J. Georgsen

Influence of radiographic contrast media on granulocyte enzymes and complement during uncomplicated urographies

Four different radiographic contrast media (RCM) were used for i.v. urography in 40 patients, none of whom had complications. No rise in C3d was observed for any of the RCM, indicating that complement was not activated. However, significantly decreased values for CH50 were detected when the non-ionic RCM iopamidol and iohexol were used, and this may be due to interaction between the RCM and the complement molecules. Significantly increased numbers of neutrophils were observed in patients receiving ioxaglate, iohexol and diatrizoate, which may be due to inhibition of granulocyte adherence. No rise in the concentration of elastase and lactoferrin was observed. On the other hand, significantly decreased values of elastase were seen after injection of diatrizoate, which may be due to inhibition of the degranulation process by this media.

Granulocyte adherence is inhibited by radiographic contrast media in vitro.

Different amounts of diatrizoate, ioxaglate, iohexol, iodixanol, NaCl 1000 mOsm/kg, mannitol 1098 mOsm/kg, and meglumine (meglumine concentrations corresponding to the content in the diatrizoate solutions) were added to either whole blood or a suspension of granulocytes in autologous plasma, and the adherence to nylon fibers was determined. At high concentrations all the investigated contrast media (CM) inhibited granulocyte adherence. The degree of inhibition was significantly greater when the ionic CM diatrizoate and ioxaglate were used, as compared with the nonionic media. Meglumine solutions at high concentrations also inhibited adherence but significantly less than diatrizoate solutions containing the same amount of meglumine. Diatrizoate showed the greatest inhibitory effect on granulocyte adherence, and significant inhibition could be detected even with a 1.25% solution.

Granulocyte enzymes and complement after an anaphylactoid reaction to coronary angiography.

An anaphylactoid reaction following angiography with ioxaglate in a 59-year-old man implied generalized pruritus, angioedema, bronchospasm and hypotension. Leucocytosis and an increased number of neutrophils were observed from 90 min to 8 h after the reaction. Elevated values of the neutrophil specific enzymes elastase and lactoferrin were demonstrated. The concentrations of C3d and CH50 did not change which indicate that no complement activation took place.

Granulocyte chemotaxis : influence of radiographic contrast media on the chemoattractive properties of serum

One of the important functions of granulocytes is the ability to respond to a chemoattractive signal by migration. The influence of radiographic contrast media (CM) on the chemoattractive properties of serum was investigated by under agarose technique for chemotaxis. No chemotactic response was seen when serum was incubated with different concentrations of CM after heat inactivation. The CM did not generate the heat stable complement split product C5a-desarg which would have resulted in a chemotactic response. Without heat inactivation all complement available in the serum was activated by the agarose in the chemotaxis assay. Low concentrations of iohexol and iodixanol brought about an increased chemotactic response relative to a reference with saline instead of CM. This may be due to activation of heat labile chemoattractants from other sources than the complement cascade. At high concentrations of all five investigated CM, a decreased number of granulocytes migrated over a shorter distance when compared with the reference, and this may be due to interactions between the CM and chemoattractants or their precursors.

Granulocyte chemotaxis. Chemoattractive properties of a synthetic tripeptide are inhibited by radiographic contrast media.

The under agarose method for evaluation of leucocyte chemotaxis was used to investigate the effect of radiographic contrast media (CM) on granulocyte locomotion. The CM tested had no chemoattractive properties. CM inhibited N-fmlp, a synthetic formylated Met-tripeptide, which is a strong chemotactic agent and an analogue to chemotatic peptides produced by bacteria. The inhibition of N-fmlp was most pronounced for diatrizoate. Equiosmolal saline was not so inhibitive. Therefore, some part of the inhibition was caused by factor(s) other than hyperosmolality inherent in the CM solution.

Phagocytic Properties of Granulocytes after Intravenous Injection of Ioxaglate or Iohexol

To evaluate the influence of radiographic contrast media (CM) on human granulocytes, the ability of these cells to ingest latex particles after intravenous injection of ioxaglate and iohexol was investigated. Both CM inhibited the phagocytic properties of granulocytes; the inhibition was the most pronounced immediately after the injection, but inhibition was also observed 60 min after injection of ioxaglate. The inhibition 1 and 5 min after injection of CM was more pronounced after injection of ioxaglate than after injection of iohexol. However, this difference between the 2 CM was not significant. Significant inhibition of phagocytosis was found for mannitol solutions with osmolalities higher than 369 mOsm/***1. Significant inhibition of phagocytosis was observed when granulocytes were isolated with either Hypaque/Ficoll or Percoll gradient centrifugation and then incubated with diatrizoate. Thus the ability of granulocytes to phagocytize latex particles was inhibited after i.v. injection of 50 ml ioxaglate or iohexol. Part of this inhibition may be due to hyperosmolality.

