Many recovered COVID-19 patients show persistent lymphopoenia

Persistent lymphopoenia is common patients who had recovered from the novel coronavirus disease (COVID-19), a recent study has found. Such persistent symptoms seem to be more common among patients with lower serum levels of immunoglobulin (Ig) A.

Researchers retrospectively assessed 116 patients (median age 41 years, 15 percent women) who had recovered from COVID-19. Participants were followed up at an outpatient clinic, during which comprehensive lab testing had been performed. The present study made use of data collected at these sessions, as well as from structured clinical forms and discharge letters.

Thirteen patients (12 percent) were found to have lymphopoenia, in whom lymphocyte counts were below the lab-specific reference range of 1.26–3.35×10⁹/L. Four participants in this subgroup had persistent COVID-19 symptoms, corresponding to a prevalence rate of 31 percent.

Nineteen of the remaining 99 patients with normal lymphocyte counts also had persistent symptoms, corresponding to a prevalence of 19 percent.

Late follow-up was performed 80–102 days after discharge, during which 35 patients remained on the study, of whom five had lymphopoenia. Persistent COVID-19 symptoms were detected in two of the five lymphopoenic patients, as well as in eight of the remaining 22 patients without lymphopoenia.

IgA emerged as the only significant and independent correlate of persistent symptoms, in whom the biomarker was significantly lowered (mean, 172.17±57.95 vs 231.29±97.25 mg/dL; p=0.0219).

Among those who had persistent symptoms, the most common were fatigue (54 percent), dyspnoea (29 percent), and anosmia (25 percent). Common onset symptoms were cough, anosmia, fatigue, fever, myalgia, and headache.