Rare immediate hypersensitivity to rifampicin in a patient with tuberculosis requiring drug discontinuation.

A 47-year-old Turkish female patient was diagnosed with tuberculosis of the sacro-iliac joints and terminal ileum. She developed a severe adverse drug reaction while taking first-line tuberculosis therapy consisting of isoniazid, pyrazinamide and rifampicin as Rifater and ethambutol. Within 5 min of ingestion she developed pruritic rash, angioedema and breathing difficulties, resulting in an A&E admission. The tuberculosis therapy was discontinued. Intradermal and oral challenge tests for rifampicin were conducted but abandoned early on due to reactions which included audible wheeze, vomiting, throat pain and violent rigours. Clinical manifestations were swiftly treated with appropriate medications. This resulted in a change to the tuberculosis treatment regime, where streptomycin, isoniazid, ethambutol and pyrazinamide were given for 2 months and isoniazid and ethambutol for 12 months. Allergic reactions to rifampicin are rare and should be distinguished from flushing due to pyrazinamide. Prompt diagnosis and treatment by clinicians can be life saving.

Early improvement of patients' condition during allergen-specific subcutaneous immunotherapy with a high-dose hypoallergenic 6-grass pollen preparation.

OBJECTIVE: A double-blind, placebo-controlled study was performed with 37 patients to assess the efficacy as well as the safety of short-term pre-seasonal subcutaneous immunotherapy (SCIT) with a six-grass pollen allergoid for one year. RESULTS: After one pre-seasonal treatment cycle there are significant differences between the groups in favour of active treatment. On a "1-10" visual rating scale patients' condition is improved in the active group by a median of 2.5 points, whereas no change is found in the placebo treated group (p = 0.024). Thirteen of 20 (65%) actively treated patients in comparison to 6 of 17 (35%) placebo treated patients improved for at least two points which was defined as clinically relevant. The efficacy of SCIT is further demonstrated by significantly reduced skin test reactivity and significant increases in immunological parameters like allergen-specific IgG1 and IgG4 in actively treated patients. Injections are well tolerated and only mild to moderate systemic reactions occurred. CONCLUSION: The high-dose hypoallergenic grass pollen preparation was shown to be safe and clinically efficacious. One pre-seasonal course of 7 SCIT injections was sufficient to reach significant and clinically relevant efficacy with good safety.

Additional benefit of a third year of specific grass pollen allergoid immunotherapy in patients with seasonal allergic rhinitis.

BACKGROUND: Aluminium-adsorbed six grass pollen allergoid therapy for 2 years was found to be efficacious and safe in patients with hay fever and seasonal asthma. Using high-dose, hypoallergenic allergen products (allergoids) enables a short-term pre-seasonal treatment regimen. However, it is not known whether further treatment beyond 2 yrs had any additional benefit. METHODS: Following an initial 2-year randomized, double-blind, multi-centre, placebo-controlled clinical trial in 154 grass pollen-allergic patients, an additional short course of specific immunotherapy with the high-dose, hypoallergenic grass pollen preparation Allergovit was performed in 61 patients of the active treatment group during the 3rd open-label treatment year. RESULTS: Further treatment of patients with the Allergovit 6-grass pollen preparation resulted in a further reduction of symptom medication score and improved quality of life in comparison to the first and second treatment year. Changes in allergen-specific IgG4 levels supported these results. CONCLUSIONS: Pre-seasonal short-term immunotherapy with the high-dose, hypoallergenic allergen preparation Allergovit has been shown to be efficacious and safe. A course of three years of 6-grass pollen SIT further improves allergic symptoms, quality of life and reduces the need for anti-allergic medication.

Mechanisms of immunotherapy in allergic rhinitis.

Allergic rhinitis is a common condition, but many people still experience suboptimal control of symptoms despite measures such as allergen avoidance, intra-nasal steroids and antihistamines. Specific immunotherapy (SIT) has been used for many years, but though many studies show clinical efficacy, its mechanism of action is still not clearly understood. Earlier studies showed changes in antibodies and it may be that SIT works through mechanisms that alter the ratio of 'protective' IgG4 to 'pro-allergenic' IgE. Other studies have shown a reduction in eosinophil migration to nasal mucosa as well as a reduction in inflammatory mediator release including basophil histamine release. More recent studies have proposed that SIT works through inhibition of T-helper 2 lymphocytes (Th2) which preferentially produce cytokines that promote allergic responses. SIT may cause a deviation from Th2 to Th1 (T-helper 1 lymphocytes) or may induce T-regulatory cells (T-regs) which inhibit Th2 responses directly or through inhibitory cytokines.

