Efficacy and Safety of Vitamin D Supplementation to Prevent COVID-19 in Frontline Healthcare Workers. A Randomized Clinical Trial

Background

Associations between vitamin D (VD) deficiency and the risk of SARS-CoV-2 infection have been documented in cross-sectional population studies. Intervention studies in patients with moderate to severe COVID-19 have failed to consistently document a beneficial effect.

Objective

To determine the efficacy and safety of VD-supplementation in the prevention of SARS-CoV-2 infection in highly exposed individuals.

Methods

A double-blind, parallel, randomized trial was conducted. Frontline healthcare workers from four hospitals in Mexico City, who tested negative for SARS-CoV-2 infection, were enrolled between July 15 and December 30, 2020. Participants were randomly assigned to receive 4,000 IU VD (VDG) or placebo (PG) daily for 30 d. RT-PCR tests were taken at baseline and repeated if COVID-19 manifestations appeared during follow-up. Serum 25-hydroxyvitamin D3 and antibody tests were measured at baseline and at day 45. Per-protocol and intention-to-treat analysis were conducted.

Results

Of 321 recruited subjects, 94 VDG and 98 PG completed follow-up. SARS-CoV-2 infection rate was lower in VDG than in PG (6.4 vs. 24.5%, p <0.001). The risk of acquiring SARS-CoV-2 infection was lower in the VDG than in the PG (RR: 0.23; 95% CI: 0.09–0.55) and was associated with an increment in serum levels of 25-hydroxyvitamin D3 (RR: 0.87; 95% CI: 0.82–0.93), independently of VD deficiency. No significant adverse events were identified.

Conclusions

Our results suggest that VD-supplementation in highly exposed individuals prevents SARS-CoV-2 infection without serious AEs and regardless of VD status.

[Utilidad del índice de choque para predecir la mortalidad en pacientes pediátricos con sepsis grave o choque séptico]

Introducción

La sepsis en pediatría es la principal causa de muerte hospitalaria. Se han intentado crear herramientas que faciliten su identificación, como el índice de choque (IC), definido como el cociente entre frecuencia cardíaca y tensión arterial sistólica. El objetivo de este trabajo fue identificar el mejor momento del IC para predecir la mortalidad en pacientes pediátricos con sepsis grave y choque séptico.

Métodos

Cohorte retrospectiva con 165 pacientes pediátricos que desarrollaron sepsis grave y choque séptico en la Unidad de Terapia Intensiva Pediatrica. Se calculó el IC al diagnóstico (IC0), a las dos, cuatro y seis horas posteriores al mismo (IC2, IC4 e IC6). Se crearon dos grupos según el desenlace (sobrevivientes/muertos). La comparación estadística se realizó con prueba U-Mann Whitney y χ². Se compararon los factores de riesgo entre los sobrevivientes y muertos, calculando la razón de momios (RM).

Resultados

Se comparó el valor del IC entre grupos; en el grupo de choque séptico, el IC se encontró más elevado en IC4 e IC6 (p = 0.010 y p = 0.005). Se encontró que, en los pacientes muertos, el IC incrementó progresivamente su valor en IC4 e IC6 (p < 0.05). Los valores de IC4 e IC6 elevados incrementaron el riesgo de muerte en los pacientes (IC4, RM: 442.1; IC 95% [intervalo de confianza al 95%]: 54.2-3,601.7; p < 0.001; e IC6, RM: 81,951.3; IC 95%: 427.1-15,700,000; p < 0.001).

Conclusiones

La elevación del valor del IC se asocia con mayor mortalidad de la sepsis. El valor de IC6 es el más útil para predecir mortalidad.

Background

Pediatric sepsis is considered the main cause of hospital death around the world. Many groups have tried to create tools that facilitate its early identification, as the shock index (SI) defined as the ratio between cardiac frequency and systolic blood pressure. The objective of this study was to determine the utility of SI to predict mortality in pediatric patients with severe sepsis and septic shock.

