Which laboratory technique is used for the blood sodium analysis in clinical research? A systematic review

Abstract Background Circulating sodium is analyzed by flame spectrometry and indirect or direct potentiometry. The differences between estimates returned by the three techniques are often relevant. It is unknown whether peer-reviewed international publications focusing on this parameter provide information about the technique. Objectives of the study were to ascertain if information about the employed technique is provided. Content A search in the National Library of Medicine for articles whose title contains "hyponatr[a]emia" was performed. We restricted the search to clinical reports including 10 or more humans published in the 2013–2015 and 2017–2019 periods. Authors of papers not reporting the technique were contacted to obtain this information. The study design and journal quartile ranking of each article were also evaluated. Summary For the final analysis, we included 361 articles (2013–2015, n=169; 2017–2019, n=192). Information about the laboratory technique was given in 61(17%) articles. Thanks to our inquiry, we collected this information for 116(32%) further reports. Indirect potentiometry was the most frequently used technique, followed by direct potentiometry. Spectrometry was used in a small minority of studies. Study design, journal ranking and study period did not modulate the mentioned frequency. Outlook Most articles focusing on hyponatremia do not provide information on the laboratory technique. This parameter is nowadays analyzed by indirect or, less frequently, direct potentiometry. The figures are similar for high and low impact factor journals and for the 2013–2015 and the 2017–2019 periods. Many authors, reviewers and editors likely assume that the results of this parameter are not influenced by the technique

Peripheral Facial Nerve Palsy in Severe Systemic Hypertension: A Systematic Review

BACKGROUND Signs of nervous system dysfunction such as headache or convulsions often occur in severe systemic hypertension. Less recognized is the association between severe hypertension and peripheral facial nerve palsy. The aim of this study was to systematically review the literature on the association of peripheral facial palsy with severe hypertension. METHODS Systematic review of Medline, Embase, Web of Science, and Google Scholar from 1960 through December 2011 and report of two cases. RESULTS The literature review revealed 24 cases to which we add two cases with severe hypertension and peripheral facial palsy. Twenty-three patients were children. Palsy was unilateral in 25 cases, bilateral in one case, and recurred in nine. The time between the first facial symptoms and diagnosis of hypertension was a median of 45 days (range, 0 days-2 years). In five case series addressing the complications of severe hypertension in children, 41 further cases of peripheral facial palsy were listed out of 860 patients (4.8%). CONCLUSIONS The association between severe hypertension and peripheral facial palsy is mainly described in children. Arterial hypertension is diagnosed with a substantial delay. Outcome is favorable with adequate antihypertensive treatment. The pathophysiology is still debate

Renal vein obstruction and orthostatic proteinuria: a review

Objectives. The cause of orthostatic proteinuria is not clear but may often relate to obstruction of the left renal vein in the fork between the aorta and the superior mesenteric artery (= renal nutcracker). However, reports dealing with proteinuria only marginally refer to this possible cause of orthostatic proteinuria. We analysed the corresponding literature. Results. Five reports addressed the frequency of renal nutcracker in 229 subjects with orthostatic proteinuria. Their age ranged between 5.2 and 17years (female-to-male ratio: 0.96:1.00). Imaging studies demonstrated renal nutcracker in 156 (68%) subjects. Renal nutcracker was also demonstrated in 9 anecdotal reports for a total of 53 subjects with postural proteinuria. Very recently, 13 Italian subjects with orthostatic proteinuria associated with renal nutcracker were reassessed 6years after the initial diagnosis: in nine subjects, both orthostatic proteinuria and renal nutcracker had disappeared; in three, both orthostatic proteinuria and renal nutcracker had persisted; and in one, orthostatic proteinuria had persisted unassociated with renal nutcracker. Conclusions. These data provide substantial support for renal nutcracker as a common cause of orthostatic proteinuri

Myositis and acute kidney injury in bacterial atypical pneumonia: Systematic literature review.

Abstract Background Bacterial community-acquired atypical pneumonia is sometimes complicated by a myositis or by a renal parenchymal disease. Available reviews do not mention the concurrent occurrence of both myositis and acute kidney injury. Methods In order to characterize the link between bacterial community-acquired atypical pneumonia and both myositis and a renal parenchymal disease, we reviewed the literature (United States National Library of Medicine and Excerpta Medica databases). Results We identified 42 previously healthy subjects (35 males and 7 females aged from 2 to 76, median 42 years) with a bacterial atypical pneumonia associated both with myositis (muscle pain and creatine kinase ≥5 times the upper limit of normal) and acute kidney injury (increase in creatinine to ≥1.5 times baseline or increase by ≥27 μmol/L above the upper limit of normal). Thirty-six cases were caused by Legionella species (N = 27) and by Mycoplasma pneumoniae (N = 9). Further germs accounted for the remaining 6 cases. The vast majority of cases (N = 36) presented a diffuse myalgia. Only a minority of cases (N = 3) were affected by a calf myositis. The diagnosis of rhabdomyolysis-associated kidney injury was retained in 37 and that of acute interstitial nephritis in the remaining 5 cases. Conclusion Bacterial atypical pneumonia may occasionally induce myositis and secondary kidney damage

