Intussusception of the appendix in a young adult: an important differential diagnosis of abdominal pain in cystic fibrosis patients?

Cystic fibrosis (CF) is commonly associated with gastrointestinal manifestations from infancy to adulthood. Distal intestinal obstruction syndrome (DIOS) affects 20% of CF patients, where intussusception can be a rare complication. A 20-year-old CF male was diagnosed with a 3-day history of right iliac fossa pain and diarrhoea. Clinical examination revealed a tender palpable mass in the right iliac fossa and raised serum inflammatory markers. Contrast computerized-tomography of the abdomen-pelvis suggested intussusception of the appendix and further confirmed on histological analyses. The patient underwent an open appendicectomy where the intussusception had self-resolved. The literature review indicated a scarcity of data with 10 cases reported of intussusception in adult CF patients. Our case was in line with previous research of transient intussusception. This rare case highlights an importance to carry a higher index of suspicion for gastrointestinal manifestations in CF patients where differential diagnoses of DIOS and intussusception should be considered in the acute presentation.

Interleukin-17-positive mast cells influence outcomes from BCG for patients with CIS: Data from a comprehensive characterisation of the immune microenvironment of urothelial bladder cancer.

The tumour immune microenvironment is considered to influence cancer behaviour and outcome. Using a panel of markers for innate and adaptive immune cells we set out to characterise and understand the bladder tumour microenvironment of 114 patients from a prospective multicentre cohort of newly-diagnosed bladder cancer patients, followed-up for 4.33±1.71 years. We found IL-17-positive cells were significantly increased in primary and concomitant carcinoma in situ (CIS), p<0.0001, a highly malignant lesion which is the most significant single risk factor for disease progression. Further characterisation of the tumour immunophenotype identified IL-17+ cells as predominantly mast cells rather than T-cells, in contrast to most other tumour types. Expression of the IL-17-receptor in bladder tumours, and functional effects and gene expression changes induced by IL-17 in bladder tumour cells in vitro suggest a role in tumour behaviour. Finally, we assessed the effects of IL-17 in the context of patient outcome, following intravesical BCG immunotherapy which is the standard of care; higher numbers of IL-17+ cells were associated with improved event-free survival (p = 0.0449, HR 0.2918, 95% CI 0.08762-0.9721) in patients with primary and concomitant CIS (n = 41), we propose a model of IL-17+ Mast cells mechanism of action. Thus, in the context of bladder CIS, IL-17+ mast cells predict favourable outcome following BCG immunotherapy indicative of a novel mechanism of BCG immunotherapy in UBC and could form the basis of a stratified approach to treatment.