Cytokine expression during allergen-induced late nasal responses: IL-4 and IL-5 mRNA is expressed early (at 6 h) predominantly by eosinophils.

The production of TH2-type cytokines [interleukin-4 (IL-4) and IL-5] and tissue eosinophilia are characteristic features of allergic diseases. It was previously reported that at 24 h after allergen provocation, CD3+ T-lymphocytes were the principal cell source of IL-4 and IL-5 mRNA transcripts in both atopic asthma and rhinitis. To investigate whether IL-4 and IL-5 mRNA are expressed earlier during late nasal responses and if so, which cell(s) are responsible. Nasal biopsies were obtained at 6 h after nasal allergen challenge and following a control challenge with the allergen diluent. Sections were immunostained for T-lymphocytes (CD3+, CD4+) and eosinophils (EG2+). In situ hybridization was used to detect the number of cells expressing messenger RNA (mRNA) for IL-4 and IL-5. In patients with allergic rhinitis, eosinophils (EG2+ cells P = 0. 006) but not T- cells (CD3+ cells) increased in the nasal mucosa at 6 h after allergen challenge. The number of cells expressing IL-4 mRNA (P = 0.01) and IL-5 mRNA (P = 0.05) also increased at 6 h. Co-localization studies showed that 76% of IL-4 mRNA+ cells and 77% of IL-5 mRNA+ cells were eosinophils, whereas at this time point, T-cells and mast cells accounted for

Allergen-induced proliferation and interleukin-5 production by bronchoalveolar lavage and blood T cells after segmental allergen challenge.

In order to detect and characterize allergen-specific T cells in the airways of atopic asthmatics, we measured proliferation and cytokine production by bronchoalveolar lavage (BAL) T cells isolated from Dermatophagoides pteronyssinus (Der p)-sensitive asthmatics and nonatopic control subjects, and compared the results with those generated using peripheral blood (PB) T cells. BAL and PB mononuclear cells were collected 24 h after segmental allergen challenge by fibreoptic bronchoscopy and venepuncture, respectively. T cells purified from BAL and PB were stimulated with autologous, irradiated antigen-presenting cells and D. pteronyssinus extract or a control, nonallergen antigen (M. tuberculosis purified protein derivative [PPD]). IL-5 and IFN-gamma concentrations were measured in culture supernatants by ELISA, and T-cell proliferation by 3H-thymidine uptake. D. pteronyssinus-induced proliferation of T cells derived from both BAL and PB was elevated in asthmatics when compared with control subjects (p < 0.05), whereas PPD-induced proliferation was equivalent in both compartments. In the asthmatics, D. pteronyssinus-induced proliferative responses of equivalent numbers of BAL and PB T cells obtained after allergen challenge were statistically equivalent. Nevertheless, BAL T cells stimulated with D. pteronyssinus produced significantly greater amounts of IL-5 than did PB T cells (p < 0.05). Allergen-induced proliferation and IL-5 production by BAL T cells in the asthmatics after segmental allergen challenge correlated with the percentages of eosinophils in the BAL fluid (p < 0.01). Further, BAL T cells from asthmatic patients produced significantly higher amounts of IL-5 than did the same number of cells from nonatopic control subjects (p < 0.05). We conclude that, in D. pteronyssinus-sensitive asthmatics, allergen-specific T cells can be detected in the bronchial lumen after allergen challenge and that allergen-induced proliferation and IL-5 production by these cells correlates with local eosinophil influx. Although bronchial luminal T cells show an equivalent proliferative response to allergen stimulation as compared with PB T cells, they do produce more IL-5, consistent with the hypothesis that local differentiation or priming of these cells within the bronchial mucosal environment results in upregulation of allergen-induced IL-5 secretion.

Increased expression of high affinity IgE (FcepsilonRI) receptor-alpha chain mRNA and protein-bearing eosinophils in human allergen-induced atopic asthma.

