Novel SLC30A2 mutations in the pathogenesis of transient neonatal zinc deficiency.

Importance: Transient neonatal zinc deficiency (TNZD) occurs in breastfed infants due to abnormally low breast milk zinc levels. Mutations in the solute carrier family 30 member 2 (SLC30A2) gene, which encodes the zinc transporter ZNT2, cause low zinc concentration in breast milk. Objective: This study aimed to provide further insights into TNZD pathophysiology. Methods: SLC30A2 sequencing was performed in three unrelated Japanese mothers, whose infants developed TNZD due to low-zinc milk consumption. The effects of the identified mutations were examined using cell-based assays and luciferase reporter analysis. Results: Novel SLC30A2 mutations were identified in each mother. One harbored a heterozygous missense mutation in the ZNT2 zinc-binding site, which resulted in defective zinc transport. The other two mothers exhibited multiple heterozygous mutations in the SLC30A2 promoter, the first mutations in the SLC30A2 regulatory region reported to date. Interpretation: This report provides new genetic insights into TNZD pathogenesis in breastfed infants.

Usefulness of Q-Probe PCR in Detecting Macrolide-Resistant Mycoplasma pneumoniae Infection in Children.

To investigate the usefulness of quenching probe polymerase chain reaction (Q-probe PCR) for the detection of macrolide-resistant Mycoplasma pneumoniae (MP), we retrospectively analyzed the clinical course of 21 children with MP infection. The rate of macrolide-resistant MP was 66.7%. The duration of pyrexia after the initial antibiotic treatment was longer in patients with macrolide-resistant MP infection than in those with macrolide-sensitive MP infection. The duration of pyrexia after Q-probe PCR was not significantly different between patients with macrolide-resistant and -sensitive MP infection. Antibiotic use based on qPCR may reduce the duration of pyrexia. Q-probe PCR is useful in determining the appropriate antibiotics and improves the clinical course of MP infections.

Serum free carnitine levels in children with Kawasaki disease.

BACKGROUND: Carnitine plays an essential role in the transfer of long-chain fatty acids to the mitochondria for ß-oxidation. No study has characterized carnitine in children with Kawasaki disease (KD). The objective of this study was to elucidate the characteristics of serum free carnitine (FC) in hospitalized pediatric patients with KD. METHODS: We retrospectively analyzed 45 patients with KD in whom serum FC levels were measured. We investigated the clinical and laboratory parameters before intravenous immunoglobulin was administered, including serum FC levels, according to the response to intravenous immunoglobulin (IVIG). We also analyzed the relationship among serum FC, laboratory data, and clinical variables. RESULTS: IVIG was effective in 33 children (responders) and was ineffective in 12 children (non-responders). Serum FC levels were higher in non-responders than in responders: 35.3 µmol/L (range, 26.8-118.4 µmol/L) vs 31.4 µmol/L (range, 20.9-81.2 µmol/L), P <0.05. FC levels before IVIG in 80% of responders were below the normal range. The levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin, and FC were higher in non-responders than in responders. FC levels were correlated with AST (R2 = 0.364, P = 0.0015) and ALT (R2 = 0.423, P < 0.001) levels. CONCLUSIONS: Free carnitine levels were elevated in some patients with KD, especially in those who were refractory to IVIG. Additionally, FC levels in children with KD correlated with ASL and ALT levels.

Usefulness of brain natriuretic peptide to distinguish Kawasaki disease from cervical lymphadenitis.

BACKGROUND: Cervical lymphadenitis (CL) cannot be easily distinguished from Kawasaki disease (KD). We therefore explored whether brain natriuretic peptide (BNP) levels are useful in this context. METHODS: We retrospectively analyzed 14 children with CL and 177 children with KD. Patients with KD were divided into three groups according to their clinical symptoms at hospitalization - 97 patients had typical KD, 35 had node-first KD (NFKD), and 45 had KD without lymphadenopathy. We reviewed data on clinical and laboratory parameters, including serum BNP levels, at hospitalization together with factors that might distinguish KD from CL. RESULTS: Patients with CL were older than those with KD. Serum BNP levels were higher in all the KD groups than in the CL group. Multivariate logistic regression analyses indicated that higher BNP levels were associated with NFKD (odds ratio: 1.12, 95% confidence interval: 1.01-1.25). The receiver operating characteristic curve yielded a BNP cutoff of 18.3 pg/mL, with a sensitivity of 0.680, a specificity of 0.857, and an area under the curve of 0.806 (95% confidence interval: 0.665-0.947). CONCLUSIONS: Serum BNP levels can be used to distinguish KD from CL, especially in patients with NFKD.

