Hypersensitivity to Hymenoptera venom: advances in diagnosis and implications for treatment

Diagnosis and treatment of hypersensitivity to Hymenoptera venom took a landmark step forward in the late 1970s with the introduction of venom as an adequate material instead of whole body extracts. Since then, venom immunotherapy (VIT) has provided allergic subjects with a complete protection from fatal anaphylaxis and prevented about 90% of all reactions to stings. The cross-reactivity among some venom components, particularly important in the case of cross-reacting carbohydrate determinants, has often made it difficult to recognize the true causative venom to be used in VIT. Recently, the introduction of purified and recombinant allergens, such as Api m 1 from honeybee venom, Ves v 5 from yellow jacket venom, and Pol d 5 from wasp venom, have allowed a more precise diagnosis with identification of the causative venom component. This paves the way for a patient-tailored VIT in the near future. Another issue which needs to be addressed is the improvement in the safety of VIT with honeybee venom, which is significantly less favourable in comparison to vespid venom. A number of molecular approaches are under investigation in order to achieve this objective. Alternative routes of administration, such as the sublingual and the intralymphatic, have also been proposed, but there are not yet sufficient data available to demonstrate their feasibility. This review also presents patents on new trends in therapies for the management of hypersensitivity to hymenoptera venom.

Birch-apple syndrome treated with birch pollen immunotherapy

BACKGROUND

The most common pollen-fruit cross-reaction is the birch-apple syndrome. Allergen immunotherapy (IT) is clearly effective for birch allergy, but its efficacy on apple allergy is controversial. We performed a randomized study on patients with birch-apple syndrome to evaluate the outcome of subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT).

METHODS

Forty patients underwent IT with a birch extract (Staloral; Stallergenes, Antony, France), 20 by SCIT and 20 by SLIT. After 1 year of treatment, 15 patients (8 for SCIT and 7 for SLIT) accepted to undergo an oral apple challenge. Measurements of specific IgE to Bet v 1 and Mal d 1 and related allergens Api g 1 and Dau c 1 were obtained in 10 patients, at baseline and after IT.

RESULTS

Two of 8 SCIT-treated patients (25%) and 1 of 7 SLIT-treated patients (14.2%) developed complete tolerance to apple. In the remaining patients, an increase in the provocative dose was found in 3 of the SCIT-treated (37.5%) and 2 of the SLIT-treated patients (28.6%). Changes in the levels of specific IgE to Mal d 1 were unrelated to clinical results.

CONCLUSIONS

These findings suggest that different doses of birch extract may be needed in different patients to improve the associated apple allergy and that a finer diagnostic work-up in selecting patients with birch-apple syndrome who are candidates to respond to birch pollen IT also concerning apple allergy is required.

Long-lasting genomic instability following arsenite exposure in mammalian cells: the role of reactive oxygen species

Previously, we reported that the progeny of mammalian cells, which has been exposed to sodium arsenite for two cell cycles, exhibited chromosomal instability and concurrent DNA hypomethylation, when they were subsequently investigated after two months of subculturing (about 120 cell generations) in arsenite-free medium. In this work, we continued our investigations of the long-lasting arsenite-induced genomic instability by analyzing additional endpoints at several time points during the cell expanded growth. In addition to the progressive increase of aneuploid cells, we also noted micronucleated and multinucleated cells that continued to accumulate up to the 50th cell generation, as well as dicentric chromosomes and/or telomeric associations and other complex chromosome rearrangements that began to appear much later, at the 90th cell generation following arsenite exposure. The increasing genomic instability was further characterized by an increased frequency of spontaneous mutations. Furthermore, the long-lasting genomic instability was related to elevated levels of reactive oxygen species (ROS), which at the 50th cell generation appeared higher than in stable parental cells. To gain additional insight into the continuing genomic instability, we examined several individual clones isolated at different time points from the growing cell population. Chromosomally and morphologically unstable cell clones, the number of which increased with the expanded growth, were also present at early phases of growth without arsenite. All genomically unstable clones exhibited higher ROS levels than untreated cells suggesting that oxidative stress is an important factor for the progression of genomic instability induced by arsenite.

