Hypereosinophiles Syndrom und Churg-Strauss-Syndrom

[Eosinophilic granulomatosis with polyangiitis : Update on classification and management]

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare chronic inflammatory systemic disease that occurs in patients with bronchial asthma and is associated with significant blood and tissue eosinophilia. Another characteristic is vasculitis of small and/or medium-sized vessels, which may be absent in prodromal stages of the disease and is therefore no longer an obligatory part of the disease definition. Antineutrophil cytoplasmic antibodies (ANCA) can be detected in approximately one third of patients. The ANCA-positive and ANCA-negative EGPA are genetically distinct diseases with common clinical manifestations, which, however, occur with different frequencies. Cardiac involvement is associated with a poor prognosis. Permanent organ damage often occurs as a result of the underlying disease or treatment, especially with glucocorticoids (GC). The standard treatment of EGPA consists of GC in combination with cyclophosphamide for severe organ involvement or medium potency immunosuppressants for more prognostically favorable manifestations. Biologics are increasingly being used in the treatment of EGPA. The interleukin (IL) 5 antagonist mepolizumab reduces the risk of relapses and decreases the demand for GC in patients with relapsing EGPA without severe organ involvement. In analogy to the approach to other ANCA-associated vasculitides, the use of rituximab in ANCA-positive EGPA patients with severe vasculitis recurrence is a possible option, even though formal evidence for such an approach is currently low and formal approval is lacking.

Two Immunocompromised Patients With Diffuse Alveolar Hemorrhage as a Complication of Severe Coronavirus Disease 2019

Diffuse alveolar hemorrhage (DAH) is a severe and potentially life-threatening disease manifestation. In addition to autoimmune diseases such as antineutrophil cytoplasmic antibody-associated vasculitis and anti-glomerular basement membrane syndrome, pulmonary viral infections are known to be culprits of DAH. Health-care providers worldwide in the coronavirus disease 2019 pandemic have been confronted with an unprecedented number of viral lung infections, with great variance in symptoms and severity. Hemoptysis, the key symptom of DAH, is a rare complication. We present two cases of immunocompromised patients with rapidly developing hypoxemic respiratory failure and evidence of DAH in the context of severe acute respiratory syndrome coronavirus 2 infection.

[Differential diagnosis of hypereosinophilia]

Eosinophilia is defined as an elevated absolute number of eosinophilic leukocytes in peripheral blood or tissue. Its absolute number also defines the grade of eosinophilia. The main causes are allergic (including drug side effects) and infectious triggers but malignant and autoimmune diseases can also result in eosinophilia. Severe eosinophilia with the number of eosinophils >5000/µl are mostly caused by myeloproliferative disorders, eosinophilic granulomatosis with polyangiitis or during tissue migration in parasitic tissue infections. Hypereosinophilic syndrome is defined as eosinophilia with >1500 eosinophils/µl and a duration of more than 6 months by exclusion of parasitic infections, allergies or other causes of tissue eosinophilia with end-organ damage. For the diagnosis of a persistent eosinophilia a detailed medical history and physical examination should be followed by early organ screening, infection diagnostics especially for helminth infections and hematological laboratory analyses including bone marrow investigations.

Occam’s razor reveals a hidden Churg-Strauss syndrome

A 28 year-old caucasian lady, with nine years of uncontrolled bronchial asthma, rhinosinusitis and mild upper limb paresthesia, came to our attention to be followed for coeliac disease (CD). She had a biopsy performed elsewhere which proved the diagnosis five years before. Since there was no clinical improvement on a strict gluten-free diet, we re-evaluated the slides of her duodenal biopsies and we found an overestimation of the duodenal lesions due to the wrong orientation of the specimens. Moreover, she had never had positive CD-related antibodies and she was negative for DQ2/DQ8 MHC Class II heterodimers. Months later, she referred she was suffering from diffuse joint pain, epistaxis and a substantial weight loss. A few days later she was hospitalized because of a sudden onset of dyspnea, peripheral edema and pleural effusion. Her echocardiogram showed global left ventricular hypokenesia with an ejection fraction of 24%. The patient was discharged with a diagnosis of dilated cardiomyopathy and NYHA Class II. After a large spectrum of haematological exams, the diagnosis of Churg Strauss Syndrome (CSS), a rare multisystemic small-vessel necrotizing vasculitis, was confirmed by the presence of four/five out of six diagnostic American College of Rheumatology classification criteria (Asthma, Eosinophilia >10%, Neuropathy, Non-fixed pulmonary infiltrates, Paranasal sinus abnormality and Biopsy containing a blood vessel with extravascular eosinophils). Our patient had been under-diagnosed by pulmonologist and by gastroenterologists although she presented the criteria required for CSS diagnosis. Our case report emphasizes that often seemingly unrelated symptoms can be caused by a single rare clinical complex.

Esophageal Eosinophilia

The presence of esophageal eosinophilia encompasses a broad differential diagnosis, and at times a specific histologic diagnosis is not possible. This content provides a systematic approach to esophageal squamous eosinophilia with emphasis on specific, distinguishing features within this expansive differential.

Churg-Strauss syndrome: evidence for disease subtypes?

PURPOSE OF REVIEW

Churg-Strauss syndrome (CSS) is a rare systemic small-vessel necrotizing vasculitis. Its main clinical characteristics, some potentially life-threatening, are now well known, as are its usual successive phases, from allergic rhinitis to asthma, and finally vasculitis. Conversely, physiopathogenetic mechanisms are not completely elucidated and clearly multiple, thereby suggesting the existence of different disease subtypes.

RECENT FINDINGS

Almost 40% of CSS patients have circulating antineutrophil cytoplasm autoantibodies (ANCAs), mostly directed against myeloperoxidase. ANCA-positive patients suffer more frequently from renal disease, peripheral nervous system involvement and/or alveolar hemorrhage, whereas frequent cardiac involvement, lung infiltrates and/or systemic manifestations are more common in those who are ANCA-negative. However, their respective global outcomes do not clearly differ. Patients might also be categorized according to other, more subtle clinical, radiological and/or biological parameters, for example, cardiac magnetic resonance imaging abnormalities or genetic background.

SUMMARY

Because of its practical and therapeutic repercussions, the priority remains the prompt, relatively easy identification of the most severely affected patients at CSS diagnosis, before searching for and trying to classify subsets. Large, collaborative studies are needed to determine whether other subgroups might be associated with outcomes and warrant different, and possibly new, therapeutic strategies.

[New pathogenetic aspects in primary systemic vasculitides]

Primary systemic vasculitides are defined according immunopathological features and the size of the involved vessels. Three anti-neutrophil cytoplasmic autoantibody (ANCA) associated small vessel vasculitides (Wegener's granulomatosis, Churg-Strauss syndrome, microscopic polyangiitis) can be distinguished from the so-called Non-ANCA-associated vasculitides, i.e. granulomatous vasculitides of large vessels (giant cell arteritis, Takayasu arteritis) and immune complex-mediated vasculitides of medium-sized and small vessels (Polyarteriitis nodosa, Kawasaki disease and Henoch-Schönlein purpura, cryoglobulinemic vasculitis, cutaneous leukocytoklastische angiitis). Predisposing genetic and other endogenous and exogenous factors facilitate the activation of innate immunity and induce persisting inflammatory reactions resulting in different forms of (auto)-immune vasculitides.