A nearly fatal primary Epstein-Barr virus infection associated with low NK-cell counts in a patient receiving azathioprine: a case report and review of literature.

BACKGROUND: Symptomatic primary Epstein-Barr virus infection is a usually self-limiting illness in adolescents. We present a case of an adolescent who had been receiving azathioprine for inflammatory bowel disease for four years and developed a life-threatening primary Epstein-Barr virus infection successfully treated with rituximab. CASE PRESENTATION: An 11-year-old girl presented with chronic, bloody diarrhea. Endoscopic biopsies confirmed a diagnosis of chronic ulcerative colitis with features of Crohn's disease. Azathioprine was initiated after one year due to active colitis. She responded well and remission was achieved. At the age of 16 years she developed a life-threatening Epstein-Barr virus infection including severe multiple organ failure and was critically ill for 4 weeks in the intensive care unit. Natural killer cells were virtually absent in the lymphocyte subset analysis. Azathioprine was stopped on admission. She was initially treated with corticosteroids, acyclovir and intravenous immunoglobulin. Approximately 30 days after admission, she developed signs of severe hepatitis and pneumonitis and received weekly rituximab infusions for 8 weeks. Primary immunodeficiency was excluded by whole exome sequencing in two independent laboratories. Persistent viremia stopped when the natural killer cell count started to rise, approximately 90 days after the cessation of azathioprine. CONCLUSIONS: We found 17 comparable cases in the literature. None of the previous cases reported in the literature, who had been treated with azathioprine and developed either a severe or a fatal Epstein-Barr virus infection, underwent full genetic and prospective immunological workup to rule out known primary immunodeficiencies. Recently, azathioprine has been shown to cause rather specific immunosuppression, resulting in natural killer cell depletion. Our case demonstrates that slow recovery from azathioprine-induced natural killer cell depletion, 3 months after the stopping of azathioprine, coincided with the clearance of viremia and clinical recovery. Finally, our choice of treating the patient with rituximab, as previously used for patients with a severe immunosuppression and Epstein-Barr virus viremia, appeared to be successful in this case. We suggest testing for Epstein-Barr virus serology before starting azathioprine and measuring natural killer cell counts during the treatment to identify patients at risk of developing an unusually severe primary Epstein-Barr virus infection.

Wheat oral immunotherapy was moderately successful but was associated with very frequent adverse events in children aged 6-18 years.

AIM: This study investigated oral immunotherapy (OIT) for children aged 6-18 years with wheat allergies. METHODS: Well-cooked wheat spaghetti was given to 100 children with wheat allergies every day for 17 weeks, increasing from 0.3 to 2000 mg of wheat protein, followed by three- and nine-month maintenance phases. Blood samples were taken before therapy and at follow-up visits. The study was carried out in 2009-2015 in four Finnish paediatric allergology units. RESULTS: The children (67% male) had a mean age of 11.6 years (range 6.1-18.6), and 57 were using wheat daily 16 months after the initiation of therapy. Allergic symptoms occurred in 94/100 children: mild in 34, moderate in 36 and severe in 24. Specific immunoglobulin E (IgE) for ω-5-gliadin was significantly higher in patients who did not reach the target dose and were related to the intensity of reactions. CONCLUSION: The majority (57%) of children with wheat allergies could use wheat in their daily diet 16 months after the initiation of OIT, but 94/100 had adverse reactions and 60 were moderate or severe. Specific IgE to ω-5-gliadin may provide a biomarker for how much wheat can be tolerated and the intensity of the reactions to immunotherapy.

Lymphoid nodular hyperplasia and cow's milk hypersensitivity in children with chronic constipation.

OBJECTIVE: To investigate the incidence of cow's milk allergy as evidenced by milk challenge and the findings of endoscopic and immunohistochemical examinations in children with chronic and refractory constipation. STUDY DESIGN: Thirty-five study subjects (mean age, 8.3 +/- 3.3 years; range, 3-15 years; 17 girls) and 15 control subjects (mean age, 11.7 +/- 3.2 years; range, 2-15 years; 9 girls) were studied by colonoscopy and a 4-week cow's milk elimination and challenge. RESULTS: Lymphoid nodular hyperplasia was the most prominent endoscopic finding in half of the subjects (46%), mostly occurring patchily in the transverse colon. Histologic findings other than lymphoid accumulation and mildly increased density of eosinophils were few. During the milk elimination and with supportive medication, 83% of subjects remitted. Constipation and/or other gastrointestinal or skin symptoms relapsed only in one third (34%) during the cow's milk challenge, these having significantly higher densities of intraepithelial gammadelta + T cells ( P <.001) in the biopsy samples of the terminal ileum as compared with the control subjects. CONCLUSIONS: We were able to find formal evidence for the presence of cow's milk allergy in children with chronic constipation.