Methods

Retrospective cohort with 165 pediatric patients with severe sepsis or septic shock in the Pediatric Intensive Care Unit. SI was calculated at diagnosis, 2, 4 and 6 hours after (SI2, SI4 and SI6). We divided the population in two groups depending their outcome: survivors and non-survivors. The statistical analysis was performed with U Mann-Whitney and chi squared tests. The risk factors were compared between the survivors and the dead, and we calculated the odds ratio (OR).

Results

The median value of SI was compared between groups; in the group of septic shock, SI showed a tendency to remain high in SI4 and SI6 (p = 0.010 and p = 0.005, respectively). Among the survivors and the non-survivors, we found that in the latter, SI was progressively increased in SI4 and SI6 (p < 0.05). High values of SI4 and SI6 increased the risk of death in patients (SI4: OR: 442.1; CI 95% [confidence interval 95%]: 54.2-3,601.7; p < 0.001 and SI6: OR: 81,951.3; CI 95%: 427.1-15,700,000]; p < 0.001).

Conclusions

High values of SI are associated with increased mortality. The IS6 value is the most useful to predict mortality.

Direct medical costs of neonatal respiratory distress syndrome in two specialized public hospitals in Mexico

Objective. To estimate direct medical costs (DMC) associated with treatment of Respiratory Distress Syndrome (RDS) in newborns (NB) in two specialized public hospitals in Mexico. Materials and methods. The perspective used was health care payer. We estimated DMC associated with RDS management. The pattern of resource use was established by reviewing clinical records. Microcosting and bootstrap techniques were used to obtain the DMC. Estimated costs were reported in 2011 US dollars. Results. Average DMC per RDS event was 14226 USD. The most significant items that account for this cost were hospitalization (38%), laboratory and diagnostic exams (18%), incubator time (10%), surfactant therapy (7%), and mechanical ventilation (7%). Conclusion. Average DMC in NB with RDS fluctuated in relation to gestational age weight at birth and clinical complications presented by patients during their hospitalization.

Morphometric study of the ventricular segment of the human fetal heart between 13 and 20 weeks' gestation

Our objective was to determine the normal dimensions of the ventricular segment of the human fetal heart between 13 and 20 weeks' gestation.

STUDY DESIGN

103 hearts obtained by necropsy were dissected and measurements of different portions of ventricles were determined under stereoscopic magnification. In each ventricle were measured anteroposterior and lateral diameters, inlet and outlet length, and thickness of walls at different levels. Our results showed the cardiac apex was constituted by the left ventricle in 68.9% of the hearts. Both ventricles showed linear growth during this period of fetal development. Ranges in median values of external and internal ventricular measurements were determined. The left ventricular wall was thicker than the right, and the right ventricular cavity was larger. This study provides morphometric reference information concerning the dimensions and growth of both ventricles of the fetal heart, which may be useful in pediatric cardiac surgery and echocardiography.

Lipopopeptidephosphoglycan from Entamoeba histolytica activates human macrophages and dendritic cells and reaches their late endosomes

Lipopopeptidephosphoglycan (LPPG) is a complex macromolecule from the surface of Entamoeba histolytica trophozoites. We analysed the interaction between LPPG and human macrophages and dendritic cells (DCs) and found that LPPG is internalized by these cells and activates them. The internalization process involves intracellular traffic from the cell membrane to late endosomes, as shown by co-localization of LPPG with late endosomes marked with FITC-dextran and LAMP-1. LPPG-activated DCs have increased expression of co-stimulatory molecules CD80, CD86 and CD40 and produce pro-inflammatory cytokines TNF-alpha, IL-8 and IL-12. Taken together, these results show that LPPG activates antigen-presenting cells and reaches intracellular compartments that are involved in antigen presentation.