Radiographic contrast media and release of neutrophil specific proteins in vitro and after intravenous injection

The neutrophil granulocytes contain granules in which different proteins are present. When activated the neutrophils degranulate and thereby release some of these proteins to the surroundings. Some of these proteins are specific for this type of cell, e.g., lactoferrin and elastase. To investigate the influence of contrast media (CM) on this release, blood was incubated with diatrizoate, ioxaglate, iohexol, iodixanol, hyperosmolar saline, and hyperosmolar mannitol at different concentrations, and the amount of the neutrophil specific proteins lactoferrin and elastase were measured. Decreasing protein concentrations were observed for increased medium concentrations, suggesting that the degranulation process of the neutrophils was inhibited by the CM. The protein concentrations were lowest after incubation with the two ionic media diatrizoate and ioxaglate. Significantly decreased values of plasma lactoferrin were observed one min after i.v. injection of iohexol or ioxaglate in 82 patients undergoing urography. There was no significant difference between the two CM.

Granulocyte Chemotaxis before and after Urography Influence of Four Different Radiographic Contrast Media

Granulocytes isolated from whole blood of 10 volunteers with Hypaque/Ficoll or Percoll gradient centrifugation showed a significant inhibition of their chemotactic response when incubated with diatrizoate. The influence of 4 different i.v. injected radiographic contrast media (CM) on granulocyte chemotaxis was evaluated using the under agarose assay. Each CM was injected in 10 consecutive outpatients referred for urography. Cells and serum were obtained before and 20 min after the injection of CM. Autologous serum was used as chemoattractive agent, and the cell suspensions from both samples were tested against serum drawn both before and after the injection of CM. No significant changes in granulocyte chemotaxis or the chemotactic potential of serum were seen. Furthermore, there was no change in the chemotactic response towards homologous serum or N-fmlp after injection of diatrizoate or iohexol. In conclusion, the investigation did not unveil any change in granulocyte chemotaxis 20 min after the injection of CM in the 40 subjects studied.

Granulocyte adherence after intravenous and intraarterial injection of ioxaglate or iohexol

The effect of iohexol and ioxaglate on granulocyte adherence to nylon fibers was investigated with blood from 15 patients undergoing angiography, and from 24 patients undergoing excretory urography. Decreased adherence and increased numbers of granulocytes in the circulation were observed soon after injection of iohexol or ioxaglate in the aorta, or injection of ioxaglate i.v. Increased adherence and decreased numbers of granulocytes in the circulation were observed soon after injection of iohexol i.v. The differences were small soon after the injection of contrast media (CM). More pronounced decreased adherence and increased numbers of granulocytes were detected 2 and 5 hours after injection in the aorta for both CM.

On the inheritance of the Era red cell antigen

On the inheritance of the EP red cell antigen To the Editor: The E P antigen is established and has the number 019 in the 900 series (ISBT numerical designations).’ Individuals with the Er( a-) phenotype have been described in four fa mi lie^,^.^ but no definite conclusions about the mode of inheritance of the Er(a-) phenotype have been possible. Daniels et aL2 made two suggestions: a rare recessive gene at the Er locus or a dominant inhibitor of the Er“ gene. They pointed out that study of more families with an Er(a-) member was likely to resolve this problem. We investigated a large Danish kindred with an Er(a-) proposita; in this family a recessive trait seemed most likely. The proposita was a 71-year-old woman who had been pregnant six times (five normal deliveries and one miscarriage) and transfused on three occasions in the period 1955 to 1975. One unit of blood (1966) was followed by shivering and fever (39.8OC). On admission an antibody screening test was positive and the patient’s serum reacted with all red cells except her own by indirect antiglobulin and enzyme techniques. Red cells lacking the antigens Buckalew, Ch, Coa, Cra, Ge, Hy, J M H , Joa, Jra, Kpb, Lan, Lub, Lu8, Lu12, Rg, U, Vel, and Yta were incompatible. The serum from our patient was compatible only with red cells from a propositus who is Er(a-).2 The anti-Era from this propositus did not react with the red cells of our patient. Therefore, we concluded that our patient was Er(a-) and had anti-Era in her serum. Our findings were confirmed by the Quebec City Transfusion Centre, Canada.