Faculty

Michael E. Wechsler, M.D.

Specialty: Pulmonary Medicine

Brigham and Women’s Hospital

Clinics 3
15 Francis Street
Boston, MA 02115

Publications

The following is a list of recent publications for which this Partners Asthma Center physician has been cited as an author in PubMed databases. Study abstracts have been provided for your convenience.

van's Gravesande, K. S., M. E. Wechsler, et al. (2003). "Association of a missense mutation in the NOS3 gene with exhaled nitric oxide levels." Am J Respir Crit Care Med 168(2): 228-31.

There is evidence that genetic factors affect nitric oxide formation and that sequence variants in the nitric oxide synthase genes contribute to the observed variance of nitric oxide levels in exhaled air (fraction of expired nitric oxide, FENO) in subjects with asthma. We identified a strong association between a known functional NOS3 missense sequence variant in the endothelial nitric oxide gene (G894T) and FENO level in a cohort of subjects with asthma. Age- and sex-adjusted FENO levels were lowest in asthmatic subjects with the TT genotype (geometric mean FENO [95% CI] = 7.17 [4.48 to 11.48] ppb) and were significantly higher in those with either the GT genotype (geometric mean FENO [95% CI] = 17.11 [13.80 to 21.23] ppb) or the GG genotype (geometric mean FENO [95% CI] = 12.06 [9.91 to 14.67] ppb) (F2,59 = 5.97, p = 0.004). The G894T DNA variant explained 16.3% of the residual variance in FENO levels. Our results demonstrate that the endothelial nitric oxide synthase, a nitric oxide synthase constitutively expressed in epithelial cells, plays an important role in determining measured levels of exhaled nitric oxide, a marker of the asthmatic condition.

Kalayci, O., M. Wechsler, et al. (2003). "LTC4 production by eosinophils in asthmatic subjects with alternative forms of ALOX-5 core promoter." Adv Exp Med Biol 525: 11-4.

Wechsler, M. E. and E. Israel (2002). "Pharmacogenetics of treatment with leukotriene modifiers." Curr Opin Allergy Clin Immunol 2(5): 395-401.

PURPOSE OF REVIEW Pharmacogenetics is emerging as a field with great potential to improve both our understanding and treatment options in asthma. This review highlights the importance of pharmacogenetic associations of an important class of asthma therapy, the leukotriene modifiers, and asthma. RECENT FINDINGS: Over the past decade, different leukotriene modifier therapies have emerged and have resulted in improvements in asthma parameters in individuals with this condition. However, there is substantial interindividual variability with respect to the response to this and other asthma therapies. Over the past few years, polymorphisms of two genes in the leukotriene pathway, the gene and the synthase gene, have been identified and have been demonstrated to have pharmacogenetic associations with asthma. However, currently identified genetic determinants explain the response to therapy in only a minority of patients. SUMMARY: As the field of pharmacogenetics advances, an increasing proportion of individual variation in response to pharmacotherapy will be predictable on the basis of associations with particular genetic polymorphisms or patterns of polymorphisms. The pharmacogenetic association of leukotriene modifiers and asthma is an excellent example of how these associations hold out the promise of being able to individualize pharmacotherapy, by providing specific medications to those most likely to respond while avoiding therapy in those most likely to suffer adverse effects.

Lilly, C. M., A. Churg, et al. (2002). "Asthma therapies and Churg-Strauss syndrome." J Allergy Clin Immunol 109(1): S1-19.

