (63.6)
Without quality standards	22 (28.6)
Insufficient intestinal preparation	15 (19.2)
Incomplete	5 (6.5)
Non-recent	2 (2.6%)
Celiac Disease screening	19 (24.7)
Serologic testing	10 (13.0)
Duodenal histopathological investigation	7 (9.1)
Both	2 (2.6)
Additional pre-referral study
Iron metabolism tests	69 (89.6)
C-reactive protein	33 (42.9)
Vitamin B12	27 (35.1)
Folic Acid	27 (35.1)
Reticulocyte count	23 (29.9)
Peripheral blood smear	0 (0.0)
Ileoscopy	14 (20.0)
Gynecology evaluation1	3 (50.0)
Capsule endoscopy	3 (3.9)
Labelled red cell scintigraphy	5 (6.5)

¹Including only female patients younger than 40 years. EGD: Esophagogastroduodenoscopy; H. pylori: Helicobacter pylori.

Table 3 Univariate analysis of factors associated with the appropriateness of pre-referral evaluation n (%)

Characteristics	Appropriate	Incomplete	P value1
	(n = 17, 22.1%)	(n = 60, 77.9%)
Age, years (mean ± SD)	48.7 ± 17.7	72.3 ± 12.3	< 0.001
Female,	13 (76.5)	32 (53.3)	0.087
General Practice referral	7 (41.2)	34 (56.7)	0.258
Hemoglobin, g/dL (mean ± SD)	9.0 ± 2.4	8.7 ± 1.8	0.645
Microcytosis	13 (76.5)	42 (70.0)	0.750
Hypochromia	13 (76.5)	43 (71.7)	0.640
Female, < 40 yr	6 (100)	0 (0.0)	< 0.001

¹Student’s t-test, Mann-Whitney U test, Fisher’s exact test or the χ² test, as appropriate; P value of 0.05 indicating statistical significance.

Table 4 Evaluation after referral n (%)

Procedures	n (%)
In patients with further small bowel evaluation	56 (72.7)
EGD	4 (5.2)
Ileocolonoscopy	9 (11.7)
Capsule endoscopy	53 (68.8)
Device-assisted enteroscopy	7 (9.1)
CT-enterography	7 (9.1)
MRI-enterography	4 (5.2)
Meckel’s scan	4 (5.2)
In patients without further small bowel evaluation	21 (27.3)
EGD	7 (9.1)
Ileocolonoscopy	9 (11.7)

EGD: Esophagogastroduodenoscopy; CT: Computed tomography; MRI: Magnetic resonance imaging.

Table 5 Univariate analysis of factors associated with the decision to proceed to small bowel evaluation n (%)

Characteristics	SBevaluated	SB not evaluated	P value1
	(n = 56, 72.7%)	(n = 21, 27.3%)
Age, yr (mean ± SD)	65.0 ± 17.3	72.6 ± 14.2	0.077
Female	35 (62.5)	10 (47.6)	0.238
General Practice referral	27 (48.2)	14 (66.7)	0.148
Hemoglobin, g/dL (mean ± SD)	8.7 ± 2.1	9.2 ± 1.6	0.299
Microcytosis	40 (71.4)	15 (71.4)	0.933
Hypochromia	39 (69.6)	17 (81.0)	0.510
Female, < 40 yr	6 (100)	0 (0.0)	0.118
Appropriate study at referral	15 (26.8)	2 (9.5)	0.104
EGD	56 (100)	19 (90.5)	0.072
Quality colonoscopy	44 (78.6)	5 (23.8)	< 0.001
Celiac Disease screening	17 (30.4)	2 (9.5)	0.059

¹Student’s t-test, Mann-Whitney U test, Fisher’s exact test or the χ² test, as appropriate; P value of 0.05 indicating statistical significance. SB: Small bowel; SD: Standard deviation; EGD: Esophagogastroduodenoscopy.

Table 6 Diagnoses regarded as the likely causes of iron deficiency anemia

Diagnoses	n (%)
Upper GI tract	7 (9.1)
Gastric angioectasia(s)1	3 (3.9)
Gastric polyp(s)1	2 (2.6)
GAVE	1 (1.3)
Erosive gastritis1	1 (1.3)
Small bowel	26 (33.8)
Angioectasia(s)	14 (18.2)
Crohn’s disease	4 (5.2)
NSAIDs enteropathy	2 (2.6)
Neoplasia	2 (2.6)
Unspecified enteritis	2 (2.6)
Dieulafoy’s lesion	1 (1.3)
Inflammatory polyp	1 (1.3)
Lower GI tract	7 (9.1)
Angioectasia(s)1	4 (5.2)
Coloretal cancer	2 (2.6)
Polyp	1 (1.3)

¹Non-small bowel findings detected on SB studies. IDA: Iron deficiency anemia; GI: Gastrointestinal; GAVE: Gastric antrum vascular ectasia; NSAID: Nonsteroidal anti-inflammatory drug.