Milk-induced pulmonary disease in infants (Heiner syndrome)

Clinical features and risk factors for recurrence of idiopathic pulmonary hemosiderosis in children

BACKGROUND

This study aims to review the clinical characteristics, therapeutic response and outcome of idiopathic pulmonary hemosiderosis (IPH), and discover the risk factors for recurrence in children with IPH, which will be helpful for the early diagnosis and reasonable treatment of this disease.

METHODS

Children with a diagnosis of IPH were enrolled in the study. Clinical data of the children were collected and analysed.

RESULTS

A total of 32 patients with regular follow-up after diagnosis were included in this study. Anaemia, cough and haemoptysis constituted the most common initial symptoms of the disease, and the incidences were 90.6%, 75% and 56.2%, respectively. The mean gap between the onset of symptoms and diagnosis was 5 (0.25-36) months. Most of the children experienced remission (complete and partial remission) over the course of 6 months of treatment, but 19 of the children experienced relapse. The causes of disease recurrence included respiratory tract infection (37.5%), corticosteroid (CS) reduction (18.8%), and irregular medication (6.3%). Interestingly, we found that children with history of allergy (HR 4.255, 1.107-16.356) tended to experience disease recurrence (p = 0.01).

CONCLUSIONS

Cough and anaemia are the most common symptoms in children with IPH. The recurrence rate of this disease is high, and respiratory tract infection is the most common cause of its recurrence. High-dose CS impluse therapy cannot reduce the recurrence rate of the disease. Allergic history was an import factor associated with disease recurrence.

TRIAL REGISTRATION

This study is a retrospective and observational study, which does not involve human specimens or clinical intervention. Therefore, clinical trial registration is not required, and there is no clinical trial number. However, the study was approved by the Institutional Review Board/Ethics Committee affiliated with West China Second University Hospital, Sichuan University (Ethics review number 2022074).

Updates in idiopathic pulmonary hemosiderosis in 2022: A state of the art review

This manuscript reports the recent advances in idiopathic pulmonary hemosiderosis (IPH), a rare cause of diffuse alveolar hemorrhage in children and adults. This narrative review of the literature summarizes different aspects of IPH, including proposed pathogenesis, patient demographics, clinical and radiological characteristics, treatment, and prognosis. Additionally, the association between Celiac Disease (CD) and IPH is carefully evaluated. IPH is a frequently misdiagnosed disease. The delay in the diagnosis of IPH is often significant but fortunately, appears to have decreased in recent years. IPH in adults and children have distinct demographic preferences. The autoantibodies are common in IPH but with a definite difference between the adult and pediatric populations. The definitive diagnosis of IPH requires lung biopsy and careful exclusion of all competing diagnoses, even with lung biopsy showing bland pulmonary hemorrhage. The presence of nonspecific inflammatory cells or lymphoid aggregates may suggest a secondary immunologic phenomenon and needs careful evaluation and follow-up. A substantial number of patients suffer from coexisting CD, also known as Lane-Hamilton syndrome (LHS), and all patients with IPH need to be evaluated for LHS by serology. Although strict gluten free diet can manage the majority of patients with LHS, other patients generally require immunosuppressive therapy. The corticosteroids are the backbone of IPH therapy. Recently utilized experimental treatment options include mesenchymal stem cell transplant, liposteroid and bronchial artery embolization. The immunosuppression should be adjusted to achieve optimal disease control. Patients may progress to end-stage lung disease despite all measures, and lung transplantation may be the only viable option.

Diagnosis and Rationale for Action against Cow's Milk Allergy (DRACMA) Guidelines update - III - Cow's milk allergens and mechanisms triggering immune activation

Background

The immunopathogenesis of cow's milk protein allergy (CMPA) is based on different mechanisms related to immune recognition of protein epitopes, which are affected by industrial processing.

Purpose

The purpose of this WAO DRACMA paper is to: (i) give a comprehensive overview of milk protein allergens, (ii) to review their immunogenicity and allergenicity in the context of industrial processing, and (iii) to review the milk-related immune mechanisms triggering IgE-mediated immediate type hypersensitivity reactions, mixed reactions and non-IgE mediated hypersensitivities.

Results

The main cow’s milk allergens – α-lactalbumin, β-lactoglobulin, serum albumin, caseins, bovine serum albumins, and others – may determine allergic reactions through a range of mechanisms. All marketed milk and milk products have undergone industrial processing that involves heating, filtration, and defatting. Milk processing results in structural changes of immunomodulatory proteins, leads to a loss of lipophilic compounds in the matrix, and hence to a higher allergenicity of industrially processed milk products. Thereby, the tolerogenic capacity of raw farm milk, associated with the whey proteins α-lactalbumin and β-lactoglobulin and their lipophilic ligands, is lost.

Conclusion

The spectrum of immunopathogenic mechanisms underlying cow's milk allergy (CMA) is wide. Unprocessed, fresh cow's milk, like human breast milk, contains various tolerogenic factors that are impaired by industrial processing. Further studies focusing on the immunological consequences of milk processing are warranted to understand on a molecular basis to what extent processing procedures make single milk compounds into allergens.

Respiratory Distress: Three Patient Cases

As mentioned in the January 2022 Pediatrics in Review Commentary, we now present three patients who have a common chief complaint followed by 5 questions for CME credit. All three cases have discussions on presentation, the differential diagnosis, and management that collectively serve as a Review article. The common theme here is that all three patients have difficulty breathing. We hope you will enjoy this review format.