The pulmonary vasculitides are a group of rare but serious disorders that require early recognition, accurate diagnosis, and effective therapy. Churg-Strauss syndrome (CSS) is classified as small vessel vasculitis. Four different definitions for the diagnosis of CSS have been developed: (1) the pathologic criteria put forth by Churg and Strauss, (2) the criteria based on clinical grounds from Lanham and colleagues, (3) the criteria based on clinical grounds from the American College of Rheumatology, and (4) the criteria from the Chapel Hill Consensus Conference, which closely concur with the Churg and Strauss definition. It is apparent that cessation, diminution, or even a switch from low-dose systemic to inhaled corticosteroid therapy can precipitate the appearance of CSS. The term forme fruste has been used to indicate that the signs and symptoms of CSS were (inadvertently) suppressed by cortico-steroids. The clinical risk factors for CSS are moderately severe or severe asthma, chronic sinusitis, or reductions in systemic corticosteroid therapy. Differential diagnosis, treatment, and ongoing monitoring of CSS therapeutic responses are reviewed. The introduction of leukotriene modifiers and high-potency inhaled corticosteroids have allowed control of asthma symptoms, which results in avoidance or reduction in oral corticosteroid use. The advent of these agents has been associated with reports of CSS appearing in patients with asthma. The available data regarding the association of CSS and antiasthma agents are most consistent with the unmasking of a previously contained pathologic condition (forme-fruste CSS) or disease that progresses because systemic corticosteroids were avoided. Early recognition and immunosuppressive therapy are the keystones of successful treatment of this rare disorder.

Wechsler, M. E., D. Finn, et al. (2000). "Churg-Strauss syndrome in patients receiving montelukast as treatment for asthma." Chest 117(3): 708-13.

STUDY OBJECTIVES: We previously reported eight patients who developed Churg-Strauss syndrome in association with zafirlukast treatment for asthma and postulated that the syndrome resulted from unmasking of a previously existing condition due to corticosteroid withdrawal and not from a direct drug effect. The availability of montelukast, a new leukotriene receptor antagonist with a different molecular structure, permitted us to test this hypothesis. Our goals were to ascertain whether the Churg-Strauss syndrome developed in patients taking montelukast and other novel asthma medications, and to describe potential mechanisms for the syndrome. DESIGN: Case series. SETTING: Outpatient and hospital practices of pulmonologists in the United States and Belgium. PATIENTS: Four adults (one man, three women) who received montelukast as treatment for asthma; two women who received salmeterol/fluticasone therapy, but not montelukast. RESULTS: Churg-Strauss syndrome developed in the four asthmatic patients who received montelukast. In each case, there was a long history of difficult-to-control asthma characterized by multiple exacerbations that had required frequent courses of oral systemic corticosteroids or high doses of inhaled corticosteroids for control. Two other asthmatics who received fluticasone and salmeterol but not montelukast therapy developed the same syndrome with tapering doses of oral or high doses of inhaled corticosteroids. CONCLUSIONS: The occurrence of Churg-Strauss syndrome in asthmatic patients receiving leukotriene modifiers appears to be related to unmasking of an underlying vasculitic syndrome that is initially clinically recognized as moderate to severe asthma and treated with corticosteroids. Montelukast does not appear to directly cause the syndrome in these patients.

Wechsler, M. E., H. Grasemann, et al. (2000). "Exhaled nitric oxide in patients with asthma: association with NOS1 genotype." Am J Respir Crit Care Med 162(6): 2043-7.

An increased concentration of nitric oxide (NO) in exhaled air (FENO) is now recognized as a critical component of the asthmatic phenotype. When we identified patients with asthma on the basis of a standard case definition alone, we found that they were remarkably heterogeneous with respect to their FENO. However, when we included genotype at a prominent asthma candidate gene (i.e., NOS1) in the case definition, and determined the number of AAT repeats in intron 20, we identified a remarkably homogeneous cohort of patients with respect to FENO. Both mean FENO (p = 0.00008) and variability around the mean (p = 0.000002) were significantly lower in asthmatic individuals with a high number (> or = 12) of AAT repeats at this locus than in those with fewer repeats. These data provide a biologically tenable link between genotype at a candidate gene in a region of linkage, NOS1, and an important component of the asthmatic phenotype, FENO. We show that addition of NOS1 genotype to the case definition of asthma allows the identification of a uniform cohort of patients, with respect to FENO, that would have been indistinguishable by other physiologic criteria. Our isolation of this homogeneous cohort of patients ties together the well-established associations among asthma, increased concentrations of NO in the exhaled air of asthmatic individuals, and variations of trinucleotide repeat sequences as identified in several neurologic conditions.

Dellaripa, P. F., M. E. Wechsler, et al. (2000). "Recurrent panniculitis in a man with asthma receiving treatment with leukotriene-modifying agents." Mayo Clin Proc 75(6): 643-5.