Insulin-like growth factor-1 level is a poor diagnostic indicator of growth hormone deficiency.

We evaluated the diagnostic accuracy of insulin-like growth factor-1 (IGF-1) for screening growth hormone deficiency (GHD) to determine the usefulness of IGF-1 as a screening test. Among 298 consecutive children who had short stature or decreased height velocity, we measured IGF-1 levels and performed growth hormone (GH) secretion test using clonidine, arginine, and, in cases with different results of the two tests, L-dopa. Patients with congenital abnormalities were excluded. GHD was defined as peak GH ≤ 6.0 ng/mL in the two tests. We identified 60 and 238 patients with and without GHD, respectively. The mean IGF-1 standard deviation (SD) was not significantly different between the GHD and non-GHD groups (p = 0.23). Receiver operating characteristic curve analysis demonstrated the best diagnostic accuracy at an IGF-1 cutoff of - 1.493 SD, with 0.685 sensitivity, 0.417 specificity, 0.25 positive and 0.823 negative predictive values, and 0.517 area under the curve. Correlation analysis revealed that none of the items of patients' characteristics increased the diagnostic power of IGF-1. IGF-1 level had poor diagnostic accuracy as a screening test for GHD. Therefore, IGF-1 should not be used alone for GHD screening. A predictive biomarker for GHD should be developed in the future.

Methylprednisolone-induced anaphylaxis diagnosed by intradermal skin test: a case report.

BACKGROUND: Glucocorticoids rarely cause anaphylaxis. Common methods for the determination of allergens include in vivo skin prick test (SPT) and intradermal skin test (IDST) and the in vitro basophil activation test (BAT). However, to our knowledge, the best strategy for diagnosing glucocorticoid-induced anaphylaxis has not been elucidated. CASE PRESENTATION: A 10-year-old boy was admitted to our hospital because of 2 weeks of fever and arthralgia. He had not been treated with glucocorticoids before, including methylprednisolone (mPSL). He was suspected to have bacterial myositis and was treated with ceftriaxone. However, his symptoms persisted for > 2 weeks. Autoinflammatory arthritis was suspected, and he was treated with mPSL sodium succinate (MPS) pulse therapy (30 mg/kg). After 15 min of mPSL injection, he had wheezing and generalized wheal formation with decreased oxygen saturation. As anaphylaxis was suspected, mPSL was discontinued, and olopatadine and oxygen were administered. The symptoms improved considerably without the use of epinephrine and disappeared in 30 min. One month after discharge, SPT, IDST, and BAT were performed without discontinuing his prescribed oral prednisolone. SPTs for MPS, hydrocortisone sodium succinate (HCS), prednisolone sodium succinate (PSS), dexamethasone sodium phosphate (DSP), and betamethasone sodium phosphate (BSP) were negative. IDSTs for MPS, HCS, and PSS were positive, whereas those for DSP and BSP were negative. By contrast, BATs for MPS, HCS, and PSS were negative. Although glucocorticoid-induced hypersensitivity caused by nonmedicinal ingredients such as lactose, carboxymethylcellulose, polyethylene glycol, and hexylene glycol has been reported; the glucocorticoids tested in this patient did not contain any of these nonmedicinal ingredients. As the glucocorticoids that were positive on IDST share a succinate ester, this might have caused MPS-induced anaphylaxis. CONCLUSIONS: We report the case of MPS-induced anaphylaxis diagnosed by IDST but not BAT. In case reports of glucocorticoid-induced anaphylaxis in the literature, most patients were diagnosed with SPT or IDST. These results suggest that BAT should be considered when IDST and SPT are negative. Further studies are necessary to clarify the best strategy for diagnosing glucocorticoid-induced anaphylaxis.

