Lymphocyte Transformation Test Research Articles

Identification of cross reactive T cell responses in adenovirus based COVID 19 vaccines

Vaccination has proven to be a valuable tool to combat SARS-CoV-2. However, reports of rare adverse reactions such as thrombosis/thrombocytopenia syndrome after ChAdOx1 nCoV-19 vaccination have caused scientific, public and media concern. ChAdOx1 was vectorised from the Y25 chimpanzee adenovirus, which was selected due to low human seroprevalence to circumvent pre-existing immunity. In this study, we aimed to explore patterns of T-cell activation after SARS-CoV-2 COVID-19 vaccine exposure in vitro using PBMCs collected from pre-pandemic ChAdOx1 nCoV-19 naïve healthy donors (HDs), and ChAdOx1 nCoV-19 and Pfizer vaccinated controls. PBMCs were assessed for T-cell proliferation using the lymphocyte transformation test (LTT) following exposure to SARS-CoV-2 COVID-19 vaccines. Cytokine analysis was performed via intracellular cytokine staining, ELISpot assay and LEGENDplex immunoassays. T-cell assays performed in pre-pandemic vaccine naïve HDs, revealed widespread lymphocyte stimulation after exposure to ChAdOx1 nCoV-19 (95%), ChAdOx-spike (90%) and the Ad26.COV2. S vaccine, but not on exposure to the BNT162b2 vaccine. ICS analysis demonstrated that CD4+ CD45RO+ memory T-cells are activated by ChAdOx1 nCoV-19 in vaccine naïve HDs. Cytometric immunoassays showed ChAdOx1 nCoV-19 exposure was associated with the release of proinflammatory and cytotoxic molecules, such as IFN-γ, IL-6, perforin, granzyme B and FasL. These studies demonstrate a ubiquitous T-cell response to ChAdOx1 nCoV-19 and Ad26.COV2. S in HDs recruited prior to the SARS-CoV-2 pandemic, with T-cell stimulation also identified in vaccinated controls. This may be due to underlying T-cell cross-reactivity with prevalent human adenoviruses and further study will be needed to identify T-cell epitopes involved.

First report of lymphocyte transformation test positivity in a delayed allergic reaction to ticagrelor

First report of lymphocyte transformation test positivity in a delayed allergic reaction to ticagrelor

A literature review and expert consensus statement on diagnostics in suspected metal implant allergy.

Although rare, allergic reactions to metal implants represent a diagnostic challenge in view of missing guidelines. To develop an European expert consensus on characteristics of metal allergy reactions and the utility of various diagnostic tools in suspected metal implant allergy. A nominal group technique (NGT) was applied to develop consensus statements. Initially an online literature database was created on a secure server to enable a comprehensive information. Twenty-three statements were formulated on potential aspects of metal implant allergy with a focus on diagnostics and grouped into five domains. For the consensus development, the panel of 12 experts initially did refine and reformulate those statements that were ambiguous or had unclear wording. By face-to-face (9/12) or virtual participation (3/12), an anonymous online voting was performed. Consensus (≥80% of agreement) was reached in 20/23 statements. The panel agreed that implant allergy despite being rare should be considered in case of persistent unexplained symptoms. It was, however, recommended to allow adequate time for resolution of symptoms associated with healing and integration of an implant. Obtaining questionnaire-aided standardized medical history and standardized scoring of patient outcomes was also considered an important step by all experts There was broad consensus regarding the utility/performance of patch testing with additional late reading. It was recognized that the lymphocyte transformation test (LTT) has to many limitations to be generally recommended. Prior to orthopaedic implant, allergy screening of patients without a history of potential allergy to implant components was not recommended. Using an expert consensus process, statements concerning allergy diagnostics in suspected metal implant allergy were created. Areas of nonconsensus were identified, stressing uncertainty among the experts around topics such as preoperative testing in assumed allergy, histological correlate of periimplant allergy and invitro testing, which underscores the need for further research.

