Anaphylaxis to clindamycin following cutaneous exposure

Background

The role and importance of skin barrier as an immunologic organ and as a potent way of sensitization is well known. However, antibiotics anaphylaxis following skin sensitization has not been reported.

Case presentation

We describe the first case of intravenous clindamycin anaphylaxis, with likely sensitization due to previous topical exposure to clindamycin gel for acne in a 14-year-old boy with history of atopy and mild atopic dermatitis.

Conclusion

This case highlights the potential sensitization to drug allergens, including antibiotics, via the skin.

Consultation with registered dietitian to prevent accidental reactions to food: insight from an egg allergy influenza vaccination cohort

Egg is an ubiquitous allergen found in many food products. Current food allergy guidelines recognize the importance of consultation with a registered dietitian to ensure nutritional adequacy. However, there is a lack of evidence on its impact on the implementation of allergen avoidance strategies. Taking advantage of a well-characterized cohort of influenza vaccination in egg-allergic children (n=397), we tested the hypothesis that real-life professional dietary advice was associated with a decrease in accidental reactions to egg in allergic children with retrospective questionnaires. Lack of consultation with a dietitian was associated with a 1.89-fold increase in the risk of accidental reactions to egg (confidence interval: 1.47-2.42). The only other independent variable that predicted reactions was having had a history of acute reaction to egg prior diagnosis (relative risk=2.02; confidence interval: 1.64-3.00). These findings support the usefulness of referral to a food allergy-specialized dietitian at time of diagnosis in order to prevent future accidental reactions to egg.

Introduction of peanuts in younger siblings of children with peanut allergy: a prospective, double-blinded assessment of risk, of diagnostic tests, and an analysis of patient preferences

BACKGROUND

The prevalence of peanut allergy in younger siblings of children with peanut allergy has been reported between 7% and 8.5%, but the anaphylactic risk at the time of introduction is currently unknown, which limits our ability to best counsel parents on this issue.

OBJECTIVE

To determine the risk of anaphylaxis and working parameters of allergy testing in this context.

METHODS

One hundred and fifty-four peanut-naïve younger siblings of peanut-allergic children underwent double-blinded skin testing, followed by parent-led peanut introduction. Questionnaires were dispensed to parents to investigate preferences with regard to peanut introduction in this subgroup.

RESULTS

Eight participants (5.2%) presented unequivocal IgE-mediated reactions to peanut upon introduction, including five anaphylaxes. These participants were significantly older compared to the rest of the cohort (median 4.0 vs 1.9 years, P = 0.04). The negative predictive value of skin prick test with peanut extract and peanut butter and of specific IgE was 99%, 100%, and 100%, respectively. Six peanut-tolerant participants had positive peanut allergy tests. The option of introducing at home without prior skin testing was associated with high levels of anxiety (median 8.4 on 10-point Likert scale) when compared to supervised introduction (median 3.8, P < 0.0001) or home introduction after negative skin test (median 4.3, P < 0.0001).

CONCLUSIONS

There is an increased risk of anaphylaxis upon peanut introduction in siblings of children with peanut allergy, and parents are reluctant to introduce at home without testing. Allergy testing prior to introduction is negative in over 90% of cases and carries a high negative predictive value.

Rhinosinusitis in severe asthma

BACKGROUND

Chronic rhinosinusitis is a common comorbidity of asthma. However, sinonasal involvement in severe steroid-dependent asthma is still undefined.

OBJECTIVE

The aim of the study was to evaluate chronic rhinosinusitis in 35 patients with severe steroid-dependent asthma by using a clinical score and coronal computed tomography (CT) scanning.

METHODS

Thirty-five subjects (16 female subjects) with severe asthma requiring daily doses of oral corticosteroids were compared with 34 patients (19 female patients) with mild-to-moderate asthma. Sinonasal involvement was studied by using clinical and CT scores. Airflow obstruction, therapy requirement, and asthma triggering factors were carefully assessed.

RESULTS

The proportion of patients with symptoms of rhinosinusitis was similar in both groups of asthmatic subjects (74% in patients with severe steroid-dependent asthma and 70% in patients with mild-to-moderate asthma). All subjects with steroid-dependent asthma versus 88% of subjects with mild-to-moderate asthma had abnormal CT scan results. The clinical (P <.05) and CT scan (P <.0005) severity scores were higher in the subjects with severe steroid-dependent asthma. In both groups the CT scan scores were correlated to the clinical scores (P <.0001 and P <.006), but only in the mild-to-moderate group were both scores correlated with high significance (P <.002 and P <.0005) to the absolute number of blood eosinophils.

