The kappa free light chain index and oligoclonal bands have a similar role in the McDonald criteria.

Intrathecal production of kappa free light chains occurs in multiple sclerosis and can be measured using the kappa free light chain index. Kappa free light chain index values can be determined more easily than oligoclonal bands detection and seem more sensitive than the immunoglobulin (Ig)G index to diagnose multiple sclerosis. We assessed the value of oligoclonal bands, kappa free light chain index cut-offs 5.9, 6.6 and 10.61, and IgG index to diagnose multiple sclerosis with prospectively acquired data from a clinically isolated syndrome inception cohort. We selected patients with sufficient data to determine oligoclonal bands positivity, MRI dissemination in space and time, IgG index and sufficient quantities of paired CSF and blood samples to determine kappa free light chain indexes (n = 214). We used Kendall's Tau coefficient to estimate concordance, calculated the number of additional diagnoses when adding each positive index to dissemination in space and positive oligoclonal bands, performed survival analyses for oligoclonal bands and each index with the outcomes second attack and 2017 MRI dissemination in space and time and estimated the diagnostic properties of oligoclonal bands and the different indexes for the previously mentioned outcomes at 5 years. Oligoclonal bands were positive in 138 patients (64.5%), kappa free light chain-5.9 in 136 (63.6%), kappa free light chain-6.6 in 135 (63.1%), kappa free light chain-10.61 in 126 (58.9%) and IgG index in 101 (47.2%). The highest concordance was between oligoclonal bands and kappa free light chain-6.6 (τ = 0.727) followed by oligoclonal bands and kappa free light chain-5.9 (τ = 0.716). Combining dissemination in space plus oligoclonal bands or kappa free light chain-5.9 increased the number of diagnosed patients by 11 (5.1%), with kappa free light chain-6.6 by 10 (4.7%), with kappa free light chain-10.61 by 9 (4.2%) and with IgG index by 3 (1.4%). Patients with positive oligoclonal bands or indexes reached second attack and MRI dissemination in space and time faster than patients with negative results (P < 0.0001 except IgG index in second attack: P = 0.016). In multivariable Cox models [adjusted hazard ratio (95% confidence interval)], the risk for second attack was very similar between kappa free light chain-5.9 [2.0 (0.9-4.3), P = 0.068] and kappa free light chain-6.6 [2.1 (1.1-4.2), P = 0.035]. The highest risk for MRI dissemination in space and time was demonstrated with kappa free light chain-5.9 [4.9 (2.5-9.6), P < 0.0001], followed by kappa free light chain-6.6 [3.4 (1.9-6.3), P < 0.0001]. Kappa free light chains-5.9 and -6.6 had a slightly higher diagnostic accuracy than oligoclonal bands for second attack (70.5, 71.1 and 67.8) and MRI dissemination in space and time (85.7, 85.1 and 81.0). Kappa free light chain indexes 5.9 and 6.6 performed slightly better than oligoclonal bands to assess multiple sclerosis risk and in terms of diagnostic accuracy. Given the concordance between oligoclonal bands and these indexes, we suggest using dissemination in space plus positive oligoclonal bands or positive kappa free light chain index as a modified criterion to diagnose multiple sclerosis.

Reference values for interleukin-6 in the amniotic fluid of asymptomatic pregnant women.