Increased Pentraxin 3 Levels Correlate With IVIG Responsiveness and Coronary Artery Aneurysm Formation in Kawasaki Disease.

Kawasaki disease (KD) is a febrile disease of childhood characterized by systemic vasculitis that can lead to coronary artery lesions (CAL). This was a prospective cohort study to determine the levels of the pentraxin 3 (PTX3), soluble CD24-Subtype (Presepsin) and N-terminal pro-brain natriuretic peptide (NT-pro BNP) in consecutive KD patients. From January 2013 to March 2015, all patients with KD admitted to Aichi Medical University Hospital who provided consent had their plasma saved before IVIG administration. In total, 97 cases were registered. 22 cases of incomplete KD were excluded from the outcome analysis. The total 75 cases were used for statistical analyses. A PTX3 threshold of >7.92 ng/ml provided a specificity of 88.5 %, a sensitivity of 94.4 %, and a likelihood ratio as high as 15.92 for the diagnosis of KD compared with febrile non-KD controls. Although an echocardiographic diagnosis of CAL in the early course of the disease was confirmed in 24 cases, it was not in the remaining 51 cases. Neither NT-proBNP nor Presepsin had statistical significance for the prediction of the echocardiographic CAL diagnosis. Only PTX3 was significantly predictive of the echocardiographic CAL diagnosis (p=0.01). The PTX3 level was significantly higher in the intravenous immunoglobulin (IVIG) non-responders (45.9±7.45) than in the IVIG responders (17.0 ± 1.46 ng/ml) (p< 0.001). The PTX3 level also correlated with the number of IVIG treatment courses needed to resolve fever (R² =0.64). Persistent CAL (pCAL) formation was observed in three cases; one of aneurysm only and two aneurysms with dilatations. The patients with pCAL had significantly higher PTX3 levels (85 ± 8.4 ng/ml) than patients without pCAL (22 ± 2.2 ng/ml) (p< 0.0001). In terms of pCAL prediction, the area under the curve (AUC) of receiver operating characteristic ROC curve of PTX3 was 0.99, and it was significantly greater than that of Presepsin (0.67) or NT-proBNP (0.75). PTX3 is a soluble pattern recognition molecule that acts as a main component of the innate immune system. These data suggest that PTX3 can be utilized as a definitive biomarker for the prediction of IVIG resistance and subsequent CAL formation in patients with KD.

Odontohypophosphatasia treated with asfotase alfa enzyme replacement therapy in a toddler: a case report.

Hypophosphatasia (HPP) is a rare skeletal disorder caused by loss-of-function mutations in Alkaline Phosphatase, Biomineralization associated (ALPL) gene that encodes tissue-nonspecific alkaline phosphatase. Odontohypophosphatasia (odonto-HPP), a mild form of HPP, is characterized only by oral manifestations including premature exfoliation of deciduous teeth. Enzyme replacement therapy (ERT) is effective in severe HPP cases; however, information about its efficacy for odonto-HPP is limited. A 2-yr-old girl was referred to our hospital for mobility of her deciduous teeth with low serum alkaline phosphatase (ALP) level of 253 U/L (reference range: 410-1,150 U/L) and high urine phosphoethanolamine level of 1,419.9 µmol/g·Cre (7-70 µmol/g·Cre). She had no history of bone fractures; however, several members of her family had low serum ALP levels with a history of pathological fractures. She had a novel heterozygous missense mutation (c.1183A>T, p.Ile395Phe) in ALPL, and therefore, was diagnosed with odonto-HPP. After she was provided ERT to prevent premature exfoliation, no tooth mobility was observed. However, two deciduous teeth exfoliated two months after starting ERT, which was possibly triggered by a bout of common cold. Starting ERT following tooth mobility might be relatively late. Previous studies on experimental mice showed that starting ERT at birth may be effective in preventing premature exfoliation of deciduous teeth.

Lung fibroblasts produce IL-33 in response to stimulation with retinoblastoma-binding protein 9 via production of prostaglandin E2.