Current and future applications of the anti-IgE antibody omalizumab

IgE antibodies are a pivotal factor in pathophysiology of allergic diseases, and the possibility of reducing their level by anti-IgE has long been envisioned. Following several attempts, an effective biologic agent was obtained with the recombinant humanized mono-clonal antibody (rhuMAb)-E25, known as omalizumab. A number of controlled clinical trials demonstrated its efficacy and safety in the treatment of severe allergic asthma uncontrolled by standard drug treatment with maximal recommended doses, and treatment with omalizumab is currently included in international guidelines on asthma management. Other studies reported a clear effectiveness also in allergic rhinitis, but the cost of the anti-IgE treatment suggests its use in patients with rhinitis concomitant with asthma. Other indications to be further investigated are skin disorders such as atopic dermatitis and IgE-mediated urticaria, as well as adverse reactions to foods, with a particularly important role in preventing food-induced anaphylaxis. Finally, there are data indicating the usefulness of omalizumab when used in combination with allergen specific immunotherapy, in terms of reducing the adverse reactions to treatment and increasing the clinical efficacy.

Anaphylaxis: an update on its understanding and management

Anaphylaxis is the most concerning manifestation of hypersensitivity. Recent thorough investigations on the pathophysiology of anaphylaxis achieved important advances in its understanding, regarding in particular the emerging role of mediators such as platelet activating factor (PAF) and sphyngosine 1 phosphate (S1P) and the improved knowledge on the actors of the signaling cascade, from the contact between the specific allergen and the IgE fixed on the Fc-epsilon-RI receptor to the opening of calcium channels. These advances may provide new diagnostic and therapeutical tools. In particular, a role for PAF and S1P as laboratory markers of anaphylaxis is likely to be developed, and innovative preventive strategies able to induce a negative signaling are currently under evaluation. Also, using well known preventive treatments, such as allergen specific immunotherapy may offer new perspectives for the management of patients at risk of potentially fatal reaction to foods. In fact, controlled studies demonstrated that sublingual immunotherapy is able to significantly increase the tolerance to the causative foods, fulfilling the need and protecting the allergic subject from anaphylaxis caused by accidental ingestion of small food amounts. The article also presented some promising patents on anaphylaxis.

New applications for sublingual immunotherapy in allergy

Specific immunotherapy is the only treatment targeting the causes, and not only the symptoms, of allergic diseases. Sublingual immunotherapy (SLIT) was introduced and developed to solve the problem of the adverse reactions, uncommon but possibly severe and rarely fatal, to the traditional subcutaneous immunotherapy (SCIT). The evidence of SLIT efficacy concerns rhinitis and asthma caused by sensitization to pollens and to house dust mites, but there are increasing data suggesting that SLIT could be applied in forms of allergy hardly feasible for SCIT because of its poor safety (this is true for food allergy and latex allergy) or could be considered for new applications, such as atopic dermatitis or baker's asthma. In particular, there are placebo-controlled trials indicating good efficacy and safety of SLIT in patients allergic to latex and to foods and in children with atopic dermatitis, that indicate SLIT as a real treatment option in such clinical entities. This article also discusses some patent related to the field.

Effectiveness of omalizumab in a patient with severe asthma and atopic dermatitis

The anti-IgE antibody omalizumab is currently indicated in severe asthma not controlled by standard drug therapy. Recently, new indications for omalizumab were suggested, which include atopic dermatitis (AD), a skin disorder characterized by elevated levels of IgE. We report the case of a 39-year old woman with severe asthma and severe AD, both resistant to conventional drug treatment. The patient had a IgE level of 1304 kU/L, which exceeded the recommended maximum level for treating asthma with omalizumab (stated in 700 Ku/L) but was far lower than previously reported in cases of AD treated with anti-IgE. The treatment consisted of a dose of omalizumab 375 mg every two weeks, and induced a rapid improvement of asthma, with no need of other drugs after three months, along with a progressive decline of severity of AD, which after five months was completely cured. These findings suggest the usefulness of omalizumab in patients with concomitant severe asthma and AD, also considering the pharmaco-economic balance obtained by withdrawing the multiple drugs used to treat both diseases.

[Neck and upper limb disorders caused by combined exposures to ergonomic risk factors and hand-transmitted vibration]

A review of neck and upper limb disorders caused by combined exposures to hand-transmitted vibration and ergonomic risk factors (repetitiveness, force, posture) suggested the following conclusions: (1) hand-transmitted vibration has a dominant role in the etiopathogenesis of Raynaud's phenomenon and various forms of peripheral neuropathy with sensory impairment (digital, multifocal) in users of vibrating tools; (2) vibration of low frequency and high amplitude from percussive tools concur, together with adverse ergonomic factors, to produce degenerative changes in the bones and joints of the upper limbs, mainly in the wrist and elbow; (3) there is strong epidemiological and experimental evidence that combined exposures to hand-transmitted vibration and physical load are associated with an excess risk of carpal tunned syndrome; (4) there is limited evidence for an association between Dupuytren's contracture and vibration exposure owing to the small number of currently available epidemiological studies; (5) there is insufficient evidence for a contribution of hand-transmitted vibration to the development of chronic pain and clinical syndromes in the neck and upper limb, while excessive physical load and ergonomic stress have a primary role in the etiopathogenesis of these disorders.

