B. Guérin

Allergy in the Mediterranean area I. Pollen counts and pollinosis of Montpellier

The climatic conditions of the Mediterranean area results in vegetation and pollen very different from that of the other parts of Europe. The pollen content of the atmosphere of Montpellier, southern France, was examined using a filter sampler which was shown to be more efficient than most of the current devices for air sampling. Pollen counts were subsequently compared with pollinosis of patients born and living in and around Montpellier. The mean annual pollen counts showed that grass pollens and Cupressaceae pollens (cypress and juniper) are the highest. Some Mediterranean pollens (Oleaceae, London plane, Parietaria) are also important. Plantain and oak pollens are also present in relatively large amounts.

Immunotherapy with a standardized Dermatophagoides pteronyssinus extract: I. In vivo and in vitro parameters after a short course of treatment

Dermatophagoides pteronyssinus (Dp) is the major allergen in allergic asthma in France. Standardized and lyophilized Dp extracts are available, and their effectiveness after a short course of rush immunotherapy was examined in a placebo-controlled, double-blind study. Twenty patients received the Dp standardized extract, and 10 other patients received a placebo extract. Before and 7 weeks after rush immunotherapy, in vivo and in vitro parameters were examined. Bronchial provocation tests performed in a standardized manner demonstrated that a provocative dose causing a 20% fall in FEV1, a 25% fall in maximum mild expiratory flow rate, a 25% fall in maximum flow when 50% of the forced vital capacity has been expired, and a 35% fall in specific airway conductance were significantly (p less than 0.005 to p less than 0.01, Wilcoxon W test) improved in the treated group and remained unchanged in the placebo group. Skin test titration demonstrated that patients placed in the treated group had a significant (p less than 0.001, Wilcoxon W test) decrease of both end point titer and size of the largest wheal. No significant difference was observed in the placebo group. Serum Dp-IgE did not vary significantly in either group. Serum Dp antigen P1-IgG was significantly (p less than 0.001, Wilcoxon W test) increased in the treated group and slightly increased in the placebo-treated group. This study demonstrated that a Dp standardized extract administered by a rush protocol elicits a rapid and significant immune response and leads to a significant protection of the patients.

Allergy in the Mediterranean area III: cross reactivity among Oleaceae pollens

Pollens of closely related species often share common antigens and allergens although this is not always the case. Four species of Oleaceae pollens commonly found in the Mediterranean area were investigated For cross‐reactivity: olive (Olea europaea), ash (Fraxinus exselsior), privet (Ligustrum vulagare) and Phillyreu augustifolia, a common bush. Twenty individual sera of patients allergic to Oleaceae were investigated for specific IgE antibodies against the four species of Oleaceae pollens. The results indicated a high degree of correlation between RAST titres of Oleaceae pollens but three gave a particular emphasis on one species only. Cross‐reactivity among these four pollen species was sought by means of RAST inhibition, iso‐electric focusing and tandem cross‐immunoelectrophoresis. All tests revealed a high degree of cross reactivity although there is no total identity among these four pollen species.

Specific immunotherapy with a standardized Dermatophagoides pteronyssinus extract. II: Prediction of efficacy of immunotherapy

House dust mites of the species Dermatophagoides pteronyssinus (Dpt) represent one of the major allergens inducing asthma. However, a strict allergy to Dpt is not always observed in Dpt-allergic patients, since nonallergic and other allergic triggering factors often coexist. It was suggested that specific immunotherapy with house dust-mite extracts is more effective in children than in adults. A controlled study was undertaken in 215 Dpt-allergic patients with asthma ranging in age from 3 to 72 years (mean +/- SD, 28.2 +/- 10.9 years) to investigate parameters that might predict the efficacy of specific immunotherapy before it is started; 171 patients received a rush immunotherapy protocol with a standardized Dpt extract and, subsequently, maintenance injections with 3000 BU of this extract, and 44 patients served as a control group. Before immunotherapy, all patients had a complete evaluation of the severity of asthma by symptom-medication scores and a pulmonary function test, as well as a study of other triggering factors by checking on seasonal and perennial allergens, sinusitis, and other possible causes, such as aspirin intolerance; 196 patients were investigated between 9 and 12 months after the onset of the survey by means of pulmonary function tests and symptom-medication scores. Medications were adapted according to peak flow rates. It was observed that patients with chronic sinusitis, and/or aspirin intolerance, and/or other perennial allergies did not benefit from specific immunotherapy; therefore, the treatment of a major etiologic factor did not demonstrate improvement in the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Double-blind, placebo-controlled immunotherapy with mixed grass-pollen allergoids: I. Rush immunotherapy with allergoids and standardized orchard grass-pollen extract

Forty-five grass pollen-allergic patients were randomly assigned to three groups according to their skin test and RAST sensitivities and the severity of seasonal rhinitis. Eleven patients were treated with placebo (group 1), 19 patients (group 2) were treated with a six-mixed grass-pollen allergoid prepared by mild formalinization with a two-step procedure, and 15 other patients were treated with a standardized orchard grass-pollen extract (group 3). Because of a different immunotherapy schedule, only patients placed in groups 1 and 2 received the extracts in a double-blind fashion. Rush immunotherapy was performed in 3 to 6 days, and the maintenance dose was subsequently administered weekly for 4 weeks and every 2 weeks until the end of the grass-pollen season. During the season, a coseasonal treatment was administered. Systemic reactions occurred during the rush protocol in 36.8% of patients treated with allergoid and 20% of patients who received the standardized extract. Only patients treated with allergoid had systemic reactions during maintenance dose. The reactions observed with the standardized extract were more severe. Total doses of allergoid ranged from 2350 to 13,500 protein nitrogen units. Symptoms and medication scores during the peak of the season were analyzed. Patients treated with the standardized allergen had a significant reduction of the number of days of symptoms during the month of June (9.5 +/- 6.7 days; p less than 0.005) and of medication scores (1.3 +/- 1.4; p less than 0.01) compared to patients receiving placebo (19.4 +/- 8.1 days; medication score, 2.8 +/- 2.1).(ABSTRACT TRUNCATED AT 250 WORDS)