FcepsilonRI receptors play an important role in allergen-induced mediator release and antigen presentation by mast cells, basophils, and monocyte/macrophages in atopic disorders. The expression of FcepsilonRI by tissue eosinophils in atopic asthma after allergen challenge has not been established. For this reason we attempted to identify mRNA and protein product + FcepsilonRIalpha eosinophils in cytospins made from bronchoalveolar lavage (BAL) from atopic asthmatics (n = 9) and nonatopic normal subjects (n = 4) 24 h after segmental challenge with allergen or diluent. Messenger RNA for FcepsilonRIalpha was determined using in situ hybridization and FcepsilonRIalpha protein expression by immunocytochemistry using a mouse monoclonal antibody 22E7. Colocalization of FcepsilonRIalpha receptors to eosinophils was performed using chromotrope 2R. When compared with a control challenge, segmental challenge with Dermatophagoides pteronyssinus induced significant BAL eosinophilia (p = 0.007). The total number of BAL FcepsilonRIalpha mRNA and protein-positive cells also increased in asthmatics, median values 2 (0.7-7.2) and 11.5 (0.6-65.0) x 10(6) cells (p = 0.02) and 0 (0-0.3 x 10(6)) and 3.1 x 10(6) (0.45 - 162.5 x 10(6)) cells (p = 0.007), respectively, for mRNA and protein. Net increases in FcepsilonRIalpha+ cells correlated with the net increases in BAL eosinophils (r = 0.98, p = 0.0001 for mRNA and r = 0.72, p = 0.02 for protein). Colocalization studies with chromotrope 2R revealed that only 4% of FcepsilonRIalpha+ cells were eosinophils after control challenge and, in contrast, 85 to 95% of FcepsilonRIalpha+ cells were eosinophils after allergen. There were no differences in the numbers of FcepsilonRIalpha+ cells or eosinophils in normal control subjects. Our results demonstrated that local endobronchial allergen provocation in atopic asthmatics results in increased synthesis and expression of FcepsilonRIalpha predominantly on BAL eosinophils.

IL-4- and IL-5-positive T lymphocytes, eosinophils, and mast cells in allergen-induced late-phase cutaneous reactions in atopic subjects.

It has previously been shown that cells mRNA+ for T(H2)-type cytokines (IL-4 and IL-5) infiltrate the site of allergen-induced cutaneous late-phase reactions (LPR) in atopic subjects. In this study we have used the same experimental model to identify the cell source of both IL-4 and IL-5 mRNA and protein product. Allergen-induced LPRs were provoked in the skin of atopic individuals and the sites microscopically examined at 6, 24, and 48 hours. Using single in situ hybridization and immunohistochemistry, we first showed that the numbers of IL-4 and IL-5 mRNA and protein product positive cells peaked at 24 hours. This coincided with the magnitude of the LPR. By double in situ hybridization/immunohistochemistry, we then established (in 24-hour biopsy specimens) that the percentage of CD3+ T lymphocytes, EG2+ eosinophils, and tryptase-positive mast cells that were either IL-4 or IL-5 mRNA+ was 19%, 24%, and 5% and 19%, 20%, and 5%, respectively. Conversely, the percentage of EG2+ and tryptase-positive cells that were IL-4 or IL-5 protein product positive were 62% and 53% and 72% and 29%, respectively. IL-4 and IL-5 protein did not colocalize to CD3+ cells. CD68+ macrophages were negative in both in situ hybridization and immunohistochemistry. With eosinophils we obtained direct evidence of time-dependent stimulus-induced IL-4 and IL-5 mRNA transcription by semiquantitative reverse transcription-polymerase chain reaction of cells incubated with either IgG- or sIgA-coated particles in vitro. Taken together, these experiments suggest that eosinophils, mast cells, and T cells all contribute in variable degrees to the expression of IL-4 and IL-5 in human cutaneous LPR. The failure to colocalize IL-4/IL-5 protein (as opposed to mRNA) to CD3+ cells is attributed to the inability of T lymphocytes to store and concentrate sufficient intracellular amounts of these cytokines to produce positive immunostaining.

Enhanced expression of high-affinity IgE receptor (Fc epsilon RI) alpha chain in human allergen-induced rhinitis with co-localization to mast cells, macrophages, eosinophils, and dendritic cells.

BACKGROUND: IgE-dependent activation of mast cells and basophils through the high-affinity IgE receptor (Fc epsilon RI) is involved in the pathogenesis of allergen-induced immediate and late responses. OBJECTIVE: We investigated the expression and cellular distribution of Fc epsilon RI in the nasal mucosa after allergen challenge in patients with summer hay fever. METHODS: Fourteen grass pollen-sensitive patients and seven normal control subjects underwent nasal challenge with grass pollen and allergen diluent in random order separated by 2 weeks. Nasal airway caliber was monitored by acoustic rhinometry, and nasal biopsy was performed at 6 hours. Messenger RNA for Fc epsilon RI was determined by using reverse-transcription polymerase chain reaction, and Fc epsilon RI protein expression was determined by immunohistology with a mouse monoclonal antibody (22E7) and a rabbit polyclonal antibody (997) directed against the alpha subunit. Co-localization of Fc epsilon RI receptors was performed by using double-immunostaining methods. RESULTS: In atopic subjects, there was a significant early decrease in nasal airway caliber, which extended up to 6 hours after allergen challenge. Fc epsilon RI mRNA levels were elevated at 6 hours (p = 0.03). Cells expressing Fc epsilon RI protein were increased in patients with atopic rhinitis compared with normal control subjects (p = 0.03). Further increases in Fc epsilon RI+ cells were observed after allergen challenge only in the atopic group (p = 0.02). Double immunohistochemistry revealed that the majority of Fc epsilon RI+ cells were mast cells (64%), followed by macrophages (20%), eosinophils (4%), and dendritic cells (2%), with 10% Fc epsilon RI+ cells being unidentified. CONCLUSIONS: Our results demonstrate increased Fc epsilon RI expression during allergen-induced rhinitis and highlight a potential target for treatment.