Mandibular osteomyelitis due to Pseudomonas aeruginosa. Case report

Osteomyelitis is a relatively frequent bacterial infection of the jaw bones. This report describes a case of mandibular osteomyelitis in a surgical site after enucleation of a follicular cyst and extraction of the associated tooth. This case is unusual because maxillary osteomyelitis generally results from polymicrobial infection. In our patient, however, laboratory analysis identified Pseudomonas aeruginosa as the etiologic agent, an opportunistic pathogen normally found on moist surfaces and vegetation. Notorious for its antibiotic multiresistance, P. aeruginosa is increasingly recognized as a serious problem in hospitalized patients. Isolation of the responsible microbe permitted specific antibiotic treatment with a 10-day course of ciprofloxacin (250 mg/12 h), which fully cleared the infection.

Barriers to obesity treatment

Obesity, one of the most prevalent health problems in the Western world, is a chronic and progressive condition. Therefore, as with other chronic diseases, patients with obesity require lifelong treatment. Long-term efficacy and effectiveness of obesity treatments is notoriously poor. This may in part be attributable to the substantial barriers that undermine long-term obesity management strategies. These can include lack of recognition of obesity as a chronic condition, low socioeconomic status, time constraints, intimate saboteurs, and a wide range of comorbidities including mental health, sleep, chronic pain, musculoskeletal, cardiovascular, respiratory, digestive and endocrine disorders. Furthermore, medications used to treat some of these disorders may further undermine weight-loss efforts. Lack of specific obesity training of health professionals, attitudes and beliefs as well as coverage and availability of obesity treatments can likewise pose important barriers. Health professionals need to take care to identify, acknowledge and address these barriers where possible to increase patient success as well as compliance and adherence with treatments. Failure to do so may further undermine the sense of failure, low self esteem and self efficacy already common among obese individuals. Addressing treatment barriers can save resources and increase the prospect of long-term success.

Patient's compliance with allergen immunotherapy

BACKGROUND

Allergen immunotherapy (IT) is an effective treatment of respiratory allergy, but requires strict rules of performance. This makes compliance particularly relevant, but thus far only a few studies have investigated this issue.

METHODS

We reviewed all the available articles on compliance and adherence with IT in its different forms of administration, ie, subcutaneous (SCIT), sublingual (SLIT), and local nasal (LNIT).

RESULTS

Early studies, when only SCIT was available, reported a low compliance, ranging from 45% to 60%, but the demanding schedules used, with very frequent injections, accounted for this outcome, as shown by patients' recognition of inconvenience as the major cause of noncompliance. The most recent studies reported a good compliance, estimated in 75% to 90%, to both SCIT and SLIT, inconvenience remaining the major cause of noncompliance, followed by cost of the treatment. The only study addressing LNIT found a very poor compliance (27%), the major cause being the side effects, with repeated nasal reactions to the allergen extract.

CONCLUSIONS

Adequate education of patients and optimization of administration schedules, with fine balancing between dose effectiveness and cost, are the factors most likely to achieve further improvement of compliance with IT.

Clinical onset of celiac disease after an episode of Campylobacter jejuni enteritis

The present report describes a young woman with no previous gastrointestinal complaints who was initially diagnosed with postinfective irritable bowel syndrome (IBS) after a confirmed case of Campylobacter jejuni enteritis. However, because of persistent diarrhea, new-onset bloating and the development of iron and vitamin deficiencies, serological markers for celiac disease (CD) were evaluated. A positive tissue transglutaminase immunoglobulin A antibody test and repeat endoscopy with duodenal biopsy showing a Marsh IIIa lesion confirmed the diagnosis of CD. Infectious gastroenteritis is a well-established risk factor for the development of IBS, and there is recent evidence that it could play a role in the initiation and exacerbation of inflammatory bowel disease. The present case suggests that the clinical expression of CD can be unmasked by an acute gastrointestinal infection and supports the hypothesis that environmental factors other than gliadin may play a role in the clinical onset of CD in a genetically susceptible host. The increasing availability of serological testing and upper endoscopy has led to increasingly frequent diagnoses of CD and recognition that it may mimic IBS. The present case findings suggest that CD should be considered in the differential diagnosis of persistent IBS-like symptoms after an episode of infectious gastroenteritis.

