Henoch Schonlein Purpura in Children: Clinical Analysis of 120 Cases

Background: Henoch Schonlein Purpura (HSP) is a systemic vasculitic disease which is common in children. It is very important to understand the clinical features of this disease for doctors and nurses. Objectives: To study the clinical characteristics of HSP in children. Methods: Collect the clinical data of the HSP children, and analyze the clinical characteristics of these HSP patients. Results: The ratio of M:F was 1.9:1. The mean age was 6.6 ± 1.6 years. The typical onset seasons were spring, winter and autumn. Infection and food allergy were the main etiological factors. The first symptom was skin purpura and these purpura mainly concentrated the lower extremities and buttocks. The dominant digestive clinical features were abdominal pains and vomiting. The knee joint and ankle joint were most frequently affected. The typical kidney symptoms were microscopic hematuria and albuminuria. An increased ESR was reported in 68 patients (56.7%). Serum C3 decreased in 13 cases (10.8%). ASO titer was higher in 57 children (47.5%). Conclusion: There were gender, season and area differences for the HSP patients. The etiological factors were diverse. HSP patients could have various clinical symptoms and rare complications.


Introduction
Henoch Schonlein Purpura(HSP), was first recognized in 1801 by Heberden and first described as an association arthritis by Schonlein in 1837. 1 It is a systematic vasculitic disease, and mainly affects the small vessels of skin, joints, gastrointestinal tract, and kidneys.7][8] The pathogenesis also remains unknown.At present, HSP is regarded as an inflammation and immune-mediated disease. 9IgA and some proinflammatory cytokines have the pivotal role in the pathogenesis of HSP. 10 The typical clinical characteristics involve the triad of palpable purpura, abdominal pain and arthritis.Progressive renal function impairment, bowel perforation, central nerve system involvement are rare.The occurrence of purpura, which are nonthrombocytopenic, is the essential element for the diagnosis of HSP.The purpura are often located on some parts just as lower extremities and buttocks. 10HSP, in general, is considered benign and self-limited and the treatment is supportive.
The aim of our study is to analyze the clinical data of the HSP children, and discuss the clinical characteristics of HSP in children.We think knowing about the clinical features could help doctors to make the correct diagnosis and provide the correct remedy and nursing.

Methods
This is a retrospective study.The patients were HSP children treated from the Qilu Hospital, between 2007 and 2010.We selected the patients who accepted the whole remedy in the pediatric bed-ward of Qilu Hospital.Those patients who left the hospital before improvement and recovery were excluded form our study.The diagnosis criteria were the American College of Rheumatology 1990 criteria for the classification of HSP 11 .Approval for this research was obtained from the Medical Ethic Committee of the Qilu Hospital.

Definition
The epidemiological data were analyzed: City means the settlements where the non-agricultural industries and non-agricultural population concentrate in.Countryside means the area where the agricultural production laborers inhabited in.Spring includes March, April and May.Summer means June, July and August.Autumn refers to September, October and November.Winter means December, January and February.Previous infection, special food, vaccination, insect bite, and accident were considered as the precipitating factors to be specially retrospectively looked, if they happened in 2 weeks before HSP onset.Preceding infection was self reported.
About the clinical characteristics, we defined as follows: Microscopic hematuria wasdefined when the test result was > +; Albuminuria was defined when the test result was > +; Gross hematuria was defined blood in the urine could be seen with the naked eye; Tubular urine was defined one more urinary cylinder were found per low power field.Rash location means purpura mainly concentrated in the parts of the body.

Statistical analysis
All data were described as means and standard deviations (mean ± SD) or medians and ranges.Categorical variables were expressed by percentages.

Epidemiological features
The main epidemiological data are shown in table 1.There were 120 children fulfilling the diagnosis criteria between January 2007 to December 2010.The 120 HSP children included 78(65%) boys and 42(35%) girls.Males were affected more than the females (Ratio M:F=1.9:1).The age range was from 1 to 12 years ( mean age 6.6 ± 1.6 years).The age and gender distribution showed that most HSP children ( 103 cases, 85.3%) were less than 8 years old, 88.3% were <10 years old, and 98 cases of HSP children (81.7%) were between 5 and 8 years old (figure 1).It was found that 40 cases (33.3%) occurred in spring, 12 cases (10%) in summer, 24 cases (20%) in autumn, and 44 cases (36.7%) in winter.The countryside patients were 73 cases (60.8%), while there were 47 city children (39.2%).For 98 cases, this was their primary presentation.There were 22 relapse patients.

Figure 1: Age and gender distribution of 120 HSP patients
The age range was from 1 to 12 years (mean age 6.6 ± 1.6 years).The age and gender distribution showed that most HSP children (98cases, 81.7%) were less than 8 years old, and 103 cases of the HSP children (85.3%) were part of the age range between 5 and 8 years old (figure 1).
Before HSP onset, there were 73 cases (60.8%) who had an infection, and among these patients, 52 children had an upper respiratory tract infection; 17 cases had bronchial pneumonia; 4 patients had enteritis.The results revealed 32 patients had eaten special food just as fish or shrimp before onset, and there were 2 children who had been given a measles-mumps-rubella vaccination 2 weeks before HSP onset, and 1 child who had been accepted a Hepatitis B vaccine 1 weeks before HSP coming.Parasite infection was reported in 3 patients (2.5%), and among these children, ascarids attacked 1 child, and the other two had been infected by threadworms.Tick bites were announced in 2 cases one week before disease onset.Two children had choked with water seriously during swimming before.There were unknown etiological factors in four children before disease onset.Microscopic hematuria was defined when the test result was > +; Albuminuria was defined when the test result was > +; Gross hematuria was defined blood in the urine could be seen with the naked eye; Tubular urine was defined one more urinary cylinder were found per low power field period.

