This study consists of the largest series of patients with drug-sensitive tuberculosis who developed type 1 IgE-mediated drug hypersensitivity while receiving treatment.
In addition to studies reporting that type 1, IgE-mediated hypersensitivity due to antituberculosis treatment is associated with female gender (4, 13, 14); There are also studies stating that hypersensitivity reactions are not affected by gender. (15) In our study, there was no difference between male and female genders.
The most common skin finding was urticaria; In the literature, the most common skin finding in type 1 IgE-mediated hypersensitivity is stated as urticaria. (16, 17)
Our hospital is one of the major centers for tuberculosis in Turkey and is located in Turkey's largest metropolis, such as Istanbul. All of our patients are citizens of the Republic of Turkey; He was of Asian descent by nationality. Looking at the literature, female gender, Asian origin, advanced age and HIV infection are associated with adverse reactions in antituberculosis treatment. (18) We think that this predisposition in those of Asian descent may be related to genetic predisposition, HLA.
In the patient who develops hypersensitivity, all drugs are stopped and the current situation is treated, and then giving the drugs one by one by desensitization is the approach we recommend. The most common agent found to be responsible for hypersensitivity was pyrazinamide in our study. In this case, we think that the last addition to desensitization would be more appropriate.
Considering 9 patients who underwent diagnostic testing, the prick test was positive in isoniazid in one patient. This patient was able to tolerate isoniazid with desensitization without any problems. In the same patient, urticaria developed when rifampicin was first added to the treatment with desensitization, but all drugs could be started again with desensitization for the second time. In yet another patient, the prick test and intradermal test performed with drugs were found to be negative; When drugs were started with desensitization, urticaria developed with isoniazid in the first desensitization, and urticaria with ethambutol developed in the second desensitization, and isoniazid-ethambutol was removed from the regimen and an alternative regimen was started. In this case, it is seen that there is a need for validation in diagnostic tests performed with antituberculosis drugs. Data on basophil activation test used in Type1 IgE-mediated reactions are limited. Despite limited data with lymphocyte transformation test, it can talk about low sensitivity and high specificity. (19) However, the use of these tests is also limited due to their cost.
The gold standard for finding the drug responsible for drug hypersensitivity is drug provocation. Even if diagnostic skin tests cannot be performed, when the drugs are re-administered, finding the responsible agent and removing it from the treatment is compatible with better treatment results. (20) Restarting the treatment with desensitization, not removing strong drugs such as isoniazid and rifampicin from the regimen provides a shorter treatment time and treatment success (1, 2) The duration of treatment with secondary antituberculosis drugs without first generation agents can be up to a minimum of 18 months. (21) It is a more effective method to give the primary drugs by desensitization instead of immediately replacing them with secondary drugs. (22) We also recommend that primary antituberculosis drugs be administered by desensitization and, if unsuccessful, regimen changes are made.
In tuberculosis, while it is necessary to stop the drugs due to the developing hypersensitivity reaction, it is necessary to start the maintenance treatment quickly due to the risk of drug resistance and reactivation. (23) Bermingham et al. suggested that in type 1 IgE-mediated reactions, while the drugs will be restarted, several different pathways can be followed. One of them is that all drugs can be given with rapid drug desensitization and this decision should be made for the patient. (24) We also recommend performing diagnostic tests, if possible, and administering all drugs by desensitization, leaving the positive agent for the last. If a diagnostic test cannot be performed, we think that it is appropriate to administer the drugs isoniazid, rifampicin, ethambutol and pyrazinamide, respectively. Because adverse drug reactions related to antituberculosis treatment can cause treatment failure, morbidity and mortality. This situation leads to increased economic results with more frequent hospital admissions, hospitalizations and more examinations. (25) We believe that the right management will bring success.
When we look at the treatment results, 84% of the patients successfully completed the treatment after desensitization. No treatment failure was observed. Although there are different schemes recommended for desensitization (26, 27, 28, 29), we can say that our scheme is usable when we look at our treatment results.
In conclusion, our study is the largest series of patients in which the demographic and clinical characteristics of type 1 IgE-mediated hypersensitivity developed under antituberculosis treatment were examined. An applicable, understandable and successful diagnostic process roadmap and desensitization scheme that can be used in this situation are presented.