Israel Medical Association Journal

Background: Determining the accuracy of interferon gamma-releasing assays (IGRAs) is difficult due to the lack of a gold standard test for diagnosing latent tuberculosis (LTB). 

Objectives: To analyze the guidelines used for interpreting IGRAs in determining prophylactic treatment management for latent tuberculosis (LTB) in Israel.

Methods: We analyzed the retrospective data of 367 subjects who were referred to our laboratory during the period 2007–2011 for QuantiFERON Test-Gold In Tube (QFT-GIT) tests because of suspected LTB. Demographics and clinical data were retrieved from a questionnaire at enrollment, and 166/367 (45%) were further interviewed by phone in order to complete follow-up information on prophylactic TB treatment. 

Results: The majority of subjects (116/166, 69.9%, P < 0.0001) were spared prophylactic treatment subsequent to QFT-GIT testing. Subjects with negative QFT-GIT and positive tuberculin skin test (TST) results who were BCG-vaccinated had the lowest treatment rates (6/68, 8.8%, P < 0.0001). Most BCG-vaccinated subjects with positive TST and negative QFT-GIT test results received treatment with anti-tumor necrosis factor-alpha (TNFα) (17/19, 89.5%, P = 0.004). We found more negative QFT-GIT test results in subjects who were receiving anti-TNFα or steroid and other immunosuppressive treatment prior to testing (11/11, 100%, P = 0.029; 22/26, 84.6%, P = 0.06; 15/17, 88%, P = 0.06, respectively). 

Conclusions: Deciding on LTB prophylactic treatment in Israel is highly influenced by QFT-GIT test results. QFT-GIT findings contribute to clinical decisions, but their interpretation must also consider the patient’s medical history and clinical characteristics. 

 

Background: Dyspnea may be a presenting symptom of type I food hypersensitivity, and bronchial hyper-reactivity, without known asthma, can coexist in patients with food allergy.

Objective: To evaluate airway involvement in young adult patients with food allergy and no asthma and compare the findings to those of patients with food allergy and asthma, with food allergy and allergic rhinitis, with asthma and no food allergy, and of apparently healthy controls.

Methods: The evaluation involved prick skin test to food (65 allergens) and inhalants (24 allergens), spirometry, methacholine inhalation challenge, and induced sputum for cell analysis. The five groups consisted of 18 patients with food allergy alone, 11 with food allergy and asthma, 13 with food allergy and allergic rhinitis, 10 with asthma alone, and 10 controls.

Results: Patients with food allergy alone were mainly (86%) skin sensitive to pollens. Those with either asthma or allergic rhinitis were mainly (95%) sensitive to mites. BHR was detected in 40% of the patients with food allergy alone, 55% of the patients with allergic rhinitis, and 100% of the patients with asthma. Cell counts in the sputum of patients with asthma and in those with food allergy and asthma showed higher eosinophil counts compared to those with food allergy and allergic rhinitis. Patients with food allergy and no asthma, regardless of BHR status, had mainly neutrophils in the sputum.

Conclusions: Patients with food allergy are highly likely to have concomitant asymptomatic BHR. Mite sensitivity in patients with food allergy predicts respiratory allergy (either asthma or allergic rhinitis). High eosinophil levels in the sputum of food allergy patients predict respiratory involvement.

Background: The anti-inflammatory effect of montelukast, a leukotriene receptor antagonist, in patients with bronchial asthma is not entirely clear. Basophils can release a variety of mediators, including histamine and leukotriens, which most likely play an active part in the late allergic response.

Objectives: To study the effect of montelukast (10 mg/day) on histamine and cysteinyl leukotriene release from basophils taken from 12 mild atopic asthmatic patients who were given the drug for 4 weeks.

Methods: Basophils were withdrawn at baseline, and after 48 hours, 1 week, and 4 weeks of therapy. Histamine was measured by a radioenzymatic method and leukotrienes by immunologic assay. Histamine and cysLT release was measured spontaneously and following stimulation with interleukin-3 and anti-immunoglobulin E. Spirometry and symptom score were measured before and during treatment.

Results: During the treatment with montelukast there were no significant changes in spontaneous, IL-3 and anti-IgE‑induced histamine release. cysLT release decreased significantly only after 4 weeks of treatment (from 2899 ± 550 pg/ml at baseline to 2225 ± 430 pg/ml at 4 weeks, P = 0.02).

Conclusions: Montelukast does not seem to affect the release of histamine from basophils but mildly inhibits the cysLT release seen after 4 weeks of treatment.

The induced sputum technique allows sampling of the airways in a non-invasive manner and thus offers a unique opportunity to identify biomarkers of potential clinical utility in respiratory medicine. Sputum cells were originally examined in stained smears and the procedure was applied in both research and clinical settings from the 1950s through the 1970s. The cells, recovered from spontaneous coughing, were used to study lung cancer and respiratory infections and, later on, to diagnose Pneumocystis carinii pneumonia in patients infected with human immunodeficiency virus. The method was largely improved by the induction of sputum with aerosol of hypertonic saline and was extended to become part of the assessment of airway inflammation in bronchial asthma and chronic obstructive pulmonary disease. It was recently shown that induced sputum can be used to study interstitial lung diseases and, more specifically, sarcoidosis, non-granulomatous ILD[1], occupational lung diseases and other systemic diseases with lung involvement.

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Objective: To examine to what extent and for how long nedocromil sodium prevents exercise-induced asthma when given immediately before exertion compared to chronic administration.

Patients and Methods: Eighteen asthmatic patients were given 4 mg NS at 30 min or 3.5 hours before exertion. We compared the resultant effect with that of the same protocol measured after 2 and 4 weeks of continuous treatment with the drug.

Results: Nedocromil sodium decreased exercise-induced asthma similarly at both points when given acutely. Chronic treatment of up to 4 weeks did not improve this protective effect at either interval following the inhalation.

Conclusion: Nedocromil sodium most likely reaches its maximal effect on exercise-induced asthma upon the first administration, although treatment for longer than 4 weeks might be required to prove a chronic effect of the drug.