Intestinal nematode infection induces pulmonary eosinophilia via IL-33, although the mechanism of pulmonary IL-33 induction remains unclear. Because nematode migration damages lungs, we speculated that lung-derived damage-associated molecular patterns (DAMPs) possess an IL-33-inducing activity (IL33ia). Indeed, intra-nasal administration of a lung extract induced IL-33 production in lungs. Additionally, lung extracts increased Il33 mRNA expression in primary lung fibroblasts. Proteomic analysis identified retinoblastoma-binding protein 9 (RBBP9) as a major DAMP with IL33ia. RBBP9 was originally discovered as a protein that provides cells with resistance to the growth inhibitory effect of transforming growth factor (TGF)-ß1. Here, we found that stimulation by RBBP9 induced primary fibroblasts to produce prostaglandin E2 (PGE2) that, in turn, induced fibroblasts to produce IL-33. RBBP9-activated fibroblasts expressed mRNAs of cyclooxygenase-2 (COX-2) and PGE2 synthase-1 that convert arachidonic acid to PGE2. Furthermore, they expressed PGE2 receptors E-prostanoid (EP) 2 and EP4. Thus, treatment with a COX-2 inhibitor or EP2 and/or EP4 receptor antagonists inhibited RBBP9-induced IL-33 production. Nematode infection induced pulmonary Il33 mRNA expression, which was inhibited by the COX-2 inhibitor or EP2 and EP4 antagonists, suggesting that nematode infection induced pulmonary Il33 mRNA via PGE2. RBBP9 was expressed constitutively in the lung in the steady state, which did not increase after nematode infection. Finally, we found that Rbbp9-deficient mice had a significantly diminished capacity to increase pulmonary Il33 mRNA expression following nematode infection. Thus, the PGE2-EP2/EP4 pathway activated by RBBP9 released from damaged lungs is important for pulmonary IL-33 production in nematode-infected animals.

Procalcitonin as a Biomarker of Unresponsiveness to Intravenous Immunoglobulin for Kawasaki Disease.

OBJECTIVE: To investigate the usefulness of procalcitonin (PCT) as predictive factors of intravenous immunoglobulin (IVIG)-resistant Kawasaki disease patients. METHODS: We retrospectively analyzed the laboratory data from 215 children with Kawasaki disease treated with IVIG from 2014 to 2019. We analyzed the clinical and laboratory parameters just before the IVIG including serum levels of PCT with respect to the IVIG response. RESULTS: Eventually, 127 patients were analyzed. The median age was 2.4 years. IVIG was effective in 108 children (responders) and was ineffective in 19 (non-responders). Serum PCT concentration was higher in non-responders than those of responders (P < 0.001). Multivariate logistic regression analyses indicated that higher PCT concentration (odds ratio 1.34, 95% confidence interval 1.10-1.64) were associated with IVIG resistance. Analyses of the receiver operating characteristic curve showed that the cutoff value of PCT 2.18 ng/mL had 46.4% of sensitivity and 93.9% of specificity. Receiver operating characteristic analysis yielded an area under the curve of 0.82 (0.72-0.92) to predict IVIG resistance. CONCLUSIONS: Serum PCT value can be an excellent biomarker for predicting unresponsiveness to IVIG with a good discriminatory ability as well as the existing prediction scores.

White Blood Cell and Neutrophil Counts and Response to Intravenous Immunoglobulin in Kawasaki Disease.

We explored parameters to predicting the efficacy of intravenous immunoglobulin (IVIG) therapy for patients with Kawasaki disease (KD). We retrospectively analyzed the laboratory data of 77 children with KD treated with IVIG. Data obtained before and within 24 hours after IVIG therapy were compared between responders and nonresponders. The white blood cell (WBC) and neutrophil counts were significantly lower in responders than nonresponders within 24 hours after IVIG. The areas under the receiver operating characteristics curves of the WBC and neutrophil counts were 0.846 and 0.754, respectively. The WBC and neutrophil counts differed significantly between responders and nonresponders (the latter developed recurrent pyrexia after transient fever resolution). In conclusion, WBC and neutrophil counts within 24 hours after IVIG usefully predict the efficacy of IVIG therapy for those with KD, and identify nonresponders to such therapy.

A Rare Case of Fetal Onset, Food Protein-Induced Enterocolitis Syndrome.