Proposed Pathogenesis of Diffuse Alveolar Hemorrhage in Idiopathic Pulmonary Hemosiderosis

Idiopathic pulmonary hemosiderosis (IPH) is a rare disease that causes diffuse alveolar hemorrhage (DAH). The latest data suggests an immunologic origin of IPH, and a new name, immune mediated pulmonary hemosiderosis (ImPH), has been proposed. However, the exact immunologic mechanism has remained elusive for nearly eight decades despite extensive research, including detailed histopathologic analysis. Although several hypotheses have been proposed to describe the pathobiology of IPH, none of them explain the clinical and histopathologic findings conclusively. In this manuscript, we have presented a new hypothesis for the pathogenesis of DAH in IPH. We hypothesize that DAH in IPH is not immunocomplex mediated but due to histamine, eosinophilic cationic protein (ECP), and possibly vascular endothelial growth factor (VEGF). These bioactive proteins induce endothelial and alveolar epithelial damage, leading to the peri-capillary and intraalveolar escape of RBCs. The deformability of the RBC likely also plays a role. The supranormal secretion of histamine, ECP and VEGF occurs in genetically predisposed individuals with an aberrant immunologic response. The histamine is released from the basophils and possibly the mast cells in response to cytokines secreted by activated lymphocytes. The lymphocyte activation occurs after exposure to a known (gluten) or unknown antigen. The same lymphocyte-derived cytokines also induce eosinophilic degranulation of ECP and VEGF in the pulmonary circulation. We believe that our hypothesis unifies the observed clinical variabilities and histopathologic findings in IPH, and we hope that would promote future research in the field of IPH.

Children with Heiner Syndrome: A Single-Center Experience

Heiner syndrome is a rare cause of pulmonary hemosiderosis in children that is triggered by cow’s milk allergy. Herein, we describe our experience with three recent cases of Heiner syndrome with diverse clinical courses. We recommend that clinicians should consider the possibility of Heiner syndrome in children who exhibit characteristics of idiopathic pulmonary hemosiderosis.

Idiopathic pulmonary hemosiderosis: a review of the treatments used during the past 30 years and future directions

This paper reviews the literature on the treatment modalities for idiopathic pulmonary hemosiderosis (IPH) used over the past 30 years, attempting to define treatment options that appear to be efficacious and safe, and in addition presents a treatment algorithm. IPH is an uncommon etiology of diffuse alveolar hemorrhage. IPH is a rare disease in adults and often associated with a significant temporal delay in diagnosis. Patients present with hemoptysis, radiographic chest abnormalities, and iron deficiency anemia. Although several pathogenetic hypotheses have been proposed, IPH appears to be an immunologic disease, possibly with a genetic component. Corticosteroid therapy represents the first line of treatment, including liposome-incorporated dexamethasone palmitate (liposteroid). Additional immunomodulatory/immunosuppressive medications have been used with varying success, especially in the setting of steroid-refractory disease. Cyclophosphamide, azathioprine, hydroxychloroquine, mycophenolate mofetil, and mesenchymal cell transplantation have been attempted to improve outcome and reduce side effects. Controlled studies are needed to assess the optimal combination of medications, which are effective to control the disease.

Fever During Localized Inflammation in Mice Is Elicited by a Humoral Pathway and Depends on Brain Endothelial Interleukin-1 and Interleukin-6 Signaling and Central EP3 Receptors

We examined the signaling route for fever during localized inflammation in male and female mice, elicited by casein injection into a preformed air pouch. The localized inflammation gave rise to high concentrations of prostaglandins of the E species (PGE2) and cytokines in the air pouch and elevated levels of these inflammatory mediators in plasma. There were also elevated levels of PGE2 in the cerebrospinal fluid, although there was little evidence for PGE2 synthesis in the brain. Global deletion of the PGE2 prostaglandin E receptor 3 (EP3) abolished the febrile response as did deletion of the EP3 receptor in neural cells, whereas its deletion on peripheral nerves had no effect, implying that PGE2 action on this receptor in the CNS elicited the fever. Global deletion of the interleukin-1 receptor type 1 (IL-1R1) also abolished the febrile response, whereas its deletion on neural cells or peripheral nerves had no effect. However, deletion of the IL-1R1 on brain endothelial cells, as well as deletion of the interleukin-6 receptor α on these cells, attenuated the febrile response. In contrast, deletion of the PGE2 synthesizing enzymes cyclooxygenase-2 and microsomal prostaglandin synthase-1 in brain endothelial cells, known to attenuate fever evoked by systemic inflammation, had no effect. We conclude that fever during localized inflammation is not mediated by neural signaling from the inflamed site, as previously suggested, but is dependent on humoral signaling that involves interleukin actions on brain endothelial cells, probably facilitating PGE2 entry into the brain from the circulation and hence representing a mechanism distinct from that at work during systemic inflammation.

Heiner Syndrome and Milk Hypersensitivity: An Updated Overview on the Current Evidence

Infants affected by Heiner syndrome (HS) display chronic upper or lower respiratory tract infections, including otitis media or pneumonia. Clinically, gastrointestinal signs and symptoms, anemia, recurrent fever and failure to thrive can be also present. Chest X-rays can show patchy infiltrates miming pneumonia. Clinical manifestations usually disappear after a milk-free diet. The pathogenetic mechanism underlying HS remains unexplained, but the formation of immune complexes and the cell-mediated reaction have been proposed. Patients usually outgrow this hypersensitivity within a few years. The aim of this review is to provide an updated overview on the current evidence on HS in children, with a critical approach on the still undefined points of this interesting disease. Finally, we propose the first structured diagnostic approach for HS.

Risk factors for recurrent pulmonary exacerbation in idiopathic pulmonary hemosiderosis

OBJECTIVES

To evaluate the risk factors of recurrent pulmonary exacerbation and poor prognosis in children with idiopathic pulmonary hemosiderosis (IPH).

METHODS

In this multicenter study, 54 patients with a diagnosis of IPH were included. Medical records were retrospectively reviewed from three tertiary care hospitals between 1979 and 2019. Also, current information and the long-term progress of patients was determined by contacting the families by telephone.