Evaluation of densitometric bone-muscle relationships in Crohn's disease

BACKGROUND

Patients with Crohn's disease (CD) are 1.4 to 2.5 times more likely than the normal population to sustain a fracture but the factors involved in the pathogenesis are not clearly understood. Bone mass is affected both by nutrition and by muscular activity. Trauma excepted, the largest voluntary loads on bones come from muscle contraction, not body weight.

AIM

To assess the relationship between bone mass (bone mineral content) and muscle mass (lean mass) in CD patients.

METHODS

Adult CD patients who had had a whole body, lumbar and hip densitometric evaluation were selected. Information regarding age, gender, weight, duration of CD, age at diagnosis, use of glucocorticoids and disease activity during the year before densitometric evaluation and laboratory parameters were collected.

RESULTS

Data from 65 patients (28.8+/-10.6 years, F=44, M=21) were analyzed. Lumbar bone mineral content (BMC), BMC in both hips, total and regional BMC significantly correlated with body weight and total and regional lean mass (LM). In multiple regression analysis, only total LM was shown to be independently associated with lumbar BMC, BMC in both hips and total BMC. LM in upper and lower limbs was shown to be independently associated with BMC in upper and lower limbs, respectively.

CONCLUSIONS

These results suggest that muscular mass and activity, rather than overall body weight, are important determinants of bone mass and, hence of bone strength in Crohn's disease. Thus, the management of bone loss in inflammatory bowel disease should address the effects of both nutrition and exercise on muscle mass.

Juvenile onset of Crohn's disease: a risk factor for reduced lumbar bone mass in premenopausal women

BACKGROUND

Crohn's disease (CD) is associated with reduced bone mass. Bone fragility is the result of both growth-related and age-related factors; thus, exposure to a chronic illness, such as CD, during skeletal growth may compromise peak bone mass. Our aim was to assess whether the onset of CD during skeletal growth had an impact on bone mass in adulthood in premenopausal women.

METHODS

Adult premenopausal CD patients who had a whole body, lumbar and hip bone densitometric evaluation were selected. Information regarding age, gender, weight, duration of CD, age at diagnosis, use of glucocorticoids and disease activity during the year before densitometric assessment and laboratory parameters were collected.

RESULTS

Data from 57 patients (28+/-10 years) were analyzed. Age at diagnosis was independently associated with lumbar bone mineral content (BMC). Lean mass was independently associated with total, lumbar and hip BMC. Patients with a history of onset of CD before 16 years of age (n=20) were 11.6+/-2 years old at diagnosis. They had low lumbar and hip Z scores. They had significantly lower BMC, bone mineral density and Z scores in lumbar area and both hips than those diagnosed after the age of 16. They also had significantly lower lumbar area than those diagnosed after the age of 16.

CONCLUSIONS

The onset of CD during skeletal growth is a risk factor for reduced lumbar and hip bone mass in adulthood in premenopausal women.

Comparison of efficacy, safety and immunologic effects of subcutaneous and sublingual immunotherapy in birch pollinosis: a randomized study

BACKGROUND

Sublingual immunotherapy (SLIT) is currently considered a valid option to subcutaneous immunotherapy (SCIT), but only a few studies made a direct comparison of their effectiveness. The aim of this study was to compare the clinical and immunological effects of SCIT and SLIT in pollinosis induced by Betulaceae.

METHODS

Forty-seven adult patients were randomized to receive SCIT or SLIT, performed by Betulaceae (alder, birch, and hazel) extracts from Stallergenes (Antony, France) standardized in index of reactivity (IR) with the treatment schedules proposed by the producer. The clinical effects were established by symptom-medication scores recorded during the month of March. Side effects were reported directly by the physicians for SCIT and were registered in diary cards by the patients for SLIT. Immunologic evaluation was done by measuring specific IgE and IgG4 to Bet v 1.

RESULTS

Thirty-four patients (19 for SCIT and 15 for SLIT) completed the registration of symptoms and drug consumption during pollen period of Betulaceae. Mean cumulative doses of respectively 50.65 IR by SCIT and 4653.1 IR by SLIT were administered, with a SLIT/SCIT ratio of 92. There was no significant difference in mean symptom-medication score between SCIT and SLIT. Systemic reactions occurred in 16% of SCIT treated but in none of SLIT treated. As to immunologic evaluation, Bet v 1 specific IgE did not rise after the pollen season in SCIT treated, while increased non significantly in SLIT treated. Bet v 1 specific IgG4 increased in both treatment, buy only the increase with SCIT was significant (p = 0.001).

CONCLUSION

SLIT and SCIT with a ratio of about 100 are equally effective in controlling rhinoconjunctivitis caused by tree pollen allergy. SLIT is safer than SCIT, but does not show the same immunologic effects on serum specific IgE and lgG4 antibodies.