INTRODUCTION: Nowadays, proinflammatory factors are considered to play an important role in the pathophysiology of threatened preterm labor or chorioamnionitis. The aim of this study was to establish the normal reference range for interleukin-6 (IL-6) levels in the amniotic fluid and to identify factors which may alter this value. MATERIAL AND METHODS: Prospective study in a tertiary-level center including asymptomatic pregnant women undergoing amniocentesis for genetic studies from October 2016 to September 2019. IL-6 measurements in amniotic fluid were performed using a fluorescence immunoassay with microfluidic technology (ELLA Proteinsimple, Bio Techne). Maternal history and pregnancy data were also recorded. RESULTS: This study included 140 pregnant women. Of those, women who underwent termination of pregnancy were excluded. Therefore, a total of 98 pregnancies were included in the final statistical analysis. The mean gestational age was 21.86 weeks (range: 15-38.7) at the time of amniocentesis, and 38.6 weeks (range: 30.9-41.4) at delivery. No cases of chorioamnionitis were reported. The log10 IL-6 values follow a normal distribution (W = 0.990, p = 0.692). The median, and the 5th, 10th, 90th, and 95th percentiles for IL-6 levels were 573, 105, 130, 1645, and 2260 pg/mL, respectively. The log10 IL-6 values were not affected by gestational age (p = 0.395), maternal age (p = 0.376), body mass index (p = 0.551), ethnicity (p = 0.467), smoking status (p = 0.933), parity (p = 0.557), method of conception (p = 0.322), or diabetes mellitus (p = 0.381). CONCLUSIONS: The log10 IL-6 values follow a normal distribution. IL-6 values are independent of gestational age, maternal age, body mass index, ethnicity, smoking status, parity and method of conception. Our study provides a normal reference range for IL-6 levels in the amniotic fluid that can be used in future studies. We also observed that normal IL-6 values were higher in the amniotic fluid than in serum.

Recovery of serum testosterone levels is an accurate predictor of survival from COVID-19 in male patients.

BACKGROUND: SARS-CoV-2 infection portends a broad range of outcomes, from a majority of asymptomatic cases to a lethal disease. Robust correlates of severe COVID-19 include old age, male sex, poverty, and co-morbidities such as obesity, diabetes, and cardiovascular disease. A precise knowledge of the molecular and biological mechanisms that may explain the association of severe disease with male sex is still lacking. Here, we analyzed the relationship of serum testosterone levels and the immune cell skewing with disease severity in male COVID-19 patients. METHODS: Biochemical and hematological parameters of admission samples in 497 hospitalized male and female COVID-19 patients, analyzed for associations with outcome and sex. Longitudinal (in-hospital course) analyses of a subcohort of 114 male patients were analyzed for associations with outcome. Longitudinal analyses of immune populations by flow cytometry in 24 male patients were studied for associations with outcome. RESULTS: We have found quantitative differences in biochemical predictors of disease outcome in male vs. female patients. Longitudinal analyses in a subcohort of male COVID-19 patients identified serum testosterone trajectories as the strongest predictor of survival (AUC of ROC = 92.8%, p < 0.0001) in these patients among all biochemical parameters studied, including single-point admission serum testosterone values. In lethal cases, longitudinal determinations of serum luteinizing hormone (LH) and androstenedione levels did not follow physiological feedback patterns. Failure to reinstate physiological testosterone levels was associated with evidence of impaired T helper differentiation and augmented circulating classical monocytes. CONCLUSIONS: Recovery or failure to reinstate testosterone levels is strongly associated with survival or death, respectively, from COVID-19 in male patients. Our data suggest an early inhibition of the central LH-androgen biosynthesis axis in a majority of patients, followed by full recovery in survivors or a peripheral failure in lethal cases. These observations are suggestive of a significant role of testosterone status in the immune responses to COVID-19 and warrant future experimental explorations of mechanistic relationships between testosterone status and SARS-CoV-2 infection outcomes, with potential prophylactic or therapeutic implications.

Endotoxin and Cytokine Sequential Hemoadsorption in Septic Shock and Multi-Organ Failure.

The mortality of septic shock remains high [Ann Intensive Care. 2017;7:19], so apart from usual therapy based on source control and antibiotics, some patients may need rescue therapies. Blood purification systems may play a role by facilitating the nonspecific removal of inflammatory mediators and microbiological toxins. There are different hemoadsorption systems, we describe in this case report the sequential use of Polymyxin B (PMX) endotoxin-adsorbing column (Toraymixin PMX-20R; Toray, Tokyo, Japan) and Cytosorb® (Cytosorbents Corp., New Jersey, USA).

Headache: A striking prodromal and persistent symptom, predictive of COVID-19 clinical evolution.

