Carboxymethylcellulose allergy as a cause of suspected corticosteroid anaphylaxis

Carboxymethylcellulose excipient allergy: a case report

Background

Excipients are widely used in pharmaceuticals, detergents, food, and drink because of their properties of low toxicity and hypoallergenicity. The excipient carboxymethylcellulose is used extensively as a thickener in foods such as baked goods, ice cream, gluten free, and reduced fat products, where it may be labeled as e-number E466. However, excipients can rarely cause type 1 hypersensitivity reactions. Several publications have described systemic allergy following carboxymethylcellulose exposure in pharmaceuticals, particularly systemic corticosteroids. Furthermore, there is one reported case in the literature of anaphylaxis following food containing carboxymethylcellulose.

Case presentation

We identify a case of anaphylaxis in a 45-year-old atopic Caucasian woman on receiving an injectable suspension of the corticosteroid triamcinolone acetonide containing carboxymethylcellulose, and subsequent allergic symptoms on reexposure to carboxymethylcellulose in a commercial drink. Diagnosis of carboxymethylcellulose excipient allergy was confirmed through skin prick testing using Celluvisc carmellose 0.5% eye drops, which contain carboxymethylcellulose as the active ingredient.

Conclusion

This case highlights the importance of identifying excipients such as carboxymethylcellulose as causes of allergy, to reduce burden of further hypersensitivity reactions, not just to drugs but to other consumables.

Hypersensitivity reactions to corticosteroids

PURPOSE OF REVIEW

To describe the clinical entities, underlying mechanisms and diagnostic approach of hypersensitivity reactions to corticosteroids, emphasizing new data concerning hypersensitivity reactions to systemically administered corticosteroids.

RECENT FINDINGS

Reactions after topical corticosteroid administration to the skin have been known for decades, appearing as an eczematous lesion and with diagnosis by patch testing. However, new data have appeared about cutaneous symptoms after inhaled and systemically administered corticosteroids. In fact, T-cell involvement in a generalized maculopapular exanthema induced by inhaled budesonide has recently been demonstrated by lymphocyte transformation tests. Moreover, T-cell involvement has also been shown in skin biopsies from a group of patients with urticaria and maculopapular exanthema after systemically administered corticosteroids, with detection of a significant increase in the expression of interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha), and a significant decrease in interleukin-4 and GATA-3 when samples obtained during the drug provocation test reaction were compared with samples from the resolution phase. In immediate allergic reactions to corticosteroids, an immunoglobulin E (IgE) response has recently been shown by skin testing, ImmunoCAP and basophil-activation tests.

SUMMARY

Generalized cutaneous symptoms after corticosteroid administration occur with both IgE and T-cell involvement. Skin testing, in-vitro testing and drug provocation tests are useful diagnostic tools.

Contact Urticaria from Carboxymethylcellulose in White Chalk

BACKGROUND

Carboxymethylcellulose (CMC) is widely used in consumer goods, foods, and medicaments as a binder, emulsifier, and viscosity enhancer. Cases of immediate and delayed allergic reactions to this anionic cellulose polymer have been reported.

OBJECTIVE

To report a case of contact urticaria from CMC in chalk, with possible cross-reaction to methyl hydroxyethylcellulose (MHEC).

METHOD

Patch tests with readings at 48 and 96 hours were performed with the North American Contact Dermatitis Group standard series and benzisothiazolinone. Open and prick tests with readings after 30 minutes were performed with two brands of chalk as well as with various petrolatum and aqueous dilutions of CMC, MHEC, oleic acid, and calcium carbonate.

RESULTS

The patient developed strong urticarial reactions during open tests with both powdered chalks and had milder reactions to the open test with CMC 10% aqueous (aq) and to prick testing with CMC 0.1% aq. No reaction to MHEC or any of the other ingredients of the chalks was observed. No relevant delayed reaction was noted.

CONCLUSION

CMC can cause contact urticaria. It remains unclear why our patient reacted more strongly to the chalk than to CMC itself. We speculate that the abrasive nature of the chalk enhances the cutaneous penetration of CMC or that calcium carbonate, the main ingredient of the chalk, acts as an adjuvant. It is also possible that CMC and MHEC cross-react and that our negative results with MHEC may be due to improper testing technique or concentrations.

Immunoglobulin E-mediated reactions to corticosteroids

Allergic reactions to steroids are rare, but are becoming more commonly recognized by clinicians. Although many reactions are thought to be IgE mediated, most are adverse drug reactions caused by nonallergic mechanisms, some related to additives in the steroid preparation being administered. Provocative challenge with the suspected offending agent, serologic tests for allergen-specific IgE, and skin testing are the most reliable methods for assessing hypersensitivity to steroids, although none is infallible. Therapeutic options for patients with documented steroid allergy include the use of alternative steroid preparations, desensitization, and, possibly, the use of monoclonal anti-IgE antibodies.