Leukotriene-modifying drugs are novel agents introduced recently to treat asthma. Both 5-lipoxygenase inhibitors, such as zileuton, and leukotriene receptor antagonists, such as zafirlukast and montelukast, have proved effective in the treatment of asthma. To our knowledge, there have been no detailed reports regarding dermatologic manifestations of this class of drugs. This article describes an unusual case of erythema nodosum in a 46-year-old asthmatic man who received 2 different leukotriene modifiers.

Wechsler, M. and J. M. Drazen (1999). "Churg-Strauss syndrome." Lancet 353(9168): 1970-1.

Wechsler, M. E. and J. M. Drazen (1999). "Zafirlukast and Churg-Strauss syndrome." Chest 116(1): 266-7.

Wechsler, M. E., R. Pauwels, et al. (1999). "Leukotriene modifiers and Churg-Strauss syndrome: adverse effect or response to corticosteroid withdrawal?" Drug Saf 21(4): 241-51.

Zafirlukast, montelukast and pranlukast are all cysteinyl leukotriene receptor antagonists that have recently been approved for the treatment of asthma. Within 6 months of zafirlukast being made available on the market, 8 patients who received the agent for moderate to severe asthma developed eosinophilia, pulmonary infiltrates, cardiomyopathy and other signs of vasculitis; the syndrome that these patients developed was characteristic of the Churg-Strauss syndrome. All of the patients had discontinued systemic corticosteroid use within 3 months of presentation and all developed the syndrome within 4 months of zafirlukast initiation. The syndrome dramatically improved in each patient upon reinitiation of corticosteroid therapy. Since the initial report, there have been multiple similar cases reported to the relevant pharmaceutical companies and to federal drug regulatory agencies in association with zafirlukast as well as with pranlukast, montelukast, and with use of high doses of inhaled corticosteroids, thus leading to an increased incidence rate of the Churg-Strauss syndrome. Many potential mechanisms for the association between these drugs and the Churg-Strauss syndrome have been postulated including: increased syndrome reporting due to bias; potential for allergic drug reaction; and leukotriene imbalance resulting from leukotriene receptor blockade. However, careful analysis of all reported cases suggests that the Churg-Strauss syndrome develops primarily in those patients taking these asthma medications who had an underlying eosinophilic disorder that was being masked by corticosteroid treatment and unmasked by novel asthma medication-mediated corticosteroid withdrawal, similar to the forme fruste of the Churg-Strauss syndrome. It remains unclear what the exact mechanism for this syndrome is and whether this represents an absolute increase in cases of vasculitis, but it appears that none of the asthma medications implicated in leading to the development of Churg-Strauss syndrome was directly causative of the syndrome. These agents remain well tolerated and effective medications for the treatment of asthma, although physicians must be wary for the signs and symptoms of the Churg-Strauss syndrome, particularly in patients with moderate to severe asthma in whom corticosteroids are tapered.

Kitua, A. Y., H. Urassa, et al. (1999). "Antibodies against Plasmodium falciparum vaccine candidates in infants in an area of intense and perennial transmission: relationships with clinical malaria and with entomological inoculation rates." Parasite Immunol 21(6): 307-17.

Serum immunoglobulin (Ig)G1, IgG3 and total IgG were assessed by immunoabsorbent assay in 198 infants from a Tanzanian village highly endemic for Plasmodium falciparum. Antibodies were measured against epitopes of the circumsporozoite protein (the repetitive epitope (NANP)50 and a construct of the flanking regions (CS27IC)), the malaria vaccine SPf66, and two constructs of the merozoite surface protein-1 (MSP-1), a 19-kDa fragment from the C-terminal domain (MSP-119) and an N-terminal fragment spanning blocks 1-6 (H6-p190 M-1/6-H6). IgG1 and total IgG titres showed similar age profiles, all decreasing for the first 2 months of life. Anti-(NANP)50 titres remained very low throughout the first year of life, while anti-CS27IC antibody appeared to peak around 7 months of age. Only a slight tendency to increase with age was observed for levels of the other antibodies studied. IgG3 titres except for H6-p190(1/6), were very low initially and remained very low throughout the first year of life. Clinical malaria incidence at the village dispensary was analysed prospectively in relation to antibody. No IgG1 or total IgG titre showed protective effects, but low IgG3 against p190(1/6) appeared to be a risk factor in some age groups. Given the large number of antibodies tested, this single indication of possible protection could merely be chance. There were no strong associations between antibody titres and entomologically assessed sporozoite exposure suggesting that transmission-reducing interventions may have little effect on antibody levels in such children.

