Background/Objectives: Erythrocyte alloimmunization is a critical complication impacting the efficacy of transfusion therapy in patients with thalassemia. This study seeks to evaluate the prevalence, characterization, and determinants of erythrocyte alloimmunization in multi-transfused thalassemia patients in south of Morocco. Methods: A retrospective study was conducted at the Moroccan Blood and Blood Derivatives Agency in Marrakech (Morocco) over 2 years, from June 2022 to June 2024, including 89 patients with beta-thalassemia receiving regular transfusions. The clinical, demographic, and transfusion characteristics of patients who developed alloimmunization were compared with those of non-alloimmunized patients. Results: Analysis of 89 β-thalassemia patients in the Marrakech region, mostly young and suffering from major form (67%), shows a significant male predominance (p = 0.004) and a high frequency of blood group O+ (49.4%). Alloimmunization mainly affects major forms and males and is associated with frequent annual transfusions (over 12 per year), usually resulting in the use of 24 to 60 packed red blood cell units annually. Alloimmunized patients mostly present anti-K and anti-E antibodies, indicating the involvement of the Kell and Rh systems. The direct Coombs test was more often positive in these patients (21.4% vs. 7.9%, p < 0.01). Conclusions: The high prevalence of alloimmunization in thalassemia patients in the Marrakech region highlights the need for a rigorous and personalized transfusion strategy, including molecular genotyping and alternative therapies.

The gut microbiota plays a pivotal role in maintaining human health. Composed of billions of microorganisms interacting with the digestive system, it is increasingly recognized for influencing pathophysiological processes beyond the digestive tract, particularly in neurodegenerative diseases. Secondary metabolites produced by the gut microbiota, such as short-chain fatty acids, polyphenols, and bile acids can modulate epigenetic processes in the brain. These epigenetic changes, including activating or inhibiting genes involved in inflammation, neuroprotection, and neuronal repair, may offer new therapeutic perspectives for neurodegenerative diseases such as Alzheimer's and Parkinson's. Therefore, optimizing the gut microbiota and understanding these interactions provide promising avenues for innovative therapies for neurodegenerative diseases. This chapter provides a comprehensive overview of how microbial metabolites exert epigenetic effects and their potential for treating neurodegenerative diseases. It also includes references for further exploration of this exciting field.

Crohn’s disease (CD) is a chronic inflammatory condition of the gastrointestinal tract. This case–control study included 20 patients with CD and 20 healthy controls at Mohammed VI University Hospital in Marrakech. The study aimed to characterize cultivable gut bacterial populations using culture-based methods and the Shannon index and to evaluate the in vitro antimicrobial activity of two Thymus essential oils. Patients were slightly older than controls and were more frequently sedentary, while dietary patterns were similar between the groups. Patients showed higher counts of Escherichia coli, Citrobacter spp., Klebsiella spp., and Enterococcus spp., together with lower Lactobacillus counts. The Shannon index showed a negative correlation with lifestyle score (Spearman’s ρ = −0.735, p = 0.049), while a positive correlation was observed with C-reactive protein levels (Spearman’s ρ = 0.574, p = 0.008). GC/MS analysis identified 30 compounds in T. leptobotrys essential oil and 33 in T. vulgaris essential oil, with carvacrol (87.48%) and thymol (76.41%) as the predominant constituents, respectively. Both essential oils produced inhibition zones against the bacterial strains tested; however, the selectivity index used in this study should be considered an exploratory metric. These findings provide preliminary in vitro evidence of antimicrobial activity and should be further investigated using standardized antimicrobial susceptibility methods and more comprehensive microbiota profiling. Larger studies combining culture-based and sequencing-based approaches are warranted.