Improving Detection of Alpha-1 Antitrypsin Deficiency: Role of the Allergist

Alpha-1 antitrypsin deficiency (AATD) is a genetic disorder that manifests as lung and/or liver disease. Because symptoms of AATD overlap with those of common pulmonary and hepatic conditions, AATD is often misdiagnosed, which has resulted in substantial underdiagnosis of AATD worldwide. Although screening patients for AATD is recommended, the lack of procedures to facilitate testing remains a barrier to accurate diagnosis of AATD. Delays in AATD diagnosis can worsen outcomes for patients by postponing appropriate disease-modifying treatments. Patients with AATD-related lung disease experience symptoms similar to other obstructive lung disorders and are often misdiagnosed for years. In addition to existing screening guidelines, we recommend that screening for AATD become a standard part of allergists' workups of patients with asthma and fixed obstructive disease, chronic obstructive pulmonary disease, bronchiectasis without known origin, and patients under consideration for treatment with biologics. This Rostrum article reviews screening and diagnostic tests available in the United States and emphasizes evidence-based strategies to increase testing frequency and improve AATD detection rates. We underscore the pivotal role of allergists in managing care for patients with AATD. Finally, we urge health care providers to be aware of potentially poor clinical outcomes among patients with AATD during the coronavirus disease 2019 pandemic.

Optimization of care for patients with hereditary angioedema living in rural areas

OBJECTIVE

People living in rural areas of the United States experience greater health inequality than individuals residing in urban or suburban locations and encounter several barriers to obtaining optimal health care. Health disparities are compounded for patients with rare diseases such as hereditary angioedema (HAE), an autosomal dominant genetic disorder characterized by recurrent, severe abdominal pain and lifethreatening oropharyngeal/laryngeal swelling. The objective of this review is to explore the challenges of managing HAE patients in rural areas and suggest possible improvements for optimizing care.

DATA SOURCES

PubMed was searched for articles on patient care management, treatment challenges, rural health, and HAE.

STUDY SELECTIONS

Relevant articles were selected and reviewed.

RESULTS

Challenges in managing HAE in the rural setting were identified including obtaining a diagnosis of HAE, easy access to a physician with expertise in HAE, continuity of care, availability of telemedicine services, access to approved HAE therapies, patient education, and economic barriers to treatment. Ways to improve HAE patient care in rural areas include health care provider recognition of the undiagnosed HAE patient, development of individualized management plans, expansion of telemedicine, effective care at the local level, appropriate access to HAE medication, and increased awareness of patient support and advocacy groups.

CONCLUSION

For HAE patients living in rural areas, optimal care is complicated by health disparities. Given the scarcity with which these topics have been covered in the literature to date, it is intended that this article will serve as the impetus for a range of further initiatives focused on improving access to care.

Health-care resource utilization associated with peanut allergy management under allergen avoidance among commercially insured individuals

Background: Until recently, the standard approach to care for individuals with peanut allergy (PA) was limited to allergen avoidance and treatment of reactions with emergency medicines. Objectives: To assess health-care resource utilization (HRU) and costs associated with PA management under allergen avoidance and to identify risk factors associated with peanut reactions that resulted in inpatient (IP) and/or emergency department (ED) visits. Methods: Privately insured individuals with PA diagnosis codes were identified from a large U.S. administrative claims data base (January 1, 1999, to March 31, 2017). PA-related HRU, indicated by a PA diagnosis and/or diagnostic procedure codes and by epinephrine autoinjectors (EAI) prescription fills in medical and pharmacy claims, respectively, and all-cause costs were described per patient-year (PPY). Risk factors associated with peanut reactions in an IP and/or ED setting were identified by using a multivariable logistic regression model. Results: A total of 86,483 patient-years from 14,136 individuals with PA were included. At the patient-year level, 28.1% were ages 0-3 years, 43.6% were ages 4-11 years, 13.7% were ages 12-17 years, and 14.5% were ages ≥ 18 years; 35.6% had PA-related outpatient visits; 50.6% had EAI fills; and 2.4% had PA-related IP and/or ED visits PPY. Younger individuals had more PA-related outpatient visits and EAI fills, with peak intensive use at ages 4-11 years. The proportion of individuals with PA-related IP and/or ED visits was highest among those aged ≥ 18 years. Mean all-cause costs were $3084 PPY; individuals with PA-related IP and/or ED visits incurred $8902 PPY ($17,451 for those with one or more IP visits). Risk factors associated with peanut reactions that resulted in IP and/or ED visits included young adults (odds ratio [OR] 3.19 [95% confidence interval {CI}, 2.66-3.83]), previous peanut reaction(s) (OR 1.66 [95% CI, 1.23-2.24]), asthma (OR 1.33 [95% CI, 1.18-1.51]), and male sex (OR 1.14 [95% CI, 1.01-1.28]). Conclusion: Individuals with PA and under allergen avoidance had significant HRU that varied across all age groups, with more PA-related outpatient visits during preschool and/or school age and PA-related urgent care among adults. Individuals with previous peanut reaction(s), asthma, and males had a higher risk of peanut reactions that resulted in IP and/or ED visits.

