Terry Chin

Resolution of corticosteroid-induced diabetes in allergic bronchopulmonary aspergillosis with omalizumab therapy: a novel approach.

Allergic bronchopulmonary aspergillosis (ABPA) occurs in up to 15% of patients with cystic fibrosis (CF) (1). Clinically, the disease manifests by symptoms consistent with bronchial asthma along with wheezing, pulmonary infiltrates, and bronchiectasis. Variable immunologic responses to Aspergillus fumigatus antigens are observed including peripheral blood eosinophilia, prick skin test reactivity, increased levels of total serum immunoglobulin (IgE), the presence of precipitating antibodies and increased specific serum IgE and IgG antibodies to A fumigatus (2,3). Treatment of ABPA targets the inflammatory and immunological activity with corticosteroids in concert with an overall reduction of airway fungal load with antifungal agents (4). Long-term treatment is often required because of repeated exacerbations when corticosteroid treatment is tapered. Owing to chronic systemic corticosteroid use, serious adverse events frequently include insulin resistance, hyperglycemia, and chronic diabetes (5). Allergic bronchopulmonary aspergillosis frequently results in severe worsening of the respiratory condition in patients with chronic obstructive lung disease, particularly cystic fibrosis. Treatment can result in steroid dependency and serious adverse events (6). Several case reports of improvement of respiratory symptoms and lung function after treatment with anti-IgE antibody (omalizumab) in cystic fibrosis patients with ABPA have been described (7,8). While previous benefits of omalizumab have been noted in ABPA, this report focuses on the subgroup of CF patients with steroid-induced hyperglycemia. As systemic corticosteroids are a mainstay of therapy in ABPA, this subgroup requires intensive glucose monitoring while on steroids. We report a case of corticosteroid-induced diabetes in a patient with CF and ABPA subsequently treated with omalizumab.

Clinical significance of respiratory isolates for Mycobacterium abscessus complex from pediatric patients

Mycobacterium abscessus complex is the most virulent of rapidly growing mycobacteria causing invasive lung disease. To better delineate clinical pediatric experience and outcomes with M. abscessus complex, we retrospectively gathered 5‐year data on M. abscessus complex infection and outcomes in a large, hospital‐based pediatric pulmonary center. Patients were selected from the database of the microbiology department at Miller Childrens Hospital in Long Beach, CA. Patients had at least one positive pulmonary isolate for M. abscessus complex from February 2006 to May 2011. Treatment modality data were collected and successful therapy of disease was determined as clearance of M. abscessus complex infection after antibiotics proven by culture negative respiratory isolate within at least 12 months of therapy initiation. Two cystic fibrosis patients with M. abscessus complex were identified, one with failed therapy and the other with stable pulmonary status despite persistent isolation. One primary ciliary dyskinesia patient had successful clearance of M. abscessus complex, however is now growing M. avium intracellulare. A patient with no prior medical history was successfully treated with antimycobacterial therapy. Eleven patients with neuromuscular disorders had tracheal aspirates positive for M. abscessus complex. None were treated due to stable lung status and all but two had spontaneous clearance of the mycobacteria. The two remaining persist with sporadic isolation of M. abscessus complex without clinical significance. We concluded that patients with tracheostomy associated M. abscessus complex infections do not appear to require treatment and often have spontaneous resolution. Cystic fibrosis or primary ciliary dyskinesia patients may have clinical disease warranting treatment, but current antimycobacterial therapy has not proven to be completely successful. As M. abscessus complex gains prevalence, standardized guidelines for diagnosis and therapy are needed in the pediatric population. Multicenter cohort analysis is necessary to achieve such guidelines. Pediatr Pulmonol. 2013; 48:470–480.

Wiskott-Aldrich Syndrome: Description of a New Gene Mutation With Normal Platelet Volume.

Wiskott-Aldrich syndrome (WAS) is a rare X-linked primary immunodeficiency characterized by an increased incidence of autoimmunity, malignancy, microthrombocytes with thrombocytopenia, eczema, and recurrent infections. In this case report, we present a novel mutation, hemizygous for c.1125_1129delTGGAC mutation in the WAS gene, and a unique clinical presentation. Our patient was initially diagnosed with a milk protein allergy after presenting with a lower gastrointestinal bleed, leukopenia, and thrombocytopenia with normal platelet volume. However, signs of vasculitis and detection of microthrombocytes required additional testing and consideration of WAS. This case report illustrates the importance of retaining a high index of clinical suspicion despite normal platelet volume, as well as adding to the growing number of known mutations associated with WAS.

Vigorous Exercise Can Cause Abnormal Pulmonary Function in Healthy Adolescents

RATIONALE Although exercise-induced bronchoconstriction is more common in adolescents with asthma, it also manifests in healthy individuals without asthma. The steady-state exercise protocol is widely used and recommended by the American Thoracic Society (ATS) as a method to diagnose exercise-induced bronchoconstriction. Airway narrowing in response to exercise is thought to be related to airway wall dehydration secondary to hyperventilation. More rigorous exercise protocols may have a role in detecting exercise-induced bronchoconstriction in those who otherwise have a normal response to steady-state exercise challenge. OBJECTIVES The objective of this study was to determine the effect of two different exercise protocols--a constant work rate protocol and a progressive ramp protocol--on pulmonary function testing in healthy adolescents. We hypothesized that vigorous exercise protocols would lead to reductions in lung function in healthy adolescents. METHODS A total of 56 healthy adolescents (mean age, 15.2 ± 3.3 [SD] years) were recruited to perform two exercise protocols: constant work rate exercise test to evaluate for exercise-induced bronchoconstriction (as defined by ATS) and standardized progressive ramp protocol. Pulmonary function abnormalities were defined as a decline from baseline in FEV1 of greater than 10%. MEASUREMENTS AND MAIN RESULTS Ten participants (17.8%) had a significant drop in FEV1. Among those with abnormal lung function after exercise, three (30%) were after the ATS test only, five (50%) were after the ramp test only, and two (20%) were after both ATS and ramp tests. CONCLUSION Healthy adolescents demonstrate subtle bronchoconstriction after exercise. This exercise-induced bronchoconstriction may be detected in healthy adolescents via constant work rate or the progressive ramp protocol. In a clinical setting, ramp testing warrants consideration in adolescents suspected of having exercise-induced bronchoconstriction and who have normal responses to steady-state exercise testing.