Local Hypersensitivity Reactions Research Articles

Effect of Polysaccharides Isolated from Saussurea salicifolia (L.) DC on Th2-Dependent Immune Response.

The effect of polysaccharides isolated from the aboveground parts of Saussurea salicifolia (L.) DC on Th2 type immune response reactions was studied. Administration of water-soluble polysaccharides presented by arabino-galacturonans (weight average molecular weight 158.49 kDa) to mice against the background of experimental Th2 immunity reduced the severity of anaphylactic and local immediate type hypersensitivity reactions. It also suppressed the production of ovalbumin-specific IgE and IgG1 and increased the stability of mast cell membranes. The studied polysaccharide complex increased IFNγ secretion and inhibited IL-4 synthesis. These findings suggest that these polysaccharides may be considered as potential anti-allergic agents that suppress the development of allergy in its early stages.

Tick-borne diseases at the crossroads of the Middle East and central Europe

ObjectivesThe Balkan Peninsula, acting as a crossroad between central Europe and the Middle East, presents diverse ecosystems supporting various tick species capable of transmitting TBDs. This study focuses on Serbia and North Macedonia, both endemic for TBDs, aiming to investigate human-biting ticks’ prevalence, TBD prevalence, and major TBPs in blood samples. Patients and MethodsThis prospective observational study was conducted in 2022 at two medical centers, involving 45 patients from Novi Sad, Serbia, and 17 patients from Skopje, North Macedonia. All participants had either a tick still attached or had had one removed within the preceding 48 h. The study consisted in clinical evaluations of patients and testing of patient samples and ticks for tick-borne pathogens using a High-Throughput pathogen detection system based on microfluidic real-time PCR. In addition, the study assessed the genetic diversity of the identified pathogens. ResultsIxodes ricinus was the most prevalent tick species, with varying infestation rates across various body parts. Tick species and feeding times differed between Novi Sad and Skopje. TBPs were prevalent, with Rickettsia spp. dominant in Skopje and a mix including Rickettsia aeschlimannii, Rickettsia monacensis, Anaplasma phagocytophilum, and Borrelia afzelii in Novi Sad. Subclinical bacteremia occurred in 8.06% of cases, mostly involving Anaplasma spp. Clinical manifestations, primarily local hypersensitivity reactions, were observed in six patients. Phylogenetic analysis confirmed R. aeschlimannii and R. monacensis identity, highlighting genetic differences in gltA gene sequences. ConclusionsThis study sheds light on the prevalence and diversity of TBPs in tick-infested individuals from Serbia and North Macedonia, contributing valuable insights into the epidemiology of TBDs in the Balkan region.

Transient synovitis associated with leuprolide depot (Lupron).

A 6.6-year-old female presented to endocrinology with precocious puberty for evaluation and management. Workup was initiated, and a diagnosis of central precocious puberty was confirmed. A decision was made to initiate pubertal blockade using gonadotropin-releasing hormone agonist (GnRHa) therapy with depot leuprolide acetate injections every 3 months. The patient received the first depot leuprolide acetate injection in the right ventrogluteal area. Six hours following the injection, the patient was reported to be inconsolable in pain, which was localized to the right hip site of the earlier injection and associated with a refusal to ambulate. The pain and discomfort continued to progress over the next 24 h despite an alternating regimen of Tylenol and ibuprofen prompting admission to the emergency department. Vital signs demonstrated a low-grade fever and elevated C-reactive protein. An ultrasound of the right hip demonstrated fluid accumulation within the joint. Over the next week, the patient was unable to walk independently and required assistance for activities of daily living. By 2 weeks after the injection, the pain began to remit, and the patient resumed activities of daily living. Following consultation with allergy, a decision was made to continue GnRHa suppressive therapy with an alternative analog (Triptodur). The patient tolerated subsequent treatment without reaction. Although gonadotropin-releasing hormone agonists (GnRHa) have a generally good safety profile, there is a history of both local and systemic hypersensitivity reactions associated with their use. Despite the long-acting formulation of depot leuprolide acetate, the systemic reaction in this case appears to be self-limited. Discontinuation of therapy or a change to an alternative formulation of GnRHa analog should be considered based on the need for therapy versus the potential risk of rechallenge.