Hein, K. D., M. E. Wechsler, et al. (1999). "The adult respiratory distress syndrome after dextran infusion as an antithrombotic agent in free TRAM flap breast reconstruction." Plast Reconstr Surg 103(6): 1706-8.

Adult respiratory distress syndrome occurred in a patient who had received dextran as a routine antithrombotic agent during and after free TRAM breast reconstruction. Although most patients who receive dextran have no adverse reaction, particularly after hapten inhibition by dextran 1 infusion, the serious nature of this complication in an elective operation calls into question the continuing routine use of dextran in microsurgery.

Wechsler, M. E., E. Garpestad, et al. (1998). "Pulmonary infiltrates, eosinophilia, and cardiomyopathy following corticosteroid withdrawal in patients with asthma receiving zafirlukast." Jama 279(6): 455-7.

CONTEXT: Zafirlukast is a potent leukotriene antagonist that recently was approved for the treatment of asthma. As use of this drug increases, adverse events that occur at low frequency or in populations not studied in premarketing clinical trials may become evident. OBJECTIVE: To describe a clinical syndrome associated with zafirlukast therapy. DESIGN: Case series. PATIENTS: Eight adults (7 women and 1 man) with steroid-dependent asthma who received zafirlukast. MAIN OUTCOME MEASURES: Development of a clinical syndrome characterized by pulmonary infiltrates, cardiomyopathy, and eosinophilia following the withdrawal of corticosteroid treatment. RESULTS: The clinical syndrome developed while patients were receiving zafirlukast from 3 days to 4 months and from 3 days to 3 months after corticosteroid withdrawal. All 8 patients developed leukocytosis (range, 14.5-27.6 x 10(9)/L) with eosinophilia (range, 0.19-0.71). Six patients had fever (temperature >38.5 degrees C), 7 had muscle pain, 6 had sinusitis, and 6 had biopsy evidence of eosinophilic tissue infiltration. The clinical syndrome improved with discontinuation of zafirlukast treatment and reinitiation of corticosteroid treatment or addition of cyclophosphamide treatment. COMMENT: Development of pulmonary infiltrates, cardiomyopathy, and eosinophilia may have occurred independent of zafirlukast use or may have resulted from an allergic response to this medication. We suspect that these patients may have had a primary eosinophilic infiltrative disorder that had been clinically recognized as asthma, was quelled by steroid treatment, and was unmasked following corticosteroid withdrawal facilitated by zafirlukast.

Meister, G. and M. Wechsler (1998). "Biodegradation of N-methylmorpholine-N-oxide." Biodegradation 9(2): 91-102.

N-Methylmorpholine-N-oxide (NMMO) is capable of dissolving cellulose without any further addition of chemicals. The solution can be used to produce cellulosic staple fibres by pressing it through spinning jets into an aqueous spinning bath. Because of results from conventional biodegradation tests using non-adapted activated sludge, the solvent is generally considered being persistent. The object of the described work was to show, whether and how activated sludge can be adapted to N-methylmorpholine-N-oxide and whether it is possible to purify NMMO-containing wastewaters in conventional wastewater treatment plants. The experiments showed that the sludge can be adapted within about 15-20 days. Adapted sludge can degrade the substance itself and its most important metabolites to concentrations below their detection levels and retain this ability even during limited periods without solvent being present in the wastewater. The main requirement for a successful adaptation is a high sludge age. The degradation takes place in several steps. First, NMMO is reduced to N-methylmorpholine. The next step is a demethylation of N-methylmorpholine to morpholine. This step is crucial for the adaptation process. Once morpholine has been formed, the adaptation proceeds very quickly until none of the substances in question can be detected any longer. So the next step must be the cleavage of the morpholine ring structure.