Alkaline phosphatase in pediatric patients with genu varum caused by vitamin D-deficient rickets.

An elevated serum alkaline phosphatase (ALP) level is one of the markers for the presence of rickets in children, but it is also associated with bone formation. However, its role in diagnosing genu varum in pediatric patients with vitamin D-deficient rickets is still unknown. To clarify the role of the serum ALP level in assessing the severity of genu varum, we retrospectively investigated this issue statistically using data on rickets such as serum intact parathyroid hormone (iPTH), 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, ALP, the level of creatinine as the percentage of the median according to age (%Cr), and the metaphyseal diaphyseal angle (MDA) in the lower extremities as an index of the severity of genu varum. A multiple regression analysis revealed that log ALP and %Cr values were negatively associated with MDA values. The former association was also confirmed by a linear mixed model, while iPTH was positively associated with MDA by path model analysis. To elucidate the association of ALP with MDA in the presence of iPTH, we investigated three-dimensional figures by neural network analysis. This indicated the presence of a biphasic association of ALP with MDA: the first phase increases while the second decreases MDA. The latter phenomenon is considered to be associated with the increase in bone formation due to the mechanical stress loaded on the lower extremities. These findings are important and informative for pediatricians to understand the significance of the serum ALP level in pediatric patients with genu varum caused by vitamin D deficiency.

Structure equation model and neural network analyses to predict coronary artery lesions in Kawasaki disease: a single-centre retrospective study.

A new method to predict coronary artery lesions (CALs) in Kawasaki disease (KD) was developed using a mean structure equation model (SEM) and neural networks (Nnet). There were 314 admitted children with KD who met at least four of the six diagnostic criteria for KD. We defined CALs as the presence of a maximum z score of ≥ 3.0. The SEM using age, sex, intravenous immunoglobulin resistance, number of steroid pulse therapy sessions, C-reactive protein level, and urinary ß2-microglobulin (u-ß2MG/Cr) values revealed a perfect fit based on the root mean square error of approximation with an R2 value of 1.000 and the excellent discrimination of CALs with a sample score (SS) of 2.0 for a latent variable. The Nnet analysis enabled us to predict CALs with a sensitivity, specificity and c-index of 73%, 99% and 0.86, respectively. This good and simple statistical model that uses common parameters in clinical medicine is useful in deciding the appropriate therapy to prevent CALs in Japanese KD patients.

Urinary ß2-microglobulin as an early marker of infantile enterovirus and human parechovirus infections.

Enterovirus and human parechovirus (HPeV) are RNA viruses belonging to the family Picornaviridae that frequently infect infants. These infections show a wide variety of clinical manifestations, from mild to severe. However, there are no known early clinical markers for diagnosis and prediction of disease severity. The aim of this study was to examine the clinical utility of urinary beta 2-microglobulin (ß2MG) for the early detection and prognosis of infantile enterovirus and HPeV infections.This retrospective study included 108 full-term infants younger than 60 days of age, including 15 with enterovirus or HPeV-3 (enterovirus/HPeV-3), 22 with respiratory syncytial virus (RSV), and 24 with bacterial infections. Laboratory data and clinical characteristics were compared among these 3 groups. Of the 15 patients with enterovirus/HPeV-3, 6 were treated with intravenous immunoglobulin (IVIG subgroup) because of severe clinical conditions.Urinary ß2MG to creatinine ratio (ß2MG/Cr) was significantly higher in the enterovirus/HPeV-3 group compared to bacterial and RSV infection groups (both P < .001). In the enterovirus/HPeV-3 group, mean peak urinary ß2MG/Cr was observed on day 1 or 2. Urinary ß2MG/Cr values were significantly higher in the IVIG subgroup than the non-IVIG subgroup (P < .001).Increased urinary ß2MG/Cr in early-stage infection may be a useful clinical marker for the detection and prediction of infantile enterovirus and HPeV infection severity.

Marked elevation of urinary ß2-microglobulin in patients with reversible splenial lesions: A small case series.

The magnetic resonance imaging findings of reversible isolated lesions with transiently reduced diffusion in the splenium of corpus callosum of patients with a wide spectrum of pathological conditions are referred to as reversible splenial lesion syndrome (RESLES). Clinically mild encephalitis/encephalopathy with a reversible splenial lesion (MERS) is probably included within the spectrum of RESLES; however, its exact pathophysiology is not known. Here, we describe three patients with MERS and one patient with RESLES, all of whom showed elevated urinary ß2-microglobulin regardless of diagnosis and presence of pathogens. Elevated urinary ß2-microglobulin suggested that an excessive immune response might play a role in the pathophysiology of reversible splenial lesions.