Severely Painful and Pruritic Forearm Rash: A Case of Caterpillar Envenomation in South Florida.

The asp caterpillar (Megalopyge opercularis) is endemic to the southeastern United States, with most sightings in Florida, Texas, and Louisiana. A few hundred caterpillar envenomations are reported annually with most cases occurring in July-November. Asp caterpillars have hollow spines along their backs that contain venom. Contact with these spines is what produces the characteristic "sting" resulting in contact dermatitis and a localized hypersensitivity reaction collectively referred to as lepidopterism. Symptoms of lepidopterism may include severe burning pain, pruritis, edema, nausea, vomiting, abdominal pain, and headache. Symptoms are often self limited, and treatment should focus on expedited removal of implanted spines and aggressive symptom management. We present the case of a patient presenting to the emergency department (ED) with acute-onset severe left forearm pain with associated pruritic rash incurred while working in a retail store. Initial therapeutic management included administration of analgesics, antihistamines, and steroids. After obtaining a comprehensive history and consulting with the Poison Control Center, we suspected an asp caterpillar envenomation. Following extraction of the caterpillar spines with silk tape, the patient's symptoms improved. After a period of observation in the ED, the patient was discharged home without any known sequelae. Although asp caterpillars typically inhabit trees and foliage, human exposure to the caterpillar may occur in developed environments. Effective history-taking, prompt communication with toxicologic experts, and complete removal of intact spines are essential for early identification and effective clinical management of asp caterpillar envenomation.

Local Anesthetic Hypersensitivity Reactions in Pediatric Patients: Recognition and Management.

Local anesthetics (LAs) are commonly used in all medical specialties, particularly in association with surgery, obstetrics, dentistry, and emergency departments. Most individuals, starting from young children, are exposed to LAs during life. LA hardly induces adverse events when used in recommended doses and with proper injection techniques. However, immediate anaphylactic reactions to LA injections may be a rare but life-threatening manifestation. A comprehensive report of the event and performing a specialist examination are crucial to prevent further episodes. The diagnosis should be based on history, medical records, skin and challenge tests.

Updated beliefs and shaken confidence: evidence from vaccine hesitancy caused by experiencing “COVID arm”

BackgroundPublic health depends largely on people’s knowledge, beliefs, or behaviors regarding their health and medical treatments. Although works based on the health belief model have shown that public beliefs about medical treatments affect willingness to take the treatments, little is known about the effects of changes in beliefs on attitudes toward treatment. How one’s past experiences relate to one’s beliefs about a given medical treatment is worth considering.MethodsWe implemented an online panel survey in February 2021 and March 2022 in Japan before and after COVID-19 vaccines were administered to the public within the country. We exploited delayed localized hypersensitivity reactions to COVID-19 vaccines, namely, “COVID arm”, as an exogenous shock to investigate the relationship between past negative experiences and current beliefs about medical treatments or science. “COVID arm” was an unexpected side effect and thus likely caused updated beliefs about the vaccine. Out of the nonprobability sample of 15,000 respondents in the first wave in February 2021, 9,668 respondents also responded to the second wave conducted in March 2022. Outcome variables were whether experiencing “COVID arm” affected the respondents’ 1) confidence in vaccine safety, 2) willingness to take the next dose of COVID-19 vaccines, 3) acknowledgment of the importance of vaccination, and 4) confidence in science. We measured the impact of experience with “COVID arm” on changes in the probability that survey respondents would respond affirmatively to questions posed about the issues listed above.ResultsExperiencing “COVID arm” significantly lowered confidence in the safety of vaccination by 4.3 percentage points, which was approximately 6% of the sample mean for the first wave, and lowered the probability of taking a second dose of the COVID-19 vaccine by 1.5 percentage points. These adverse impacts were observed after conditioning background characteristics and prior confidence in vaccination. Experiencing “COVID arm” affected neither the acknowledged importance of vaccination nor confidence in science in a statistically significant way.ConclusionsAn unexpected and uncomfortable shock regarding beliefs about a treatment decreases willingness to take the treatment. An appropriate public health policy should account for this effect.Trial registrationThe survey was preregistered with the American Economic Association’s RCT Registry (Fukai et al., 2022).

