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Biomedical subjects

F Ruëff

Publications and source records attributed to F Ruëff.

At least 19 recordsLinked to original sources
PubMed2005

Possible circadian variation of serum mast cell tryptase concentration.

BACKGROUND: A temporarily elevated level of serum mast cell tryptase (ST) indicates mast cell activation and occurs in systemic anaphylactic reactions (SAR). We measured ST following a sting challenge in vespid venom-allergic patients treated with venom immunotherapy (VIT) and in healthy controls, respectively. AIM OF THE STUDY: To assess changes of ST over time in vespid venom-allergic patients at the occasion of a re-sting and in healthy controls. METHODS: A sting challenge was performed in 20 patients on vespid VIT to monitor efficacy of VIT. ST was measured between 9.00 and 10.00 a.m. (baseline). Sting challenge was performed at 2.00 p.m., and ST was determined again 20 min, 90 min and 18 h later. Measurements at corresponding times of the day were done in nine healthy controls. RESULTS: One patient developed a mild SAR to the sting challenge which was associated with a temporary increase of ST. In the other 19 patients who tolerated the sting challenge without SAR ST decreased significantly by 18.0% (median, range 8.3-36.7%). Twenty minutes after the sting when compared with baseline levels (P < 0.001), a significant decrease of ST was still present after 90 min (median 13.7%) (P < 0.001), but not after 18 h (P = 0.57). A comparably significant temporary decline was found in controls. CONCLUSIONS: The temporary decline of ST in patients and in controls suggests a circadian variation of ST concentration. A normal diurnal pattern of ST concentration after sting challenge is associated with successful treatment.

Adolescent↗
PubMed2004

[Emergencies in allergology].

The clinical presentation of allergological emergencies is heterogeneous. The most important conditions are anaphylaxis (which is frequent) and Stevens-Johnson syndrome or toxic epidermal necrolysis (which are rare). In the acute phase it is most important to recognize the exogenous elicitation of the condition as soon as possible, otherwise severe sequelae, even death of the patient, may occur. Management is based on immediate elimination of possible causative agents and symptomatic therapeutic measures. Furthermore, allergological diagnostics are necessary without delay to identify what has elicited the reaction. This information makes possible long-term treatment in order to avoid further hypersensitivity reactions.

Anaphylaxis↗
PubMed2004

Specific immunotherapy in honeybee venom allergy: a comparative study using aqueous and aluminium hydroxide adsorbed preparations.

BACKGROUND: For the immunotherapy of Hymenoptera venom allergy various preparations and treatment protocols are in use. However, controlled studies making direct comparisons of the efficacy and safety of different regimens are rare. OBJECTIVE: To assess prospectively different venom immunotherapy (VIT) protocols using an aqueous or an aluminium hydroxide adsorbed allergen preparation for the treatment of honeybee venom (HBV) allergy. METHODS: Sixty-five HBV allergic patients (42 males, 23 females; aged 17-75 years) with a history of systemic anaphylactic reactions (SARs) to honeybee stings were treated according to three different regimens. During the incremental phase, patients in group A (n = 21) or B (n = 21) received an aqueous preparation according to a rush protocol. Patients in group C (n = 23) were treated with conventional ("slow") VIT using an aluminium hydroxide adsorbed depot preparation. The maintenance dose was 100 microg venom in all groups. Maintenance treatment in group A was performed with the aqueous preparation administered every 4 weeks, whereas in groups B and C the depot preparation was administered every 8 weeks (group B) or every 4 weeks (group C). A sting challenge test with a living honeybee was performed in 49 patients, 6-12 months after reaching the maintenance dose. Another seven patients were stung accidentally by a honeybee ("field sting"). RESULTS: Treatment with the aqueous preparation evoked large local reactions more frequently than the depot preparation in the dose increase phase [53/693 (7.6%) vs 8/206 (3.9%); P = 0.059] and also in the course of maintenance therapy [85/172 (49.4%) vs 58/478 (12.1%); P < 0.001]. During the dose increase phase, systemic side-effects seemed to occur more frequently in patients on rush VIT with the aqueous preparation compared to patients initially treated with the conventional schedule using the depot preparation [13/42 (31.0%) vs 3/23 (13.0%); not significant). When re-stung by the culprit insect, SARs were observed in 3/20 patients (15.0%) in group A, 2/18 (11.1%) in group B and 3/18 (16.7%) in group C (not significant). CONCLUSIONS: The aluminium hydroxide adsorbed HBV preparation caused fewer large local reactions than the aqueous preparation. The therapeutic efficacy of the three treatment protocols did not differ.

