Antimicrobial bacteria resistance is an important problem in children with recurrent urinary tract infections (rUTI), thus it is crucial to search for alternative therapies. Autologous bacterial lysates (ABL) may be a potential treatment for rUTI. Twenty-seven children with rUTI were evaluated for one year, urine and stool cultures were performed, 10 colonies of each culture were selected and those identified as Escherichia coli were characterized by serology. For patients who presented ≥10⁵ UFC/mL, an ABL was manufactured and administered orally (1 mL/day) for a month. Twelve children were monitored for ≥1-year, 218 urine and 11 stool samples were analyzed. E. coli (80.5%) was the main bacteria isolated from urine and feces (72%). E. coli of classical urinary serotypes (UPEC), O25:H4, O75:HNM, and O9:HNM were identified in patients with persistent urinary infection (pUTI). In 54% of patients treated with ABL, the absence of bacteria was observed in urine samples after 3 months of treatment, 42% of these remained without UTI between 10–12 months. It was observed that the use of ABL controlled the infection for almost 1 year in more than 60% of the children. We consider it necessary to develop a polyvalent immunogen for the treatment and control of rUTI.

Urinary tract infections (UTIs) represent a clinical and epidemiological problem of worldwide impact that affects the economy and the emotional state of the patient. Control of the condition is complicated due to multidrug resistance of pathogens associated with the disease. Considering the difficulty in carrying out effective treatment with antimicrobials, it is necessary to propose alternatives that improve the clinical status of the patients. With this purpose, in a previous study, the safety and immunostimulant capacity of a polyvalent lysate designated UNAM-HIMFG prepared with different bacteria isolated during a prospective study of chronic urinary tract infection (CUTI) was evaluated. In this work, using an animal model, results are presented on the immunostimulant and protective activity of the polyvalent UNAM-HIMFG lysate to define its potential use in the control and treatment of CUTI. Female Balb/c mice were infected through the urethra with Escherichia coli CFT073 (UPEC O6:K2:H1) strain; urine samples were collected before the infection and every week for up to 60 days. Once the animals were colonized, sublingual doses of UNAM-HIMFG lysate were administrated. The colonization of the bladder and kidneys was evaluated by culture, and their alterations were assessed using histopathological analysis. On the other hand, the immunostimulant activity of the compound was analyzed by qPCR of spleen mRNA. Uninfected animals receiving UNAM-HIMFG lysate and infected animals administered with the physiological saline solution were used as controls. During this study, the clinical status and evolution of the animals were evaluated. At ninety-six hours after infection, the presence of CFT073 was identified in the urine of infected animals, and then, sublingual administration of UNAM-HIMFG lysate was started every week for 60 days. The urine culture of mice treated with UNAM-HIMFG lysate showed the presence of bacteria for three weeks post-treatment; in contrast, in the untreated animals, positive cultures were observed until the 60th day of this study. The histological analysis of bladder samples from untreated animals showed the presence of chronic inflammation and bacteria in the submucosa, while tissues from mice treated with UNAM-HIMFG lysate did not show alterations. The same analysis of kidney samples of the two groups (treated and untreated) did not present alterations. Immunostimulant activity assays of UNAM-HIMFG lysate showed overexpression of TNF-α and IL-10. Results suggest that the lysate activates the expression of cytokines that inhibit the growth of inoculated bacteria and control the inflammation responsible for tissue damage. In conclusion, UNAM-HIMFG lysate is effective for the treatment and control of CUTIs without the use of antimicrobials.

Overuse of antimicrobials has greatly contributed to the increase in the emergence of multidrug-resistant bacteria, a situation that hinders the control and treatment of infectious diseases. This is the case with urinary tract infections (UTIs), which represent a substantial percentage of worldwide public health problems, thus the need to look for alternatives for their control and treatment. Previous studies have shown the usefulness of autologous bacterial lysates as an alternative for the treatment and control of UTIs. However, a limitation is the high cost of producing individual immunogens. At the same time, an important aspect of vaccines is their immunogenic amplitude, which is the reason why they must be constituted of diverse antigenic components. In the case of UTIs, the etiology of the disease is associated with different bacteria, and even Escherichia coli, the main causal agent of the disease, is made up of several antigenic variants. In this work, we present results on the study of a bacterial lysate composed of 10 serotypes of Escherichia coli and by Klebsiella pneumoniae, Klebsiella aerogenes, Enterococcus faecalis, Proteus mirabilis, Citrobacter freundii, and Staphylococcus haemolyticus. The safety of the compound was tested on cells in culture and in an animal model, and its immunogenic capacity by analysing in vitro human and murine macrophages (cell line J774 A1). The results show that the polyvalent lysate did not cause damage to the cells in culture or alterations in the animal model used. The immunostimulatory activity assay showed that it activates the secretion of TNF-α and IL-6 in human macrophages and TNF-α in murine cells. The obtained results suggest that the polyvalent lysate evaluated can be an alternative for the treatment and control of chronic urinary tract infections, which will reduce the use of antimicrobials.

