Vitamin D Deficiency in Patients with Diabetes in French Guiana: Epidemiology and Relation with Microvascular and Macrovascular Complications.

Vitamin D (VD) insufficiency is common among patients with diabetes in French Guiana. The study aimed to evaluate the prevalence of VD deficiency in the different type of diabetes encountered and to analyze the relationship between VD deficiency and diabetes complications. METHODS: An observational study was conducted between May 2019 and May 2020 in French Guiana, based on data from the CODIAM study (Diabetes Cohort in French Amazonia), describing the characteristics of patients with diabetes mellitus. Among 600 patients enrolled with diabetes, 361 had an available VD assay. RESULTS: The mean 25(OH)VD (hydroxycalciferol) level was 27.9 ng/mL. The level of VD was inversely proportional to the HbA1c (glycated hemoglobin) level. Patients with angina pectoris had a greater proportion of deficiencies VD < 20 ng/mL than those without angina. By contrast, patients with retinopathy had higher vitamin D concentrations than those without retinopathy. There was no association between vitamin D and arteriopathy, stroke, nephropathy and polyneuropathy. VD deficiency was more frequent in women, and in patients with a high school education. CONCLUSION: The prevalence of VD deficiency was high in patients with diabetes in French Guiana, emphasizing the importance of VD supplementation.

Diagnostic accuracy and acceptability of molecular diagnosis of COVID-19 on saliva samples relative to nasopharyngeal swabs in tropical hospital and extra-hospital contexts: The COVISAL study.

A prospective study was conducted among different intra and extra-hospital populations of French Guiana to evaluate the performance of saliva testing compared to nasopharyngeal swabs. Persons aged 3 years and older with mild symptoms suggestive of COVID-19 and asymptomatic persons with a testing indication were prospectively enrolled. Nasopharyngeal and salivary samples were stored at 4°C before analysis. Both samples were analyzed with the same Real-time PCR amplification of E gene, N gene, and RdRp gene. Between July 22th and October 28th, 1159 persons were included, of which 1028 were analyzed. When only considering as positives those with 2 target genes with Ct values <35, the sensitivity of RT-PCR on saliva samples was 100% relative to nasopharyngeal samples. Specificity positive and negative predictive values were above 90%. Across a variety of cultures and socioeconomic conditions, saliva tests were generally much preferred to nasopharyngeal tests and persons seemed largely confident that they could self-sample. For positive patients defined as those with the amplification of 2 specific target genes with Ct values below 35, the sensitivity and specificity of RT-PCR on saliva samples was similar to nasopharyngeal samples despite the broad range of challenging circumstances in a tropical environment.

Prospective Comparison of Saliva and Nasopharyngeal Swab Sampling for Mass Screening for COVID-19.

Current testing for COVID-19 relies on reverse-transcriptase polymerase chain reaction from a nasopharyngeal swab specimen. Saliva samples have advantages regarding ease and painlessness of collection, which does not require trained staff and may allow self-sampling. We enrolled 776 persons at various field-testing sites and collected nasopharyngeal and pooled saliva samples. One hundred sixty two had a positive COVID-19 RT-PCR, 61% were mildly symptomatic and 39% asymptomatic. The sensitivity of RT-PCR on saliva samples vs. nasopharygeal swabs varied depending on the patient groups considered or on Ct thresholds. There were 10 (6.2%) patients with a positive saliva sample and a negative nasopharyngeal swab, all of whom had Ct values <25 for three genes. For symptomatic patients for whom the interval between symptoms onset and sampling was <10 days sensitivity was 77% but when excluding persons with isolated N gene positivity (54/162), sensitivity was 90%. In asymptomatic patients, the sensitivity was only 24%. When we looked at patients with Cts <30, sensitivity was 83 or 88.9% when considering two genes. The relatively good performance for patients with low Cts suggests that Saliva testing could be a useful and acceptable tool to identify infectious persons in mass screening contexts, a strategically important task for contact tracing and isolation in the community.

Air Drep-A Retrospective Study Evaluating the Influence of Weather Conditions and Viral Epidemics on Vaso-Occlusive Crises in Patients with Sickle Cell Disease Living in French Guiana.

(1) Objectives: French Guiana is the French territory most affected by sickle cell disease (SCD). This study investigates the associations between different environmental factors relative to climate, infectious outbreaks, and emergency visits or weekly hospital admissions for vaso-occlusive crisis (VOC). The identification of risk factors would lead to better patient care and patient management, and more targeted prevention and therapeutic education for patients with SCD in French Guiana. (2) Methods: This study was performed using data collected from the medicalized information system and emergency medical records of Cayenne General Hospital, between 1 January 2010 and 31 December 2016. ARIMA models were used to investigate the potential impact of weather conditions and flu epidemics on VOC occurrence. (3) Results: During the study period, 1739 emergency visits were recorded among 384 patients, of which 856 (49.2%) resulted in hospitalization, 811 (46.6%) resulted in hospital discharge, and 72 (4.2%) in another orientation. Decreased temperature and decreased humidity were both independent factors associated with an increase of VOC cases (p = 0.0128 and p = 0.0004, respectively). When studying severe VOC (leading to hospitalization, with or without prior emergency visit), 2104 hospital admissions were recorded for 326 patients. The only factor associated with severe VOC, in the multivariate analysis, was flu epidemics (p = 0.0148). (4) Conclusions: This study shows a link between climate, flu epidemics, and VOC in French Guiana. Patient's awareness of risks related to climate and flu epidemics should be encouraged, as home prevention measures can help avoid painful crises. Moreover, physicians should encourage patients to get immunized for influenza every year.

Incidence of infantile Pompe disease in the Maroon population of French Guiana.

OBJECTIVES: The aim of this study was to describe the epidemiology of infantile Pompe disease (IPD) in French Guiana, a French overseas territory, by combining a retrospective case records study and a prospective anonymous genotyping in a sample of mothers followed in the two major maternity units of French Guiana. METHODS: We identified 19 newborns with IPD born within a 13-year-period in French Guiana, corresponding to 1/4528 births. All children were born within the African-American Maroon (Bushinengue) community originating from slaves who settled along the Maroni river in the 19th century. We also performed an anonymised screening for all women in postpartum, in the two main maternity units of French Guiana. RESULTS: Genetic investigations revealed that all patients with IPD were homozygotes or compound heterozygotes for two known pathogenic variations: c.2560C>T p.(Arg854*) that has already been reported in African-Americans and c.1942G>A p.(Gly648Ser), a rare previously considered to be variant. We identified no heterozygotes among 453 mothers of various ethnicities in Cayenne, but 15 heterozygotes among 425 mothers (1/27) in Saint-Laurent-du-Maroni (95% CI 1/45 to 1/17), all from the Maroon community, which corresponds to an expected IPD incidence in Maroons of 1/1727 (95% CI 1/1156 to 1/8100). CONCLUSION: The incidence of IPD in the Maroon community is roughly 50 times higher than elsewhere in the world. The presence of only two different variants in all affected patients is compatible with a double founder effect in a relatively small population that has seldom mixed with other regional populations in the past and therefore has a reduced pool of genotypes.