We report a 41-year-old Chinese male patient who went to the Department of Gastroenterology, Shanghai Tenth People’s Hospital for treatment. He suffered from skin lesions and diarrhea for more than 3 years, perianal abscess and bloody stool for 2 years, and exacerbation of abdominal pain for 1 year. The patient had a 25-year history of smoking and didn’t have a family history of CD, however, his grandfather, father, and cousin also had psoriasis. Tracing back the medical history, the patient developed erythema and desquamation on the trunk and limbs from the summer of 2016. He was diagnosed as psoriasis at the Department of Dermatology of Shanghai Huashan Hospital. Using oral silver-removing granules (traditional Chinese medicine) and topical calcipotriol cream did not improve the skin lesions efficiently. The symptoms of patient included the diarrhea as well as increased frequency of defecation. Given no obvious abdominal pain, pus and blood, he did not see a doctor. By the beginning of 2017, the patient felt perianal discomfort, and there was hematochezia and the yellow sticky discharge, which was diagnosed as perianal abscess at Anorectal Surgery, Shanghai Shuguang Hospital, where the patient was given symptomatic treatment. After that, the patient’s perianal abscess improved, but there was still blood in the stool.
He was performed medical exams in May 17, 2017, and the colonoscopy showed scattered aphthous ulcers in the terminal ileum (Fig. 1a), ileocecal region (Fig. 1b) and descending colon (Fig. 1c) before the use of IL-17 inhibitors. A pathology of his ileocecal junction indicated chronic active inflammation of the mucosa (Fig. 2a).
In June 2017, the patient’s skin lesions worsened, and he returned to Shanghai Huashan Hospital to use IL-17 inhibitor secukinumab, 0.3 g per week for 4 weeks, and then 0.3 g per month, a total of 8 months.
In July 2017, 1 month after the application of secukinumab, the skin lesions significantly improved, but mucopurulent bloody stool appeared, about 5 times per day, with obvious pain in mid-lower abdomen, which eased slightly after defecation.
From August 2017 to March 2018, the patient used the IL-17 inhibitor. During this period, the patient used 0.045 g of ustekinumab (IL-12 / 23 inhibitor) once, and the skin lesions did not improve.
From April to June 2018, the patient received ixekizumab (IL-17A antagonist), 0.08 g per month.
In July 2018, the patient’s skin lesions healed, but the intestinal symptoms worsened, so he went to the Department of Gastroenterology, Shanghai Tenth People’s Hospital, where laboratory investigations were significant for an elevated Creactive protein (CRP) of 0.0765 g/L and the reduced Hemoglobin (HB) of 120 g/L.
After the use of IL-17 inhibitors, the colonoscopy showed longitudinal ulcer and multi-segment ulcers in the distal ileum and colorectum, congestion and edema in the surrounding mucosa, and paving stone-like changes (Fig. 1d, e, f) at locations similar to Fig. 1a, b, c, respectively.
The intestine CT demonstrated that the jejunum, ileum, ileocecal junction (Fig. 3a, left arrow), ascending colon (Fig. 3b), transverse colon, descending colon (Fig. 3a, right arrow), and sigmoid colon (Fig. 3c) have a long range of intestinal wall thickening to varying degrees, poor filling and expansion, and mild intestinal lumen narrowing. Correspondingly, mesentery-side vessels around the intestinal loop proliferated, dilated, and twisted. Small straight vessels expanded to form the comb-like shape (Fig. 3d). There were multiple small lymph nodes around some mesentery vessels. Therefore, he was diagnosed with Crohn’s disease in active phase.
The pathology of colon revealed the hyperemia and erosion of the mucosa, infiltration of moderate lymphocytes, plasma cells and a small amount of eosinophils and neutrophils in the lamina propria, hyperplasia of lymphoid tissue in the submucosa, suspicious granulomas and suspicious fissure ulcer (Fig. 2b).
Immunohistochemical staining showed moderate intensity staining of inflammatory cells in the lamina propria, and the glandular epithelium of the crypts was weakly expressed before the use of IL-17 inhibitors (Fig. 2c). After the use of IL-17 inhibitors the immunohistochemical staining also showed moderate intensity staining of inflammatory cells in the lamina propria, but the glandular epithelium of the crypts was widely expressed.
The physical exams showed extensive dark brown patches of skin. Scattered patches of erythema and desquamation was on the limbs and trunk. Perianal swelling and a little purulent discharge could be seen. He had lost 10 kg of weight since his illness. From July 25, 2018, the patient took an oral immunosuppressant: azathioprine 0.05 g daily, and felt unwell. From September 10, 2018, he reduced it to 0.025 g daily, and stopped using it on October 30, 2018.
In 2018-7-31, 8–13, 9–10, 10–30, 12–14, and 2019-02-15, the patient was treated with Infliximab 0.4 g 6 times totally.
After the first treatment with infliximab, the purulent stool and abdominal pain disappeared, and there was no perianal exudation.
After the four times use of infliximab, the patients gradually appeared joint pain and increased skin lesions. It was suggested to continue to use infliximab after consultation with dermatology department, but the symptoms of joints and skin lesions were not relieved. The patient was worried. Infliximab was stopped after 6 times of use.
From April 3, 2019, the patient was treated with Tremfya (guselkumab, IL-23 inhibitor) 0.1 g per piece at week 0,4, and then every 8 weeks, maintained until December 9, 2019 for a total of 6 times. After the second treatment with guselkumab, the rash disappeared and the joint pain disappeared. During this period, the patient had no intestinal symptom, so he was satisfied with his quality of life.
In September 2019, the patient was re-examined. The serum IL-17A was 6.73 pg/ml. The colonoscopy showed that the previous longitudinal ulcers healed and polyp-like hyperplasia was seen, which was considered as Crohn’s disease in remission following anti-TNF and IL-23 inhibitor therapy (Fig. 1g, h, i).