In-vivo and ex-vivo tests for culprit drugs identification in severe cutaneous adverse drugs reactions.

Drug causality assessment in severe cutaneous adverse reactions (SCARs) remains challenging. We investigated the usefulness of in-vivo drug patch tests (PT), ex-vivo interferon (IFN)-γ enzyme-linked immunospot (ELISpot) assay, and lymphocyte transformation test (LTT) in 30 SCARs patients within the past 36 months. Drug PT yielded a 20% positivity rate (n = 6), while IFN-γ ELISpot and LTT showed positive rates of 56.67% (n = 17) and 41.38% (n = 12), respectively. Combining the three tests resulted in an overall positive rate of 66.67% (n = 20) of cases. IFN-γ ELISpot offered additional positivity, especially with oxypurinol. Employing a combined diagnostic approach may enhance the chances of obtaining a positive result.

Usefulness of the Lymphocyte Transformation Test in Allergy to Botulinum Toxin Type A.

Usefulness of the Lymphocyte Transformation Test in Allergy to Botulinum Toxin Type A.

Clinical Diagnostic Immunology in A Clinical Microbiology Laboratory

This review unravels the novel approaches, innovations and applications of immunology in the diagnosis of infections in a clinical microbiology laboratory. Many assays or tests in immunology are used in the diagnosis of infections. The availability of monoclonal antibodies has brought rapid progress to this area and they are used , for example , to identify specific microorganisms in culture or in tissues and fluids from infected patients. Examples of common diagnostic applications of antibody- antigen reactions discussed here includes agglutination tests, complement tests, complement fixation tests, ELISA, cytotoxic tests, radioimmunoassay tests, haemagglutination inhibition tests, hypersensitivity tests, phagocytic cell activity test, migration inhibition test, lymphocyte transformation test , lymphocyte fixation test , skin tests, delayed hypersensitivity tests and many others. The development of monoclonal antibody technology and the subsequent availability of unlimited quantities of pure antibody has improved the selectivity of these assays. The development of simple and highly sensitive methods for detection of nucleic acids is being applied to diagnosis of infection using nucleic acid hybridization and this provides a valuable additional aid to immunoassays in the clinical microbiology diagnostic laboratory.

Lymphocyte transformation tests predict delayed-type allergy to piperacillin/tazobactam in patients with cystic fibrosis

BackgroundAntibiotic treatment is crucial for patients with chronic bacterial infections. Suspected drug allergies often lead to inconsistent therapies and challenging clinical management for patients and caregivers. The objective of this study was to evaluate the value of lymphocyte transformation tests in comparison to skin tests for the prediction of delayed-type allergic reactions. MethodsThis prospective, observational study tested the diagnostic value of skin prick tests, intradermal tests (reading: 15 min and 72 h) and lymphocyte transformations tests for the prediction of allergic reactions in CF patients with physician reported allergy to piperacillin/tazobactam, meropenem and ceftazidime. The tests were performed directly before a 14d intravenous drug challenge. ResultsWe performed 33 drug challenges in 29 subjects. 21 drug challenges were negative (63 %); 12 lead to a reaction (37 %), of those 2 were immediate and 10 were delayed-type. 100 % of the skin prick tests were negative. 97 % (33/34) of the intradermal tests with early reading and 100 % of the intradermal tests with late reading yielded negative results. 5/11 patients who experienced a delayed-type reaction during the drug challenge had a positive lymphocyte transformations test. All 17 patients who did not react had a negative lymphocyte transformations test. For piperacillin/tazobactam, 4/5 patients who experienced a delayed-type reaction during the drug challenge had positive lymphocyte transformations tests. Hence, for piperacillin/tazobactam, the sensitivity of the lymphocyte transformation test for prediction of reactions was 80.0 % and the specificity 100 %. ConclusionWe demonstrate that the lymphocyte transformation test predicts delayed-type allergy to piperacillin/tazobactam in contrast to skin tests.

