ICP: From Correlation to Causation.

Intracranial pressure (ICP) is a complex modality in the sense that it largely interconnects various systemic and intra-cranial variables such as cerebral blood flow and volume, cerebrospinal fluid flow and absoption, craniospinal container. In this context, although empirical correlation is an interesting tool for establishing relations between pairs of observed variables, it may be limited to establishing causation relations. For instance, if variables X and Y are mainly influenced by variable Z, their correlation is strong, but does not mean that X has a causation relation with Y or vice versa. In this work, we explore the use of the statistical concept of partial correlation to ICP and other derived measures to apprehend the interplay between correlation and causation.

Frequency of irritable bowel syndrome in spondyloarthritis: a multicentric cross-sectional study and meta-analysis.

OBJECTIVE: To evaluate the prevalence of symptoms and factors associated with irritable bowel syndrome (IBS) in axial spondyloarthritis (ax-SpA). METHODS: In a cross-sectional multicentric study, consecutive patients with ax-SpA treated with biologics in five rheumatology departments were asked for IBS Rome IV criteria. Demographic data, lifestyle behaviours and disease characteristics were recorded. Second, a systematic literature review and meta-analysis were performed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. RESULTS: Of the 500 patients with ax-SpA included, 124 reported IBS symptoms (25%). Female gender, unemployment, higher Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and worse Bath Ankylosing Spondylitis Functional Index scores, multiple lines of biologics, fibromyalgia, anxiety, depression and lower physical activity were associated with IBS symptoms. In multivariate model, the risk of IBS was associated with anxiety and physical inactivity. From the literature review, the prevalence of IBS in patients with SpA was 15.4% (8.8% to 23.3%). Meta-analysis of the five studies comparing the presence of IBS in patients with SpA (323/7292) and healthy controls (484/35587) showed a significant increase of IBS in patients with SpA (OR=1.59 (1.05 to 2.40)). CONCLUSION: The prevalence of IBS symptoms was high in the ax-SpA population and should therefore be considered in the presence of gastrointestinal disorders. The presence of IBS symptoms was associated with anxiety and low physical activity in multivariate analysis. Patients with IBS symptoms tended to have more difficult to manage disease characterised by higher activity, worse functional score and multiple lines of treatment in univariate analysis.

Postpartum clostridial gangrenous metritis in 12 dairy goats in France.

Clostridial infections in goats have been associated frequently with enteric diseases or gas gangrene but very rarely with the reproductive system. We describe here 12 cases of fatal postpartum gangrenous metritis in does associated with infection by several clostridial species. Clinically, these cases were characterized by rapid onset of hyperthermia followed by death after kidding. On postmortem examination, the uteri appeared to be necrotic and were hemorrhagic and edematous. Microscopically, the uteri had diffuse coagulative necrosis, edema, hemorrhage, and fibrinous thrombi with intralesional gram-positive rods. Clostridium perfringens was isolated from 7 of 9 uterine samples cultured, and C. perfringens, C. septicum, C. novyi, or C. chauvoei were demonstrated by immunohistochemistry (IHC) in the 5 cases examined. IHC for Paeniclostridium sordellii was negative in all 5 cases. PCR performed on 3 of the C. perfringens isolates was positive for alpha toxin and perfringolysin, identifying these isolates as type A. Clostridial infection should be considered in cases of postpartum gangrenous metritis of does.

Tuberculoid nodular thelitis in a dairy goat flock.

An unusual outbreak of teat/udder skin lesions occurred in a dairy goat flock in France. Lesions first appeared as circular, indurated, erythematous areas of skin and progressed to form dark raised haemorrhagic crusts and ulcerative plaques. Histopathological examination revealed marked granulomatous dermatitis with multifocal ulceration. The granulomatous inflammation, with frequent Langhans type multinucleated cells and central caseous necrosis, was indicative of mycobacterial infection. The presence of non-cultivable mycobacteria was confirmed by sequencing PCR products from DNA extracted directly from the lesions and sequences matched a novel mycobacterial pathogen closely related to M. leprae and M. lepromatosis and previously identified in cattle thelitis. The association of nodular gross lesions and tuberculoid granulomas on the teat and lower udder, and the presence of mycobacteria DNA support a diagnosis of tuberculoid nodular thelitis in goats due to mycobacterial infection.