CONCLUSION

Frequency of rhinosinusitis in patients with mild-to-moderate or severe steroid-dependent asthma is similar; however, sinonasal involvement, as evaluated by clinical symptoms and CT scan imaging, is significantly greater in the patients with severe steroid-dependent asthma than in those with mild-to-moderate asthma.

Immunotherapy with a standardized Dermatophagoides pteronyssinus extract. VI. Specific immunotherapy prevents the onset of new sensitizations in children

BACKGROUND

The natural history of allergic sensitization is complex and poorly understood. A prospective nonrandomized study was carried out in a population of asthmatic children younger than 6 years of age whose only allergic sensitivity was to house dust mites (HDMs).

OBJECTIVES

The study was designed to determine whether specific immunotherapy (SIT) with standardized allergen extracts could prevent the development of new sensitizations over a 3-year follow-up survey.

METHODS

We studied 22 children monosensitized to HDM who were receiving SIT with standardized allergen extracts and 22 other age-matched control subjects who were monosensitized to HDM. The initial investigation included a full clinical history, skin tests with a panel of standardized allergens, and the measurement of allergen-specific IgE, depending on the results of skin tests. Children were followed up on an annual basis for 3 years, and the development of new sensitizations in each group was recorded.

RESULTS

Ten of 22 children monosensitized to HDM who were receiving SIT did not have new sensitivities compared with zero of 22 children in the control group (p = 0.001, chi square test).

CONCLUSIONS

This study suggests that SIT in children monosensitized to HDM alters the natural course of allergy in preventing the development of new sensitizations.

Long-term oral corticosteroid therapy does not alter the results of immediate-type allergy skin prick tests

BACKGROUND

Medications can modulate the results of skin prick tests (SPTs). Short-term corticosteroid therapy does not alter IgE-mediated skin tests, but the impact of long-term oral corticosteroid therapy on SPT results is unclear. A prospective study was carried out in patients with steroid-dependent asthma who received oral corticosteroids for a long period to determine whether this treatment reduced skin test reactivity.

METHODS

Thirty-three patients with steroid-dependent asthma (median age, 59 years) were compared with 66 patients with asthma who served as a control group, matched for age, sex, and atopic status. SPTs with codeine phosphate and a screening battery of standardized allergen extracts were performed before commencement and after at least 1 year of daily oral prednisone treatment (median duration, 2 years; median daily dose, 20 mg).

RESULTS

Fifteen patients with corticosteroid-dependent asthma were allergic before treatment, and their sensitization was not changed by long-term treatment with oral corticosteroids. The median wheal diameters induced by codeine phosphate were similar in both groups. The median wheal diameters induced by allergens, and more specifically, by Dermatophagoides pteronyssinus and D. farinae were similar in both groups and did not change in the steroid group after treatment.

CONCLUSIONS

Systemic corticosteroid therapy (prednisone, 10 to 60 mg/day) for 2 or more years does not seem to alter SPT reactivity.

Immunotherapy with a standardized Dermatophagoides pteronyssinus extract. V. Duration of the efficacy of immunotherapy after its cessation

Specific immunotherapy (SIT) using a standardized mite extract is effective and safe when administered under optimal conditions. However, the duration of its effectiveness after cessation of treatment remains unknown. Forty asthmatic subjects who had received SIT with a standardized Dermatophagoides pteronyssinus (Der p) extract under the same protocol were studied. All had received SIT for a period of 12-96 months and were not receiving pharmacologic treatment. The FEV1 was within normal range in all patients. After cessation of treatment, patients were followed for up to 3 years at 6-month intervals. The patient was considered to have relapsed when symptoms of asthma and/or rhinitis occurred and/or when pulmonary function tests were impaired. Skin tests with increasing concentrations of Der p were carried out before and at the end of SIT. Forty-five percent of the patients did not relapse. The duration of efficacy of SIT was related to the duration of SIT itself (P < 0.04). Most patients who did not relapse had a decrease in skin test reactivity at the end of SIT, whereas most patients who relapsed did not show any change (P < 0.003). The duration of efficacy of SIT after its cessation depends upon the duration of SIT and may be predicted by the effect of SIT on skin tests.