Establishing clinically meaningful ranges of metal hypersensitivity in orthopaedic patients using COVID-19 vaccine-induced adaptive immune responses from fully vaccinated adults

BackgroundThis study aimed to assess metal sensitization ranges among orthopaedic patients by comparing adaptive immune responses in all-comer pre- and post-operative orthopaedic adults who were COVID-19 unvaccinated or vaccinated vs patients with a painful aseptic implant by lymphocyte transformation test (LTT) to SARS-CoV-2-Spike-Protein (SP) and implant metal(s), respectively. MethodsData were retrospectively reviewed from three independent groups: unvaccinated COVID-19 adults (n = 23); fully COVID-19 vaccinated adults (n = 35); unvaccinated, painful aseptic implant patients with history of metal allergy (n = 98). Standard in vitro LTT for SP and implant metal(s) (nickel, cobalt) were performed and rated as negative (stimulation index [SI]<2), mild (SI ≥ 2), positive (SI ≥ 4–15), and high sensitization (SI > 15) adaptive immune responses to tested antigen. ResultsOverall, 17/23 (74%) of unvaccinated adults showed negative to mild LTT ranges, and 35/35 (100%) of vaccinated showed mild to positive LTT ranges to SP. Vaccinated individuals showed significantly higher median SI (16.1) to SP than unvaccinated (median SI, 1.7; P < 0.0001). Most vaccinated adults (94%) showed a lymphocyte SI > 4 to SP, establishing LTT SI ≥ 4 with >90% sensitivity for diagnosing effective COVID-19 adaptive immune responses. Significantly fewer painful orthopaedic patients (41%) showed comparable elevated levels of lymphocyte metal sensitivity at SI ≥ 4 compared to vaccinated group (P < 0.0001). ConclusionsVaccinated adults showed significantly higher lymphocyte SI to SP than unvaccinated indicating that SI ranges ≥4 should be set as unequivocally diagnostic of LTT-positive adaptive immune responses to tested antigen. This analysis supports using higher LTT SI ranges (SI ≥ 4) in diagnosing clinical orthopaedic-related Type IV metal-hypersensitivity responses among orthopaedic patients.

Are Allergy-Induced Implant Failures Actually Hypersensitivity Reactions to Titanium? A Literature Review.

This literature review was performed to assess whether implant failures are associated with titanium allergy. An electronic search of the MEDLINE/PubMed, Cochrane Library, and Scopus databases up to April 2021 was conducted, and the obtained articles were independently assessed by two reviewers. Articles describing cases of implant failure in which the cause of implant failure was only identified as allergy were included. Twelve studies were included. Eight studies identified Ti allergy by clinical examinations, of which four used patch tests, three used the lymphocyte transformation test (LTT)/memory lymphocyte immunostimulation assay (MELISA), and one used both tests. Nine studies reported cases of titanium hypersensitivity in combination with other systemic allergy-related disorders, with eight cases also showing positive results for Ni, Hg, Cr, and Co hypersensitivity. Ten papers reported the improvement of symptoms after the removal of the Ti implants and their replacement with zirconia implants, and two of these papers showed good results. Cases of probable titanium allergy included those with true titanium allergies and those with a potentially different cause. However, the differentiation of these cases is difficult. Since no definitive method has been established for diagnosing titanium allergy, a comprehensive diagnosis based on the clinical course and clinical examination using a patch test/LTT/MELISA is necessary. Implant treatment should be performed with caution in patients with any preoperative allergies.

