Physiologic Response to Exercise or Rhabdomyolysis? Creatine Phosphokinase Elevation in 16 Asymptomatic Firefighters.

BACKGROUND We present a case series of 16 trainee firefighters who presented to the Emergency Department with elevated creatine phosphokinase levels of greater than 14 000 units per liter 3 days after the initiation of intense aerobic exercise. All 16 patients were diagnosed with exercise-induced rhabdomyolysis and were mostly asymptomatic. While exercise-induced rhabdomyolysis often affects untrained individuals who abruptly initiate strenuous exercises, our patients were all physically well-trained and maintained an active training regimen. In review of this unusual case series, we assess the patients' risk factors for exercise-induced rhabdomyolysis and the complications of their elevated creatine phosphokinase levels despite their asymptomatic presentations. CASE REPORT We focus on the exercise routine, hospital admission, and course of treatment for 4 of the 16 patients who gave written consent to participate in the study. Therapy was targeted towards intravenous fluids and the lowering of creatine phosphokinase levels. Patients 1, 2, 3, and 4 were discharged when creatine phosphokinase levels decreased by 17%, 40%, 39%, and 40%, respectively. CONCLUSIONS Given the differing guidelines for diagnosis, treatment, and discharge for asymptomatic exercise-induced rhabdomyolysis, it was unclear if this was a physiologic or pathologic response to exercise, if hospital admission was indicated, and the extent to which creatine phosphokinase had to decrease for discharge. Our aim is to: 1) determine recommendations to prevent muscle injury following exercise, 2) distinguish between physiologic response to exercise and clinically significant muscle damage, and 3) and recommend a course of treatment given asymptomatic presentation.

COVID-19 Infection May Not Produce Lasting Immunity in Non-vaccinated Young Adults: A Retrospective Review of COVID-19 Antibody Data.

Background Despite progress in achieving herd immunity through recovery from previous infection and vaccination efforts, the COVID-19 pandemic continues to be an imminent health concern. Exposure to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral antigen through infection or vaccination facilitates immune system efficacy against future infection, but it is currently unclear how long this immunity lasts. Therefore, understanding the necessary exposures to produce adequate antibody levels and the duration of this humoral response to prevent infection is imperative in updating guidelines for vaccination and ultimately ending this public health crisis.  Aims This study aimed to compare the presence of serum antibodies in younger and older age groups to determine how vaccination and previous infection compare as indicators of immunity against COVID-19. We also evaluated age to determine its role in antibody presence. We hope that this information will be helpful to the public to develop the best recommendations for vaccination guidelines concerning distinct demographics. â€‹ Materials and methods In this retrospective data analysis, we evaluated saliva SARS-CoV-2 test results taken from 309 subjects (192F/117M; median age=53.4) during a community fair in Crawford County, PA. We sorted the subjects into groups based on age, reported infection with the COVID-19 virus, and vaccination status. We then performed a Chi-square analysis to compare the frequency of positive SARS-CoV-2 antibody tests within these groups. Results The vaccinated but not previously-infected cohort (n=146, 81.5%) was significantly more likely to have antibodies than the unvaccinated infected cohort (n=55, 65.5%; p<0.0001). In the previously-infected, unvaccinated cohort, individuals who were 55 and older were more likely to have antibodies than younger individuals (p<0.0157), but no age-dependent difference was observed among vaccinated individuals. Conclusions The results suggest that vaccination provides a more durable immune response than recovery from infection, and there is an age-dependent humoral response following previous infection but not vaccination. Practically speaking, this information implies that despite popular misconception, individuals under the age of 55 must receive a COVID-19 vaccine despite the previous infection as they are significantly less likely to have antibodies following infection than their counterparts who are over the age of 55.