On day 12, during treatment with methylprednisolone and cyclophosphamide, she developed nausea, vomiting, headache, dizziness and convulsions. She had a clonic seizure in her hands for 20-30 seconds, developed incontinence and agitation, and gradually developed unconsciousness. She did not have any improvement after symptomatic treatment, and as per her guardian’s request, the patient was discharged and transferred to another hospital for further treatment (no details available). Neuroimaging findings are described in Table I. Convulsions, intellectual disability and inability to function independently were present 6.5 years after disease onset.

TABLE I Laboratory Features in Three Patients with Henoch-Schönlein Purpura-associated Encephalopathy

The blood　abnormalities and elevated creatinine (up to 175.6 ìmol/L) normalized after 22 days. Urine protein became negative after 3 months; however, microscopic hematuria remained present for a year and then resolved.

A 10-year-and-8-month-old Chinese boy had recurrent abdominal pain and vomiting for 10 days. One day before admission, he had a generalized seizure. On the 2nd day, there was blood in the stool and a dark red rash scattered throughout his lower extremities. Gastroscopy revealed features of HSP with gastrointestinal involvement and Helicobacter pylori (Hp) infection. According to the classification criteria for HSP by EULAR/PReS [7], this patient was diagnosed as HSP. He received multiple doses of intravenous methylprednisolone. During course of stay in hospital, he developed sudden-onset slurred speech and upper right extremity numbness, while maintaining consciousness. The results of craniocerebral MRI are described in Table I. On the 18th day, the child could walk steadily, and he was discharged. On follow-up, he did not develop any pain, seizures or any other neurological sequelae.

HSP-associated encephalopathy, including cerebral infarction, cerebral hemorrhage and degenerative white matter brain disease, is rare. To be diagnosed with HSP-associated encephalopathy, the patient should present with a typical palpable rash and clinical manifestations of CNS damage, while excluding systemic lupus erythematosus, and other connective tissue diseases, metabolic diseases and neurological diseases, such as intracranial infections. Cerebral MRI/CT scanning, particularly MRI, would be useful for detecting abnormal images in the brain [7].

The pathogenesis of HSP-associated encephalo-pathy is not fully understood. As vasculitides affects small blood vessels in the brain, damage to the endothelial cells and micro-thrombosis may occur. Hypoxic-ischemic brain injury induces cytotoxic cerebral edema, and the same time vasculitides increases vascular permeability, leading to cerebral hemorrhage. Murakam, et al. [8] reported brain biopsy finding from a fatal case of HSP, and demonstrated leukocytoclastic vasculitides on light microscopy. A perivascular inflammatory cell infiltrate was evident in the small vessels, and there were IgA deposits in the vessel wall. Few cases of posterior reversible encephalopathy syndrome (PRES) have also been described in HSP.

HSP is usually self-limited in children, and treatment remains controversial. With evidence of more complicated course and irreversible sequelae that can result from encephalopathy, aggressive treatment may be indicated. Currently, pulse methylprednisolone therapy is most commonly used for HSP encephalopathy [9]. Plasmapheresis has been recommended for patients not responding to methylprednisolone.

Contributions: HJS, JHM: participated in manuscript drafting and the clinical diagnosis of the patient; QS, LZD: participated in data collection, imaging studies and manuscript drafting.

Funding: National Natural Science Foundation of China (Grant Nos. 81470939, 81270792 and 81170664), State "1025" Science and Technology Support Projects (2012BAI03B02), the Research Fund for the Doctoral Program of Higher Education of China (20120101110018), the Zhejiang Provincial Healthy Science Foundation of China (WKJ2010-2-014, 2012KYA119), the Zhejiang Provincial Program for the Cultivation of High-Level Innovative Health Talents and the Zhejiang Provincial Natural Science Foundation of China (LY12H050037), the Zhejiang Provincial　Administration of 　Traditional Chinese Medicine of China (2009CB049), the Zhejiang Provincial Department of Education Foundation of　　 China　(Y200804449).

Competing interest: None stated.

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