Sample Treatment with Trypsin for RT-LAMP COVID-19 Diagnosis

The SARS-CoV-2 coronavirus is responsible for the COVID-19 pandemic resulting in a global health emergency. Given its rapid spread and high number of infected individuals, a diagnostic tool for a rapid, simple, and cost-effective detection was essential. In this work, we developed a COVID-19 diagnostic test, that incorporates a human internal control, based on the Reverse Transcription Loop-Mediated Isothermal Amplification (RT-LAMP). When working with synthetic SARS-CoV-2 RNA, the optimized RT-LAMP assay has a sensitivity of 10 viral copies and can be detected by fluorescence in less than 15 min or by the naked eye in 25 min using colorimetric RT-LAMP. To avoid the RNA extraction step, a pre-treatment of the sample was optimized. Subsequently, a validation was performed on 268 trypsin treated samples (including nasopharyngeal, buccal, and nasal exudates) and amplified with colorimetric RT-LAMP to evaluate its sensitivity and specificity in comparison with RT-qPCR of extracted samples. The validation results showed a sensitivity and specificity of 100% for samples with Ct ≤ 30. The rapid, simple, and inexpensive RT-LAMP SARS-CoV-2 extraction-free procedure developed may be an alternative test that could be applied for the detection of SARS-CoV-2 or adapted to detect other viruses present in saliva or nasopharyngeal samples with higher sensitivity and specificity of the antibody test.

A Very Rare Variant in SREBF2, a Possible Cause of Hypercholesterolemia and Increased Glycemic Levels

Patients with high cholesterol and glucose levels are at high risk for cardiovascular disease. The Sterol Regulatory Element Binding Protein (SREBP) system regulates genes involved in lipid, cholesterol and glucose pathways. Autosomal Dominant Hypercholesterolemias (ADHs) are a group of diseases with increased cholesterol levels. They affect 1 out of every 500 individuals. About 20–30% of patients do not present any mutation in the known genes (LDLR, APOB and PCSK9). ADHs constitute a good model to identify the genes involved in the alteration of lipid levels or possible therapeutic targets. In this paper, we studied whether a mutation in the SREBP system could be responsible for ADH and other metabolic alterations present in these patients. Forty-one ADH patients without mutations in the main responsible genes were screened by direct sequencing of SREBP system genes. A luciferase reporter assay of the found mutation and an oral glucose tolerance test in carriers and non-carriers were performed. We found a novel mutation in the SREBF2 gene that increases transcription levels and cosegregates with hypercholesterolemia, and we found increased glucose levels in one family. SREBP2 is known to be involved in cholesterol synthesis, plasma levels and glucose metabolism in humans. The found mutation may involve the SREBF2 gene in hypercholesterolemia combined with hyperglycemia.

Risk factors associated with retinal vein occlusion

AIMS

Retinal vein occlusion (RVO) is the most frequent retinal vascular disease after diabetic retinopathy in which arterial risk factors are much more relevant than venous factors. The objective was to evaluate the role of risk factors in the development of the first episode of RVO.

SUBJECTS AND METHODS

One hundred patients with RVO [mean age 56 years, 42% females and mean body mass index (BMI) 27.5 kg/m(2)] were recruited consecutively from the outpatient clinic of a tertiary hospital in Valencia (Spain). All subjects underwent clinical assessment including anthropometric and blood pressure measurements and laboratory test including homocysteine, antiphospholipid antibodies (aPLAs) and thrombophilia studies. In half of the subjects, a carotid ultrasonography was performed. Three control populations matched by age, sex and BMI from different population-based studies were used to compare the levels and prevalence of arterial risk factors. One cohort of young patients with venous thromboembolic disease was used to compare the venous risk factors.

RESULTS

Blood pressure levels and the prevalence of hypertension were significantly higher in the RVO population when compared with those for the general populations. There was also a large proportion of undiagnosed hypertension within the RVO group. Moreover, carotid evaluation revealed that a large proportion of patients with RVO had evidence of subclinical organ damage. In addition, homocysteine levels and prevalence of aPLAs were similar to the results obtained in our cohort of venous thromboembolic disease.

CONCLUSIONS

The results indicate that hypertension is the key factor in the development of RVO, and that RVO can be the first manifestation of an undiagnosed hypertension. Furthermore, the majority of these patients had evidence of atherosclerotic disease. Among the venous factors, a thrombophilia study does not seem to be useful and only the prevalence of hyperhomocysteinaemia and aPLAs is higher than in the general population.

Epidemiology of acute carbon monoxide poisoning in a Spanish region

BACKGROUND

In Spain, as in most of the world, the incidence of acute carbon monoxide poisoning is probably underestimated.

METHODS

During an eighteen-month period we studied, by means of a standardized data collection form, all the cases of acute carbon monoxide poisoning that were diagnosed in 2 university hospitals.

RESULTS

During the study, 154 patients were diagnosed with carbon monoxide poisoning. The mean age was 32.2+/-15.5 years. The two principal exposure sites were the kitchen (43%) and bathroom (23%). The majority of the cases related to malfunction of the water heater (30%) and of the central heating (23%) and 68% occurred in the home. Improper combustion of butane (31%), propane (13%), and natural gas (12%) were most frequent. The most prevalent clinical manifestations were headache (94%), dizziness (56%), nausea (45%), loss of consciousness (38%), and weakness (34%). Five patients died. In 14.4%, symptoms suggested delayed neurological syndrome. The largest number of cases of poisoning occurred during the months of December and January.

CONCLUSIONS

Compared with previous Spanish series or with the antecedent year, acute carbon monoxide poisoning has a high prevalence in our region. Two factors appear to be essential to the accurate diagnosis of acute carbon monoxide poisoning: 1) the ability of emergency room physicians to recognize the clinical symptoms of carbon monoxide poisoning and 2) access to a carbon monoxide-oximeter.

Endocarditis caused by Enterococcus avium

Enterococcus avium has rarely been reported as a pathogen in humans. We describe a case of endocarditis caused by E. avium. It responded to ampicillin and gentamicin, although a valve replacement was necessary for severe aortic insufficiency. This microorganism should be regarded as significant in endocarditis.