Hypersensitivity to metals in metal-on-metal hip arthroplasty: a prospective study of one hundred and thirty five lymphocyte transformation tests

BackgroundMetal allergy remains a controversial topic in the orthopaedic community. It is not known if or to what degree metal sensitivity contributes to inflammatory soft tissue failures, unexplained residual pain, or clinical complications after total joint replacement with metal prostheses.MethodsWe investigated the efficacy of the lymphocyte transformation test (LTT) in predicting adverse outcomes in patients after receiving a metal joint replacement. Our study cohort consists of 135 metal-on-metal hip resurfacing arthroplasty cases performed between 2013 and 2015. All study patients had an LTT preoperatively. We retrospectively analyzed clinical outcomes and failures for our cohort.ResultsThere was no difference in LTT reactivity between men and women. Of the 135 patients tested, 46 (34.1% of cohort) tested positive to at least one of the materials comprising their implant, and 78 patients (57.8%) had at least one reactive score to any component of the LTT. After a minimum follow-up of two years, we did not observe an allergic response to the implant in any patients. There were no failures requiring revision. We observed a 2.2% rate of moderate residual pain; no patients with residual pain tested positive for metal sensitivity. When patients with moderate-high LTT reactivity (30.4% of cohort) were compared to the remainder of the study group, there was no difference in HHS or UCLA activity score. There was no correlation between blood metal ion levels and LTT reactivity.ConclusionWe were unable to prove any predictive value of the LTT. We failed to identify hypersensitivity to metals in patients with metal-on-metal hip resurfacing arthroplasty.

Lymphocyte transformation test in the diagnosis of adult fish-induced enterocolitis syndrome.

Lymphocyte transformation test in the diagnosis of adult fish-induced enterocolitis syndrome.

Patients with naproxen-induced liver injury display T-cell memory responses toward an oxidative (S)-O-desmethyl naproxen metabolite but not the acyl glucuronide.

Exposure to nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen (IBU) and naproxen (NAP) is associated with idiosyncratic drug-induced liver injury (DILI). Carboxylate bioactivation into reactive metabolites (e.g., acyl glucuronides, AG) and resulting T-cell activation is hypothesized as causal for this adverse event. However, conclusive evidence supporting this is lacking. In this work, we identify CD4+ and CD8+ T-cell hepatic infiltration in a biopsy from an IBU DILI patient. Lymphocyte transformation test and IFN-γ ELIspot, conducted on peripheral blood mononuclear cells (PBMCs) of patients with NAP-DILI, were used to explore drug-specific T-cell activation. T-cell clones (TCC) were generated and tested for drug specificity, phenotype/function, and pathways of T-cell activation. Cells were exposed to NAP, its oxidative metabolite 6-O-desmethyl NAP (DM-NAP), its AG or synthesized NAP-AG human-serum albumin adducts (NAP-AG adduct). CD4+ and CD8+ T-cells from patients expressing a range of different Vβ receptors were stimulated to proliferate and secrete IFN-γ and IL-22 when exposed to DM-NAP, but not NAP, NAP-AG or the NAP-AG adduct. Activation of the CD4+ TCC was HLA-DQ-restricted and dependent on antigen presenting cells (APC); most TCC were activated with DM-NAP-pulsed APC, while fixation of APC blocked the T-cell response. Cross-reactivity was not observed with structurally-related drugs. Our results confirm hepatic T-cell infiltrations in NSAID-induced DILI, and show a T-cell memory response toward DM-NAP indicating an immune-mediated basis for the adverse event. Whilst bioactivation at the carboxylate group is widely hypothesized to be pathogenic for NSAID associated DILI, we found no evidence of this with NAP.

Value of the Lymphocyte Transformation Test for the Diagnosis of Drug-Induced Hypersensitivity Reactions in Hospitalized Patients with Severe COVID-19.

In the first wave of COVID-19, up to 20% of patients had skin lesions with variable characteristics. There is no clear evidence of the involvement of the SARS-CoV-2 virus in all cases; some of these lesions may be secondary to drug hypersensitivity. To analyze the possible cause of the skin lesions, we performed a complete allergology study on 11 patients. One year after recovery from COVID-19, we performed a lymphocyte transformation test (LTT) and Th1/Th2 cytokine secretion assays for PBMCs. We included five nonallergic patients treated with the same drugs without lesions. Except for one patient who had an immediate reaction to azithromycin, all patients had a positive LTT result for at least one of the drugs tested (azithromycin, clavulanic acid, hydroxychloroquine, lopinavir, and ritonavir). None of the nonallergic patients had a positive LTT result. We found mixed Th1/Th2 cytokine secretion (IL-4, IL-5, IL-13, and IFN-γ) in patients with skin lesions corresponding to mixed drug hypersensitivity type IVa and IVb. In all cases, we identified a candidate drug as the culprit for skin lesions during SARS-CoV-2 infection, although only three patients had a positive drug challenge. Therefore, it would be reasonable to recommend avoiding the drug in question in all cases.

