Reactive Arthritis - A Rare Complication of Intravesical BCG Instillation.

Reactive arthritis (ReA) with the classic triad of arthritis, conjunctivitis and urethritis, previously termed Reiter's syndrome, is a systemic illness, usually induced by genitourinary or gastrointestinal infections. However, it can be a rare complication of intravesical Bacillus Calmette-Guérin instillation (iBCG), a therapy prepared from attenuated strains of Mycobacterium bovis, a common and effective treatment for carcinoma in situ of the bladder (CisB). We report a case of a patient with CisB who developed ReA after iBCG. The symptoms resolved completely with corticosteroids. iBCG was stopped with no recurrence of carcinoma within 2 years. LEARNING POINTS: ReA is an aseptic arthritis, usually triggered by genitourinary or gastrointestinal infections, generally in individuals positive for HLA-B27.Septic arthritis and microcrystalline arthritis can mimic ReA and they must be ruled out with arthrocentesis.ReA may be considered as a complication in patients under iBCG.

Occam's razor versus Hickam's dictum: two very rare tumours in one single patient.

Occam's razor, the principle that a single explanation is the most likely in medicine, assumes that when a patient has multiple symptoms the clinician seeks a single diagnosis rather than diagnosing multiple and different ones. However, as proposed by Hickam's dictum, sometimes rare different diseases occurred in only one patient. We present a patient with a simultaneous diagnosis of two rare tumours, a cardiac hemangioma (primary cardiac tumour, often misdiagnosed as myxoma) and an appendiceal mucocele (a lesion of the appendix that can be neoplastic or not). A 71-year-old male presented with anorexia, asthenia, fever and weight loss for about one month. During the etiological investigation, a cardiac mass and an appendiceal lesion were detected and both lesions required surgical intervention. Cardiac and abdominal surgeries were uneventful and full recovery was achieved. The histological examination showed a cardiac hemangioma and a neoplastic appendiceal mucocele.

A test of the hierarchical model of litter decomposition.

Our basic understanding of plant litter decomposition informs the assumptions underlying widely applied soil biogeochemical models, including those embedded in Earth system models. Confidence in projected carbon cycle-climate feedbacks therefore depends on accurate knowledge about the controls regulating the rate at which plant biomass is decomposed into products such as CO2. Here we test underlying assumptions of the dominant conceptual model of litter decomposition. The model posits that a primary control on the rate of decomposition at regional to global scales is climate (temperature and moisture), with the controlling effects of decomposers negligible at such broad spatial scales. Using a regional-scale litter decomposition experiment at six sites spanning from northern Sweden to southern France-and capturing both within and among site variation in putative controls-we find that contrary to predictions from the hierarchical model, decomposer (microbial) biomass strongly regulates decomposition at regional scales. Furthermore, the size of the microbial biomass dictates the absolute change in decomposition rates with changing climate variables. Our findings suggest the need for revision of the hierarchical model, with decomposers acting as both local- and broad-scale controls on litter decomposition rates, necessitating their explicit consideration in global biogeochemical models.