RESULTS

A total of 54 children were included. The median age of onset of symptoms was 4.5 years (3 months to 15.8 years). The median time from onset to diagnosis was 0.9 years (0.25 months to 12 years). The mean number of recurrent episodes per child in the recurrence-positive group was 3.55 (1-15). Univariate analysis demonstrated that patients presenting with hypoxia or requiring transfusion at the time of presentation had significantly more recurrence episodes (p = .002). Multivariate analysis showed that the presence of hypoxia at the time of initial presentation was a significant independent predictor of recurrent episodes (p = .027). The median follow-up was 3.3 years (0.75 months to 27 years). There was a significant relationship between the presence of hypoxia, transfusion history, antinuclear antibody positivity, and elevated transaminases at the time of initial evaluation and treatment response.

CONCLUSIONS

The present study provides substantial information regarding factors that may affect recurrent exacerbations and prognosis in children with IPH. Demonstrating hypoxia as an independent risk factor in recurrence episodes could guide physicians in the planning of treatment strategies.

Idiopathic pulmonary hemosiderosis: A state of the art review

Idiopathic pulmonary hemosiderosis (IPH) is an uncommon cause of diffuse alveolar hemorrhage (DAH). Patients with IPH usually present with hemoptysis, and the diagnosis is often delayed by years. Patients often present with intermittent episodes of hemoptysis interspersed between periods of relative normalcy. However, massive hemorrhage resulting in acute respiratory failure and non-remitting hemoptysis have also been described. The classic triad includes hemoptysis, radiologic lung infiltrate, and iron deficiency anemia. Several hypotheses regarding the pathogenesis of IPH have been proposed. These risk factors include an autoimmune, allergic or genetic predisposition, and possible environmental exposure. Since IPH appears to be responsive to corticosteroids, the autoimmune hypothesis is considered to play a crucial role. A diagnosis of IPH requires exclusion of other etiologies of DAH, including infection, medications, toxic inhalation, vasculitis, and anti-glomerular basement membrane disease, among others. Histologically, IPH is characterized by the presence of hemosiderin-laden macrophages in the alveolar space without any evidence of vasculitis or immunocomplex deposition. Corticosteroid therapy represents the primary modality of treatment. Other immunosuppressive medications have also been used with varying success, especially in the setting of steroid-refractory disease. The prognosis of IPH in adults is somewhat better compared to the pediatric population. The severity of the initial presentation does not predict future outcomes. Which risk factors and patient characteristics are associated with a poor outcome are also unknown. More research is necessary to elucidate the pathophysiology and appropriate treatment.

Epidemiology of rare allergic diseases in children

Allergic diseases have different frequencies. In particular, allergic rhinitis and asthma have high frequencies of about 20% and 10%, respectively. Other allergic diseases have lower frequencies; for example, food allergy has a frequency of 1%-4%. There are also rare allergic diseases, with a prevalence of 5 cases per 10 000 people in the general population, and they are included in Orphanet. However, other extremely rare allergic diseases still need to be properly known in order to be possibly recognized as rare diseases and cataloged in Orphanet.

Diffuse alveolar hemorrhage in infants: Report of five cases

Diffuse alveolar hemorrhage (DAH) is a rare life-threatening condition in children. In this entity, the bleeding originates from the pulmonary microvasculature as a result of microvascular damage leading to blood leakage into the alveolar spaces. DAH can occur as an isolated medical entity or may be associated with other organ system injury or dysfunction. The classic triad of symptoms includes hemoptysis, anemia and diffuse pulmonary infiltrates. Hemoptysis is the usual presenting symptom but is not constant. A variety of diseases is associated with the development of DAH. Current classification organize the etiologies of diffuse alveolar hemorrhage based on the presence of severe immune disorders (such as systemic vasculitis and collagenosis) or non-immunodeficiency disorders (with an identified cardiac or non-cardiac origin, or idiopathic). The five cases of DAH presented in this study were all diagnosed in full-term infants, four males and one female, with normal neonatal adaptation and without family history of notable diseases. In all cases the diagnosis was made between the age of three and eighteen weeks-old. Moreover, all five patients, at the time of diagnosis, presented with hemoptysis, mild or severe dyspnea, anemia and abnormal chest X-rays. Consequently, the diagnosis of DAH was strongly suspected and, eventually, confirmed by bronchoscopy. Additional laboratory tests, as well as selected serologic and radiographic studies were performed in order to identify a specific etiology. The final diagnoses reflect a variety of causes: infections, idiopathic pulmonary hemosiderosis, accidental suffocation and Heiner syndrome. Treatment included oral corticosteroids except from one patient that received antimicrobial therapy.

Autoimmunity and Delayed Diagnosis in Pediatric Idiopathic Pulmonary Hemosiderosis

Idiopathic pulmonary hemosiderosis is characterized by a triad of iron-deficiency anemia, hemoptysis, and radiographic diffuse lung infiltrates. However, the inconsistent initial presentation in children may cause a significant delay in diagnosis. Autoimmune reactivity seems to be the most acceptable theory of pathogenesis. We reported an 8-year-old boy presenting with a cough, fever, and difficulty breathing with a history of iron-deficiency anemia and an abnormal autoimmune response in the last 3 years. Perinuclear antineutrophil cytoplasmic antibodies were positive and chest computed tomography revealed patchy ground glass haziness. Bronchoalveolar lavage fluid showed hemosiderin-laden macrophages. The respiratory symptoms improved with oral corticosteroids.

Heiner Syndrome: An uncommon cause of failure to thrive

Heiner syndrome (HS) is a rare hypersensitivity reaction of an infant or young child to cow milk proteins. It is a disease characterised by failure to thrive, respiratory symptoms like cough, dyspnoea, wheeze and rhinitis with accompanying chest infiltrates on chest radiograph; gastrointestinal symptoms like vomiting, diarrhoea; and anaemia. The non-specific nature of the disease can result in delayed diagnosis and treatment and central to the condition is hypersensitivity to cow milk proteins.