Overview of diagnostic laboratory tests and diagnostic criteria for liver injury caused by Kampo medicine

AbstractBackgroundSeveral studies have suggested that the known biomarkers and the diagnostic scales are unreliable for the diagnosis of Kampo‐induced liver injury (KMILI).Diagnostic BiomarkersThe lymphocyte transformation test (LTT) for Kampo medicines is likely to give false positive results, while the normal level of the basophil activation test (BAT) for diagnosing Kampo liver injury remains uncertain.Diagnostic ScaleDue to the lack of reliable biomarkers, diagnostic scales have been developed; however, the Digestive Disease Week [DDW])‐Japan criteria, which is widely used in Japan, has extremely low specificity for diagnosing KMILI.ConclusionThe diagnosis of KMILI remains challenging, and we eagerly await the development of reliable biomarkers for KMILI.

Liver injury related to Japanese herbal medicines: clinical features and diagnosis

The word “Kampo medicine” means the traditional Japanese herbal medicine. Even “natural herb” can cause drug-induced liver injury (DILI). In this review, the characteristics of Kampo medicine-induced liver injury (KMILI) are reported. The main causative herb involved in Kampo medicine is Scutellariae Radix. KMILI is based on certain hypersensitivity reactions. A small amount of Kampo medicine can cause liver injury, and KMILI can develop after a short latency period. The incidence of liver injury related to Scutellariae Radix is about 1%. KMILI is usually mild and not fatal. The latency period usually lasts 4 weeks to 24 weeks. Fatigue and loss of appetite are sometimes observed. Eosinophilia is not frequently observed. All three types of liver injuries are observed in KMILI: cholestatic, hepatocellular, and mixed types. In Japan, lymphocyte transformation test (LTT) has been generally used for the diagnosis of DILI; however, LTT is likely to yield false-positive result for Kampo medicines, and thus often leads to misdiagnosis in many cases. Recently, researchers reported that a specific human leukocyte antigen (HLA) genotype is possibly associated with KMILI. This hypothesis needs to be examined further. Although Kampo medicine is based on rich knowledge and experience that occurred over a period of thousands of years, much is still unknown about KMILI.

IFN-γ secretion of PBMC from non-drug-allergic control persons: Considerations for the validity of a positive lymphocyte transformation test

BackgroundThe lymphocyte transformation test (LTT) is used for the in vitro detection of a drug sensitization in assumed drug allergic patients. It is based on the detection of antigen (drug)-specific activation of T cells indicated by e.g. proliferation or cytokine secretion.However, occasional stimulatory effects of the drug unrelated to specific drug-allergic mechanisms can only be detected if a larger number of non-drug allergic control persons are tested with this specific drug. In this respect, the overall specificity of the LTT with ELISA read-out is summarized in several review articles, but the impact of a specific drug on the specificity has not yet been analyzed in a larger set of control persons. ObjectiveDo amoxicillin, cefuroxime and clindamycin induce an interferon (IFN)-y or interleukin (IL)-5 secretion of PBMC from control persons using the LTT with ELISA read-out? MethodsWe performed LTTs with amoxicillin, cefuroxime and clindamycin and determined drug-specific IFN-γ and IL-5 secretion measured by ELISA read-out. We included PBMC from 60 non-drug allergic control persons, who were unexposed to the tested drug at the time of blood donation. ResultsPBMC from 12 out of 23 control persons tested with amoxicillin gave a positive stimulation index (SI > 3.0) for IFN-γ resulting in a specificity of 47.8%. The corresponding specificity was 75% for cefuroxime (5/20 if SI > 3.0) and 58.8% for clindamycin (7/17, if SI > 2.0), respectively. In a next step, we calculated the Δ IFN-γ concentration by subtracting the background IFN-γ concentration in the unstimulated sample from the stimulated sample. After stimulation with amoxicillin, a mean concentration of 21.0 pg/mL IFN-γ was secreted. The less outlier prone median concentration was 7.4 pg/mL and much higher than for cefuroxime (1.7 pg/mL) and clindamycin (1.0 pg/mL).Remarkably, IL-5 concentrations were below the detection limit (< 1 pg/mL) for all drugs in all control persons who responded to TT. ConclusionConsideration of these observations may be helpful since a positive LTT result in a control patient may challenge the validity of a positive LTT result in the same experiment for a patient with assumed drug allergy.