13C urea breath test for (Helicobacter pylori): determination of the optimal cut-off point in a Canadian community population

AIM

To determine the test characteristics and the optimal cut-off point for the (13)C urea breath test ((13)C UBT) in a Canadian community laboratory setting.

METHODS

Of 2232 patients (mean age +/- SD: 51+/-21 years, 56% female) who completed a (13)C UBT, 1209 were tested to evaluate the primary diagnosis of (Helicobacter pylori) infection and 1023 were tested for confirmation of eradication following treatment. Cluster analysis was performed on the (13)C UBT data to determine the optimal cut-off point and the risk of false-positive and false-negative results. Additionally, 176 patients underwent endoscopic biopsy to allow validation of the sensitivity and specificity of the (13)C UBT against histology and microbiology using the calculated cut-off point.

RESULTS

The calculated cut-off points were 3.09 delta/1000 for the whole study population (n=2232), 3.09 delta/1000 for the diagnosis group (n=1209) and 2.88 delta/1000 for the post-treatment group (n=1023). When replacing the calculated cut-off points by a practical cut-off point of 3.0 delta/1000, the risk of false-positive and false-negative results was lower than 2.3%. The (13)C UBT showed 100% sensitivity and 98.5% specificity compared with histology and microbiology (n=176) for the diagnosis of active (H pylori) infection.

CONCLUSIONS

The (13)C UBT is an accurate, noninvasive test for the diagnosis of (H pylori) infection and for confirmation of cure after eradication therapy. The present study confirms the validity of a cut-off point of 3.0 delta/1000 for the (13)C UBT when used in a large Canadian community population according to a standard protocol.

13C urea breath test for (Helicobacter pylori): evaluation of 10-minute breath collection

AIM

To determine whether a shortened (13)C urea breath test ((13)C UBT) (breath collection time of 10 min) is as reliable as the standard assay (30 min).

METHODS

Two hundred ninety-seven patients (mean +/- SD: 53+/-16 years, 57% female) completed a (13)C UBT. Breath samples were obtained at baseline and at 5 min intervals up to 30 min. Sixty-seven patients also underwent endoscopic biopsy. Cluster analysis was performed on the (13)C UBT data to determine the optimal cut-off point at each time interval. Sensitivity and specificity of the (13)C UBT at all intervals compared with histology and culture and against the standard 30 min interval were determined.

RESULTS

The calculated optimal cut-off points for each time interval (T), expressed as delta over baseline (delta/1000), were 3.29 delta/1000 at T(5), 3.15 delta/1000 at T(10), 3.42 delta/1000 at T(15), 3.17 delta/1000 at T(20), 2.99 delta/1000 at T(25) and 2.82 delta/1000 at T(30). Except at T(5), the risk of false-positive and false-negative test results at each time interval was lower than 2.3% using these cut-off points. When replacing the cut-off points with 3.0 delta/1000, the risk of error was still lower than 2.3%. The test at T(10) showed 98.6% sensitivity and 98.6% specificity compared with T(30). T(10) and T(30) showed 100% sensitivity and 96% specificity compared with histology and culture.

CONCLUSIONS

The (13)C UBT is an accurate, noninvasive test, even when the breath sample interval is reduced to 10 min. The present study confirms the validity of a cut-off point of 3.0 delta/1000 for the 10 min and 30 min (13)C UBT.

Mutations of the BCR-ABL-kinase domain occur in a minority of patients with stable complete cytogenetic response to imatinib

Residual leukemia is demonstrable by reverse transcriptase-polymerase chain reaction in most patients with chronic myeloid leukemia who obtain a complete cytogenetic response (CCR) to imatinib. In patients who relapse during imatinib therapy, a high rate of mutations in the kinase domain of BCR-ABL have been identified, but the mechanisms underlying disease persistence in patients with a CCR are poorly characterized. To test whether kinase domain mutations are a common mechanism of disease persistence, we studied patients in stable CCR. Mutations were demonstrated in eight of 42 (19%) patients with successful amplification and sequencing of BCR-ABL. Mutation types were those commonly associated with acquired drug resistance. Four patients with mutations had a concomitant rise of BCR-ABL transcript levels, two of whom subsequently relapsed; the remaining four did not have an increase in transcript levels and follow-up samples, when amplifiable, were wild type. BCR-ABL-kinase domain mutations in patients with a stable CCR are infrequent, and their detection does not consistently predict relapse. Alternative mechanisms must be responsible for disease persistence in the majority of patients.