| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 All authors: Department of Radiology, SL 54, Tulane University Health Science Center, 1430 Tulane Ave., New Orleans, LA 70112.
Received June 27, 2002;
accepted after revision August 13, 2002.
Address correspondence to B. M. Plavsic.
Abstract
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
MATERIALS AND METHODS. We studied 110 patients in a retrospective review. Diatrizoate meglumine and diatrizoate sodium for abdominal CT were administered to 98 of these patients; 22 of the 98 had also been given the same contrast medium administered by enema. The remaining 12 patients were given diatrizoate sodium for gastrointestinal fluoroscopy. A control group of 65 patients underwent single-contrast barium upper gastrointestinal or enema examinations. WBC and eosinophil counts were determined approximately 24 hr before the examination and every 24 hr thereafter, through the ninth day.
RESULTS. Eosinophilia was detected in 17 (15.5%) of 110 patients after gastrointestinal administration of iodinated contrast media. The prevalence of eosinophilia after administration of iodinated contrast media was statistically significantly different compared with that in the control group, in which none of the 65 patients had eosinophilia (p < 0.001). Eosinophilia was detected 48 hr after application of iodinated contrast agents and lasted through the sixth day, with a peak on the fifth day. The prevalence of eosinophilia was independent of route of application, dose, or type of iodinated contrast medium. Eosinophilia in all cases was clinically asymptomatic.
CONCLUSION. Eosinophilia that is caused by gastrointestinal administration of iodinated contrast media is a transient, clinically silent phenomenon. It may lead to unnecessary workup for known conditions associated with eosinophilia.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
To our knowledge, peripheral blood eosinophilia occurring after gastrointestinal administration of iodinated contrast media has not been reported. We set out to test the hypothesis that eosinophilia may develop after oral, rectal, or combined oral and rectal administration of iodinated contrast media.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
The data were collected from the inpatient medical records of a single medical center from approximately 10 years. Fifty-seven of 110 patients in the experimental group and 33 of 65 patients in the control group were women. The age range in the experimental group was 18-79 years, and in the control group, 24-82 years.
Technique
Approximately 20 mL of a diatrizoate meglumine and diatrizoate sodium
solution (MD-Gastroview, 367 mg I/mL; Mallinckrodt, St. Louis, MO) diluted
with 300 mL of water were administered orally to a group of 98 patients for
abdominal CT. Twenty-two of those patients were also given an enema of
comparable volume of the same contrast medium diluted equally with water.
Twelve patients were given various smaller or larger amounts of diatrizoate
sodium (Hypaque Sodium, 600 mg organically bound iodine per gram of powder;
Nycomed, Princeton, NJ) dissolved in water for fluoroscopy: three for an upper
gastrointestinal series and nine for enemas.
A control group of 65 patients underwent single-contrast barium sulfate upper gastrointestinal (30 patients) or barium enema examinations. None of these patients was given IV iodinated contrast medium.
WBC and differential counts were reviewed 1 day before the examinations and at 24-hr intervals thereafter. In most patients, blood specimens were drawn in the morning, usually between 8:00 A.M. and 10:00 A.M. The number of eosinophils was expressed in thousands per microliter, and normal values were 0.05-0.55 x 103/µL. The patients had multiple blood counts done for various diagnoses, none of which was related to conditions known to cause eosinophilia.
Statistical Analysis
The percentage of patients with eosinophilia was calculated for both the
group receiving iodinated contrast media and the control group. We used the
chi-square test to determine the statistical significance of the difference in
prevalence of eosinophilia in the two groups and considered the level of
statistical significance to be a p value of less than 0.01. The
degree of uncertainty associated with proportions was quantified using 95%
confidence intervals calculated with the method described by Berry
[4].
We then calculated the arithmetic mean and the standard error of the arithmetic mean of the absolute numbers of eosinophils for the group of patients who were given iodinated contrast media and for the control group. The significance of differences between the two groups was tested at each 24-hr interval using the Student's t test. The significance level was p less than 0.01.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Eosinophilia was detected approximately 48 hr after the application of iodinated contrast media. The absolute number of eosinophils peaked on the fifth day at 0.83 ± 0.2 x 103/µL (Fig. 1). The increase in the eosinophil count in these patients was statistically significant compared with the count in the control group. The number of eosinophils was normal on the sixth day. On the seventh and eighth days, the number of eosinophils was elevated in the group who had been given iodinated contrast media; however, compared with the control group, the difference was not statistically significant (p > 0.02 on day 7 and p > 0.01 on day 8). The patients were clinically asymptomatic when eosinophilia was present.
|
The prevalence of eosinophilia was independent of oral (12/79 patients with eosinophilia; 15.2%) or rectal (1/9 patients with eosinophilia; 11%) routes of administration (p > 0.10). The eosinophil counts in patients receiving different doses of the same iodinated contrast medium were compared at 5 days after oral administration of MD-Gastroview (20 mL to each of 76 patients) versus oral and rectal administration (40 mL to each of 22 patients). At 5 days, the number of eosinophils in the group who had been given 20 mL of contrast medium was 0.80 ± 0.16 x 103/µL compared with 0.82 ± 0.19 x 103/µL in the group who had been given 40 mL. The difference was not statistically significant (p > 0.20). We found no significant difference in prevalence of eosinophilia when we compared the groups receiving the various iodinated contrast media (with MD-Gastroview for CT: 15/98 patients, 15.3%; with Hypaque for fluoroscopy: 2/12 patients, 16.6%) (p > 0.90).