#5781 DRUG-INDUCED ACUTE INTERSTITIAL NEPHRITIS (D-AIN): HOW TO IDENTIFY THE RESPONSIBLE DRUG?

Abstract Background and Aims The mainstay of D-AIN treatment is the removal of the responsible drug. However, it is not always easy to identify the culprit drug as this entity mainly affects elderly patients on multiple medications, they rarely associate systemic symptoms (rash, fever), and the timeline regarding the diagnosis and the associated drug is not always clear. Therefore, the diagnosis and treatment are delayed, making full renal function recovery less likely. The lymphocyte transformation test (LTT) has demonstrated to be useful in the identification of the involved drug in other hypersensitivity-mediated lymphocyte T diseases such as Stevens-Johnson Syndrome or Dress Syndrome. For this reason, we wonder if this test could be relevant in identifying the responsible drug in D-AIN. The aim of this study is to test LTT in patients with clinical and histological diagnosis of D-AIN. Method We have conducted a retrospective observational study in which we have collected data from 2019 to 2022 from our electronic databases. Results: We have registered 9 cases of D-AIN diagnosed with histological confirmation in whom the LTT had been performed. 22.2% of these patients were men. The mean age was 48.1 years (standard deviation of 15.8). None of them had previous chronic kidney disease (CKD). Mean peak creatinine at diagnosis was 4.66 mg/dl (standard deviation of 1.95). Regarding the typical symptoms of the D-AIN, three patients (33%) presented with fever and none of them suffered from rash. 6 patients had sterile pyuria (66%). All of them received steroid treatment. Concerning the LTT results, 7 cases were positive for one of the drugs the patient was taking, and 2 were negative. Among the positive cases, the identified drugs were 1 case of beta lactams (piperacillin), 1 case of PPIs (omeprazole), 1 case of metamizole, 1 case of paracetamol, 1 case of eslicarbazepine and 2 cases of NSAIDs (dexketoprofen), while the negative cases have not been suspected of taking any culprit drug. Conclusion LTT may be a useful test to identify the responsible drug for D-AIN, especially in patients taking multiple medications in which may be included some of great importance like immunotherapy (typical cause of D-AIN) in oncological treatments. In negative cases, it could be expected that the patient had taken medications difficult to be identified in the clinical history or, in some situations, the drug hapten responsible for kidney damage might be a drug metabolite and not the drug itself, which cannot be detected by the test.

A case of Familial Mediterranean Fever presented with recurrent infection.