Comparison of the stability of a mite and a pollen extract stored in normal conditions of use

Pollen extracts are stable in solutions containing 50% glycerol. The stability of Dermatophagoides pteronyssinus (Dp) extracts have not been determined. Two lyophilised extracts (Dp and cocksfoot pollen) were reconstituted in 50% glycerol and stored for up to 6 months at +4°C. Every day the extracts were placed at room temperature for 1 hr to mimic the natural use of allergen extracts by allergists. Every 2 months the extracts initially prepared were compared to freshly reconstituted extracts by means of prick skin tests in fifteen allergic patients. It was observed that cocksfoot pollen extract is stable but there appears a slight but significant (P > 0.05) decay in activity when the extract stored for up to 6 months was compared with a freshly prepared extract. On the other hand there is a significant (P > 0.01) decay in activity of the Dp extract after 2 months of storage. Dermatophagoides pteronyssinus and cocksfoot pollen extracts behave differently when stored. These findings have particular importance in the diagnosis and treatment of allergic disorders.

Comparison between rush immunotherapy with a standardized allergen and an alum adjuved pyridine extracted material in grass pollen allergy

Rush immunotherapy with a standardized and lyophilized cocksfoot pollen extract was performed in twenty‐three allergic subjects and compared with classical immunotherapy done with an alum adjuved, pyridine extracted cocksfoot pollen extract (fifteen subjects) and a control group of ten patients. The three groups were perfectly matched. Clinical benefits were analysed by means of symptom scores. It was shown that rush immunotherapy gave significantly better results when asthma or rhinitis was considered than either classical immunotherapy (P>0.02) or in the control group (P>0.01 and 0.02). Skin tests were significantly reduced after rush immunotherapy and did not change in the two other groups. After the pollen season the skin test reactivity was increased in the rush immunotherapy group. Cocksfoot pollen specific IgE did not vary significantly in the three groups. Cocksfoot pollen specific IgG was significantly (P>0.05) increased in the rush immunotherapy group before the pollen season and did not vary significantly in the other groups.

Allergy in the Mediterranean area II: cross-allergenicity among Urticaceae pollens (Parietaria and Urtica)

Pollens of related species usually share common antigens and are cross‐reacting but this is not always the case. The cross‐allergenicity of two species of Urticaceae pollens (Parietaria and Urtica, nettle) was sought by means of RAST‐inhibition and isoelectric focusing. A preliminary experiment in forty‐two patients investigated by means of skin tests and RAST showed that most patients were either allergic to Parietaria or nettle and that both reactivities were uncommonly associated. The results of RAST‐inhibition confirmed the total absence of cross‐reactivity between these two related species. IEF patterns indicated that most proteins are in the acidic range of pH and did not reveal large discrepancies. Parietaria and Urtica pollens, although belonging to the same family and having close microscopic patterns, have very different allergenic activities. This study demonstrates that cross‐allergenicity cannot be predicted.

Systemic reactions to the Samsum ant: An IgE-mediated hypersensitivity

BACKGROUND In the United Arab Emirates the sting of the Pachycondyla sennaarensis ant (PSA) causes allergic reactions in certain persons. It is a common problem and is becoming a public health hazard. Up to now the diagnosis has been based only on the history, because the mechanism of the reaction was not yet established. OBJECTIVE The aim of our study was to prepare an allergenic extract that would be used for skin tests and to prepare a reagent for specific IgE titration. Results of both skin tests and specific IgE were to be compared with the clinical history. METHODS We studied 31 patients with anaphylactic reactions and performed clinical examinations, skin tests, and specific IgE antibody titrations. A control group of 22 subjects were also studied. RESULTS In 30 of 31 patients (97%) findings of PSA skin tests and/or specific IgE were positive. In the control groups PSA skin test results were negative in 86% and negative for specific IgE in 68%. CONCLUSION The study shows that the mechanism of the reaction to the sting of the PSA is a type I IgE-mediated hypersensitivity and that the diagnosis can now be confirmed by skin tests and specific IgE determination.

In vitro evaluation of acaricidal and fungicidal activity of the house dust mite acaricide, Allerbiocid

The acaricidal and fungicidal activities of a new acaricide Allerbiocid, formulated for the control of house dust mites, were investigated. The components of the Allerbiocid formula are: 3% benzyl benzoate (acaricidal and fungicidal), 1% tannic acid (protein denaturant) and 0.5% Tween (surface active agent) in 70% isopropyl alcohol (antiseptic). At application rates of both 150 and 250 ml/m2, the acaricidal activity appeared to work by both ingestion and contact and remained active upon contact with mites for up to 10 weeks. When Sabouraud agar was treated with Allerbiocid at a concentration of 5 ml/20 ml medium, the preparation was also found to have fungicidal and fungistatic activities on various species of fungi commonly found in house dust. Allerbiocid contains tannic acid which is a protein denaturant. Levels of Der p I in dust were found to be reduced by over 90% after treatment with Allerbiocid. The importance of denaturation of mite faecal allergens and allergens associated with dead fungal spores is discussed.