BACKGROUND: Food protein-induced enterocolitis syndrome (FPIES) is a non-IgE-mediated food allergy. The pathological mechanism of FPIES is intestinal inflammation, and cell-mediated hypersensitivity is presumed to play an important role in its development. CASE REPORT: The first case in which significant fetal intestinal distension suggested fetal onset of FPIES is reported. A 2,334-g male was born at 34 weeks by vaginal delivery. RESULTS: In utero, he had significant intestinal distension on ultrasonography and MRI. A few hours after the first feeding, he produced bloody stool and showed abdominal distension. In this case, FPIES was not only caused by cow's milk protein diagnosed clinically and by an allergen-specific lymphocyte stimulation test, but also by breast milk diagnosed by oral food challenge. The clinical course and laboratory results strongly suggested not only fetal sensitization but also fetal onset. CONCLUSION: This report might be helpful for prompt diagnosis and treatment and, furthermore, lead to elucidation of the pathogenesis and pathophysiology of FPIES.

Fournier's gangrene during ACTH therapy.

Fournier's gangrene is an infectious necrotizing fasciitis of the perineal, genital, or perianal regions and is uncommon in children. Adrenocorticotropic hormone (ACTH) is effective for the treatment of infantile spasms; however, suppression of immune function is one of the major adverse effects of this approach. We encountered a 2-month-old boy with infantile spasms that had been treated with ACTH and had developed complicating Fournier's gangrene. Strangulation of a right inguinal hernia was observed after ACTH treatment. Although surgical repair was successful and no intestinal injuries were detected, swelling and discoloration of the right scrotum developed in association with pyrexia and a severe inflammatory response. A scrotal incision revealed pus with a putrid smell. The patient was subsequently diagnosed with Fournier's gangrene complicated by septic shock and disseminated intravascular coagulation. Extensive debridement and intensive care was performed. Enterobactor aerogenes, methicillin-resistant Staphylococcus aureus, and Enterococcus faecalis were isolated from the pus. Meropenem, teicoplanin, and clindamycin were administered to control the bacterial infection. The patient was discharged from the intensive care unit without any obvious neurological sequelae. Suppression of immune function associated with ACTH therapy may have been related to the development of Fournier's gangrene in this case.

Epithelial-derived nuclear IL-33 aggravates inflammation in the pathogenesis of reflux esophagitis.

BACKGROUND: IL-33 is a new tissue-derived cytokine constitutively expressed in epithelial cells and plays a role in sensing damage caused by inflammatory diseases. The function of IL-33 in the esophageal mucosa has not been previously described. Accordingly, we examined the expression of IL-33 and its role in the pathogenesis of reflux esophagitis (RE). METHODS: IL-33 in the esophageal mucosa of RE patients and in an in vitro stratified normal esophageal squamous epithelial model was examined at the messenger RNA and protein levels. The correlation of the level of IL-33 and IL-8 or IL-6 was examined. Cell layers were stimulated with bile acids and cytokines. IL-33 was knocked down by small interfering RNA (siRNA). Pharmacological inhibitors and signal transducer and activator of transcription 1 (STAT1) siRNA were used. RESULTS: IL-33 was significantly upregulated in RE patients, and was located in the nuclei of basal and suprabasal layers. Upregulated IL-33 messenger RNA expression was correlated with IL-8 and IL-6 expression. In vitro, IL-33 was upregulated in the nuclei of basal and suprabasal layers by interferon-γ (IFNγ), and the upregulation was aggravated by the combination of deoxycholic acid (DCA) and IFNγ. IL-33 knockdown dampened IFNγ- and DCA-induced IL-8 and IL-6 production. IFNγ-induced IL-33 was inhibited by a Janus kinase inhibitor, a p38 mitogen-activated protein kinase inhibitor, and STAT1 siRNA. CONCLUSIONS: Nuclear IL-33 is upregulated in erosive mucosa of RE patients and is correlated with IL-8 and IL-6 levels. The normal esophageal epithelial model enables us to show for the first time that epithelial-cell-derived nuclear but not exogenous IL-33 is located upstream of the production of inflammatory cytokines and can aggravate the inflammation.

The role of basophils and proallergic cytokines, TSLP and IL-33, in cutaneously sensitized food allergy.