The periodic fever syndrome Familial Mediterranean Fever (FMF) is caused by mutations in MEFV, which promote inflammation and present with uncontrolled systemic and organ-specific inflammation that can resemble infectious conditions. It is diagnosed based on clinical criteria, including frequent symptoms such as abdominal and thoracic pain, family history, and response to treatment with colchicine, which is confirmed by genetic assessment. Herein, we present a case of FMF with a relatively uncommon presentation. A 22-month-old female was referred to the allergy and clinical immunology clinic with eczematoid skin rashes. She was admitted to the hospital several times since the 2nd day of life with different complaints like fever, seizure, and restlessness, and treated with the diagnosis of septicemia. Endoscopy and colonoscopy were done at the age of 6 months due to poor weight gain and bloody diarrhea, which revealed active crypt-destructive colitis with foci of erosion in favor of infectious or allergic colitis. The colon biopsy was negative for Cytomegalovirus (CMV). Regarding family history, she was the second child of the first cousins parents and had a healthy 12-year-old sister. There was a history of death for unknown reasons of her cousin, whose parents were related. The immunologic evaluation was done, which showed a relatively normal immunoglobulin level, antibody response, flow cytometry, and lymphocyte transformation test. Nonetheless, a genetic study was done, which showed a homozygote mutation in exon 10 of the MEFV gene in the patient and a heterozygote mutation in both her parents. The periodic fever syndrome Familial Mediterranean Fever (FMF) is caused by mutations in MEFV, which promote inflammation and present with uncontrolled systemic and organ-specific inflammation that can resemble infectious conditions. The patient was diagnosed with FMF, and treatment was started using colchicine, which successfully controlled the patient's symptoms and prevented the recurrence of fever and other inflammatory manifestations.

Severe Cutaneous Adverse Drug Reactions at a Tertiary Care Center in Saudi Arabia.

Severe cutaneous adverse drug reactions (SCARs), although rare, are known to be associated with significant morbidity and mortality. SCARs include drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN), and acute generalized exanthematous pustulosis (AGEP). Studies on SCARs are limited in Saudi Arabia. This study aims to characterize SCARs at a tertiary care center in Saudi Arabia. A cross-sectional study was conducted at King Abdulaziz Medical City, Riyadh, Saudi Arabia. All inpatient and emergency department consultations to dermatology were electronically reviewed during the period from January 2016 to December 2020. All patients who developed an adverse cutaneous drug reaction were enrolled. Detailed analysis was performed only for SCARs. The culprit medication was determined based on the latency period, history of previous intake of the medication, and drug notoriety. There were 3050 hospital consultations to dermatology during the study period. Cutaneous adverse drug reactions constituted 253 (8.3%) cases. A total of 41 patients with SCARs were identified, accounting for 16.2% of all cutaneous drug reactions. Antibiotics and anticonvulsants were the most common causative drug groups accounting for 28 (68.3%) and 9 (22%) cases, respectively. DRESS was the most common SCAR. The latency period was the longest for DRESS and shortest for AGEP. Vancomycin was responsible for approximately a third of DRESS cases. Piperacillin/tazobactam was the most common cause for SJS/TEN and AGEP. The majority of drugs causing AGEP were antibiotics. The mortality rate was the highest in SJS/TEN (5/11 (45.5%)), followed by DRESS (1/23 (4.4%)) and AGEP (1/7 (14.3%)). SCARs are rare in Saudis. DRESS appears to be the most common SCAR in our region. Vancomycin is responsible for most cases of DRESS. SJS/TEN had the highest mortality rate. More studies are required to further characterize SCARs in Saudi Arabia and Arabian Gulf countries. More importantly, thorough studies of HLA associations and lymphocyte transformation tests among Arabs with SCARs are likely to further improve patient care in the Arabian Gulf region.

Gyógyszerallergiák tesztelése az SZTE Bőrgyógyászati és Allergológiai Klinika allergológiai osztályán

The authors present protocols of the options, available panels in drug allergy testing applied at the Department of Dermatology and Allergy, University of Szeged. In suspicion of drug induced hypersensitivity reaction we recommend performing lymphocyte transformation test (LTT), prick testing, intradermal testing and patch testing according to the assumed immune -mechanism. If these examinations are negative, the next step is the drug provocation test, which is the gold standard in the diagnosis of drug allergy. We summarize methods, indications, and the evaluation of each tests. There are increasing patients presenting hypersensitivity reactions who require proper identification of the culprit drug.