Guideline on the clinical management of Henoch Schonlein Purpura (HSP)

Transcription

1 Guideline on the clinical management of Henoch Schonlein Purpura (HSP) Purpose To ensure a standardised approach in the management of children with HSP in southern Derbyshire. Scope The scope of this guideline is to provide an overview of features of HSP, and management of uncomplicated HSP. Introduction HSP is the most common vasculitis in childhood and affects the small vessels. Its course is often self-limiting although may manifest long-term renal morbidity. HSP can affect all age groups but most commonly children between 2 and 6 years of age. The incidence in children is reported as between 10.5 and 20.4/100,000 children per year. The latter is from a comprehensive study in the UK with information collected from primary and secondary care. The incidence was highest in the 4 6-year age group, with up to 70.3/100,000 per annum. There is a slight male preponderance of 1.2:1, with a lower incidence in black children compared with white or Asian. Aetiology The pathogenesis of HSP is not yet clearly understood, although it is known to be an immune complex-mediated disease. Preceding upper respiratory tract infections are common particularly with group A β-haemolytic streptococcus, but many other organisms have been implicated such as mycoplasma, adenovirus, parvovirus B19, varicella and herpes simplex. It is possible that there is a genetic predisposition to developing HSP and subsequent renal involvement. Diagnosis of HSP (EULAR/PReS consensus criteria 2006) Palpable purpura (essential) in the presence of one of the following: Diffuse abdominal pain Any biopsy showing predominant IgA Acute arthritis/arthralgia Renal involvement defined as any haematuria or proteinuria. All suspected cases in primary care should be discussed with CED consultants ( ), as depending on clinical presentation they may need prompt hospital review to confirm the diagnosis of HSP and exclude alternative conditions. In well children it may be more appropriate for them to be seen in rapid access clinic. Page 1 of 9

2 Table 1 Clinical features associated with Henoch Schonlein purpura Organ Involvement Incidence Description Skin 100% Essential for diagnosis. Initially, it may resemble an urticarial or erythematous macular-papular rash before developing into a palpable purpura, symmetrically distributed over the extensor surfaces of the lower legs, buttocks and arms. Lesions may spread to trunk and face. Bullous lesions may develop. Rash fades within weeks. Joints Up to 80% Usually an oligoarthritis. Mainly affects lower limb joints particularly ankles or knees. Self-resolving. Gastrointestinal 50-75% May be limited to mild colicky abdominal pain and/or vomiting, but in some cases abdominal pain can be severely debilitating. Some form of bleeding is common although massive haemorrhage only occurs occasionally. Intussusception is a well-recognised but rare complication. Pancreatitis, hydrops of the gallbladder and protein-losing enteropathy are also recognised, but rare features. Renal 20-60% Most common features are isolated microscopic haematuria with or without proteinuria. Macroscopic haematuria also common. Hypertension - may be isolated or related to renal involvement Acute nephritis or nephrotic syndrome or a mixed picture (6 7% of children with HSP). Acute renal failure - 91% of those who develop renal complications do so within 6 weeks and 97% within 6 months. Urogenital Up to 27% boys Usually manifests as orchitis. However, may mimic torsion and require surgical exploration to differentiate. There are single case reports in the literature of ureteral (often bilateral) stenosis associated with HSP. Neurological 2% Seizures, intracranial haemorrhage and cerebral vasculitis are reported but rare Headache is common but may not be recognised as a separate phenomenon. Pulmonary <1% Rare especially in children Clinically may present as an interstitial pneumonia with histology normally showing diffuse alveolar haemorrhage. Page 2 of 9

3 All patients need a thorough history and clinical assessment. The following differential diagnosis are to be considered: A. sepsis B. systemic vasculitides Wegener s systemic lupus erythematosus hypersensitivity vasculitis polyarteritis nodosa Initial Investigations All patients Weight & Height Blood Pressure (BP) Urine dipstick Consider the following if there is a diagnostic uncertainty Bloods - FBC and clotting screen, UE, CRP and blood culture ASOT titres and Anti DNAse B titres Complements (C3, C4) Auto antibodies Renal ultrasound (if significant renal impairment present) Management - Please also refer to appendix 1 below Clinical course: HSP is usually self-limiting (most remit within 6 weeks). A small minority may relapse. Long term morbidity is related to renal involvement. If the kidneys are involved, this usually manifests within 3 months from the date of onset but can present up to 12 months later. Admit to ward if: Severe symptoms of joint pain - restricting mobility despite adequate analgesia Severe abdominal pain or any signs or symptoms of bowel obstruction or GI haemorrhage Neurological symptoms Abnormal renal function Otherwise patients can be discharged home from CED with safety advice and information leaflet. Page 3 of 9

4 Appendix 1 - Initial management of Children with HSP Thorough history & clinical assessment Weight, BP, urine dipstick Admit to CED. Rule out other causes including sepsis. Consider bloods - FBC, clotting, U&E, CRP, blood culture, complement, ASO. titres and autoantibodies NO Clinically diagnosis of HSP certain YES Discuss with CED Consultant ( ) to decide when to be seen (same day, or rapid access clinic). Joint pain and Abdominal paincontrollable Normal BP Urine dipstick - equal to or less than 2+protein/blood Admit via CED if severe arthralgia (not responding to analgesia) Severe abdominal pain Evidence of bowel obstruction/gi haemorrhage Abnormal UE/macroscopic haematuria /Hypertension Any clinical concerns Home Supportive management Parent/Patient Education Paediatricians to discuss with Nephrologists if: Hypertension - confirmed Abnormal renal function Arrange appropriate follow up Macroscopic Haematuria - 5 days Nephrotic Syndrome: UP:UC> 250mg/mmol; Plasma Albumin < 25g/l; oedema Acute nephritic syndrome : Haematuria/ proteinuria/ oedema, hypertension/ oliguria Or, Persistent proteinuria: Note: UP:UC - urine protein creatinine ratio Page 4 of 9 UP:UC >250mg/mmol for 4 weeks UP:UC >100mg/mmol for 3 months UP:UC >50mg/mmol for 6 months

5 Appendix 2 Week 1 Hospital Review (Hot clinic or Obs unit review) Week 4 & week 12 GP review Week 8 Hospital Review (Hot clinic or / Outpatient clinic) 6 & 12 months GP review No renal involvement at 12 months Discharge no further review At any point Hypertension, significant proteinuria or macroscopic haematuria Microscopic haematuria No renal involvement at 24 months REFER TO PAEDIATRICIAN (Dr Bowker) Persistent microscopic haematuria 24 months GP review Note: Hypertension: Refer to BP centile charts (see Attachment 1) Significant proteinuria: 2+ in urine dipstick Macroscopic haematuria: visible or 3+ on dipstick Microscopic hematuria: urine dipstick 1 + for blood Page 5 of 9

6 Attachment 1 Use correct BP cuff size (as specified in the letter from hospital). Page 6 of 9

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