Cutaneous sensitization with a food antigen before its consumption elicits the development of food allergy. Here, we report the site- and stage-dependent roles of basophils and proallergic cytokines, thymic stromal lymphopoietin (TSLP) and IL-33, in a mouse model of food allergy initially sensitized cutaneously with the food antigen. Mice were epicutaneously sensitized with the food antigen ovalbumin (OVA) followed by oral challenge with OVA. Epicutaneously sensitized mice produced OVA-specific IgE and developed IgE-dependent anaphylaxis after oral challenge. Basophil-depleted or TSLP-receptor-deficient mice did not produce OVA-specific IgE and were protected from oral challenge-induced anaphylaxis. IL-33-deficient mice produced normal levels of OVA-specific IgE. However, IL-33-deficient mice and mice treated with recombinant soluble IL-33 receptor were protected from anaphylaxis. Thus, basophils and TSLP have pivotal roles in Th2 development in the skin during the sensitization phase of food allergy. In contrast, while IL-33 is dispensable for promoting cutaneous antigen sensitization, the cytokine is essential for inducing IgE-dependent anaphylaxis in the gut.

Contribution of IL-33-activated type II innate lymphoid cells to pulmonary eosinophilia in intestinal nematode-infected mice.

When animals are infected with helminthic parasites, resistant hosts show type II helper T immune responses to expel worms. Recently, natural helper (NH) cells or nuocytes, newly identified type II innate lymphoid cells, are shown to express ST2 (IL-33 receptor) and produce IL-5 and IL-13 when stimulated with IL-33. Here we show the relevant roles of endogenous IL-33 for Strongyloides venezuelensis infection-induced lung eosinophilic inflammation by using Il33(-/-) mice. Alveolar epithelial type II cells (ATII) express IL-33 in their nucleus. Infection with S. venezuelensis or intranasal administration of chitin increases in the number of ATII cells and the level of IL-33. S. venezuelensis infection induces pulmonary accumulation of NH cells, which, after being stimulated with IL-33, proliferate and produce IL-5 and IL-13. Furthermore, S. venezuelensis infected Rag2(-/-) mice increase the number of ATII cells, NH cells, and eosinophils and the expression of IL-33 in their lungs. Finally, IL-33-stimulated NH cells induce lung eosinophilic inflammation and might aid to expel infected worms in the lungs.

Proliferation of sensory C-fibers and subsequent neurogenic inflammation in rat airway induced by inhaled lipopolysaccharide.

Lipopolysaccharide (LPS) is associated with the development and exacerbation of airway inflammation. Increases in innervation of sensory C-fibers and tachykinin receptors, which mainly involve overproduction of neurotrophins such as nerve growth factor (NGF), may enhance neurogenic inflammation. Expression of NGF and its receptors in rat lungs is known to decline with age. We examined whether inhaled LPS causes proliferation of sensory C-fibers, increased expression of tachykinin receptors and subsequent enhancement of neurogenic inflammation in the airways of preweaning rats. Wistar male rats aged 2 weeks inhaled aerosolized LPS derived from Escherichia coli (0.1mg/ml) for 30 min. Evans blue dye leakage into the trachea induced by gaseous formaldehyde or intravenous capsaicin was measured as an index of tachykinin NK1 receptor-mediated vascular permeability. Expression of substance P-immunoreactive nerves, tachykinin NK1 receptors, tumor necrosis factor (TNF)-α and NGF in the trachea was also assessed immunohistochemically. Neurogenic plasma leakage in the trachea increased significantly between 7 and 21 days after LPS inhalation. Expression of TNF-α, NGF, substance P-immunoreactive nerves and tachykinin NK1 receptors was enhanced, peaking at 28 h, 7 days, 14 days and 14 days after LPS inhalation, respectively. Pretreatment with infliximab, a blocking antibody for TNF-α, almost completely abolished the airway changes seen after LPS inhalation. In conclusion, inhaled LPS increased innervation of sensory C-fibers and expression of tachykinin NK1 receptors in the airway, probably resulting in enhancement of neurogenic airway inflammation. These airway responses may be caused by overproduction of neurotrophins including NGF, mainly through a TNF-α-mediated pathway.