The first successful desensitization protocol in exenatide allergy: a case report

BackgroundGlucagon-like peptide-1 (GLP-1) receptor agonists are important treatment options in obese patients with type 2 diabetes. To date, few immediate allergic reactions due to GLP-1 receptor agonists were reported. One report revealed that a patient with a level 1 anaphylaxis according to Brighton Criteria due to an exendin based GLP-1 receptor agonist was able to tolerate liraglutide (Human GLP-1 analogue), the alternative GLP-1 receptor agonist. Since exenatide is the only available GLP-1 receptor agonist covered by insurance in Turkey, a drug desensitization protocol, the only therapeutic method in hypersensitivity reactions used in case of absence of an alternative drug, was considered. Here, we report a successful desensitization protocol for the first time in two obese diabetic patients with an immediate hypersensitivity to exenatide.Case presentationThe first patient was a 47 year-old female. She was referred to our outpatient allergy clinic because of a generalized urticaria developed within minutes after the last dose, following a week of an exenatide BID 5 mcg/20 mcl treatment. Although the reaction was sudden onset, it did not meet the Brighton Criteria of anaphylaxis. The second patient was a 46 year-old female. She had a large local immediate injection site reaction that appeared 15 min following an exenatide BID 5 mcg/20 mcl injection. The injection site reaction was not accompanied by a systemic allergic reaction. We performed desensitization with exenatide to two patients who need GLP-1 receptor agonist treatment. Protocol was completed in 7 steps in approximately 3 h, with the aim of reaching the daily dosage of exenatide. Throughout this process, we observed that both cases tolerated the protocol without any complaints or complications. Following the protocol, the patients safely tolerated the treatment for 3 months.ConclusionsWe present the first successful desensitization protocol to exenatide in both local and/or systemic immediate hypersensitivity reactions and indicate the importance of desensitization in patients who do not have alternative therapies.

Delayed Localized Hypersensitivity Reactions to an Adenoviral Vector Vaccine—A Literature Review and A Case Report with Serial Ultrasonography Follow-Up

Delayed Localized Hypersensitivity Reactions to an Adenoviral Vector Vaccine—A Literature Review and A Case Report with Serial Ultrasonography Follow-Up

Evaluation of Post–vaccination Symptoms of COVID 19 Vaccines among People in Basrah- Iraq Society

Introduction: Vaccines are one of the most effective interventions for destroying COVID-19. Many organizationshave worked to establish an efficient and safe preparation in the minimum time possible. Currently, severalproducts that different in form and effectiveness are approved for sale.Objectives: The goal of this study was to obtain evidence on COVID-19 vaccination adverse effects.Methodology: A cross-sectional study was made between October and December 2021 to obtain data on theinfluence of the COVID-19 vaccine among people in the Iraq- Basrah. There were two types of questions listed.The first one covers the subject’s background information, such as nationality, gender, age, educational level, andpast COVID 19 infection. The second set of questions focused on information about the COVID-19 vaccines andtheir side effects.Result: Local site adverse reaction, Hypersensitivity reaction, bone and muscle pain, headache and fever weremore common in persons received second dose than in participant received first dose. There was a significantdifference in the number of people those under 60 years of age who reported fever, headache, bone and musclepain compared to those 60 years old and over.conclusion: The COVID-19 vaccine’s side effects are similar to those seen with earlier immunizations, and themost of them are tolerable.

Risk Factors for Immediate-Type Local Anesthetic Hypersensitivity Reactions in Pediatric Patients: A Retrospective Case-Control Study.