RANTES in human allergen-induced rhinitis: cellular source and relation to tissue eosinophilia.

Human allergen-induced rhinitis is associated with recruitment and activation of CD4+ T lymphocytes and eosinophils. RANTES is a novel CC chemokine that is a potent chemoattractant for both memory T cells and eosinophils. We therefore investigated RANTES in the nasal mucosa after local allergen provocation. Nasal lavage was performed, and biopsies from the inferior nasal turbinate were taken from 14 atopic, seasonal rhinitic patients and seven normal subjects for as long as 6 h after challenge with a grass pollen extract and after a control (allergen diluent) challenge. In five of seven rhinitics tested, radioimmunoassay of nasal fluid demonstrated increases in RANTES at 2 to 4 h (p < 0.05). Nasal allergen challenge provoked significant increases in RANTES mRNA (p = 0.0015) and protein (p = 0.01) containing cells in the nasal submucosa at 6 h. No changes were observed in normal subjects. Increases in RANTES mRNA+ cells correlated with the associated increases in eosinophils (r = 0.78, p = 0.001). Colocalization studies revealed that the majority of RANTES mRNA+ cells were macrophages (51%) followed by eosinophils (15%), T lymphocytes (11%), and mast cells (3%). Our results demonstrate that allergen-induced rhinitis is associated with release of RANTES and upregulation of RANTES mRNA and protein+ cells, predominantly macrophages, in the nasal mucosa. RANTES synthesis, release, or receptor antagonism may represent a potential target for antiallergy treatment.

Nasal nitric oxide is increased in patients with asthma and allergic rhinitis and may be modulated by nasal glucocorticoids.

Nitric oxide (NO) is produced in large amounts in the noses of normal individuals. We have measured NO by chemiluminescence in the noses and exhaled air of subjects with symptomatic allergic rhinitis, some of whom had concomitant asthma, during the pollen season and compared this with values measured in normal subjects and in patients treated with nasal and/or inhaled glucocorticoids. We found that nasal levels of NO were significantly (p < 0.001) elevated in patients with untreated rhinitis (1527 +/- 87 ppb, n = 12) compared with normal individuals (996 +/- 39 ppb, n = 46) or subjects treated with nasal steroids (681 +/- 34 ppb, n = 10), whereas exhaled NO in patients with untreated rhinitis was similar to that in normal subjects (10 +/- 2 ppb vs 7 +/- 0.6 ppb, respectively). In five subjects who were nasally challenged with allergen, there was a significant decrease in nasal NO 1 hour after challenge, and this was significantly correlated with increased rhinitis symptoms. In patients with rhinitis and concomitant asthma, nasal NO was also significantly elevated (1441 +/- 76 ppb, n = 16) but not when they were treated with nasal or inhaled steroids; whereas exhaled NO was elevated in untreated patients and in patients treated with nasal, but not inhaled, steroids. Our data suggest that the increase in exhaled NO in patients with allergic rhinitis is likely to be due to increased local production, caused by long-term exposure to allergen, which is suppressed by locally administered steroids. Measurement of nasal NO may be useful to study the inflammatory response in rhinitis and its response to antiinflammatory treatments.

Effect of thromboxane A2-receptor antagonist on bradykinin-induced bronchoconstriction in asthma.

