Fernando Sierra

Acute hepatitis due to shen-min: a herbal product derived from Polygonum multiflorum.

Shen-Min is a herbal product sold as a supplement for women to enhance hair growth. It is widely available across Asia, Europe, and the United States and sold without prescription as a hair nutritional supplement. We describe a case of acute liver injury in a 28-year-old white woman who developed symptomatic hepatitis 8 weeks after starting Shen-Min. All other potential causes of acute hepatitis including viral, hypoxic/ischemic, metabolic, and autoimmune etiologies were excluded. The liver injury slowly resolved over 3 weeks after discontinuing the herbal product. Although the mechanism of Shen-Min hepatotoxicity is unknown, we suspect an idiosyncratic reaction because the patient developed a fine maculopapular rash, mild eosinophilia, and did not overdose. Shen-Min is a Chinese herbal product with a mixture of several plants and vitamins including Polygonum multiflorum, a root that has been previously associated with hepatotoxicity. Nonetheless to our knowledge this is the first reported case of herbal-induced hepatotoxicity in a patient taking Shen-Min per se. Clinicians taking care of patients with acute hepatitis of unclear etiology should be aware that the consumption of Shen-Min, a hair supplement widely available in the United States and Western countries might cause acute hepatitis.

Evidence-Based Medicine (EBM) in practice: applying number needed to treat and number needed to harm.

Evidence-Based Medicine (EBM) in Practice: Applying Number Needed to Treat and Number Needed to Harm

Evidence-based medicine (EBM) in practice: agreement between observers rating esophageal varices: how to cope with chance?

In clinical medicine, several tests that are commonly performed (i.e., physical exams, x-rays, or endoscopy) rely on a degree of subjective interpretation by observers. A limitation for clinicians is the concept of agreement between two observers that is present and beyond chance. Clinical decisions based on the presence or absence of a finding in a diagnostic test (i.e., size of esophageal varices on endoscopy) are commonly reached depending on the agreement between observers. Observations that measure the agreement between two or more observers should include a formula that takes into account the fact that observers will sometimes agree or disagree by chance. The kappa statistic corrects for this chance agreement and lets the reader know how much of the agreement beyond chance the reviewers achieve. Kappa is widely used to measure interobserver variability, that is, how often two or more observers agree in their interpretations. A kappa of 1 indicates perfect agreement, whereas a kappa of 0 indicates agreement equivalent to chance. A limitation of kappa is that it is affected by the prevalence of the finding under observation.

The role of likelihood ratio in clinical diagnosis: Applicability in the setting of spontaneous bacterial peritonitis

Despite imperfect clinical information and uncertainty about clinical course and outcome, the clinicians main task is to make reasonable decisions about patient care. The clinical history and physical examination typically provide information that is useful for making a diagnosis; however, we still rely on laboratory and radiologic tests to confirm a diagnosis in most cases. Understanding the operative characteristic of a test is of key importance because it can change the probability that a patient has a disease before the result of a test is known. This operative characteristic, better known as the likelihood ratio (LR), is a global assessment of the information provided by a test. The LR allows calculating the odds that a patient has a disease after a test is performed. In this article, we explain the meaning of the LR, how it works, and the applicability of this tool in the setting of a challenging scenario in clinical practice, spontaneous bacterial peritonitis.

Efficacy and Tolerability of Guanylate Cyclase-C Agonist: Encouraging Results With Insignificant Clinical Importance

To the Editor: The systematic review written by doctor Eric D Shah, Hyungjin Myra Kim, and Phillip Schoenfield on “Efficacy and tolerability of guanylate Cyclase-C agonist for irritable bowel syndrome with constipation and chronic Idiopathic constipation” [1] is an example of an excellent paper with important relative measurement of effect size finding. The authors conclude that, “both linaclotide and plecanatide demonstrate similar efficacy and tolerability in treating IBS-C and CIC. No difference in odds ratio between linaclotide and plecanatide.” The article expresses its findings in terms of odds ratio (OR) and number needed to treat (NNT). Performance for the treatment of CIC with linaclotide at a dose of 72 μg reports an OR = 3.11 with a NNT = 12, Linaclotide at a dose of 145 μg the OR = 3.25 and the NNT = 10, plecanatide at a dose of 3 mg the OR = 1.99 with a NNT = 11 and plecanatide at a dose of 6 mg the OR = 1.90 with a NNT = 12. Moreover, performance of IBS-C treatment with linaclotide at a dose 290 μg reports an OR = 2.43 with a NNT of 6, plecanatide 3 mg with an OR = 1.87 and a NNT = 9. All of these measures show an important OR indicating the positive relative measure that therapy with plecanatide and linaclotide is effective for the treatment for IBS-C and CIC. Being this true, it is extremely important to highlight that all of this results are relative to placebo! As a relative measure OR is impressive but when we look at the number needed to treat an absolute measure of each therapy we can conclude that these medications have a tiny clinical effect. Digging a little bit into data we can see that these information does not express the real practical significance of the therapy studied. When the likelihood ratio to be helped or to be harmed (LHH) [2] by a procedure is calculated, you can find a different perspective. Treatment with Linaclotide at a dose of 72 μg shows a LHH of 0.08 vs 0.11; 1.3:1 against linaclotide is meaning that more people gets harmed by the intervention than the people it helps. A higher dose of Linaclotide 145 μg reduces the amount of people harmed against the amount of people improved by the therapy with a LHH of 0.1 vs 0.11; 1:1, the same to be helped or to be harmed. On the other hand, the treatment of plecanatide with 3 mg and 6 mg shows a LHH of 0.11 vs 0.03; 3:1in favor of plecanatide. For IBS-C treatment linaclotide 290 μg the LHH of 1:1, the same to be helped or to be harmed. Plecanatide at a dose of 3 mg the LHH is 0.11 vs 0.03; 3.5:1, and plecanatide 6 mg the LHH is 0.11 vs 0.02; 5.5:1. In conclusion when we look at the whole picture analyzing OR, NNT, number needed to harm, and likelihood to be helped or to be harmed, we find that the therapy with guanylate cyclase-C agonist is not as effective therapy for IBS-C and CIC as it seems to be.

Architectural Envelope Systems Based on Triply Periodic Minimal Surfaces

This paper presents the results of a research project, which explores Triply Periodic Minimal Surfaces (TPMS) as a source of inspiration for the design of interior architectural envelopes. TPMS are a large family of surfaces that are not yet fully discovered. This work begins by identifying the members of this family which geometrical characteristics and growth patterns show potential for applications in interior architecture; this selection is made by means of a geometric analysis of these surfaces. The central part of the paper proposes three alternative manufacturing techniques for built approximations of TPMS: ruled surfaces, discrete surfaces and warped surfaces. These were then tested in the development of three modular systems of perforated and permeable surfaces, which were designed using simple construction methods intended to be replicable in different contexts. The components of the systems were manufactured with recyclable and recycled materials (i.e. waste products) and employing local tools and technical resources. The results of this research aim to highlight and explore the formal and geometric benefits of TPMS in the design of architectural components. The main advantages identified in the proposed systems relate to acoustic properties, structural performance and constructional process. It is suggested that the contributions of this research can be used both for educational purposes within academia and commercial purposes in future developments of the systems.