Several cases have been reported worldwide but there has been no report of this condition in Africa.

We highlight the case of a sixteen week old child seen in our facility with features typical of Heiner syndrome. Clinicians should have a high index of suspicion for this condition especially in children predominantly on infant formula.

A different clinical presentation of Heiner syndrome: The case of diffuse alveolar hemorrhage causing massive hemoptysis and hematemesis

Heiner syndrome is a non-IgE-mediated hypersensitivity to cow's milk, which often causes pulmonary disease in infants and young children. Patients often have symptoms of chronic or recurrent upper or lower respiratory tract infection. It has been reported that the Heiner's syndrome can cause recurrent pulmonary hemorrhage, and it is difficult to differentiate from the entity of idiopathic pulmonary hemosiderosis, another disease with recurrent pulmonary hemorrhage of unknown etiology usually occurring in the older children. Acute respiration is a rare problem in Heiner syndrome, which usually has symptoms and signs of chronic respiratory disease. In this case report, we present a 6-month-old patient who was admitted to our hospital with massive hemoptysis, hematemesis, and deep anemia.

Hematochezia in a Child With Heiner Syndrome

Heiner syndrome (HS) is a food hypersensitivity disease that is mostly caused by cow's milk. The main features may include chronic or recurrent respiratory syndromes, pulmonary infiltrates on radiography, and even pulmonary hemosiderosis. However, gastrointestinal symptoms are rare in HS, which can lead to a misdiagnosis when the chief complaint is about the gastrointestinal system. Here, we report a case of HS complicated by severe hematochezia.

Pulmonary hemosiderosis in children with Down syndrome: a national experience

BACKGROUND

Pulmonary hemosiderosis is a rare and complex disease in children. A previous study from the French RespiRare® network led to two important findings: 20% of the children presented with both pulmonary hemosiderosis and Down syndrome (DS), and at least one tested autoantibody was found positive in 50%. This study investigates the relationships between pulmonary hemosiderosis and DS.

METHODS

Patients younger than 20 years old and followed for pulmonary hemosiderosis were retrieved from the RespiRare® database. Clinical, biological, functional, and radiological findings were collected, and DS and non-DS patients' data were compared.

RESULTS

A total of 34 patients (22 girls and 12 boys) were included, among whom nine (26%) presented with DS. The mean age at diagnosis was 4.1 ± 3.27 years old for non-DS and 2.9 ± 3.45 years old for DS patients. DS patients tended to present a more severe form of the disease with an earlier onset, more dyspnoea at diagnosis, more frequent secondary pulmonary hypertension, and an increased risk of fatal evolution.

CONCLUSIONS

DS patients have a higher risk of developing pulmonary hemosiderosis, and the disease seems to be more severe in this population. This could be due to the combination of an abnormal lung capillary bed with fragile vessels, a higher susceptibility to autoimmune lesions, and a higher risk of evolution toward pulmonary hypertension. A better screening for pulmonary hemosiderosis and a better prevention of hypoxia in DS paediatric patients may prevent a severe evolution of the disease.

Comparing immediate-type food allergy in humans and companion animals-revealing unmet needs

Adverse food reactions occur in human as well as veterinary patients. Systematic comparison may lead to improved recommendations for prevention and treatment in both. In this position paper, we summarize the current knowledge on immediate-type food allergy vs other food adverse reactions in companion animals, and compare this to the human situation. While the prevalence of food allergy in humans has been well studied for some allergens, this remains to be investigated for animal patients, where owner-reported as well as veterinarian-diagnosed food adverse reactions are on the increase. The characteristics of the disease in humans vs dogs, cats, and horses are most often caused by similar, but sometimes species-dependent different pathophysiological mechanisms, prompting the specific clinical symptoms, diagnoses, and treatments. Furthermore, little is known about the allergen molecules causative for type I food allergy in animals, which, like in human patients, could represent predictive biomarkers for risk evaluation. The definite diagnosis of food allergy relies-as in humans-on elimination diet and provocation tests. Besides allergen avoidance in daily practice, novel treatment options and tolerization strategies are underway. Taken together, numerous knowledge gaps were identified in veterinary food allergy, which need to be filled by systematic comparative studies.

Eosinophilic Lung Disease

Eosinophils are involved in the pathogenesis of a number of lung diseases. Recent advances in eosinophil biology have now produced clinically applicable therapies that seek to counter eosinophilia in blood and lungs. This article reviews the basic biology of eosinophils and their role in mediating T-helper 2 cell responses. The current status of anticytokine therapy for eosinophilic lung disease is discussed. A clinical approach to eosinophilic lung disease based on symptoms and radiography is generated. The clinical significance of persistent eosinophilia in lung transplant patients and patients with asthma will receive special emphasis.

The Role and Immunobiology of Eosinophils in the Respiratory System: a Comprehensive Review

The eosinophil is a fully delineated granulocyte that disseminates throughout the bloodstream to end-organs after complete maturation in the bone marrow. While the presence of eosinophils is not uncommon even in healthy individuals, these granulocytes play a central role in inflammation and allergic processes. Normally appearing in smaller numbers, higher levels of eosinophils in the peripheral blood or certain tissues typically signal a pathologic process. Eosinophils confer a beneficial effect on the host by enhancing immunity against molds and viruses. However, tissue-specific elevation of eosinophils, particularly in the respiratory system, can cause a variety of short-term symptoms and may lead to long-term sequelae. Eosinophils often play a role in more commonly encountered disease processes, such as asthma and allergic responses in the upper respiratory tract. They are also integral in the pathology of less common diseases including eosinophilic pneumonia, allergic bronchopulmonary aspergillosis, hypersensitivity pneumonitis, and drug reaction with eosinophilia and systemic symptoms. They can be seen in neoplastic disorders or occupational exposures as well. The involvement of eosinophils in pulmonary disease processes can affect the method of diagnosis and the selection of treatment modalities. By analyzing the complex interaction between the eosinophil and its environment, which includes signaling molecules and tissues, different therapies have been discovered and created in order to target disease processes at a cellular level. Innovative treatments such as mepolizumab and benralizumab will be discussed. The purpose of this article is to further explore the topic of eosinophilic presence, activity, and pathology in the respiratory tract, as well as discuss current and future treatment options through a detailed literature review.