BackgroundLocal anesthetics (LA) are relatively safe and rarely cause immediate hypersensitivity reactions. The data on immediate LA hypersensitivity and its risk factors in children are limited.AimTo evaluate risk factors of immediate LA hypersensitivity.MethodsThe retrospective case-controlled study included 17 patients with confirmed immediate LA hypersensitivity. For each patient, three age- and gender-matched control subjects were included in the study. LA hypersensitivity was excluded by skin tests and subcutaneous drug provocation tests in all control subjects.ResultsThe most common allergic assessment in the patient/control group was for lidocaine (n=5; 29.4%, vs n=23; 45.1%). Suspected LA hypersensitivity reactions were found to be associated with cutaneous manifestations in 14 (82.4%) patients and in 7 (13.7%) of the controls. A history of exposure to local anesthetics twice or more was present in 11 (64.7%) patients vs 6 (11.8%) controls. In conditional regression analysis, repeated LA exposure (≥2) and cutaneous findings were determined as significant risk factors (Odds Ratio [OR]:5.7; 95% Confidence Interval [CI]:1.2–27.1; P=0.029 and (OR:17.3; 95% CI:3.6–82.5; P<0.001, respectively).ConclusionCutaneous manifestations and a history of LA exposure twice or more were predictive factors for LA allergy confirmed by skin test in children.

A Patient with Local Hypersensitivity Reactions to Three TNF-α Inhibitors and Local/Systemic Hypersensitivity Reactions to Tocilizumab: Desensitization to Tocilizumab

A Patient with Local Hypersensitivity Reactions to Three TNF-α Inhibitors and Local/Systemic Hypersensitivity Reactions to Tocilizumab: Desensitization to Tocilizumab

Langerhans dendritic cell vaccine bearing mRNA-encoded tumor antigens induces antimyeloma immunity after autotransplant

AbstractPosttransplant vaccination targeting residual disease is an immunotherapeutic strategy to improve antigen-specific immune responses and prolong disease-free survival after autologous stem cell transplantation (ASCT) for multiple myeloma (MM). We conducted a phase 1 vaccine trial to determine the safety, toxicity, and immunogenicity of autologous Langerhans-type dendritic cells (LCs) electroporated with CT7, MAGE-A3, and Wilms tumor 1 (WT1) messenger RNA (mRNA), after ASCT for MM. Ten patients received a priming immunization plus 2 boosters at 12, 30, and 90 days, respectively, after ASCT. Vaccines contained 9 × 106 mRNA-electroporated LCs. Ten additional patients did not receive LC vaccines but otherwise underwent identical ASCT and supportive care. At 3 months after ASCT, all patients started lenalidomide maintenance therapy. Vaccinated patients developed mild local delayed-type hypersensitivity reactions after booster vaccines, but no toxicities exceeded grade 1. At 1 and 3 months after vaccines, antigen-specific CD4 and CD8 T cells increased secretion of proinflammatory cytokines (interferon-γ, interleukin-2, and tumor necrosis factor-α) above prevaccine levels, and also upregulated the cytotoxicity marker CD107a. CD4 and CD8 T-cell repertoire analysis showed a trend for increased clonal expansion in the vaccine cohort, which was more pronounced in the CD4 compartment. Although not powered to assess clinical efficacy, treatment responses favored the vaccine arm. Triple antigen–bearing mRNA-electroporated autologous LC vaccination initiated at engraftment after ASCT, in conjunction with standard lenalidomide maintenance therapy for MM, is safe and induces antigen-specific immune reactivity. This trial was registered at www.clinicaltrials.gov as #NCT01995708.

“COVID arm:” Delayed local hypersensitivity reaction to ChAdOx1 nCoV-19 coronavirus vaccine

“COVID arm:” Delayed local hypersensitivity reaction to ChAdOx1 nCoV-19 coronavirus vaccine

Update on local anesthetics hypersensitivity reactions

Update on local anesthetics hypersensitivity reactions

Recent Advances in Allergen-Specific Immunotherapy in Humans: A Systematic Review.

