HSP is a commonly vasculitis in childhood. In this study, we retrospectively analyzed the clinical data of 10791 HSP children who attended our hospital between January 2014 and June 2018. Among the 10791 HSP children, 10194 cases (94.47%) occurring at the age of 3~14 years, 6168 cases (57.16%) occurring at the age of 5~9 years.
Gastrointestinal symptoms were frequently observed in children with HSP, accounting for 50%~75% [2, 3, 9], abdominal distention and abdominal pain are the usual clinical manifestations, and the pathological manifestations are erosion, edema and necrosis of gastrointestinal tract mucosa[10]. Typical endoscopic manifestations of HSP include diffuse mucosal edema, erythema and ecchymosis, or multiple irregular ulcers [11, 12]. In our study, we found 11 of the 10791 HSP children developed GP, with an incidence of 0.10%, lower than that reported in the literature of 0.38%[13]. To our knowledge, the reported 11 patients represent the biggest retrospective case series hitherto published.
GP is one of the abdominal complications requiring surgical treatment in HSP children. Other complications include intussusception, massive gastrointestinal bleeding and intestinal necrosis[14]. The symptoms of children with GP are relatively serious, and delayed treatment may endanger the life of the patients. Hence, we analyzed the possible risk factors of GP in HSP children, including age, gender, purpura type, the time of abdominal pain, hematochezia, renal damage, methylprednisolone dose more than 2mg/kg.
In our study, 7 HSP children with GP were associated with renal damage (63.63%), which was significantly higher than that of the control group (26.2%), suggesting that HSP children with renal damage had a greater risk of GP. Some studies indicate that abdominal pain may be one of the important risk factors of HSP children renal damage [5, 15], therefore, HSP children with gastrointestinal symptoms should be regularly monitored with routine urine, renal damage. 11 cases HSP children with GP all showed bloody symptoms (100%), while the control group only 3 cases (7.14%) showed bloody symptoms, indicated that bloody symptom is one risk of GP. In addition, HSP children with GP show a large number of skin purpura, and 3 cases show facial purpura. Whether the risk of GP can be identified early according to the severity of skin purpura and site symptoms remains to be further studied and confirmed.
The pathogenesis of GP in HSP children was still unclear. It has been reported that thrombus caused by vasculitis may lead to intestinal ischemia, followed by intestinal wall necrosis and perforation [16]. Ultrasonography or CT signs are useful to confirm the diagnosis of GP. The key to ultrasonographic examination of gastrointestinal perforation is the free gas under the diaphragm and a small amount of gas and fluid next to the perforation. When the perforation is small, the subphrenic gas is less, or the intestinal perforation is wrapped by other surrounding tissue, the gas can’t reach the subdiaphragm, or the patient has a large amount of air in the intestinal loop, it will affect the color ultrasound diagnosis. In our study, ultrasonography did not indicate perforation, but CT indicated perforation of gastrointestinal tract in 5 cases, suggesting that CT was more sensitive than ultrasonography. Therefore, when GP was not detected by ultrasonography but clinical symptoms can’t be excluded, we should perform CT examination to avoid misdiagnosis.
In our study, the average duration of abdominal pain of GP in HSP children was 9.3 days, this was consistent with that intestinal perforation of HSP occurred during the second week after hormone application[13]. There are 9 cases (81.8%) abdominal pain lasted more than a week, while the longest time in the control group is 5 days. HSP children abdominal pain lasting more than a week can be considered as identifying early GP reference. Glucocorticoid can reduce the edema, relieve pain, application of hormone in early stage may reduce the risk of surgical intervention[4, 15]. But systemic glucocorticoid therapy may mask symptoms of surgical complications such as abdominal pain and fever[15]. Some studies have shown that large doses of corticosteroids could reduce mucosal mucus synthesis in the gastrointestinal tract, inhibit the regeneration and healing of the intestinal mucosa, reduce the thickness of the gastrointestinal wall, and reduce lymphatic follicles, all of which increase the risk of intestinal perforation[5, 6, 13, 17]. Our study indicated that a course of methylprednisolone of more than 7 days and a dose of more than 2mg/kg were risk factors of GP in HSP children. However, hormones were still the most effective treatment options for abdominal symptoms of HSP. Therefore, in the clinical treatment of HSP patients, it is necessary to weigh the advantage and disadvantages of long-term and high-dose hormone use, and to control the dosage and course of hormone use.