Associations of hyponatremia and SIADH with increased mortality, young age and infection parameters in patients with tuberculosis.

BACKGROUND AND OBJECTIVE: Hyponatremia and the syndrome of inappropriate antidiuretic hormone secretion (SIADH) are associated with and can be caused by tuberculosis (TB) through meningitis by locally invading the hypothalamus, adrenal, or pituitary glands or possibly through ectopic ADH production. This study assessed the association of TB mortality with hyponatremia and SIADH in a large cohort of a university hospital in Austria. METHODS: This retrospective study enrolled patients with hyponatremia and patients diagnosed with TB from 01/2001-11/2019 to assess the prevalence of TB in hyponatremia and TB morbidity and mortality in patients with and without hyponatremia. Sex, age, microbiological results, laboratory tests and comorbidities were analysed and used to calculate survival rates. RESULTS: Of 107.532 patients with hyponatremia (0.07%) and 186 patients with TB (43%), 80 patients were diagnosed with both-hyponatremia and TB. Only three TB patients had SIADH, precluding further SIADH analysis. In hyponatremia, young age and high CRP levels showed significant associations with TB diagnosis (p<0.0001). Survival rates of patients diagnosed with TB with moderate to profound hyponatremia were significantly lower than those without hyponatremia (p = 0.002). CONCLUSION: In this study of a large cohort from a tertiary care hospital in a non-endemic area of TB, 0.07% of patients presenting with hyponatremia, but especially younger patients and patients with high CRP values, were diagnosed with TB. Crucially, patients with moderate to profound hyponatremia had a significantly higher mortality rate and thus required increased medical care.

Long-term skin-resident memory T cells proliferate in situ and are involved in human graft-versus-host disease.

The skin contains a population of tissue-resident memory T cells (Trm) that is thought to contribute to local tissue homeostasis and protection against environmental injuries. Although information about the regulation, survival program, and pathophysiological roles of Trm has been obtained from murine studies, little is known about the biology of human cutaneous Trm Here, we showed that host-derived CD69+ αß memory T cell clones in the epidermis and dermis remain stable and functionally competent for at least 10 years in patients with allogeneic hematopoietic stem cell transplantation. Single-cell RNA sequencing revealed low expression of genes encoding tissue egress molecules by long-term persisting Trm in the skin, whereas tissue retention molecules and stem cell markers were displayed by Trm The transcription factor RUNX3 and the surface molecule galectin-3 were preferentially expressed by host T cells at the RNA and protein levels, suggesting two new markers for human skin Trm Furthermore, skin lesions from patients developing graft-versus-host disease (GVHD) showed a large number of cytokine-producing host-derived Trm, suggesting a contribution of these cells to the pathogenesis of GVHD. Together, our studies highlighted the relationship between the local human skin environment and long-term persisting Trm, which differs from murine skin. Our results also indicated that local tissue inflammation occurs through host-derived Trm after allogeneic hematopoietic stem cell transplantation.