Disease Severity, Fever, Age, and Sex Correlate With SARS-CoV-2 Neutralizing Antibody Responses

Clinical trials on the use of COVID-19 convalescent plasma remain inconclusive. While data on safety is increasingly available, evidence for efficacy is still sparse. Subgroup analyses hint to a dose-response relationship between convalescent plasma neutralizing antibody levels and mortality. In particular, patients with primary and secondary antibody deficiency might benefit from this approach. However, testing of neutralizing antibodies is limited to specialized biosafety level 3 laboratories and is a time- and labor-intense procedure. In this single center study of 206 COVID-19 convalescent patients, clinical data, results of commercially available ELISA testing of SARS-CoV-2 spike-IgG and -IgA, and levels of neutralizing antibodies, determined by plaque reduction neutralization testing (PRNT), were analyzed. At a medium time point of 58 days after symptom onset, only 12.6% of potential plasma donors showed high levels of neutralizing antibodies (PRNT50 >= 1:320). Multivariable proportional odds logistic regression analysis revealed need for hospitalization due to COVID-19 (odds ratio 6.87; p-value 0.0004) and fever (odds ratio 3.00; p-value 0.0001) as leading factors affecting levels of SARS-CoV-2 neutralizing antibody titers in convalescent plasma donors. Using penalized estimation, a predictive proportional odds logistic regression model including the most important variables hospitalization, fever, age, sex, and anosmia or dysgeusia was developed. The predictive discrimination for PRNT50 >= 1:320 was reasonably good with AUC: 0.86 (with 95% CI: 0.79-0.92). Combining clinical and ELISA-based pre-screening, assessment of neutralizing antibodies could be spared in 75% of potential donors with a maximal loss of 10% of true positives (PRNT50 >= 1:320)

Relationships between Inflammatory Biomarkers and Fatigue among Patients with Moderate and Severe COVID-19

Background. Patients with moderate or severe COVID-19 infection suffer from varying levels of fatigue; however, there is a lack of understanding regarding the effect of inflammation on fatigue; and whether these relationships differ according to the severity of the infection. Aim. To assess the relationships between selected inflammatory biomarkers and fatigue levels among hospitalized Jordanian patients with moderate or severe COVID-19 infection. Methods. A quantitative cross-sectional design was used. A total of 352 participants were recruited for the study. Data regarding fatigue type and level were collected using the Chalder fatigue scale. Laboratory test results regarding several selected inflammatory biomarkers (e.g., ESR, CRP, IL-6, D-dimer, and others) were collected from patient records. The severity of the COVID-19 infection was determined using the criteria of the Ministry of Health in Jordan based on the results of O2% (oxygen saturation). Results. The mean scores of the total fatigue level significantly differed between the two levels of the severity of COVID-19 infection (moderate and severe levels) (t = −3.0, p<0.05). Similar findings were observed with physiological fatigue (t = −3.50, p<0.05), and no significant difference was observed in psychological fatigue. Out of the selected inflammatory markers, only neutrophil and lymphocyte count had a significant influence on total fatigue level. Conclusion. The level and type of fatigue was affected by the severity of the disease. However, the disease process itself represented by the levels of the inflammatory markers showed little influence on fatigue. The implications such as continuous screening of fatigue, and monitoring of the levels of the inflammatory markers are important to assist in diagnosing and managing COVID-19 patients. Furthermore, the relationship between the inflammatory process and fatigue is complex and requires further exploration

Evaluation of cochleo-vestibular functions in patients with auditory neuropathy

Background: Auditory neuropathy (AN) is a specific hearing disorder with abnormal auditory neural responses in the presence of normal cochlear function. Affection of vestibular portion of cochleo-vestibular (VIII) nerve was only reported in few studies. Objectives: To evaluate the cochleo-vestibular function in these patients and to detect any relationship between both cochlear and vestibular functions. Method: The study was conducted on forty (AN) patients. All subjects were submitted to: full audiological test battery; history taking, clinical otological examination, basic audiological evaluation, Auditory Brainstem Response (ABR), Transient Evoked Otoacoustic Emissions (TEOAEs) and threshold equalizing test (TEN). Vestibular test battery; (vestibular evoked myogenic potential (VEMP) and VNG test battery). Results: Audiological test battery confirmed the audiological criteria for auditory neuropathy reported in the literature. Results of this work showed that, there was preservation of TEOAE in all patients. Also, there was an increase in amplitude of CM in AN. Moreover, all AN patients showed presence of dead regions that started first in low frequencies and with increase number of dead regions the mid and high frequencies also affected. In addition to that the vestibular function tests showed that VEMP was preserved bilaterally in 15 patients, unilateral in 10 patients and absent in 15 patients. On the other side, VNG showed normal central vestibular system with unilateral weakness in 10 ears only. Conclusion: Patients with auditory neuropathy could also have vestibular neuropathy. Vestibular neuropathy could be classified into three groups: superior vestibular neuropathy, inferior vestibular neuropathy and superior/inferior vestibular neuropathy