Quantitative Ultrasound of Phalanx in Primary and Secondary Osteoporosis: Mini-review and Practical Experience

Objective: Dual x-ray absorptiometry (DXA) is gold standard of bone densitometry, but quantitative ultrasound (QUS) of bone is less expensive and portable. This study was designed to assess its usefulness in secondary osteoporosis diagnosis. Materials and Methods: There were 200 secondary osteoporosis cases (rheumatoid arthritis, hemodialysis, kidney transplant patients, and levothyroxine users) and of those, their phalanx QUS results were compared with normal controls. Also, the QUS and DXA results were compared to find any correlation of these methods for diagnosing osteoporosis. Results: There was not significantly different results compared with normal controls, except for those of hemodialysis patients ( P = .00). Also, the comparison of QUS with DXA results showed no significant correlation except in hemodialysis patients, in both spinal and femoral regions ( P = .023 and .21, respectively), as well as the levothyroxine group’s spinal region ( P = .005). Conclusion: These results suggest that QUS of phalanx may be useful in screening secondary osteoporosis but for establishment of diagnosis, DXA measurements are still needed.

Risk factors associated with hospitalization and evolution in kidney transplant patients with COVID-19: A single-center retrospective cohort study

Background: The SARS -CoV -2 infection has had a major impact on kidney transplant patients. Our single -center experience aims to analyze the risk factors for affected patient hospitalization and predictors of worse clinical outcome on admission. Material and methods: A retrospective cohort study with kidney transplant patients with positive PCR for SARS -CoV -19 between March 16th 2020 and February 11th 2021 was conducted. Demographic characteristics and clinical and laboratory information on admission was collected and analyzed to assess risk factors related to patient hospitalization and disease evolution. Results: Seventy -six kidney transplant recipients diagnosed with COVID -19 were included and divided into hospitalized (n=48) and non- -hospitalized (n=28) patients. Two hospitalized patients were not taken into account for the analysis due to a lack of data, and the remaining patients were divided into mild -moderate (n=25) and severe pneumonia (n=21). Lasso and multivariate logistic regression demonstrated that age (OR 1.041, p=0.039) and hypertension (OR 4.177, p=0.040) were risk factors for hospitalization, while time after transplant (OR 0.993, p=0.029) decreases the probability of being hospitalized. Analyses also revealed that SpO2 ≤92% on admission (OR 8.954, p= 0.026) and overweight/obesity (OR 13.453, p= 0.001) were related to a worse evolution and severe pneumonia among hospitalized recipients. Seven patients died due to COVID -19 complications. Conclusion: Age and hypertension are risk factors for hospitalization among positive COVID -19 patients, while time after transplant decreases the probability of being hospitalized. Overweight/obesity and levels of SpO2 ≤92% on admission were the main risk factors that could help to predict the severity of COVID -19 disease in our series.

Immune Response after SARS-CoV-2 Vaccination in Kidney Transplant Patients

Background and Objectives: The prospective study was conducted to evaluate humoral and cellular immune responses after two doses of BNT162b2 (Pfizer-BioNTech) vaccine and possible relation with other factors (medication, etc.) in kidney transplant patients. Materials and Methods: Out of 167 vaccinated patients, 136 agreed to a follow-up visit three to six weeks after vaccination. Results: Only 39 patients (29%) developed antibody response against SARS-CoV-2 (≥35.2 binding antibody units (BAU)/mL) after full vaccination. Multivariate binary logistic regression analysis showed that predictive factors for good antibody response to the COVID-19 vaccine were better kidney function, higher hemoglobin level, and no use of mycophenolate mofetil for immunosuppression. For seropositive kidney transplant patients there was a significant negative correlation between anti-SARS-CoV-2 antibody titer and CD4/CD8 ratio (Spearman’s correlation coefficient −0.4, p = 0.02), percentage of CD19+ cells (r = −0.37, p = 0.02), and a positive correlation with percentage of CD8+ cells (r = 0.4, p = 0.01). There was an increase of total leucocyte count after vaccination in the total studied population, and in the group of responders. Conclusions: Only one third of kidney transplant patients develop sufficient antibody responses after full COVID-19 vaccination with Pfizer-BioNTech. Better kidney function, higher hemoglobin level, and no use of mycophenolate mofetil for immunosuppression increases the adequacy of response. The antibody titers correlated positively with relative number of CD8+ cells and negatively with CD4/CD8 ratio in responders.

Successful treatment of a kidney transplant patient with COVID-19 and late-onset Pneumocystis jirovecii pneumonia

Background Solid transplant patients are susceptible to Pneumocystis jirovecii pneumonia (PJP). While the vast majority of PJP cases occur within the first 6 months after transplantation, very few PJP cases are seen beyond 1 year post-transplantation (late-onset PJP). PJP and coronavirus disease 2019 (COVID-19, caused by infection with SARS-CoV-2) share quite a few common clinical manifestations and imaging findings, making the diagnosis of PJP often underappreciated during the current COVID-19 pandemic. To date, only 1 case of kidney transplantation who developed COVID-19 and late-onset PJP has been reported, but this patient also suffered from many other infections and died from respiratory failure and multiple organ dysfunction syndrome. A successful treatment of kidney patients with COVID-19 and late-onset PJP has not been reported. Case presentation We present a case of a 55-year-old male kidney transplant patient with COVID-19 who also developed late-onset PJP. He received a combined treatment strategy, including specific anti-pneumocystis therapy, symptomatic supportive therapy, adjusted immunosuppressive therapy, and use of antiviral drugs/antibiotics, ending with a favorable outcome. Conclusions This case highlights the importance of prompt and differential diagnosis of PJP in kidney transplant patients with SARS-CoV-2 infection. Further studies are required to clarify if kidney transplant patients with COVID-19 could be prone to develop late-onset PJP and how these patients should be treated.