Churg-Strauss Syndrome: A Cause of Painful Neuropathy

Abstract & Commentary

By John J. Caronna, MD, Professor of Clinical Neurology, Weill Cornell Medical College. Dr. Caronna reports no financial relationships relevant to this field of study.

Synopsis: Churg-Strauss syndrome is an immune-mediated disorder that commonly affects the peripheral nervous system.

Source: Wolf J, et. al. Neurologic complications of Churg-Strauss Syndrome – A prospective monocentric study. Eur J. Neurol 2009; do1: 10.111/j. 1468-1331, 2009. 02902. Finsterer J. Editorial: Neurological manifestations of Churg-Strauss Syndrome. Eur J Neurol 2009; do1: 10.111/j. 1468-1331, 2009. 02903

Churg-strauss syndrome (CSS) was classified as a variant of polyarteritis nodosa (PAN) until 1951.1 Although it shares various clinical laboratory and pathological characteristics with both PAN and Wegener granulomatosis, a distinct combination of features identifies CSS as a separate entity. The distinctive features of CSS are adult onset asthma that precedes the occurrence of systemic vasculitis, and a peripheral and tissue eosinophilia. The neurologic abnormalities of CSS — mononeuritis multiplex and distal symmetric polyneuropathy — are similar to those in PAN.2

Wolf et al have reported a prospective study of 14 patients (7 men and 7 women) with CSS, 12 of whom presented with neurologic involvement. All the patients had a history of asthma and eosinophilia. Eosinophils were 21% to 85% of total leukocyte counts. All of the patients had severe multi-organ involvement by systemic vasculitis at the time of initial diagnosis. The mean age was 55 ± 14 years (range 34–75).

At presentation, ESR and CRP were elevated in 10 patients. Antineutrophil cytoplasmic antibodies (ANCA) were positive in four patients, with a perinuclear fluorescence pattern (p-ANCA) in three, and with a cytoplasmic pattern (c-ANCA) in one. The presence of ANCA was associated with higher values of CRP (p < 0.01).

All patients received a detailed neurologic examination and motor and sensory nerve conduction studies as well as needle EMGs. Of the 12 who presented with neurological involvement, eight had mononeuritis multiplex (sural, common and deep peroneal, posterior tibial, median, ulnar, radial, and lateral femoral cutaneous nerves), three had an axonal polyneuropathy, three had neuropathy of cranial nerves (facial palsy, anterior ischemic optic neuropathy), and two had cerebral infarcts in the basal ganglia. In one patient, muscle biopsy revealed myositis.

Severe neuropathic pain, present in eight of eleven patients with peripheral neuropathy, decreased with the initiation of immunosuppressive therapy despite the persistence of axonal neuropathy. Neurological involvement, primarily mononeuritis multiplex followed by symmetrical polyneuropathy and cranial neuropathy was frequent in CSS but the outcome was favorable if treatment was initiated early.

Commentary

CSS is increasingly recognized but remains an uncommon disease of unknown cause. ANCA probably play an important role in the pathological mechanism of disease. Asthma is the cardinal feature of CSS and presents long before the onset of systemic vasculitis. An eosinophilia of more than 10% on differential WBC count also precedes multisystem involvement. A vasculitis of small and medium-sized arteries, if untreated, leads to death because of damage to the lungs, kidneys, heart and other organs.1 Peripheral nervous system manifestations occur in up to 75% of patients with CSS, CNS involvement in less than 10%. In CSS, as in PAN and SLE, inflammation of central nervous system (CNS) vessels is less frequent than of visceral or peripheral nervous system arteries. CNS complications tend to occur later and are due to hypertension, vaso-occlusive changes in arteries or cardiac-origin emboli.

The study by Wolf and colleagues is a reminder that in patients with painful neuropathy and a history of asthma, sinusitis or stroke, one should consider CSS.

References

1. Churg J, et al. Cutaneous lesions of allergic granulomatosis: A histopathologic study. Am J Path 1951;27:277-301.

2. Moore PM, et al. Neurology of the vasculitides and connective tissue diseases. J Neurol Neurosurg Psychiatry 1998;65:10-22.