Sami L. Bahna

Allergic reactions associated with sexual activity are under-recognised and have been primarily attributed to vaginal contact with seminal glycoprotein or a contaminating drug or food. The authors describe a case of anaphylaxis in a woman following oral contact with her husband’s semen, despite having previously tolerated such exposure without adverse reactions. This incident occurred while the husband was receiving cephalexin therapy. She has a history of respiratory allergy and urticaria to penicillin. The evaluation included skin testing with penicillin reagents, cefazolin solution, and her husband’s seminal plasma. The couple consented to further investigation by having the husband taking cephalexin for 2 days, and the drug level was measured in his serum, urine, and seminal plasma before and after administration. The wife’s skin test results were positive for penicillin but negative to cefazolin and her husband’s seminal plasma. Cephalexin was undetectable in the husband’s serum, urine, and seminal plasma samples obtained before the drug administration. Post-administration specimens showed high concentrations in the urine, followed by a lower concentration in the serum. However, the drug was below the detectable level in the seminal plasma (the assay’s sensitivity was 6.25 µg/mL). The patient was counselled regarding preventive measures whenever her husband takes penicillin or first-generation cephalosporins. To the best of the authors’ knowledge, this seems to be the first reported case of allergy in a woman with oral exposure to semen contaminated with cephalexin. Healthcare providers should be aware of allergic reactions associated with oral sex, and that the causative allergen may not be the seminal plasma glycoprotein but a contaminating drug or food. Other potential causes include environmental substances or factors related to intimate interaction.

Food allergic reactions primarily occur after exposure to the offending food through ingestion, contact, or inhalation. However, it can occur covertly through hidden ways that are often missed, with undesirable consequences. Information has been accumulating over the years to indicate that food allergy (FA) may have been the problem in subjects who do not report an association to eating, touching, or smelling a food. Therefore, it would be prudent to explore the possibility of a hidden FA. The causative substance may be a food allergen or a nonfood allergen hidden in a previously tolerated food. Food allergens are commonly hidden in various medications, even in anti-allergy drugs. A blood product may passively transmit food allergens to a recipient who is sensitized or food-specific immunoglobulin E antibodies to a recipient who is nonatopic. It may also be excreted in breast milk, saliva, or semen. Transmission of the FA genetic trait can occur through transplantation of hematopoietic tissue. When the medical history and routine allergy evaluation do not point to the cause of an allergic reaction, it would be prudent to suspect hidden FA before labeling the reaction as idiopathic. A skillful detailed history taking, a cooperative patient, a careful reading of labels, and an interested allergist are needed for suspecting hidden FA and for planning an appropriate evaluation and verification of the offending allergen and, ultimately, optimal relief for the patient.

As the prevalence of food allergies (FAs) increases worldwide, our understanding of their pathophysiology and risk factors is markedly expanding. In the past few decades, an increasing number of ge...

Introduction: The development of new biologic agents has provided definite therapeutic advances but, like with any new medications, safety remains a concern. Areas covered: Using PubMed, we reviewed the literature on the adverse effects (AE) to five biologics approved for asthma and/or allergic diseases: one anti-IgE (omalizumab), three anti-IL5 (mepolizumab, reslizumab, benralizumab), and one anti-IL4 (dupilumab). Expert opinion: Biologic agents approved for asthma and allergic diseases are generally safe. Most common AE are benign and tolerated, though long-term safety is lacking for most of them. A slightly increased risk of anaphylaxis to omalizumab and reslizumab required the inclusion of a black box warning, informing the patient, the need for post-injection observation period, and the provision of epinephrine autoinjectors for self-administration when needed. Hypersensitivity reactions, mainly urticaria and very rarely serum sickness have occurred.