Low Incidence of Symptomatic Thrombotic Events in Adult Patients Hospitalized with Coronavirus 19: A Retrospective Cohort Study

Background

Since the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) pandemic, there have been many reports of increased incidence of venous thromboembolism and arterial events as a complication.

Objective

To determine the incidence of symptomatic thrombotic events (TEs) in patients hospitalized for SARS-CoV2 disease (coronavirus 19 [Covid-19]).

Methods

A retrospective single-center cohort study with adult patients with a positive reverse transcriptase-polymerase chain reaction (rt-PCR) for SARS-CoV2, included from the date of diagnosis of Covid-19 and followed for 90 days or until death.

Results

A total of 1621 patients were included in this study. The median age was 73 years (interquartile range_25th-75th [IQR] 53-87 years) and 57% (913) were female. Overall mortality was 21.6% (348). The overall incidence of symptomatic TEs within 90 days of diagnosis was 1.8% (30 of 1621) occurring in 28 patients, including an incidence of pulmonary embolism of 0.9% (15, 95% confidence interval [CI] 0.60%-1.6%), deep venous thrombosis of 0.61% (10, 95% CI 0.2%-1%), ischemic stroke of 0.25% (4, 95% CI 0.09%-0.65%), and ischemic arterial events of 0.06% (1, 95% CI 0.008%-0.43%). No acute coronary syndrome events were recorded. The incidence of symptomatic TEs was significantly lower in the general ward than in intensive care units (1.2% vs 5.7%; p < .001). The median time since positive rt-PCR for SARS-CoV2 to symptomatic TE was 22.5 days (IQR 19-43 days). There was no significant difference in the proportion of patients receiving (53.6%) and not receiving thromboprophylaxis (66.5%) and the development of TEs.

Conclusion

The overall incidence of symptomatic TEs among these patients was lower than the incidence previously reported.

A Randomized Trial of Convalescent Plasma in Covid-19 Severe Pneumonia

BACKGROUND

Convalescent plasma is frequently administered to patients with Covid-19 and has been reported, largely on the basis of observational data, to improve clinical outcomes. Minimal data are available from adequately powered randomized, controlled trials.

METHODS

We randomly assigned hospitalized adult patients with severe Covid-19 pneumonia in a 2:1 ratio to receive convalescent plasma or placebo. The primary outcome was the patient's clinical status 30 days after the intervention, as measured on a six-point ordinal scale ranging from total recovery to death.

RESULTS

A total of 228 patients were assigned to receive convalescent plasma and 105 to receive placebo. The median time from the onset of symptoms to enrollment in the trial was 8 days (interquartile range, 5 to 10), and hypoxemia was the most frequent severity criterion for enrollment. The infused convalescent plasma had a median titer of 1:3200 of total SARS-CoV-2 antibodies (interquartile range, 1:800 to 1:3200). No patients were lost to follow-up. At day 30 day, no significant difference was noted between the convalescent plasma group and the placebo group in the distribution of clinical outcomes according to the ordinal scale (odds ratio, 0.83; 95% confidence interval [CI], 0.52 to 1.35; P = 0.46). Overall mortality was 10.96% in the convalescent plasma group and 11.43% in the placebo group, for a risk difference of -0.46 percentage points (95% CI, -7.8 to 6.8). Total SARS-CoV-2 antibody titers tended to be higher in the convalescent plasma group at day 2 after the intervention. Adverse events and serious adverse events were similar in the two groups.

CONCLUSIONS

No significant differences were observed in clinical status or overall mortality between patients treated with convalescent plasma and those who received placebo. (PlasmAr ClinicalTrials.gov number, NCT04383535.).

Machine Learning in Melanoma Diagnosis. Limitations About to be Overcome

BACKGROUND

Automated image classification is a promising branch of machine learning (ML) useful for skin cancer diagnosis, but little has been determined about its limitations for general usability in current clinical practice.

OBJECTIVE

To determine limitations in the selection of skin cancer images for ML analysis, particularly in melanoma.

METHODS

Retrospective cohort study design, including 2,849 consecutive high-quality dermoscopy images of skin tumors from 2010 to 2014, for evaluation by a ML system. Each dermoscopy image was assorted according to its eligibility for ML analysis.

RESULTS

Of the 2,849 images chosen from our database, 968 (34%) met the inclusion criteria for analysis by the ML system. Only 64.7% of nevi and 36.6% of melanoma met the inclusion criteria. Of the 528 melanomas, 335 (63.4%) were excluded. An absence of normal surrounding skin (40.5% of all melanomas from our database) and absence of pigmentation (14.2%) were the most common reasons for exclusion from ML analysis.

DISCUSSION

Only 36.6% of our melanomas were admissible for analysis by state-of-the-art ML systems. We conclude that future ML systems should be trained on larger datasets which include relevant non-ideal images from lesions evaluated in real clinical practice. Fortunately, many of these limitations are being overcome by the scientific community as recent works show.

[Timely diagnosis of disseminated paracoccidioidomycosis in an immunocompetent adult]

Paracoccidioidomycosis is endemic in subtropical rainforests of Latin America. Acute/subacute presentations involve an aggressive dissemination throughout the lymphatic system, while chronic forms (more frequent) arise as differential diagnosis for other conditions involving lung, oropharynx, skin, and eventually the brain. We present the case of a man referred for evaluation and treatment of a possible lung tumor with brain metastasis. The finding of multibudded yeasts and the microbiological isolation of a dimorphic fungus identified as Paracoccidioides sp. from a brain biopsy prompted a cardinal change in prognosis and treatment. This case alerts on the importance of considering systemic fungal diseases as differential diagnosis of compatible clinical presentations in patients who had lived in, or visited, endemic areas.