Signs and Symptoms of Food Allergy and Food-Induced Anaphylaxis

Food allergies are increasing in prevalence. In order for pediatric clinicians to appropriately diagnose and manage food allergies, the characteristic signs and symptoms of these potentially severe reactions must be recognized. Unlike nonimmunologic adverse food reactions (such as lactose intolerance and food poisoning), food allergies by definition are immune-mediated responses that occur reproducibly on food ingestion. The varying clinical presentations of food allergy include IgE-mediated disorders, mixed IgE- and cell-mediated disorders, and cell-mediated food allergies. This review describes the clinical manifestations of each of these categories of food allergy, with special emphasis on recognition of food-induced anaphylaxis.

Diagnosis of Food Allergy

The prevalence of food allergies has been on the increase over the last 2 decades. Diagnosing food allergies can be complicated, as there are multiple types that have distinct clinical and immunologic features. Food allergies are broadly classified into immunoglobulin E (IgE)-mediated, non-IgE-mediated, or mixed food allergic reactions. This review focuses on the clinical manifestations of the different categories of food allergies and the different tests available to guide the clinician toward an accurate diagnosis.

Chronic cough in children

Cough is probably the most common cause of seeking medical care in pediatric practice. Most acute cough is caused by infection and usually resolves within less than 4 weeks. If it lasts longer, it is considered chronic and deserves investigation to identify the underlying cause, which can be almost any of a wide variety of illnesses of the respiratory tract and certain extrathoracic conditions. This review provides an optimal approach for diagnosis through a skillful history taking, physical examination, and selection of appropriate tests.

Diffuse Lung Disease

Diffuse lung disease (DLD) comprises a diverse group of disorders characterized by widespread pulmonary parenchymal pathology and impaired gas exchange. While many of these disorders are categorized under the rubric of interstitial lung disease (ILD), some of these disorders involve the airspaces or peripheral airways in addition to, or rather than, the interstitium. Some of these disorders are present primarily in infancy or early childhood, while others that are prevalent in adulthood rarely occur in childhood. This chapter will review the classification of pediatric DLD and the characteristic imaging findings of specific disorders to facilitate accurate diagnosis and guide appropriate treatment of children with these disorders.

New insights into pediatric idiopathic pulmonary hemosiderosis: the French RespiRare(®) cohort

BACKGROUND

Idiopathic pulmonary hemosiderosis (IPH) is a rare cause of alveolar hemorrhage in children and its pathophysiology remains obscure. Classically, diagnosis is based on a triad including hemoptysis, diffuse parenchymal infiltrates on chest X-rays, and iron-deficiency anemia. We present the French pediatric cohort of IPH collected through the French Reference Center for Rare Lung Diseases (RespiRare®, http://www.respirare.fr).

METHODS

Since 2008, a national network/web-linked RespiRare® database has been set up in 12 French pediatric respiratory centres. It is structured as a medical recording tool with extended disease-specific datasets containing clinical information relevant to all forms of rare lung diseases including IPH.

RESULTS

We identified 25 reported cases of IPH in children from the database (20 females and 5 males). Among them, 5 presented with Down syndrome. Upon diagnosis, median age was 4.3 [0.8-14.0] yrs, and the main manifestations were: dyspnea (n = 17, 68%), anemia (n = 16, 64%), cough (n = 12, 48%), febrile pneumonia (n = 11, 44%) and hemoptysis (n = 11, 44%). Half of the patients demonstrated diffuse parenchymal infiltrates on chest imaging, and diagnosis was ascertained either by broncho-alveolar lavage indicating the presence of hemosiderin-laden macrophages (19/25 cases), or lung biopsy (6/25). In screened patients, initial auto-immune screening revealed positive antineutrophilic cytoplasmic antibodies (ANCA) (n = 6, 40%), antinuclear antibodies (ANA) (n = 5, 45%) and specific coeliac disease antibodies (n = 4, 28%). All the patients were initially treated by corticosteroids. In 13 cases, immunosuppressants were introduced due to corticoresistance and/or major side effects. Median length of follow-up was 5.5 yrs, with a satisfactory respiratory outcome in 23/25 patients. One patient developed severe pulmonary fibrosis, and another with Down syndrome died as a result of severe pulmonary hemorrhage.

CONCLUSION

The present cohort provides substantial information on clinical expression and outcomes of pediatric IPH. Analysis of potential contributors supports a role of auto-immunity in disease development and highlights the importance of genetic factors.

New insights into pediatric idiopathic pulmonary hemosiderosis: the French RespiRare(®) cohort

BACKGROUND

Idiopathic pulmonary hemosiderosis (IPH) is a rare cause of alveolar hemorrhage in children and its pathophysiology remains obscure. Classically, diagnosis is based on a triad including hemoptysis, diffuse parenchymal infiltrates on chest X-rays, and iron-deficiency anemia. We present the French pediatric cohort of IPH collected through the French Reference Center for Rare Lung Diseases (RespiRare®, http://www.respirare.fr).

METHODS

Since 2008, a national network/web-linked RespiRare® database has been set up in 12 French pediatric respiratory centres. It is structured as a medical recording tool with extended disease-specific datasets containing clinical information relevant to all forms of rare lung diseases including IPH.