Allergen-specific immunotherapy (AIT) is presumed to modulate the natural course of allergic disease by inducing immune tolerance. However, conventional AITs, such as subcutaneous immunotherapy and sublingual immunotherapy, require long treatment durations and often provoke local or systemic hypersensitivity reactions. Therefore, only <5% of allergy patients receive AIT as second-line therapy. Novel administration routes, such as intralymphatic, intradermal and epicutaneous immunotherapies, and synthetic recombinant allergen preparations have been evaluated to overcome these limitations. We will review the updated views of diverse AIT methods, and discuss the limitations and opportunities of the AITs for the treatment of allergic diseases in humans.

Pityriasis Rosea Shortly After mRNA-1273 COVID-19 Vaccination

With the increase in rates of vaccination against COVID-19, various cutaneous reactions have been reported after vaccination, including pityriasis rosea (PR) (Catala et al., 2021Catala A Munoz-Santos C Galvan-Casas C Roncero Riesco M Revilla Nebreda D Sola-Truyols A et al.Cutaneous reactions after SARS-COV-2 vaccination: A cross-sectional Spanish nationwide study of 405 cases.Br J Dermatol. 2021; Crossref PubMed Scopus (93) Google Scholar; Johansen et al., 2021Johansen M Chisolm SS Aspey LD Brahmbhatt M. Pityriasis rosea in otherwise asymptomatic confirmed COVID-19-positive patients: A report of 2 cases.JAAD Case Rep. 2021; 7: 93-94Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar; Marcantonio-Santa Cruz et al., 2021Marcantonio-Santa Cruz OY Vidal-Navarro A Pesque D Gimenez-Arnau AM Pujol RM Martin-Ezquerra G Pityriasis rosea developing after COVID-19 vaccination.J Eur Acad Dermatol Venereol. 2021; Crossref PubMed Scopus (13) Google Scholar; McMahon et al., 2021McMahon DE Amerson E Rosenbach M Lipoff JB Moustafa D Tyagi A et al.Cutaneous reactions reported after Moderna and Pfizer COVID-19 vaccination: A registry-based study of 414 cases.J Am Acad Dermatol. 2021; 85: 46-55Abstract Full Text Full Text PDF PubMed Scopus (436) Google Scholar). It is easy to overlook because the incidence of PR as a side effect of COVID-19 vaccination is extremely low, accounting for about 0.96% of all cutaneous reactions (McMahon et al., 2021McMahon DE Amerson E Rosenbach M Lipoff JB Moustafa D Tyagi A et al.Cutaneous reactions reported after Moderna and Pfizer COVID-19 vaccination: A registry-based study of 414 cases.J Am Acad Dermatol. 2021; 85: 46-55Abstract Full Text Full Text PDF PubMed Scopus (436) Google Scholar). A 29-year-old man presented with a herald patch on his right chest 2 hours after the second dose of mRNA-1273 COVID-19 vaccination (Figure 1A). Within 2–3 days, multiple skin lesions rapidly disseminated to the upper trunk and extremities (Figure 1B). He had no other systemic symptoms and no previous history of COVID-19 infection. Skin biopsy showed focal parakeratosis, spongiosis, and superficial perivascular inflammatory infiltrates (Figure 1C). Based on the clinical and histological features he was diagnosed with PR.Figure 1(A) A 3 × 4 cm sized, solitary large, erythematous patch with trailing scale (herald patch, white arrow) on his right chest. (B) Multiple oval, salmon-colored patches along the lines of cleavage on the trunk. (C) Histopathologic examination shows patchy parakeratosis, mild spongiosis, and perivascular lymphocytic infiltration. (Hematoxylin and Eosin, original magnification × 100).View Large Image Figure ViewerDownload Hi-res image Download (PPT) According to Ogata et al. (Ogata et al., 2021Ogata AF Cheng CA Desjardins M Senussi Y Sherman AC Powell M et al.Circulating SARS-CoV-2 Vaccine Antigen Detected in the Plasma of mRNA-1273 Vaccine Recipients.Clin Infect Dis. 2021; Crossref PubMed Scopus (55) Google Scholar), the SARS-CoV-2 viral spike protein antigen is detected as early as day 1 post-vaccination, and peak levels are detected after an average of 5 days. Based on the literature, the time lapse between COVID-19 vaccination and skin lesions ranges 5–17 days, with an average of 12.7 days. However, our patient developed PR after only 2 hours of receiving the vaccination, which is a very short time interval. This case did not enable a conclusion to be made that a true causal link exists between PR and vaccination. This is because the short interval of 2 hours may be insufficient for the vaccine to circulate throughout the bloodstream and induce an appropriate immune response. However, in this patient, the skin lesions occurred after the second dose of the vaccination, and it is possible that PR may occur sooner in such cases than after the first dose of the vaccination. Johnston et al. (Johnston et al., 2021Johnston MS Galan A Watsky KL Little AJ. Delayed Localized Hypersensitivity Reactions to the Moderna COVID-19 Vaccine: A Case Series.JAMA Dermatol. 2021; 157: 716-720Crossref PubMed Scopus (84) Google Scholar) recently reported that delayed localized cutaneous reactions may occur sooner after the second administration of the vaccine. Moreover, a previous history of PR is not generally related to recurrence or onset of the lesion, and is not an important consideration for this patient because there was no history of PR. Therefore, in the future, researchers should study the onset duration of cutaneous reactions that occur following the administration of the first and second doses of the COVID-19 vaccine. None. This study was performed in accordance with the Helsinki Declaration and the patient provided written informed consent for the publication of his case details. None. The authors have no conflicts of interest to declare.