No changes in total WBC count occurred in either the group receiving iodinated contrast media or the group who were given barium suspension.
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
At its peak, the absolute number of eosinophils was approximately 1.5 times higher than the upper limit of the normal value; some patients had eosinophil counts almost twice the normal level. In parasitic infestations, known for high eosinophil counts, the number of eosinophils may be a multiple of normal values. The maximal number of eosinophils did not exceed 1.03 x 103/µL in our patients who had gastrointestinal administration of iodinated contrast media. Therefore, gastrointestinal administration of iodinated contrast would be an unlikely explanation for much higher eosinophil counts.
When we compared the eosinophil counts in patients who were given contrast media by oral administration with those of patients who had rectal administration, no difference was found. The increase in the number of eosinophils was independent of dose or type of iodinated contrast medium. Other contents of the contrast agents, as opposed to iodine, have not been reported to cause eosinophilia. The incidence of eosinophilia after IV application is similarly independent of dose or type of iodinated contrast medium [2].
Previous results indicate that oral administration of diatrizoate sodium results in absorption of iodine [5]. One hour after administration of a diatrizoate sodium enema, a patient's serum iodine levels increase 10- to 200-fold. The dose of contrast medium administered appears to have no relationship to the maximal serum iodine levels [5]. The presence of iodine in the blood after enteral administration of iodinated contrast media may explain the eosinophilia in our patients. Eosinophilia results from increased release of eosinophils from the bone marrow or other tissues. The production of eosinophils may or may not be increased. More than 100 times as many eosinophils are found in the tissues as in the blood, particularly in organs with an interface with the environment, such as the gastrointestinal tract [6,7,8]. The emergence time from bone marrow to blood is between 18 and 40 hr. Eosinophils persist in the circulation with a half-life of 6-12 hr and then enter the marginated pool or migrate to the tissues to complete their life cycle of 8-10 days [6, 9, 10]. We have documented eosinophilia on the second day after gastrointestinal administration of iodinated contrast medium that lasted through the sixth day.
The number of eosinophils is independent of the count of other leukocytes, suggesting an autonomous control mechanism. We noticed no change in total WBC after administration of the contrast media. Interleukin-5 induces a production of eosinophils in the bone marrow that peaks at approximately 3 weeks and also acts as a chemotactic factor for eosinophils in the tissues [9,10,11]. Evidence exists that eosinophilia is T-cell dependent; the Th2-type cell secretes interleukin-4 and interleukin-5 [7, 12, 13]. Eotaxin, another potent chemoattractant for eosinophils, is produced by epithelial and phagocytic cells and stimulated by interleukin-4 [14].
We have observed a relatively rapid response of eosinophil count to gastrointestinal administration of iodinated contrast media. However, in this retrospective study, serum concentrations of interleukins or eotaxin were not measured. The increased number of eosinophils may have consisted of cells prematurely released from the marrow or cells that were demarginated; it is also possible that a mechanism causing recirculation of eosinophils outside the bone marrow could have been triggered by iodine. On the seventh and eighth day after iodinated contrast material administration, the number of eosinophils was moderately elevated, but the difference in eosinophil count was not statistically significant between these patients and those in the control group. This second peak may have resulted from recirculation of iodine; however, the iodine levels were not measured in this study.
Whichever mechanism may have led to it, eosinophilia is frequently a relevant indicator of various clinical abnormalities [9, 15]. The main practical significance of eosinophilia associated with iodinated contrast media is that it must be differentiated from other conditions associated with an elevated eosinophil count. Iodinated contrast media are commonly administered to a considerable population of patients via the gastrointestinal system. Eosinophilia induced by the administration of an iodinated contrast agent may lead to unneeded workup to evaluate for allergic hypersensitivity, reactions to medication, parasitic and connective tissue diseases, certain neoplasms, and hypereosinophilic syndromes [15, 16].
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
 |
|
  T. Koga and H. Aizawa Iatrogenic Eosinophilia Arch Intern Med, January 12, 2004; 164(1): 106 - 106. [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
) and
in control group (
). Circles and squares represent arithmetic means;
vertical bars represent standard errors of arithmetic means.