Triggering receptor expressed on myeloid cells (TREM-1) is regulated post-transcriptionally and its ligand is present in the sera of some septic patients

Inflammation is necessary for survival, but it is also an important cause of human morbidity and mortality, as exemplified by sepsis. During inflammation, cells of the innate immune system are recruited and activated in response to infection, trauma or injury. These cells are activated through receptors, such as Toll-like receptors (TLRs), which recognize microbial ligands such as lipopolysaccharide (LPS). Triggering receptor expressed on myeloid cells (TREM)-1 amplifies the inflammatory response initiated by TLRs, and its expression on the surface of monocytes increases in the presence of TLR ligands. Here we have shown that in monocytes TREM-1 mRNA levels, measured by reverse transcription-polymerase chain reaction (RT-PCR), remained unchanged and TREM-1 protein levels, measured by flow cytometry, increased, indicating that LPS increases TREM-1 expression by a post-transcriptional mechanism. We also showed that TREM-1/Fc fusion protein decreased the ability of the sera of some patients with sepsis to activate monocytes, indicating that the TREM-1 ligand, whose identity is unknown, may be present in the sera of some of these patients. We describe a mechanism for the regulation of TREM-1 expression on monocytes and the possible presence of its ligand in serum; these findings help to explain the contribution of TREM-1 during systemic inflammation.

Frequency of low carnitine levels in children on dialysis

To determine the frequency of low carnitine levels, we measured serum carnitine in pediatric patients on peritoneal dialysis (PD) and hemodialysis (HD). Our prospective cross-sectional study was conducted from September 2004 to March 2005 in a single pediatric center, and included patients under 17 years of age who had been on HD or PD for more than 3 months. Patients with primary carnitine deficiency were excluded. A 4-day food diary was used for carnitine intake quantification. Serum total and free carnitine and acylcarnitine were measured. We compared patients with low and normal carnitine levels using the chi-square test, Mann-Whitney U-test, and Spearman correlation. Of 100 study patients, 70 were on PD, and 61 were male. The median age was 13 years, and the median time on dialysis, 10.5 months. Median serum free carnitine was 32.75 nmol/mL. Carnitine levels were lower than normal in 75 patients and reached the level of deficiency in 29. No difference was found between the dialysis modality types for any fraction of carnitine. No correlation was found between the level of free carnitine and time on dialysis (r = -0.009, p = 0.9) or carnitine intake (r = -0.84, p = 0.4). In conclusion, the frequency ofl ow serum carnitine among pediatric patient on dialysis is high.

Morphometric study of the human fetal heart I. Arterial segment

This study measured the dimensions of the great arteries of normal human fetal hearts at an early fetal stage (between 13-20 weeks post-fertilization) in 103 fetuses obtained by necropsy. Different segments of the aorta and the pulmonary artery were dissected and their external diameters measured under stereoscopic magnification. All segments showed linear growth during this period of fetal development. Ranges in median values of external diameters associated with the pulmonary artery were: 2.1-4.2 mm for the valve ring; 2.2-4.2 mm for the main pulmonary trunk; 1.2-2.5 mm for the right pulmonary artery; 0.9-2.18 mm for the left pulmonary artery; and 4.0-8.0 mm for the length of the main pulmonary trunk. Similarly, in the aorta, median diameters were: 2.1-4.2 mm for the ascending aorta; 1.92-3.8 mm for the aortic arch; 1.45-3.0 mm for the aortic isthmus; and 1.75 -3.35 mm for the descending aorta. The diameter of the ductus arteriosus ranged between 1.2-2.45 mm. The growth rates of the pulmonary artery and the aorta were similar. The diameter of the ascending aorta was found to be greater than that of the descending aorta and the right pulmonary artery was wider than the left pulmonary artery. In addition, the magnitude of growth in the various aortic segments was different and the ratios obtained between the aortic isthmus and the ascending and descending aortae, ranged between 0.66-0.93. This study provides important morphometric reference information concerning the dimensions and growth of the great arteries of the fetal heart and has clinical application in pediatric cardiac surgery and echocardiography.

Security and maximal tolerated doses of fluvastatin in pediatric cancer patients

BACKGROUND

The role of cholesterol in neoplasic cell growth and its inhibition by drugs has recently been studied. Cholesterol biosynthesis inhibitors have been used as adjuvants in the treatment of cancer and possibly as prophylactic in carcinogenesis.