RESULTS

We identified 25 reported cases of IPH in children from the database (20 females and 5 males). Among them, 5 presented with Down syndrome. Upon diagnosis, median age was 4.3 [0.8-14.0] yrs, and the main manifestations were: dyspnea (n = 17, 68%), anemia (n = 16, 64%), cough (n = 12, 48%), febrile pneumonia (n = 11, 44%) and hemoptysis (n = 11, 44%). Half of the patients demonstrated diffuse parenchymal infiltrates on chest imaging, and diagnosis was ascertained either by broncho-alveolar lavage indicating the presence of hemosiderin-laden macrophages (19/25 cases), or lung biopsy (6/25). In screened patients, initial auto-immune screening revealed positive antineutrophilic cytoplasmic antibodies (ANCA) (n = 6, 40%), antinuclear antibodies (ANA) (n = 5, 45%) and specific coeliac disease antibodies (n = 4, 28%). All the patients were initially treated by corticosteroids. In 13 cases, immunosuppressants were introduced due to corticoresistance and/or major side effects. Median length of follow-up was 5.5 yrs, with a satisfactory respiratory outcome in 23/25 patients. One patient developed severe pulmonary fibrosis, and another with Down syndrome died as a result of severe pulmonary hemorrhage.

CONCLUSION

The present cohort provides substantial information on clinical expression and outcomes of pediatric IPH. Analysis of potential contributors supports a role of auto-immunity in disease development and highlights the importance of genetic factors.

Recognition and management of pediatric food allergy in the emergency department

Recently, the National Institute of Allergy and Infectious Diseases sought to establish consistency in definitions, diagnostic criteria, and management practices concerning food allergies (FAs). This review aimed to summarize and highlight the relevant findings of these guidelines for the emergency department provider, as pediatric patients often present to the emergency department with FAs or other disorders mimicking FAs.

A national internet-linked based database for pediatric interstitial lung diseases: the French network

BACKGROUND

Interstitial lung diseases (ILDs) in children represent a heterogeneous group of rare respiratory disorders that affect the lung parenchyma. After the launch of the French Reference Centre for Rare Lung Diseases (RespiRare®), we created a national network and a web-linked database to collect data on pediatric ILD.

METHODS

Since 2008, the database has been set up in all RespiRare® centres. After patient's parents' oral consent is obtained, physicians enter the data of children with ILD: identity, social data and environmental data; specific aetiological diagnosis of the ILD if known, genetics, patient visits to the centre, and all medical examinations and tests done for the diagnosis and/or during follow up. Each participating centre has a free access to his own patients' data only, and cross-centre studies require mutual agreement. Physicians may use the system as a daily aid for patient care through a web-linked medical file, backed on this database.

RESULTS

Data was collected for 205 cases of ILD. The M/F sex ratio was 0.9. Median age at diagnosis was 1.5 years old [0-16.9]. A specific aetiology was identified in 149 (72.7%) patients while 56 (27.3%) cases remain undiagnosed. Surfactant deficiencies and alveolar proteinosis, haemosiderosis, and sarcoidosis represent almost half of the diagnoses. Median length of follow-up is 2.9 years [0-17.2].

CONCLUSIONS

We introduce here the French network and the largest national database in pediatric ILDs. The diagnosis spectrum and the estimated incidence are consistent with other European databases. An important challenge will be to reduce the proportion of unclassified ILDs by a standardized diagnosis work-up. This database is a great opportunity to improve patient care and disease pathogenesis knowledge. A European network including physicians and European foundations is now emerging with the initial aim of devising a simplified European database/register as a first step to larger European studies.

Non-IgE-mediated cow milk allergy is linked to early childhood clusters of commonly seen illnesses: a pilot study

OBJECTIVE

There are few established diagnostic tools to define non-IgE-mediated food hypersensitivity reactions. Cow milk protein allergy (CMPA) is a multisystem disorder affecting the gastrointestinal, skin, and lower and upper airway systems. This link is frequently missed because of subspecialty evaluation of the multisystem effects individually. The authors hypothesize that a more global evaluation based on a simple scored questionnaire will reveal this link.

METHODS

Over an 18-month period, children younger than 2 years with non-IgE-mediated CMPA were identified. A symptom questionnaire was developed and scored and also applied to a control population. The prevalence of symptoms in each group was compared and a cumulative score was determined. Symptoms evaluated included gastrointestinal, aerodigestive, lower airway, and skin symptoms. A positive response was scored 1 and a negative response scored 0.

RESULTS

Significant differences in prevalence rates between CMPA and control populations were noted, particularly in aerodigestive symptoms. There were marked differences in cumulative score between populations (P < .001). The authors identified a cut-off score at which there was close to 80% sensitivity and 90% specificity for distinguishing CMPA from a control population.

CONCLUSION

A global evaluation of multiple systems can be an important diagnostic tool in determining CMPA in infants.

Primary care management of food allergy and food intolerance

The incidence of food allergies is steadily increasing. Due to potentially life-threatening complications, it is important that primary care providers recognize and appropriately manage these disorders. This article includes a discussion of the current evidence-based guidelines for the diagnosis, screening, and management of food allergies.

Lane-Hamilton syndrome: case report and review of the literature

We report a case of a three-and-a-half-year-old boy, who presented with poor general condition, stunted growth, had the presence of nail clubbing, persistent cough and frequent diarrhoea. Persistent iron deficiency anaemia without signs of haemolysis suggested Lane-Hamilton syndrome (LHS) which is or/is an extremely rare combination of idiopathic pulmonary haemosiderosis (IPH) and celiac disease (CD), although both diseases are immunologically mediated and the pathogenetic link between them is not clear. We have now 3 years of follow-up on gluten-free diet (GFD), resulting in a gradual recovery of the abnormal laboratory results in combination with an improving growth. Clinically, he is asymptomatic without any additional treatment. Our case illustrates that CD should be specifically looked for in patients with IPH, especially those in whom the severity of anaemia is disproportionate to the IPH symptoms. Both diseases may benefit from a GFD.