The role of the thromboxane A2 (TxA2) receptor in bradykinin-induced bronchial responses was investigated in this study by using a selective and potent TxA2-receptor antagonist BAY u 3405. Eleven asthmatic subjects were randomized to receive 50 mg of BAY u 3405 or matched placebo in a crossover and double-blind fashion. Ninety minutes after dosing, serum was taken for drug assay, and subjects underwent provocation with bradykinin or prostaglandin D2 (PGD2) to determine bronchial responsiveness [provocative concentration of agonist required to produce a 20% fall in forced expiratory volume in 1 s from the postdiluent baseline (PC20)]. Pretreatment with BAY u 3405 caused a twofold doubling-dilution reduction in bronchial reactivity to PGD2; the geometric mean PC20 values were 0.132 (0.015-0.871) and 0.034 (0.008-0.095) mg/ml, respectively, for active and placebo days (P = 0.001). There was, however, no significant difference in PC20 values for bradykinin between active and placebo treatment days. We have demonstrated that BAY u 3405 caused a significant inhibition of bronchconstriction induced by inhaled PGD2 but had no influence on bronchial responsiveness to inhaled bradykinin. This study suggests therefore that TxA2 receptors do not play a role in bradykinin-induced bronchoconstriction in asthma.

Cross refractoriness between bradykinin and hypertonic saline challenges in asthma.

BACKGROUND: Repeated inhalation of bradykinin and hypertonic saline leads to refractoriness of the bronchoconstrictor response in asthma. It is not known whether cross-refractoriness exists between these stimuli. OBJECTIVE: We postulated that repeated bradykinin and hypertonic saline bronchial challenges might reduce the airway response to subsequent hypertonic saline and bradykinin challenges, respectively. METHODS: Eleven atopic asthmatic subjects underwent two concentration-response studies, separated by 1 hour, with either inhaled histamine or bradykinin. After recovery, a hypertonic saline challenge was performed. During the next phase, nine subjects underwent two concentration-response studies, separated by 1 hour, with hypertonic saline. After recovery, a bradykinin challenge was performed. RESULTS: On the histamine study day, the mean provocative volume of agonist required to produce 20% drop in forced expiratory volume in 1 second (PD20) hypertonic saline was 220.7 L (+/- 42.7 L) and this was not significantly different from that measured at baseline. On the bradykinin study day, the geometric mean provocative concentration of agonist required to produce a 20% drop in forced expiratory volume in 1 second (PC20) was 0.39 mg/ml (0.01 to 11.73 mg/ml) for the first test and significantly higher at 1.38 mg/ml (0.01 to > 16.0 mg/ml) for the second test (p = 0.006). The hypertonic saline PD20 increased significantly from a baseline of 159.2 L (+/- 27.3 L) to 377.6 (+/- 64.7 ) (p = 0.003). On the hypertonic saline study day, the mean PD20 was 152.8 L for the first test, and 337.7 L for the second test (p = 0.01). PC20 bradykinin increased significantly from a baseline of 0.57 to 2.56 mg/ml (p = 0.02). A significant correlation was found between loss of response to bradykinin and to hypertonic saline (rs, 0.63 and 0.76). CONCLUSION: Refractoriness produced by repeated exposure of the airways to bradykinin and hypertonic saline results in loss of responsiveness to hypertonic saline and bradykinin respectively, suggesting a shared mechanism for refractoriness produced by these stimuli.

Inhaled loop diuretics and basal airway responsiveness in man: evidence of a role for cyclo-oxygenase products.

Inhaled frusemide protects asthmatic airways against a wide variety of bronchoconstrictor stimuli by unknown mechanisms. To investigate whether inhaled loop diuretics modulate baseline bronchial responsiveness, a randomized, double-blind, placebo-controlled study was conducted to test the ability of frusemide (40 mg) and bumetanide (2 mg) to displace concentration-response curves with methacholine in 14 healthy volunteers. In addition, separate randomized, double-blind studies were carried out to evaluate the effects of oral flurbiprofen, a potent cyclo-oxygenase inhibitor, on the protective action of frusemide against methacholine-induced bronchoconstriction. Inhaled loop diuretics significantly increased the provocative concentration of methacholine causing a 15% decrease in forced expiratory volume in one second (PC15FEV1) from the geometric mean (range) value of 58.6 (9.2-233) mg.ml-1 after placebo administration, to 129 (13.8-505) and to 106 (6.6-510) mg.ml-1 after administration of frusemide and bumetanide, respectively. Similar results were obtained when data from partial flow-volume curves were used for analysis. In the eight subjects studied, pretreatment with oral placebo and inhaled frusemide reduced airway responsiveness to methacholine, with a geometric mean (range) PC15FEV1 value of 116 (25.4-405) mg.ml-1, and premedication with oral flurbiprofen abolished this protective effect, the geometric mean (range) PC15FEV1 methacholine being reduced to a value of 50.3 (16.6-189) mg.ml-1. In addition, oral flurbiprofen alone failed to alter airway responsiveness to methacholine. In view of these findings, it is suggested that bronchoprotective prostaglandins may mediate the effects of loop diuretics against methacholine-induced bronchoconstriction in man.