OBJECTIVE

The objective of the study was to determine the maximal tolerated doses (MTD) and toxic effects of fluvastatin in pediatric cancer patients.

METHODS

This study was carried out in a third level Social Security Hospital in Mexico City. We included pediatric patients from April 1996 to May 1997. All were terminal cancer patients who did not respond to conventional therapies. Fluvastatin was given p.o. at doses of 2 mg/kg/day for 14 days every 4 weeks in three patients. Subsequent cohorts of three patients each had increments of 2 mg/kg/day of the drug until maximal tolerated doses were found. Toxic effects of the drug were evaluated by physical exploration, laboratory assays and a questionnaire given to each patient.

RESULTS

Twelve patients were included. Diagnoses included two osteosarcomas, eight central nervous system tumors, one lung tumor, and one Ewing's sarcoma. Ten patients died within 1 to 18 months. Two are alive 22 months after inclusion into the study, both with anaplasic astrocytoma. A total of 27 courses were administered. The MTD was 8 mg/kg/day. Toxic effects were insomnia, nausea, vomiting, abdominal distention and myalgias. Toxicity was dose-dependent. Laboratory assays demonstrated no significant changes during treatment.

CONCLUSIONS

Fluvastatin can be safely used at doses of 8 mg/kg/day in pediatric patients with cancer. This dose should be used in additional trials.

Empirical antimicrobial therapy in pediatric patients with neutropenia and fever. Risk factors for treatment failure

BACKGROUND

The use of combinations of antibiotics has been the cornerstone of therapy for febrile patients with cancer and severe neutropenia. Each empirical regimen should be selected according to the epidemiology and susceptibility patterns in each center. We describe here the experience with empirical antimicrobial treatments in pediatric patients with cancer, fever and severe neutropenia, and identify the risk factors associated with treatment failure.

METHODS

This is a prospective study including 145 patients with cancer, and 171 episodes of neutropenia and fever. Blood cultures were taken before initiating empirical treatment: a) carbenicillin (400 mg/kg/day) plus amikacin (21 mg/kg/day) (Cb/ak), and b) ceftazidime (100 mg/kg/day), plus amikacin at the same dosage (Cz/ak).

RESULTS

The overall response rate was 54.9% and 56.3% for Cb/ak and Cz/ak, respectively. Fifty-seven episodes (33.3%) were microbiologically documented, gram-positive isolated in 38% and gram-negative in 49%. Risk factors associated significantly with treatment failure were acute myelocytic leukemia (AML) (RR 2.59, CI 95% 1.42-4.7, p = 0.003); bacteriological identification (RR = 4.41, CI 95% 2.21-8.8, p < 0.001), and the presence of two or more sites of infection (RR = 2.89, CI 95% 1.03-8.11, p = 0.03).

CONCLUSIONS

The rates of response are similar to the combinations used in the hospital (Cb/ak, Cz/ak). The risk factors associated with treatment failure were AML diagnosis, bacteriological identification, and the presence of two or more sites of infection.

[Instrument to measure quality of life based on daily performance in pediatric patients with leukemia]

The objective of this study was to determine the validity of a questionnaire to measure daily performance as an evaluation of quality of life in pediatric leukemia patients. A questionnaire of the daily activities of a child according to Lickert's criteria was done. A pilot survey was performed in patients without a chronic or disabling disease in order to assess its validity. The impression of the medical attendance of each pediatric patient with leukemia, of their daily performance, was compared with the results of the instrument. A trained nurse applied the questionnaire to 60 mothers of patients (29 female/31 male) as outpatients during the clinical review. Fifteen questionnaires were applied twice to evaluate its consistency. According to the results, 77% of the patients were in remission. 15% in relapse, and 8% during induction to remission. The mean age of the patients was 9 = 3.6 years, ranging from 2-16 years. One hundred percent of the patients obtained a satisfactory grade greater than 35 points. In conclusion, the questionnaire identified adequately the level of the daily performance in addition to the specific affected areas of the patients with leukemia. Our findings are that their level of performance is satisfactory and is not affected because of the disease or the phase of the treatment.