Diagnosis and Rationale for Action Against Cow's Milk Allergy (DRACMA): a summary report

The 2nd Milan Meeting on Adverse Reactions to Bovine Proteins was the venue for the presentation of the first consensus-based approach to the management of cow's milk allergy. It was also the first time that the Grading of Recommendations, Assessments, Development, and Evaluation approach for formulating guidelines and recommendations was applied to the field of food allergy. In this report we present the contributions in allergen science, epidemiology, natural history, evidence-based diagnosis, and therapy synthesized in the World Allergy Organization Diagnosis and Rationale for Action against Cow's Milk Allergy guidelines and presented during the meeting. A consensus emerged between discussants that cow's milk allergy management should reflect not only basic research but also a newer and better appraisal of the literature in the light of the values and preferences shared by patients and their caregivers in partnership. In the field of diagnosis, atopy patch testing and microarray technology have not yet evolved for use outside the research setting. With foreseeable breakthroughs (eg, immunotherapy and molecular diagnosis) in the offing, the step ahead in leadership can only stem from a worldwide organization implementing consensus-based clinical practice guidelines to diffuse and share clinical knowledge.

Clinical presentations of food allergy

Food allergies are immune-mediated responses to food proteins. Because of differences in the underlying immunologic mechanisms, there are varying clinical presentations of food allergy. This article discusses the manifestations of IgE-mediated disorders, including urticaria and angioedema, rhinoconjunctivitis, asthma, gastrointestinal anaphylaxis, generalized anaphylaxis, food-dependent exercise-induced anaphylaxis, and oral allergy syndrome. It also reviews the presentations of mixed IgE- and cell-mediated disorders, including atopic dermatitis and eosinophilic gastrointestinal disorders. Finally, the manifestations of cell-mediated food allergies are discussed, including dietary protein-induced proctitis and proctocolitis, food protein-induced enterocolitis syndrome, celiac disease, and food-induced pulmonary hemosiderosis.

Milk and soy allergy

Cow's milk allergy (CMA) affects 2% to 3% of young children and presents with a wide range of IgE and non-IgE-mediated clinical syndromes, which have a significant economic and lifestyle effect. It is logical that a review of CMA would be linked to a review of soy allergy because soy formula is often an alternative source of nutrition for infants who do not tolerate cow's milk. This review examines the epidemiology, pathogenesis, clinical features, natural history, and diagnosis of cow's milk and soy allergy. Cross-reactivity and management of milk allergy are also discussed.

A Review of Food Allergy and Nutritional Considerations in the Food-Allergic Adult

In the United States, the prevalence of adults with food allergies is approximately 2% to 3%. Theoretically, any food can cause an allergic reaction; however, some foods are clearly more allergenic than others. In adults, peanuts, tree nuts, finned fish, crustaceans, fruit, and vegetables account for 85% of the food-allergic reactions. Currently, the only ways to manage food allergies are to avoid the allergen and initiate therapy for an allergic reaction if ingestion does occur. The presence of homologous proteins among animal or plant foods and between foods and certain airborne allergens may account for cross-sensitization that may be clinically relevant. For inpatients or outpatients with food allergies, nutrient and fluid requirements are the same as for individuals without food allergies. Since patients with adverse reactions to food may self-restrict intake or have been counseled on food avoidance, it is particularly important to determine dietary adequacy and to provide patients with appropriate food substitutions to provide nutrients that may be missing from a patient’s diet. This is of particular concern for individuals with multiple food allergies. Eating away from home and traveling also pose special problems for those with food allergies.

Interstitial lung diseases in children

Interstitial lung disease (ILD) in infants and children comprises a large spectrum of rare respiratory disorders that are mostly chronic and associated with high morbidity and mortality. These disorders are characterized by inflammatory and fibrotic changes that affect alveolar walls. Typical features of ILD include dyspnea, diffuse infiltrates on chest radiographs, and abnormal pulmonary function tests with restrictive ventilatory defect and/or impaired gas exchange. Many pathological situations can impair gas exchange and, therefore, may contribute to progressive lung damage and ILD. Consequently, diagnosis approach needs to be structured with a clinical evaluation requiring a careful history paying attention to exposures and systemic diseases. Several classifications for ILD have been proposed but none is entirely satisfactory especially in children. The present article reviews current concepts of pathophysiological mechanisms, etiology and diagnostic approaches, as well as therapeutic strategies. The following diagnostic grouping is used to discuss the various causes of pediatric ILD: 1) exposure-related ILD; 2) systemic disease-associated ILD; 3) alveolar structure disorder-associated ILD; and 4) ILD specific to infancy. Therapeutic options include mainly anti-inflammatory, immunosuppressive, and/or anti-fibrotic drugs. The outcome is highly variable with a mortality rate around 15%. An overall favorable response to corticosteroid therapy is observed in around 50% of cases, often associated with sequelae such as limited exercise tolerance or the need for long-term oxygen therapy.

Regulation and dysregulation of immunoglobulin E: a molecular and clinical perspective

BACKGROUND

Altered levels of Immunoglobulin E (IgE) represent a dysregulation of IgE synthesis and may be seen in a variety of immunological disorders. The object of this review is to summarize the historical and molecular aspects of IgE synthesis and the disorders associated with dysregulation of IgE production.

METHODS

Articles published in Medline/PubMed were searched with the keyword Immunoglobulin E and specific terms such as class switch recombination, deficiency and/or specific disease conditions (atopy, neoplasia, renal disease, myeloma, etc.). The selected papers included reviews, case reports, retrospective reviews and molecular mechanisms. Studies involving both sexes and all ages were included in the analysis.