Economic burden of peanut allergy in pediatric patients with evidence of reactions to peanuts in the United States

BACKGROUND: The economic burden of food allergy is large; however, costs specific to individuals with peanut allergy experiencing reactions to peanuts remain to be evaluated. As the prevalence of peanut allergy continues to increase in children, a better understanding of the cost of care is warranted. OBJECTIVE: To assess the cost of care of peanut allergy among privately insured and Medicaid-insured pediatric patients in the United States. METHODS: This retrospective matched-cohort study included patients aged 4-17 years from the Optum Health Care Solutions and Medicaid Claims databases (January 1, 2007-March 31, 2017). Patients were classified into 2 cohorts: peanut allergy (with peanut allergy diagnosis codes and reactions triggering health care resource utilization [HRU]) and peanut allergy-free (no peanut allergy diagnosis codes in claims). Peanut allergy patients were matched 1:10 to peanut allergy-free patients based on baseline covariates. Comorbidities including anxiety and depression, HRU, and direct health care costs were compared between cohorts and reported for both perspectives separately. RESULTS: Compared with peanut allergy-free patients (n = 30,840 privately insured; n = 12,450 Medicaid), peanut allergy patients (n = 3,084 privately insured; n = 1,245 Medicaid) had higher prevalence of asthma, atopic dermatitis/eczema, other food allergies, allergic rhinitis, depression, and anxiety (all P < 0.01). Peanut allergy patients had higher HRU per patient per year (PPPY), including 90% more emergency department visits among both privately insured and Medicaid patients (P < 0.01) and higher direct health care costs PPPY, with incremental costs of $2,247 total or $1,712 excluding asthma-related costs for privately insured patients and $2,845 total or $1,844 excluding asthma-related costs for Medicaid patients (all P < 0.01). CONCLUSIONS: Pediatric patients in the United States with peanut allergy and reactions triggering HRU had significantly higher comorbidity burdens, HRU, and direct health care costs, regardless of asthma-related costs, versus those without peanut allergy. DISCLOSURES: This study was funded by Aimmune Therapeutics, a Nestlé Health Science company. The study sponsor was involved in several aspects of the research including the study design, the interpretation of data, the writing of the manuscript, and the decision to submit the manuscript for publication. Yu and Tilles are employees of Aimmune Therapeutics, a Nestlé Health Science company. Robison and Norrett were employees of Aimmune Therapeutics at the time this study was conducted. Blaiss, Meadows, and Hass provided paid consulting services to Aimmune Therapeutics. Guerin and Latremouille-Viau are employees of Analysis Group, a consulting company that provided paid consulting services to Aimmune Therapeutics. Parts of the results were presented at the AMCP Managed Care & Specialty Pharmacy Annual Meeting held March 25-28, 2019, in San Diego, CA, and at the ISPOR Annual Meeting held May 18-22, 2019, in New Orleans, LA.