Body fluids and salt metabolism - Part II

There is a high frequency of diarrhea and vomiting in childhood. As a consequence the focus of the present review is to recognize the different body fluid compartments, to clinically assess the degree of dehydration, to know how the equilibrium between extracellular fluid and intracellular fluid is maintained, to calculate the effective blood osmolality and discuss both parenteral fluid maintenance and replacement

Kidney tubular injury induced by valproic acid: systematic literature review.

BACKGROUND Valproic acid is prescribed for epilepsy and as prophylaxis for bipolar disorder and migraine headaches. It has also been implicated as a cause of a kidney tubular injury. METHODS We undertook a review of the literature to characterize the biochemical and histopathological features of the overt kidney tubular injury and to evaluate the possible existence of a pauci-symptomatic injury. The pre-registered review (CRD42022360357) was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology. Searches were conducted in Excerpta Medica, the National Library of Medicine, and Web of Science. The gray literature was also considered. RESULTS For the final analysis, we retained 36 articles: 28 case reports documented 48 individuals with epilepsy on valproic acid for 7 months or more and presenting with features consistent with an overt kidney tubular injury. The following disturbances were noted: hypophosphatemia (N = 46), normoglycemic glycosuria (N = 46), total proteinuria (N = 45), metabolic acidosis (N = 36), hypouricemia (N = 27), tubular proteinuria (N = 27), hypokalemia (N = 23), and hypocalcemia (N = 8). A biopsy, obtained in six cases, disclosed altered proximal tubular cells with giant and dysmorphic mitochondria. Eight case series addressed the existence of a pauci- or even asymptomatic kidney injury. In the reported 285 subjects on valproic acid for 7 months or more, an isolated tubular proteinuria, mostly N-acetyl-β-glucosaminidase, was often noted. CONCLUSIONS Valproic acid may induce an overt kidney tubular injury, which is associated with a proximal tubular mitochondrial toxicity. Treatment for 7 months or more is often associated with a pauci- or oligosymptomatic kidney tubular injury. A higher resolution version of the Graphical abstract is available as Supplementary information

Characterization of antibody response in asymptomatic and symptomatic SARS-CoV-2 infection

SARS-CoV-2 pandemic is causing high morbidity and mortality burden worldwide with unprecedented strain on health care systems. To investigate the time course of the antibody response in relation to the outcome we performed a study in hospitalized COVID-19 patients. As comparison we also investigated the time course of the antibody response in SARS-CoV-2 asymptomatic subjects. Study results show that patients produce a strong antibody response to SARS-CoV-2 with high correlation between different viral antigens (spike protein and nucleoprotein) and among antibody classes (IgA, IgG, and IgM and neutralizing antibodies). The antibody peak is reached by 3 weeks from hospital admission followed by a sharp decrease. No difference was observed in any parameter of the antibody classes, including neutralizing antibodies, between subjects who recovered or with fatal outcome. Only few asymptomatic subjects developed antibodies at detectable levels

Acceptance of two liquid vitamin D₃ formulations among mothers with newborn infants: a randomized, single-blind trial

In Switzerland, children are prescribed 7.5-12.5 μg per day of vitamin D(3) dissolved in alcohol, but many families do not adhere to the recommendation. The aim of the trial was to compare the acceptance of vitamin D(3) dissolved in alcohol or in medium-chain triglycerides among mothers of Swiss newborn infants. The acceptance was tested in 42 healthy newborn infants (20 girls and 22 boys) aged between 2 and 7 days. Their neonatal body weight ranged between 2.225 and 4.150 kg, and the gestational age between 36 1/7 and 41 3/7 weeks. The blinded mothers rated the facial reaction of their children by pointing on a facial hedonic scale. Thirty eight of the 41 mothers, who brought the comparison to completion, assigned a better score to the oily preparation with no difference in the remaining three cases (P < 0.0001). The acceptance for the oily preparation was significantly better both among mothers whose babies were initially presented the alcoholic preparation and among mothers whose babies were initially presented the oily preparation. Furthermore, the acceptance for the oily preparation was better irrespective of gender of the infant or parity of the mother. In conclusion, from the perspective of mothers, Swiss newborn infants prefer the taste of the oily vitamin D(3) preparation over the alcoholic preparation