Clinical features
The main clinical characteristics of the 120 HSP children were showed in table 2.

First symptom
The first symptoms were diverse.It was found that 83 cases (69.1%) displayed skin purpura alone, while 14 patients (11.7%) told abdominal pains.One child (0.8%) had joint pains, and purpura and joint pains were reported in 11 children (9.2%).We also found nine patients (7.5%) had purpura and abdominal pains meanwhile, and the joint pains, purpura and abdominal pains were complainted in 2 cases.

Purpura
All children appeared skin eruption.The purpura lesions of most patients were concentrated on the lower extremities and buttocks.

Uncommon clinical features
The results showed calf swelling in 5 cases (4.2%), orchitis in 2 children (1.7%).We also found 3 HSP cases had pneumonia during they accepted the remedy.

Laboratory findings
The main laboratory data of the acute phase were showed in Table 3.An increased ESR was reported in 68 patients (56.7%).Serum C3 decreased in 13 cases (10.8%).ASO titer was higher in 57 children (47.5%).

Treatment
The main resolved drug included the glucocorticoid, immunosuppressor, antihistamine drug, calcium channel blocker drug.

Outcome
There were 89 patients (74.2%) had been cured, and the conditions of 31 children of HSP (25.8%) improved.

Discussion
HSP which is characterized by a purpuric rash, arthritis, nephritis and gastrointestinal symptoms is a systemic vasculitis of unknown etiology. 9It is the most common childhood vaculitis, with an annual incidence of about 10 cases per 100,000. 2 HSP was announced in association with infections, medications, vaccination.The pathogenesis is poorly understood.It was reported an IgA-mediate disease. 10This multisystem disease mainly affected skin, kidneys, joints, gastrointestinal tract, and other organs still could be affected.It is considered nonfatal and self-limiting.Renal involvement could make the chronic consequences of HSP patients. 23][14][15] In our investigation, the patients ranged from 1 to 12 years.According to our study, HSP occurs most frequently between the age of 6 to 7 years old, 88.3% were <10 years old, only 3 cases were <2 years old , and the mean age was 6.6 ± 1.6 years.In our literature, 65% of the patients were boys and 35% were girls.The ratio of M:F was 1.9:1.According to the findings, the boys are affected more often than the girls, and this findings were in accord with Frank T Saulsbury's "Clinical update: Henoch-Schonlein Purpura". 2Gender distinction about the HSP incidence was also reported in other studies.In these investigations, HSP in children was more common in males. 3,14,16By contrast, female advantage was found in these studies. 4,17ccording to our results, the incident seasons were spring, winter and autumn.The lowest incidence was in summer.[15][17][18][19][20][21] The etiological factors are still unclear.Our reports showed that 73 patients (60.8%) experienced infection before HSP onset and 32 cases (26.7%) occurred food allergy.Infection and food allergy were the main etiological factors in our study.Children often experienced respiratory tract infections in the cold months, so the high incidence in cold months suggested the association between HSP with infection, and this conclusion was alike with some investigations. 3,14,22Some accounts had reported the trigger events including vaccinations, insect bites, and drugs have been connected with HSP. 23,24In the present investigation, infection, food allergy, vaccination, parasite infection, insect bite, and emergency all may be potential trigger events for HSP onset.Furthermore we could not find the relevant factors about HSP onset for some patients.
In this study, we found that the incidence of the countryside children had been higher than the patients from the city.One of the reasons leading to this result may be the different hygiene and environment between city and countryside.
In terms of our research, the first symptoms for the HSP children were different.A majority of the HSP patients displayed skin purpura alone at the onset.The purpura lesion concentrated the lower extremities and buttocks.The skin eruption of all patients faded during 2 to 40 days, and the averages were 9.14 ± 5.42 days.
We discovered many HSP children displayed the digestive system symptoms.The dominant digestive clinical features were abdominal pains and vomiting.Digestive complications just as haematemesis, intussusception and intestinal obstruction could also occur.Gastrointestinal involvement buffered during 1 to 30 days, and the averages were 4.15 ± 1.14 days.
Many HSP patients displayed the joint symptom.The knee joint and ankle joint were most frequently affected, and the results were same with Sandra and coworkers. 5In our study, the other joints just as wrist joint, elbow joint, metacarpophalangeal joint and hip joint were reported to be affected.
In our report, the typical kidney symptoms were microscopic hematuria and albuminuria.We also detected some cases occurred uncommon clinical features, just as calf swelling, orchitis and pneumonia.

Conclusion
We considered that there were gender difference, season difference and area difference for HSP children.The etiological factors were diverse.HSP patients could have various clinical symptoms and rare complications.Knowing well the diversiform clinical features of the HSP could help us to make the correct diagnosis and give the right cure and nursing.Although the epidemiology, clinical characterics, treatments, prognosis of HSP have been researched for many years, several questions still remain.Why do some children have the serious complication?Why do some children progress to end-stage renal disease?So we thought the investigation about the genetic susceptibility to HSP, immune pathogenesis, and more effective treatment still had been needed in this area.

Table 1 :
EpidemiologicalCity means the settlements where the non-agricultural industries and non-agricultural population concentrate in.Countryside means the area where the agricultural production laborers inhabited in period.Spring are March, April and May.Summer are June, July and August.Autumn are September, October and November.. Winter are December, January and February.

Table 2 :
Main clinical features of the 120 children with HSP

Table 3 :
Laboratory findings in 120 children of HSP