P064 Association Between Crohn's Disease (CD) and Transient IgM and IgG Immunodeficiency—Diagnostic and Management Challenges

CASE: Background: CD is an inflammatory disease that predominantly affects the gastrointestinal tract and has a progressive course. Immunodeficiencies can occur by altering different components of innate or adaptive immune responses. Such changes put the patient at greater risk for infectious diseases or non-infectious complications. Among the non-infectious complications are cancer, autoimmune diseases and gastrointestinal diseases, which should be suspected in patients with recurrent infections, with clinical, radiological or histological features of the disease are atypical or in the occurrence of an unsatisfactory response to conventional therapy. OBJECTIVE: To describe a case report of a CD patient complicated with enteric alterations related to immunodeficiency. RESULTS: A 31-year-old male patient started presenting abdominal pain, diarrhea, and weight loss in October 2020. He underwent a colonoscopy that showed diffuse involvement of the colon suggestive of CD. He didn`t respond to therapy with prednisone and azathioprine and lost 40kg until January 2021, when he was referred to an IBD center. He had signs of malnutrition (eg, BMI = 15.4, Albumin = 1.8g/dL). The MRI showed diffuse thickening of the walls of the entire length of the ileum, colon and rectum, associated with submucosal edema and more intense enhancement in the inner layer. Findings compatible with nonspecific diffuse ileocolitis. After negative infectious screening, hydrocortisone, azathioprine and infliximab were prescribed, but the patient remained clinical worsening. During the 6 weeks of therapy use, the patient presented oral candidiasis, septic pyoarthritis, DNA testing for Clostridium difficile and PCR for Cytomegalovius were positive. Despite the treatment of infectious diseases, the patient continued to worsen and was considered a primary non-response to anti-TNF, opting for the initiation of Ustekinumab. There was improvement in endoscopic and fecal calprotectin, but continued progression of ileal disease and diarrhea, with no response to enteral or parenteral nutritional therapies. An investigation for immunodeficiencies was carried out and IgM/IgG deficiency was noted, and parenteral immunoglobulin was started. He presented an intestinal subocclusion, requiring a loop ileostomy. In this surgery, it was decided to send a sample of ileal tissue for diagnostic differentiation, where ileitis was observed with intense plasma cell reaction and lymphoid nodular hyperplasia, uncharacteristic of DC, which may correspond to enteropathy secondary to immunodeficiency. Despite the treatment, the patient presented fungal endocarditis, esophageal moniliasis and septic condition of undetermined origin. He remained in hospital for 120 days until complete improvement of the infectious complications. With the slow improvement in nutritional parameters, there was a reduction in the incidence of infections as well as an increase in immunoglobulins. After five months of combined nutrition and anti-interleukin therapy, the patient presented clinical improvement, weight gain and complete normalization of IgG and IgM. Ileal disease is in regression and in the colon, in endoscopic remission. CONCLUSION: We present a case report of the initial presentation of DC complicated with severe malnutrition where there was depletion of part of immunoglobulins, resulting in infectious and non-infectious complications, where ileal involvement intensified the manifestation of colonic DC.