ROLE OF LOCAL HEMOSTATIC AGENTS AS ADJUVANT IN CONTROL OF PRIMARY POSTPARTUM HEMORRHAGE

Background: Hemostasis is an integral and very important aspect of surgical practice. In the developing world, about 1.2% of deliveries are associated with PPH and when PPH occurred about 3% of women died. Causes of postpartum hemorrhage are uterine atony, trauma, retained placenta or placental abnormalities, and coagulopathy, commonly referred to as the four Ts. Objective: To study the effect of gelfoam in hemostasis as adjuvant in control of primary postpartum hemorrhage. Patients and Methods: This was a Cohort study conducted at Sayed Galal University Hospital, Al-Azhar University Faculty of Medicine during the period from May 2019 to May 2020. A number of 60 cases of postpartum hemorrhage and role of gel foam in hemostasis as adjuvant in control of primary postpartum hemorrhage. Results: The findings of the present study indicate that local hemostatic agent “gel foam” was useful as adjuvant in control of primary postpartum hemorrhage in cesarean section. Local hemostats reduce the use of systemic hemostats, shorten the time required to achieve hemostasis. The delay in the recovery of bowel motility was due to the local hypersensitivity reaction caused by gelatin sponge and/or dislocation of this local hemostat. Conclusion: Local hemostatic agent “gel foam” was useful in adjuvant in control of primary postpartum hemorrhage in cesarean section.

APPLICATION OF MULTIPOTENT MESENCHYMAL STEM CELL SECRETOME IN THE TREATMENT OF ADJUVANT ARTHRITIS AND CONTACT-ALLERGIC DERMATITIS IN ANIMAL MODELS