Guiding Principles for the Recognition, Diagnosis, and Management of Infants with Anaphylaxis: An Expert Panel Consensus

Infant anaphylaxis is an emerging risk, with food allergy the most common cause. Although the presentation of anaphylaxis involves the same systems as in older children and adults, there are real-world challenges to identifying symptoms of an allergic emergency in nonverbal children, as well as implementing optimal treatment. Recognition of anaphylaxis in infants can be challenging because allergic symptoms and certain normal infant behaviors may overlap. Intramuscular epinephrine is the treatment of choice for infants, as it is for older children and adults, and an epinephrine autoinjector approved by the Food and Drug Administration is now available for infants weighing between 7.5 and 15 kg. A panel of experts sought to develop guiding principles for the recognition, diagnosis, and management of anaphylaxis in infants, and provide a framework for the development of new guidelines and future research. Accordingly, anaphylaxis emergency action planning for infants was addressed by the panel. In considering formation of future infant anaphylaxis guidelines, health care providers should be aware of the needs to improve the recognition, diagnosis, and management of infants with anaphylaxis. Future research should identify and validate clinical criteria for the diagnosis of anaphylaxis in infants, as well as risk factors for the most severe reactions.

Outcome of respiratory failure in hematologic malignancy

We reviewed records of patients with hematologic malignancy requiring mechanical ventilation (MV) from 1976 to 1985 (excluding postoperative MV less than 48 hours). There were 119 episodes in 116 patients. In-hospital mortality was 82 percent. Of 21 (18 percent) episodes survived, median duration of survival was 12 months. Survivors did not differ from nonsurvivors in age, leukocyte count, or duration of MV. Survival for chronic lymphocytic leukemia was 42 percent, for other leukemias 16 percent, Hodgkin's disease 29 percent, and non-Hodgkin's lymphomas, 6 percent. Bronchoscopy was performed in 28 patients, resulting in a diagnosis of infection, hemorrhage, or malignancy in 19 cases. Open lung biopsy (OLB) was obtained in 23 patients, yielding a diagnosis of interstitial inflammation or fibrosis (13 cases), drug effect (three), malignancy (two), hemorrhage (one), Pneumocystis (seven), aspergillosis (two), and Legionella (one). Only two patients survived following OLB. Despite intensive management and adequate diagnosis, respiratory failure in patients with hematologic malignancy carries a high mortality. Although these data may help identify groups with a limited prognosis for long-term recovery, patient care must be individualized.

Clinical outcome of respiratory failure in patients requiring prolonged (greater than 24 hours) mechanical ventilation

Patients requiring prolonged (greater than 24 hours) mechanical ventilation have various conditions that result in respiratory failure. All patients requiring prolonged mechanical ventilation were subdivided into the following six groups: uncomplicated acute lung injury; respiratory failure complicated by multisystem failure; previous lung disease; trauma; other medical causes; and routine postoperative ventilation. During a one-year period, 327 patients required prolonged mechanical ventilation; acute lung injury and chronic obstructive pulmonary disease were the predominant conditions. Sepsis was both the major predisposing factor for and complication of acute lung injury. Mortality for patients with acute lung injury was 40 percent in the uncomplicated group and 81 percent in patients with acute lung injury complicated by multisystem failure. Acute respiratory failure in association with acute renal failure had a mortality of 89 percent. Number of organ systems involved also correlated with mortality. In patients with chronic obstructive pulmonary disease and pneumonitis or retained secretions, mortality was lower (30 percent), but a significant percentage of these patients (43 percent) became ventilator-dependent. Ventilator dependence did not significantly increase mortality during the course of respiratory failure.

Chronic eosinophilic pneumonia. Evidence for eosinophil degranulation and release of major basic protein

A patient with chronic eosinophilic pneumonia associated with ulcerative colitis and asthma is described. Exacerbations and remissions of these disorders paralleled each other. Pleural fluid and lung tissue contained high levels of eosinophil granule major basic protein, a substance with toxic effects on cells and tissues. The results indicate that eosinophils degranulate in the lung in eosinophilic pneumonia and point to the possibility that granule constituents damage lung tissue in the course of the disease.

