Case Report: Unexpected Benefit of Echocardiography in Childhood Polyarteritis Nodosa

Introduction

Polyarteritis nodosa (PAN) is a necrotizing vasculitis of unknown etiology affecting small and medium-sized arteries. Its clinical course may range from a benign cutaneous form to a life-threatening systemic form. The latter may represent a significant challenge to clinicians due to its rarity with only one child diagnosed with PAN during a 3-year study period in the Czech Republic (Dolezalova P et al., J Rheumatol 2004; 31: 2295–2299) and its variable manifestations mimicking bacterial infections, other more common chronic inflammatory diseases or even an acute abdomen. The most frequent presenting clinical features include fever, myalgia, skin, renal, gastrointestinal and neurologic involvement ([Table 1], Ozen S et al., Ann Rheum Dis 2010; 69: 798–806). Early recognition and treatment based on corticosteroids and cyclophosphamide is crucial for a good outcome.

Table 1 Classification criteria for childhood PAN (mandatory either of the major criteria and at least one of the minor criteria).

Major criteria	Minor criteria
Histopathological necrotising vasculitis	Skin involvement (livedo reticularis, subcutaneous nodules, skin infarctions)
Angiography (aneurysm or stenosis in small or medium-sized blood vessels)	Muscle involvement (myalgia or muscle tenderness)
	Arterial hypertension (more than 95. percentile)
	Peripheral sensory neuropathy
	Renal involvement (hematuria, proteinuria)

This case report may help to increase awareness of this very rare but potentially life-threatening disease among health professionals. Even though our patient finally exhibited numerous typical features of systemic PAN, there were two interesting aspects of this case. Firstly, the girl developed cerebral symptoms probably related to the syndrome of inadequate ADH secretion (SIADH) or posterior reversible encephalopathy syndrome (PRES). These presentations are not commonly reported in PAN when compared to more typical neurologic manifestations including peripheral neuropathy, cranial nerve palsy, cerebral infarction or meningitis/encephalitis (Eleftheriou D et al., Arthritis Rheum 2013; 65: 2476–2485). Secondly, this case emphasizes the role of echocardiography that provided us with a valuable clue leading to the diagnosis of a medium-sized vasculitis.