The conservation of threatened animal species is essential for maintaining ecosystem stability. The olive ridley sea turtle (Lepidochelys olivacea) is currently classified as Vulnerable by the International Union for Conservation of Nature (IUCN). Embryonic survival is a critical component of L. olivacea conservation programs; therefore, identifying factors that compromise hatching success is a priority. Among these factors, bacterial infections—particularly those caused by Salmonella spp., whose vertical transmission has been reported in reptiles—may adversely affect embryonic development. The objective of this study was to detect Salmonella spp. using conventional bacteriological culture and polymerase chain reaction (PCR) targeting the invA gene, and to evaluate morphological abnormalities in embryos from unhatched eggs. A total of 63 eggs from 24 nests kept in hatchery enclosures on five beaches along the southern Pacific coast of Mexico were analyzed during the 2019 nesting season. Samples of albumen, yolk sac, embryos, and pooled organs were processed. No Salmonella isolates were recovered by bacteriological culture; however, PCR detected Salmonella DNA in 8 of 63 samples (12.7%). Gross and histopathological examination identified nephrocalcinosis (10.9%), coelomitis (5.0%), necrotizing hepatitis (1.6%), dermatitis (1.6%), and developmental malformations in five embryos (10.0%). However, no association was found between the detection of Salmonella DNA and gross or histopathological lesions, suggesting that Salmonella DNA detection was not associated with the embryonic lesions evaluated. These findings highlight the need for further studies to clarify the role of Salmonella during embryonic development in chelonians.

Background: Mastitis is a major disease in dairy production, causing economic losses and increasing concern due to antimicrobial-resistant bacteria. The presence of resistant Staphylococcus spp. in raw milk from clinically healthy animals may represent a potential public health risk and a challenge for control strategies under a One Health framework. Objective: To evaluate antimicrobial resistance patterns and resistance genes in Staphylococcus spp. isolated from raw milk of clinically healthy cows, goats, and ewes from three dairy farms included in this study. Methodology: Seventy-five isolates (25 per species) were analyzed using disk diffusion antibiograms and PCR detection of blaZ, mecA, ermB, and tetK genes. Phenotypic–genotypic agreement and interspecies differences were statistically evaluated. Results: High phenotypic resistance to β-lactams was observed, especially in cows (ampicillin 96%, penicillin 92%) and ewes (penicillin 60%). Oxacillin resistance was higher in goats and ewes (52%) than in cows (8%). Resistance to erythromycin and tetracycline was moderate to low. Gene detection showed high prevalence of mecA (84–100%) and blaZ (80% in cows and goats; 20% in ewes), with significant interspecies differences in blaZ and tetK (p < 0.001). Overall phenotype–genotype agreement was low, although blaZ showed the highest diagnostic value. Frequent codetection of resistance genes was observed among isolates, indicating the coexistence of multiple resistance determinants within the same bacterial populations. Implications: The low phenotype–genotype concordance highlights limitations of relying on a single diagnostic approach and suggests the need for integrated surveillance combining phenotypic and molecular tools. Conclusion: Antimicrobial-resistant Staphylococcus spp. are widely present in raw milk from clinically healthy ruminants, with significant interspecies differences. The present study revealed marked differences in antimicrobial resistance profiles and resistance gene distribution among Staphylococcus spp. isolated from cows, goats, and ewes. The low phenotype–genotype concordance observed for several antibiotic–gene pairs highlights the complexity of antimicrobial resistance and supports the complementary use of phenotypic and molecular approaches for surveillance and characterization of resistant isolates.