Prevalence and predictors of severe Crohn's disease at a tertiary hospital in South Africa.

Background Predicting severe Crohn's disease (SCD) can assist in planning risk reduction therapy for SCD, thereby improving disease outcomes. Objective To determine the prevalence and predictors of SCD in a sample of South African patients. Methods This was a retrospective chart review of patients with Crohn's disease (CD) attending the Gastroenterology Unit at a tertiary hospital in Durban, South Africa. Demographic and clinical variables at diagnosis of CD were collected and analysed for statistical association with development of SCD (defined as the presence of >/= 1 of the following over the course of CD: complex perianal disease, colonic resection >/= 2 small bowel resections, a single small bowel resection > 50cm, or construction of a definitive stoma). The prognostic utility of statistically significant variables was investigated by establishing their sensitivity, specificity, and predictive values for SCD.  Results The study consisted of 93 patients. The rate of SCD was 64.5%, with 63.3 % of patients developing SCD within 1 year of CD diagnosis. Ileocolonic location (p = 0.046) and penetrating disease at initial diagnosis of CD (p = 0.021) were statistically associated with SCD. The sensitivity, specificity, positive predictive value, and negative predictive value of ileocolonic location for SCD was 72.7%, 47.4%, 66.7% and 54.6%. The sensitivity, specificity, positive predictive value, and negative predictive value of penetrating disease for SCD was 85.7%, 41.7%, 30.0% and 91.0%. Conclusion Most patients with CD developed SCD within 1 year of their CD diagnosis. CD with a penetrating phenotype at diagnosis is a good predictor for the devleopment of SCD and should be further investigated.

Guidance for the gastrointestinal evaluation and management of iron deficiency in Sub-Saharan Africa.

BACKGROUND: Over 30% of the world's population is anaemic, with a significant proportion of these being iron deficient. As iron deficiency (ID) anaemia in men and post-menopausal women is mostly caused by gastrointestinal blood loss or malabsorption, the initial evaluation of a patient with ID anaemia involves referral to a gastroenterologist. The current drive towards patient blood management in sub-Saharan Africa (SSA)prescribes that we regulate not only the use of blood transfusion but also the management of patients in whom the cause of iron loss or inadequate iron absorption is sought. Recommendations have been developed to: (i) aid clinicians in the evaluation of suspected gastrointestinal iron loss and iron malabsorption, and often a combination of these; (ii) improve clinical outcomes for patients with gastrointestinal causes of ID; (iii) provide current, evidence-based, context-specific recommendations for use in the management of ID; and (iv) conserve resources by ensuring rational utilisation of blood and blood products. METHOD: Development of the guidance document was facilitated by the Gastroenterology Foundation of Sub-Saharan Africa and the South African Gastroenterology Society. The consensus recommendations are based on a rigorous process involving 21 experts in gastroenterology and haematology in SSA. Following discussion of the scope and purpose of the guidance document among the experts, an initial review of the literature and existing guidelines was undertaken. Thereafter, draft recommendation statements were produced to fulfil the outlined purpose of the guidance document. These were reviewed in a round-table discussion and were subjected to two rounds of anonymised consensus voting by the full committee in an electronic Delphi exercise during 2022 using the online platform, Research Electronic Data Capture. Recommendations were modified by considering feedback from the previous round, and those reaching a consensus of over 80% were incorporated into the final document. Finally, 44 statements in the document were read and approved by all members of the working group. CONCLUSION: The recommendations incorporate six areas, namely: general recommendations and practice, Helicobacter pylori, coeliac disease, suspected small bowel bleeding, inflammatory bowel disease, and preoperative care. Implementation of the recommendations is aimed at various levels from individual practitioners to healthcare institutions, departments and regional, district, provincial and national platforms. It is intended that the recommendations spur the development of centre-specific guidelines and that they are integrated with the relevant patient blood management protocols. Integration of the recommendations is intended to promote optimal evaluation and management of patients with ID, regardless of the presence of anaemia.

Ontogeny of vocal signals in the little brown bat, Myotis lucifugus

This study reports developmental changes in the vocal signals produced by wild-caught pre-volant and volant Myotis lucifugusAudio recordings were made from young animals (1-33 days old) and adults (over 1 year of age). The animals were removed from an attic maternity roost and studied individually in a room below. To stimulate flight-related behaviours, animals were released from a launching platform via a hinged floor, and their vocalizations were recorded as they approached a soft foam pad below. When the hinged floor opened, the youngest animals (1-4 days old) typically dropped onto the pad, but older animals either flapped their wings to achieve some horizontal displacement (>4 days) or sustained horizontal flight (>17 days). Vocalizations recorded under these conditions showed frequency modulation characteristic of adult echolocation sounds, even in animals as young as 4 days. Ontogenetic trends showed an increase in sound frequency, an increase in sound repetition rate and a decrease in sound duration as the animals matured. These data are discussed in the context of the development of echolocation behaviour in bats.