OBJECTIVE: To define headache characteristics and evolution in relation to COVID-19 and its inflammatory response. METHODS: This is a prospective study, comparing clinical data and inflammatory biomarkers of COVID-19 patients with and without headache, recruited at the Emergency Room. We compared baseline with 6-week follow-up to evaluate disease evolution. RESULTS: Of 130 patients, 74.6% (97/130) had headache. In all, 24.7% (24/97) of patients had severe pain with migraine-like features. Patients with headache had more anosmia/ageusia (54.6% vs. 18.2%; p < 0.0001). Clinical duration of COVID-19 was shorter in the headache group (23.9 ± 11.6 vs. 31.2 ± 12.0 days; p = 0.028). In the headache group, IL-6 levels were lower at the ER (22.9 (57.5) vs. 57.0 (78.6) pg/mL; p = 0.036) and more stable during hospitalisation. After 6 weeks, of 74 followed-up patients with headache, 37.8% (28/74) had ongoing headache. Of these, 50% (14/28) had no previous headache history. Headache was the prodromal symptom of COVID-19 in 21.4% (6/28) of patients with persistent headache (p = 0.010). CONCLUSIONS: Headache associated with COVID-19 is a frequent symptom, predictive of a shorter COVID-19 clinical course. Disabling headache can persist after COVID-19 resolution. Pathophysiologically, its migraine-like features may reflect an activation of the trigeminovascular system by inflammation or direct involvement of SARS-CoV-2, a hypothesis supported by concomitant anosmia.

Age-specific pediatric reference ranges for immunoglobulins and complement proteins on the Optilite™ automated turbidimetric analyzer.

BACKGROUND: Measurement of immunoglobulins and complement proteins are frontline tests used in the assessment of immune system integrity, and reference values can vary with age. Their measurement provides an insight into the function of the innate and adaptive immune systems. METHODS: We generated pediatric reference ranges for IgG, IgA, IgM, IgD, the IgG and IgA subclasses, and C3 and C4 using the Optilite™ turbidimetric analyzer. RESULTS: The concentrations of IgG, IgA, and IgD showed an increase with age, as expected, while IgM remained stable between the age groups. For the IgG subclasses, no significant differences were observed in IgG1 or IgG3, while IgG2 and IgG4 concentrations increased steadily with age. The concentration of IgG2 plateaued at 15-18 years, while IgG4 plateaued at 10-14 years. The trend of concentrations across all groups was IgG1 > IgG2 > IgG3 > IgG4. For both IgA1 and IgA2, concentrations increased significantly with age, plateauing at 15-18 years. The median IgA1 concentration was greater than IgA2 across all groups. There was a good correlation between the total IgG or IgA concentration and summation of their subclasses (R2  = 0.89, P < .0001, slope y = 0.98x + 14.51 mg/dL and R2  = 0.91, P < .0001, slope y = 1.35x-3.28 mg/dL, respectively). The concentration of C3 and C4 remained stable across the groups, with no significant differences observed. CONCLUSION: We have generated age-specific reference ranges in healthy children for C3, C4, IgG, IgA, IgM, IgD and the IgG and IgA subclasses using the Optilite™ turbidimetric analyzer. These ranges will help identify individuals with abnormal concentrations, thus will aid in the diagnosis of both primary and secondary immunological disorders.

Early Versus Late Diagnosis of Complement Factor I Deficiency: Clinical Consequences Illustrated in Two Families with Novel Homozygous CFI Mutations.

The complement system is an important effector arm of innate immunity and plays a crucial role in the defense against common pathogens. But effective defense and maintenance of homeostasis requires a careful balance between complement activation and regulation. Factor I (FI) is one of the most important regulators of the complement system. Complete FI deficiency is a rare autosomal recessive disorder typically resulting in severe, recurrent infection by encapsulated bacteria. In the present study, we describe two patients from unrelated families with complete FI deficiency diagnosed at very different ages: Patient 1 is a 60-year-old man who had experienced several severe infections (pneumonia, meningitis, sepsis) since childhood, one of which caused significant and permanent neurologic sequelae. In contrast, patient 2 was diagnosed at the age of 4 years after a single infectious episode (otitis media) and through detection of a flat beta2 peak on serum protein electrophoresis. This early diagnosis of FI deficiency enabled prompt implementation of a therapeutic intervention consisting of vaccination with encapsulated bacteria and prophylactic antibiotics. The two patients had novel homozygous mutations in the CFI gene (p.Gly162Asp and p.His380Arg) that disrupted protein function. Interestingly, p.His380Arg is the first mutation described affecting a residue of the highly conserved FI catalytic triad (His380, Asp429, and Ser525). This study illustrates the importance of early versus late diagnosis of FI deficiency and, in general, highlights the clinical relevance of prompt detection of complement system deficiencies.

