Aqueous intradermal low-dose house dust mite immunotherapy in tropical settings: a valid cost-effective approach for developing nations?

Abstract

Introduction: Aqueous allergen injections, an effective and century-old technique, is considered a second-line approach in daily clinical practice. Inconveniences still surround conventional subcutaneous immunotherapy (SCIT) administration, such as a need for frequent injections, prolonged up-dosing schedules, elevated costs, and the unlikely possibility of a systemic reaction. The intradermal immunotherapy route (IDR) might favorably impact many of the aforementioned issues (Table 1). House dust mite (HDM) allergens are the main perennial sensitizers in the tropics, and as such, are solely employed in immunotherapy treatments. Methods: We carried out a year-long real-life study in 25 perennial allergic rhinitis children, symptomatic on exposure to house dust, employing an intradermal low-dose allergen mix consisting of 50 ng of Dermatophagoides pteronyssinus/Dermatophagoides farinae and 120 ng of Blomia tropicalis, under a unique cost-wise protocol. Basal symptoms/signs and face Visual Analog Scale (fVAS) scores were recorded for 2 weeks and later compared with those registered throughout the 1-year treatment. Serum-specific IgG4 and IL-10 levels were employed in the assessment of the immune responses.Results: Symptoms/signs and fVAS scores were significantly reduced from days 42 and 49, respectively, and remained so until treatment completion. Increases in specific IgG4’s and IL-10 levels reflected significant immune responses. Injections were well tolerated and families reported improved health status (quality of life, QoL).Conclusions: A unique cost-effective immunotherapy alternative for deprived allergic communities in tropical settings is depicted; further research is needed.

Intradermal Allergen Immunotherapy for Allergic Rhinitis: Current Evidence

“…However, among the studies, some conflicting evidence has been reported. Three observational studies, two of which were published by Phillips in the early 20th century [ 30 , 31 ], and a recent study by Rondon et al [ 34 ], suggested the benefit of IDIT relative to symptom improvement. However, those three studies did not include control subjects, which makes it impossible to exclude the possibilities of a placebo effect.…”

“…Following the publishing of a pilot study by Hernández et al [ 33 ] that reported a reduction in the total nasal symptom score (TNSS) and the face visual analog scale (fVAS) in eight children with allergic rhinitis treated with IDIT, Rondon et al [ 34 ] recently published a study on IDIT in children diagnosed with perennial allergic rhinitis and a house dust mite (HDM) allergy. Interestingly, instead of using the usual allergen extracts, the authors prepared a flask containing a mixture of Dermatophagoides pteronyssinus / Dermatophagoides farinae and Blomia tropicalis and injected 0.05 mL of the mixture intradermally (approximately 8 AU of Dermatophagoides pteronyssinus / Dermatophagoides farinae and 0.12 mcg of Blomia tropicalis ).…”

New approaches to immunotherapy in house dust mite allergy

“…This is a pivotal issue that will help to overcome the limited technology available for the development of vaccines required for treating patients afflicted with allergies. 42,43) Moreover, continuous efforts are required to approach newer concepts, in particular, the discovery of a novel tool based on severity of the allergy and personal therapy. Exosomes are small vesicles (10-150 nm) secreted from several types of cells to extracellular environment, and include mRNA, lipids and proteins activating target cell function.…”

Update on pathomechanisms and treatments in allergic rhinitis

“…Intradermal immunotherapy (IDIT) and epicutaneous immunotherapy (EPIT) are different routes for administering the allergen through the skin. Compared to traditional allergen administration routes, IDIT and EPIT have many benefits, such as shorter treatment duration, lower allergen dose, and no need for adjuvants 113 . Rhinoconjunctivitis patients sensitized to grass pollen and receiving IDIT have been shown to have reduced clinical symptoms, medication consumption, and IgE levels, 114 with the improved clinical effects lasting for up to 2 years 115 .…”

“…Compared to traditional allergen administration routes, IDIT and EPIT have many benefits, such as shorter treatment duration, lower allergen dose, and no need for adjuvants. 113 Rhinoconjunctivitis patients sensitized to grass pollen and receiving IDIT have been shown to have reduced clinical symptoms, medication consumption, and IgE levels, 114 with the improved clinical effects lasting for up to 2 years. 115 Peanut-allergic children (aged 4-11 years) have also been shown to respond to EPIT with a peanut patch; however, the clinical effect of the patch remains to be fully determined.…”