Adolescent↗
PubMed2001

Detection of trace amounts of hidden allergens: hazelnut and almond proteins in chocolate.

Many patients with immediate type allergy to tree pollen also suffer from intolerance to hazelnuts and almonds. Since rather low levels of hazelnut and almond proteins can provoke an allergic reaction in sensitized individuals, an immunoblot technique has been developed for the detection of potentially allergenic hazelnut and almond proteins in chocolate. Initially, IgE binding hazelnut and almond proteins were detected by immunoprobing with allergic patients' sera. For routine analysis, patients' sera were substituted with polyclonal rabbit antisera, and sensitivity was enhanced by the use of a chemiluminescent detection method. This technique allowed the detection of less than 0.5 mg of hazelnut or almond proteins per 100 g of chocolate (= 5 ppm). It was applied for routine screening purposes in product quality control as well as for optimization of cleaning steps of filling facilities to minimize cross contamination during production.

Allergens↗
PubMed2001

Constitutively raised serum concentrations of mast-cell tryptase and severe anaphylactic reactions to Hymenoptera stings.

Anaphylactic IgE-mediated reactions to Hymenoptera stings vary in their severity for reasons that are not clear. We investigated patients with a history of systemic anaphylatic reactions to honeybee or wasp stings. Nine (75%) of 12 patients with raised tryptase concentrations but only 28 (28%) of 102 patients with lower tryptase concentrations, had a history of severe sting reactions (p=0.004). Raised baseline serum concentrations of mast-cell tryptase and mastocytosis are potential risk factors for severe allergic reactions to Hymenoptera venom.

Adult↗
PubMed2001

Frequency of natural rubber latex allergy in adults is increased after multiple operative procedures.

BACKGROUND: It has been shown that immediate-type allergy to natural rubber latex (NRL) affects predominantly health-care workers and infants with malformations requiring repeated medical procedures. Adult patients with multiple invasive procedures are not thought to be at an increased risk of NRL allergy. METHODS: A total of 325 consecutive adult inpatients (54.4+/-15.6 years; 219 men, 106 women) awaiting surgical or urologic procedures were assessed by questionnaire-based history (atopic diseases, number of previous standard operative or endoscopic procedures, intolerance to rubber products, and adverse reactions during medical care), by skin prick tests with different NRL test solutions, by measurement of NRL-specific IgE in the serum, and, if sensitization to NRL was found, by cutaneous challenge tests with NRL-containing material. Subjects were classified as sensitized to NRL if skin prick test reactions to NRL were positive or if NRL-specific IgE antibodies were found. NRL allergy was defined as NRL sensitization and immediate-type symptoms to NRL. RESULTS: Thirty-one of 325 (9.5%) subjects were found to be sensitized to NRL, 14/285 (4.9%) by skin prick testing and 23/323 (7.1%) by NRL-specific IgE antibodies in the serum. Four individuals (1.2%) were diagnosed as having clinically manifest NRL allergy, and another 27 (8.3%) were sensitized to NRL without symptoms to date. The frequency of previous invasive procedures was zero in eight patients, up to 10 in 245, 11-20 in 52, 21-30 in seven, and over 30 (up to 83) in 13 patients. No association was found between the number of invasive procedures and NRL sensitization without clinical symptoms. However, 3/4 patients with NRL allergy had undergone more than 30 interventions, and 1/4 had had 11 operations. Frequent invasive procedures (more than 10) were significantly associated with NRL allergy (P<0.001). Allergy or sensitization to NRL was associated with atopy (21/31 vs 87/294) (P<0.001). CONCLUSIONS: A remarkable percentage of unselected adult patients undergoing surgical procedures have allergy or sensitization to NRL. Repeated invasive treatment appears to be a risk factor for NRL allergy.

Adult↗
PubMed2001

Patients still reacting to a sting challenge while receiving conventional Hymenoptera venom immunotherapy are protected by increased venom doses.