Effect of resection of the sternum and manubrium in conjunction with muscle transposition on pulmonary function

We recorded the changes in pulmonary function that occurred after removal of the sternum and manubrium and repair by pectoralis major muscle transposition in six patients. Of these patients, three had osteomyelitis of the manubrium and sternum, two had osteosarcoma of the sternum, and one had osteomyelitis and radionecrosis of the manubrium and sternum. Body plethysmography and the rebreathing, hypercapnic ventilatory response test with inductive plethysmographic recordings of chest-wall motion were performed preoperatively and postoperatively. Preoperatively, four of the six patients had evidence of mild to moderate chest-wall restriction. Pulmonary function was normal in the other two patients. Postoperatively, total lung capacity was unchanged but the vital capacity decreased 11.5% in the overall group. Static compliance, retractive force, and the steady-state diffusing capacity for carbon monoxide decreased modestly but significantly postoperatively. The expiratory flow rates and maximal voluntary ventilation remained unchanged. Preoperatively, the slope of the hypercapnic ventilatory response was less than that predicted. Postoperatively, the slope did not change. In three patients, however, increased dependence on the abdomen for breathing suggested a dynamic restriction of rib-cage motion. On the basis of our findings, we conclude that surgical removal of the sternum and manubrium in conjunction with muscle flap repair is a well-tolerated procedure. Any postoperative changes in pulmonary function are minor.

Toxic shock syndrome, a newly recognized disease entity. Report of 11 cases

The toxic shock syndrome has only recently been described. Eleven female patients aged 13 to 43 years (median 17) with toxic shock syndrome have been seen at the Mayo Clinic since August 1975. One patient died. Seven patients had one or more recurrences. As previously described, the syndrome was often life-threatening, afflicted mostly menstruating females, and was characterized by a very brief prodromal illness consisting of high fever, vomiting, diarrhea, conjunctivitis, headache, irritability, sore throat, myalgias, abdominal tenderness, and erythematous rash. The disorder can progress to hypotension or prolonged refractory shock, adult respiratory distress syndrome, diffuse intravascular coagulation with severe thrombocytopenia, and renal failure. Pancreatitis was observed in two cases. During convalescence, pronounced desquamation and peeling of the skin occurred. Numerous laboratory abnormalities are observed. In 5 of the 11 patients, Staphylococcus aureus was isolated from conjunctiva, oral cavity or nares, vagina, or stool. A recently described pyrogenic exotoxin was identified in the isolates of three patients; its etiologic role remains speculative. Therapy is mainly supportive. Antistaphylococcal therapy for the acute illness and for prevention of recurrences has not yet proved to be of any benefit. The role of vaginal tampons, if any, in the pathogenesis of this disorder remains unclear.

Density dependence of maximal expiratory flow in chronic obstructive pulmonary disease

Pulmonary mechanics were studied in 22 patients with chronic obstructive pulmonary disease (COPD) who had no evidence of asthma. Eleven of the 22 patients had a density dependence of maximal expiratory flow within the reported normal range. Patients with normal density dependence (responders) were not different from those with decreased density dependence (nonresponders) in mean age, smoking history, symptoms of cough or dyspnea, maximal expiratory flow at 75, 50, and 25% of the vital capacity during air breathing, total lung capacity, or static elastic lung recoil at 50% of the vital capacity. The nonresponders had smaller vital capacity values, larger ratios of residual volume to total lung capacity, higher resistance, and lower static recoil at total lung capacity. There was a correlation between diffusing capacity for CO and density dependence. There was an inverse relationship between the change in density dependence after inhalation of isoproterenol and initial density dependence. Dysanaptic lung growth and increased compliance of the central airways are potential mechanisms for normal density dependence in these patients. The prevalence of normal density dependence in these patients with established COPD raises serious questions concerning the usefulness of density dependence in the early detection of COPD. The differences in density dependence may indicate differences in pathogenesis of the airflow obstruction and hence may be of prognostic significance.