Dujardin A, Lorent M, Foucher Y, et al. - Researchers here examined the correlation between the number of circulating lymphocytes, monitored routinely by complete blood cell counts during outpatient visits, and patient and graft survival following transplantation. Among 2,999 enrolled kidney or combined kidney-pancreas recipients transplanted between 2000 and 2016, 584 patients (19.4%) had deep lymphopenia (under 750 /mm³) and 1,072 (35.7%) had a normal count (over 1,500 /mm³) at the time of inclusion (one year after transplantation). They observed that risks of graft failure, death and viral infection were significantly higher among patient with deep lymphopenia at a given follow-up time vs comparable patients with a normal lymphocyte count at the same time point. Hence, following the first year of transplantation, experiencing deep lymphopenia during follow-up is a risk factor for long-term graft failure, death and viral infection.