Novel Mutations Causing C5 Deficiency in Three North-African Families.

The complement system plays a central role in defense to encapsulated bacteria through opsonization and membrane attack complex (MAC) dependent lysis. The three activation pathways (classical, lectin, and alternative) converge in the cleavage of C5, which initiates MAC formation and target lysis. C5 deficiency is associated to recurrent infections by Neisseria spp. In the present study, complement deficiency was suspected in three families of North-African origin after one episode of invasive meningitis due to a non-groupable and two uncommon Meningococcal serotypes (E29, Y). Activity of alternative and classical pathways of complement were markedly reduced and the measurement of terminal complement components revealed total C5 absence. C5 gene analysis revealed two novel mutations as causative of the deficiency: Family A propositus carried a homozygous deletion of two adenines in the exon 21 of C5 gene, resulting in a frameshift and a truncated protein (c.2607_2608del/p.Ser870ProfsX3 mutation). Families B and C probands carried the same homozygous deletion of three consecutive nucleotides (CAA) in exon 9 of the C5 gene, leading to the deletion of asparagine 320 (c.960_962del/p.Asn320del mutation). Family studies confirmed an autosomal recessive inheritance pattern. Although sharing the same geographical origin, families B and C were unrelated. This prompted us to investigate this mutation prevalence in a cohort of 768 North-African healthy individuals. We identified one heterozygous carrier of the p.Asn320del mutation (allelic frequency = 0.065 %), indicating that this mutation is present at low frequency in North-African population.

Identification and characterization of a novel splice site mutation in the SERPING1 gene in a family with hereditary angioedema.

Hereditary angioedema due to C1-inhibitor deficiency (HAE-C1INH) is a rare autosomal-dominant disease caused by mutations in SERPING1 gene. The main clinical feature of C1INH deficiency is the spontaneous edema of the subcutaneous and submucosal layers. More than 280 different mutations scattering the entire SERPING1 gene have been reported. We identified and characterized a new mutation in SERPING1 gene in a Spanish family with hereditary angioedema. The mutation (c.685 + 2 T > A) disrupts the donor splice site of intron 4 leading to the loss of exon 4 in mutant mRNA. We demonstrated that mutant mRNA is mostly degraded, probably by the surveillance pathway no-go mRNA decay. Bioinformatic analysis showed that the mutant protein, if produced, would be non-functional since the protein lacks a stretch of 45 amino acids affecting the functional RCL loop. Finally, we found a reduction of the wild-type mRNA expression in c.685 + 2 T > A carriers.

A novel splice site mutation in the SERPING1 gene leads to haploinsufficiency by complete degradation of the mutant allele mRNA in a case of familial hereditary angioedema.

Hereditary angioedema due to C1-inhibitor deficiency (HAE-C1INH) is a rare autosomal-dominant and life-threatening disorder caused by mutations in SERPING1 gene. It is characterized by attacks of angioedema involving the skin and/or the mucosa of the upper airways, as well as the intestinal mucosa. Here we report the case of a patient with HAE-C1INH without family history of angioedema. By sequencing the SERPING1 gene we detected a novel mutation (c.1249 + 5G > A) affecting the 5' donor splice site in intron 7. We analyzed the SERPING1 cDNA expecting a defect in splicing process but only the wild type allele was detected. SNP analysis of the cDNA sequence demonstrated that only one of the two alleles was present, indicating that the mRNA from the mutated allele was completely degraded. This study reinforces the concept of incomplete penetrance of this disorder since the patients' mother never presented any sign of angioedema despite carrying the same mutation.