Patients with Covid-19 exhibit different immunological profiles according to their clinical presentation.

OBJECTIVES: A novel beta coronavirus has been identified as responsible for the 2019 coronavirus infection (Covid-19). Clinical presentations range from asymptomatic cases to acute respiratory distress syndrome with fatal outcome. Such a broad spectrum of disease expression calls for an investigation of immune response characteristics. METHODS: We identified subjects admitted for Covid-19 in whom a large panel of immunological markers were measured, including B- and T- and NK-lymphocyte phenotypes, T-lymphocyte subpopulation cells and plasma cytokines. Patients were divided according to symptom severity during hospitalisation, in those with uncomplicated and complicated infection. Differences between groups were analyzed. RESULTS: Seventeen patients were included (mean age: 83 years; 9 women; mean delay of symptoms onset: 4 days). Six had uncomplicated infection, while 11 developed complicated forms during hospitalization. CD10 + B lymphocyte levels were inversely correlated with clinical severity (5.8% vs 2.0%, p = 0.04) and CD10+ levels above 3% were independently associated with uncomplicated forms [Odds Ratio 0.04 (CI 0.002-0.795, p = 0.034)]. TNF-alpha, IL-1, Il-6 and Il-8 measurements upon admission differed between patients who died and those who survived (p < 0.01 for all comparisons). CONCLUSIONS: In a population of elderly patients recently infected with Covid-19, CD10 + B cell levels were inversely correlated with clinical severity. Cytokine values upon admission were highly predictive of fatal outcome during hospitalisation. These findings could explain differences in the clinical presentation and allow rapid identification of patients at risk for complications.

[Difficulties of interpretation in toxoplasma serology in a pregnant woman in the context of a maternofetal alloimmunization against HPA-1a platelet antigen]. / A propos d'un cas de sérologie toxoplasmique chez une patiente enceinte dans un contexte d'allo-immunisation foetomaternelle anti-HPA-1a.

Serological status in case of Toxoplasma gondii infection needs to be established either before or at the beginning of a pregnancy. However, clinical biologists are often facing conflicting serological results that are difficult to interpret: we report here the case of a woman in her 30th week of pregnancy. Both her IgM and IgG were negative at the 14th week of pregnancy; but suddenly, starting from the 20th week, her IgG became positive while her IgM remained negative. We remind here of the most frequent hypothesis that can explain a sudden and isolated increase of anti-T. gondii IgG: Is it a technical problem (specificity)? Is it a drug interference? Eventually, we found that the patient was receiving, since the 16th week of pregnancy, every week an intravenous perfusion of polyvalent immunoglobulins. Since we didn't know if the IgG present in this perfusion can protect the patient against toxoplasmosis, we decided to consider this women as non immune.