BACKGROUND: Up to 20% of patients allergic to Hymenoptera venom are not protected by conventional venom immunotherapy (VIT) with 100 microg of any single venom. OBJECTIVE: We sought to evaluate the efficacy of an increased venom dose in patients allergic to Hymenoptera venom still reacting systemically to a sting challenge despite immunotherapy with 100 microg of venom every 4 weeks. METHODS: In this retrospective study patients were included who still had reacted systemically to a sting challenge with a living bee or wasp despite VIT with a maintenance dose of 100 microg every 4 weeks. The maintenance dose was increased to 150 or 200 microg every 4 weeks, and a second sting challenge was performed. If a patient reacted again, the dose was further increased. Baseline mast-cell tryptase levels were assessed by using a fluoroenzyme immunoassay in stored patient sera. RESULTS: While receiving a maintenance dose of 100 microg of venom every 4 weeks for 7 to 38 months, 18 patients reacted systemically to a bee sting and 22 reacted to a wasp sting. After an increase of the maintenance dose to 150 microg, 2 of 4 patients allergic to bee venom (BV) and 6 of 6 patients allergic to yellow jacket venom (YJV) no longer reacted systemically to the sting challenge. The respective rates of full protection were 13 of 14 and 15 of 16 in patients with an increase of the maintenance dose to 200 microg from the start. Of those 4 individuals not protected by the first dose increase, one patient allergic to BV (prior dose of 150 microg) and one patient allergic to YJV (prior dose of 200 microg) did not react systemically to a further sting challenge while receiving 200 microg of BV or 250 microg of YJV, respectively. One patient allergic to BV who had a systemic reaction to the sting challenge while receiving 150 microg was not protected after a dose increase to 200 microg; she later received a dose of 400 microg of BV, and no further sting challenge was performed. The patient allergic to BV who still reacted systemically after a first dose increase to 200 microg was a female patient with urticaria pigmentosa. She had repeated systemic adverse reactions to further BV immunotherapy, necessitating discontinuation of the treatment; however, she tolerated well VIT with 200 microg of YJV. In all other patients, no unusual adverse reactions to the increased venom doses were observed. Baseline serum tryptase levels were elevated above 13.5 microg/L (95th percentile in normal subjects) in 9 (28.1%) of 32 patients. CONCLUSIONS: The majority of patients allergic to Hymenoptera venom who still reacted systemically to a sting challenge despite VIT with a dose of 100 microg every 4 weeks can be fully protected by an increased maintenance dose. This dose increase is well tolerated by most patients. The rather high proportion of patients with elevated baseline serum tryptase levels necessitates further investigation of a possible association between mastocytosis and treatment failure of conventionally dosed VIT.

Adult↗
PubMed2001

[Anaphylactic reaction to Ficus benjamina (weeping fig)].

Ficus benjamina (weeping fig) is a widespread indoor ornamental plant. Allergens of Ficus benjamina are a well-known cause of IgE-mediated respiratory diseases. We treated a 32-year-old female who for 10 years had suffered from perennial rhinoconjunctivitis. When dusting her 2 meter high Ficus benjamina, she developed an anaphylactic reaction which resolved without sequelae. Skin prick testing revealed a strong immediate type reaction to a Ficus extract, the serum concentration of specific IgE-antibodies to Ficus was > 100 kU/I (CAP class 6). In view of these strong test reactions and the conclusive history, no challenge tests with Ficus allergens were performed. After removal of the Ficus plants which she had owned for 17 years and after thorough cleaning of her dwelling, the patient's symptoms of perennial rhinoconjunctivitis stopped. The patient also was sensitized to, but not allergic to natural rubber latex, which occurs frequently in Ficus allergy and probably is due to cross reactivity to allergens from both sources. As Ficus benjamina is an important source of indoor allergens, it should not be used in dwellings or work places.

Adult↗
PubMed1999

[Exertion-induced anaphylaxis after eating pork and beef].

HISTORY AND CLINICAL FINDINGS: A 72-year-old woman developed generalized urticaria. Quincke oedema, shortness of breath and hypotension two hours after eating a meal containing pork and after mild physical activity (ironing) in-between. She was treated by an emergency physician and then admitted to hospital for one day of monitoring her condition. During the past several years such episodes of generalized urticaria had recurred twice to four times a year. INVESTIGATIONS: Pin-prick tests gave an immediate-type reaction to beef but not to pork. Specific serum IgE antibodies were demonstrated to pork and beef, cat's epithelia, milk albumin and casein. Oral provocation tests were negative for pork and beef. But when pork and beef were eaten mild physical activity (bicycle ergometry at 20 W), generalized urticaria occurred after eating pork and beef, but not after drinking milk. TREATMENT AND COURSE: Exercise-induced anaphylaxis to pork and beef was diagnosed. No allergic reaction has occurred in more than 12 months of avoiding eating these meats. CONCLUSION: The picture of exercise-induced anaphylaxis caused by food allergy can be precipitated by even mild activity. This must be taken into account in the diagnosis of systemic rapid-reaction response and in the performance of provocation tests.

Aged↗