RESULTS

Both very low and elevated levels of IgE may be seen in clinical practice. Major advancements have been made in our understanding of the molecular basis of IgE class switching including roles for T cells, cytokines and T regulatory (or Treg) cells in this process. Dysregulation of this process may result in either elevated IgE levels or IgE deficiency.

CONCLUSION

Evaluation of a patient with elevated IgE must involve a detailed differential diagnosis and consideration of various immunological and non-immunological disorders. The use of appropriate tests will allow the correct diagnosis to be made. This can often assist in the development of tailored treatments.

Localized inflammation in peripheral tissue signals the CNS for sickness response in the absence of interleukin-1 and cyclooxygenase-2 in the blood and brain

The CNS can be activated by both local and systemic inflammation, resulting in the manifestation of sickness symptoms. The pathways by which the CNS is activated under these two conditions, however, may differ. In this study, we injected casein into the peritoneal cavity (i.p.) or into an s.c. air pouch of mice to induce restricted local inflammation. Both routes of casein injection caused fever and reduced locomotor activity. These responses were not accompanied by the statistically significant induction of the inflammatory cytokine interleukin-1 (IL-1) in the blood and brain. Further, these responses were produced without the induction of brain cyclooxygenase-2 (COX-2), which has been implicated as an obligatory step in systemic inflammation-induced activation of the CNS. Induction of IL-1, interleukin-6 (IL-6), and COX-2, however, was found consistently at the sites of casein injection. The local inflammation-induced febrile and locomotor activity responses were blunted in animals deficient in functional Toll-like receptor 4 (TLR4), type I interleukin-1 receptor (IL-1R1), IL-6, or COX-2. Therefore, the observed febrile and locomotor activity effects appear to require local, but not central, IL-1, IL-6, and COX-2. These findings suggest that local inflammation can activate the CNS via pathways distinguishable from those mediating systemic inflammation-induced CNS activation.

Screening for celiac disease in idiopathic pulmonary hemosiderosis

AIM

The aim of this report was to screen for celiac disease (CD) in patients with idiopathic pulmonary hemosiderosis (IPH).

PATIENTS AND METHODS

Patients with IPH treated at the Children's Hospital of Tunis between 1976 and 2006 were reviewed and investigated for CD, using serological and histological tests.

RESULTS

A total of 10 children (two boys and eight girls) had IPH. The mean age at diagnosis was 3.1 years. Three had digestive symptoms and positive CD serology, which was confirmed by histological data. Clinical and radiological findings improved markedly in all CD patients with corticosteroid treatment combined with a gluten-free diet. Symptoms of IPH and CD both returned in one patient who stopped the gluten-free diet.

CONCLUSION

Three of our 10 patients with IPH also had CD. These data illustrate the close etiopathogenic link between IPH and CD, and strongly suggest that CD be looked for in IPH patients, especially in those with symptoms suggestive of CD.

Diffuse alveolar hemorrhage syndromes in children

PURPOSE OF REVIEW

In this review we discuss the changing concepts of diffuse alveolar hemorrhage in children in terms of an expanded differential diagnosis and new approaches to diagnosis and treatment.

RECENT FINDINGS

More commonly found in adults, pulmonary capillaritis, an immune-mediated form of diffuse alveolar hemorrhage often associated with systemic disease, has been recently reported in children. In a series of eight children with pulmonary capillaritis, serology for immune-mediated disorders was positive in only half. Acute idiopathic pulmonary hemorrhage is a unique condition of infants who present with acute pulmonary hemorrhage and respiratory failure. The hypothesis that acute idiopathic pulmonary hemorrhage is caused by toxigenic mold has not been proven, and its cause remains uncertain.

SUMMARY

Classification of diffuse alveolar hemorrhage in children has been revised to include those conditions with and without pulmonary capillaritis. As idiopathic pulmonary hemosiderosis, the classic form of diffuse alveolar hemorrhage in children, is a diagnosis of exclusion and children with pulmonary capillaritis may have negative serology, lung biopsy should be strongly considered in any child with diffuse alveolar hemorrhage without a cardiovascular cause. Generally, patients with immune-mediated lung disease require more aggressive pharmacologic intervention.

Quantification of siderophages in bronchoalveolar fluid in transfusional and primary pulmonary hemosiderosis

Transfusional iron overload may occur in the lungs. We hypothesized that quantitating siderophages in the bronchoalveolar fluid (BALF) of heavily transfused patients may prove to be a useful tool in determining lung iron overload in transfusion-dependent patients. The study included six patients (7-20 years) with thalassemia major (TM) who had received multiple blood transfusions, one with hereditary spherocytosis (four blood transfusions) and one with sickle cell disease (never transfused); they were compared to three children with idiopathic pulmonary hemosiderosis (IPH) (2.5-7.0 years) as positive controls. Fiberoptic bronchoscopy with bronchoalveolar lavage was performed in seven patients under general anesthesia for elective surgery and the rest were bronchoscoped electively under sedation. Spirometry was also performed in eight patients. There was no significant difference between children with TM and IPH in siderophages as percentage of total count (95% CI -31.0 to 1.5, P = 0.068). There were positive relationships between both mean serum ferritin values during the preceding year and the total number of units of transfused blood, and percent siderophage count among multiply transfused patients (P = 0.010, P = 0.052, respectively); similar findings were noted for the Golde score (P = 0.001, P = 0.031, respectively). None of the patients showed lung function impairment. In conclusion, in this small study, we found that the BALF of multiply transfused patients with benign hematological disorders contain similar numbers of siderophages to that of patients with IPH; this is strongly suggestive of secondary pulmonary hemosiderosis. The correlation between the patients' serum ferritin, and the BALF siderophages suggests that the later may serve as a marker of pulmonary iron overload in patients requiring blood transfusion and appear to be more sensitive than standard pulmonary function tests.