The therapeutic effect of multipotent mesenchymal stem cells has been proven on various disease models. One of the mechanisms is the paracrine effect of the cells on the surrounding tissues.The aim. To investigate the secretome effectiveness of the multipotent mesenchymal stem cells in the treatment of adjuvant arthritis and contact-allergic dermatitis in Wistar rats.Materials and methods.Adjuvant arthritis was simulated in 26 female rats by the administration of Freund's complete adjuvant and then treated with the administration of 100 µl of multipotent mesenchymal stem cell secretome or saline. Contact-allergic dermatitis was modeled on 30 female rats by applying 200 μl of an oil solution of dinitrofluorobenzene to the skin on days 1, 5 and 6. Then the rats were treated with fluocinolone ointment (a positive control), baby cream (a negative control), baby cream with a secretome of native multipotent mesenchymal stem cells or from the cells processed with dexamethasone.Results.Judging by the indicators of the longitudinal and transverse dimensions of the paws in rats and a histological examination, the secretome did not have any anti-inflammatory effect on adjuvant arthritis. A cream with a secret from multipotent mesenchymal stem cells processed with dexamethasone, was the most effective on the model of contact-allergic dermatitis: the clinical improvement occurred on the 2ndday. The secretome from native multipotent mesenchymal stem cells and fluocinolone had a therapeutic effect on the 3rdday of application, the negative control - on the 4thday. The lymphocytic infiltration coefficient was significantly lower (p &lt;0.05) in all the cases compared to the negative control (2.8 ± 0.1). However, the lowest infiltration was observed when the cream with secretome from native (1.75 ± 0,1) and dexamethasone-stimulated (1.76 ± 0.1) multipotent mesenchymal stem cells was being used.Conclusion.The cream with the secretome of multipotent mesenchymal stem cells suppresses lymphocytic infiltration more strongly than the highly active topical glucocorticosteroid - fluocinolone - on the model of contact-allergic dermatitis, which is a classic local delayed-type hypersensitivity reaction. However, a further study of the therapeutic effect of the secretome on models of systemic inflammatory diseases is required after its preliminary purification from large-molecular proteins.

Tick hypersensitivity and human tick-borne diseases.

Immune-mediated hypersensitivity reactions to ticks and other arthropods are well documented. Hypersensitivity to ixodid (hard bodied) ticks is especially important because they transmit infection to humans throughout the world and are responsible for most vector-borne diseases in the United States. The causative pathogens of these diseases are transmitted in tick saliva that is secreted into the host while taking a blood meal. Tick salivary proteins inhibit blood coagulation, block the local itch response and impair host anti-tick immune responses, which allows completion of the blood meal. Anti-tick host immune responses are heightened upon repeated tick exposure and have the potential to abrogate tick salivary protein function, interfere with the blood meal and prevent pathogen transmission. Although there have been relatively few tick bite hypersensitivity studies in humans compared with those in domestic animals and laboratory animal models, areas of human investigation have included local hypersensitivity reactions at the site of tick attachment and generalized hypersensitivity reactions. Progress in the development of anti-tick vaccines for humans has been slow due to the complexities of such vaccines but has recently accelerated. This approach holds great promise for future prevention of tick-borne diseases.

Intradermal test dose hypersensitivity reactions to antibiotics in a tertiary care hospital: A cross-sectional study

Background: Skin tests like the intradermal test (IDT) and skin prick test can be used for drug hypersensitivity prediction. An IDT is done by injecting intradermally an allergen or drug solution of volume 0.02–0.05 ml by raising a small bleb 3 mm in diameter. The injection site is read after 15–20 min for immediate reactions. The IDT is routinely done before administration of full-dose antibiotic in the majority of the hospitals. Aim and Objectives: The aims and objectives were to study the frequency of IDT dose hypersensitivity reactions to antibiotics and its outcome. Materials and Methods: 0.2 ml of the antibiotic was injected intradermally before full dose of the same. The test reading was done after 15–30 min after the injection and we looked for wheal, flare reaction, and itching. The drug causing the reaction, time of reaction, description of the reaction, the organ affected, and the outcome of the reaction were noted. Results: Two hundred and fifty-three patients were included in the study of which 32 patients had local hypersensitivity reactions to IDT dose. Redness and redness with induration were the most common reactions. The reaction to IDT dose of ciprofloxacin was the most commonly seen reaction in this study. Conclusion: The present study showed that the hypersensitivity reaction to IDT dose before the full dose of the antibiotic was fairly common and the IDT is possibly helpful in preventing allergic reactions to full dose.