A One-Year-Old Girl With Human Parvovirus B19 Infection and Hypocomplementemia Mimicking Incomplete Kawasaki Disease.

Human parvovirus B19 (B19) is a single-stranded DNA virus that targets erythroid progenitor cells in the bone marrow. B19 causes erythema infectiosum in children, transient aplastic anemia, pure red cell aplasia, hydrops fetalis, and contributes to other illnesses. An association between B19 infection and hypocomplementemia and rheumatoid arthritis has been reported, but the underlying mechanisms remain unclear. We report the case of a 1-year-old Japanese girl with persistent fever, skin rash, transient edema of the extremities, hypoalbuminemia, and hypocomplementemia associated with B19 infection. We considered Kawasaki disease (KD) and collagen diseases, particularly systemic lupus erythematosus, in our differential diagnosis. B19 infection might be associated with serological features that suggest systemic lupus erythematosus and may present with clinical symptoms seen in KD. Especially during erythema infectiosum epidemics, we must consider B19 infection in the differential diagnosis of KD patients who demonstrate atypical clinical symptoms and unexplained laboratory findings.

An Immunoglobulin A Vasculitis Case Without Skin Symptoms Complicated With Severe Abdominal Symptoms.

Immunoglobulin A vasculitis (IgAV) primarily affects childhood and can be categorized as immune complex vasculitis. It typically presents with purpura, abdominal pain, arthritis, and nephritis. IgAV can be diagnosed without hesitation when the characteristic skin lesions appear at onset; however, in cases where the abdominal symptoms precede the skin rash or there is no purpura at all, diagnosis can be challenging. Delayed diagnosis of IgAV may be associated with serious abdominal complications, such as gastrointestinal perforation. Here, we describe a girl with IgAV complicated with severe abdominal symptoms and lacking purpura. Despite this lack, the patient's elevated levels of D-dimer and C-reactive protein (CRP), suggestive of vasculitis, and localized small bowel intestinal wall thickening suggested IgAV. After administration of steroids relieved the abdominal symptoms and hypoalbuminemia, treatment was discontinued. Given the limited reports of patients with IgAV complicated with severe abdominal symptoms and no skin symptoms, the diagnosis and management process remains unclear. Therefore, it is imperative to consider IgAV as a differential diagnosis in patients with severe abdominal symptoms. Furthermore, we suggest checking D-dimer, CRP, and coagulation factor XIII activity levels in these patients.

The impact of the coronavirus disease 2019 pandemic on pediatric hospitalization in Kitami, Japan.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has drastically changed the recommended activities and environment for patients worldwide. Our aim was to assess the impact of COVID-19 on pediatric hospitalizations in Kitami, Japan. METHODS: A retrospective, single-center study was conducted on hospitalized patients aged 0-14 years at the Japanese Red Cross Kitami Hospital. We compared the incidence of pediatric patients hospitalized in 2020 with those in 2017-2019. RESULTS: The number of pediatric hospitalized patients dropped significantly in 2020 compared to that in 2017-2019 (median 43.0 vs 78.5 per month, P < 0.001). The patients were significantly older in 2020 (4.3 vs 3.4 years, P < 0.001). Hospitalization from respiratory (8.5 vs 30.5, P < 0.001) and gastrointestinal infections (3.0 vs 6.0, P = 0.004) significantly decreased. Admission due to respiratory syncytial virus (0.0 vs 4.0, P < 0.001), human metapneumovirus (0.0 vs 1.0, P = 0.005), influenza (0.0 vs 0.0, P = 0.009), adenovirus (0.0 vs 1.0, P = 0.003), and rotavirus infection (0.0 vs 0.0, P = 0.025) also decreased significantly. The <1-5 age groups significantly decreased (<1 year old, 6.5 vs 12.5, P < 0.001; 1-3 years old, 13.0 vs 29.5, P < 0.001; 4-5 years old, 5.5 vs 11.5, P < 0.001). Hospitalization due to foreign body ingestions increased significantly in 2020 (1.0 vs 0.0, P = 0.010). CONCLUSIONS: The COVID-19 control measures inadvertently reduced the number of hospitalized pediatric patients, especially younger children with respiratory and gastrointestinal infections.

Atypical Familial Mediterranean Fever in a Japanese Boy with Heterozygous MEFV p.Ser503Cys Exon 5 Variant.

Periodic fever syndromes are heterogeneous diseases. Familial Mediterranean fever (FMF) is one of the hereditary periodic fever diseases caused by a Mediterranean fever (MEFV) gene abnormality. FMF can be categorized as typical or atypical, based on clinical findings and genetic screening. Atypical FMF has a wide variation of clinical findings and disease-causing mutations of MEFV. Therefore, it is sometimes difficult to diagnose an unknown fever as FMF. To date, a large number of various typical and atypical FMF cases have been reported in Japan. Here, we describe a Japanese boy with heterozygous MEFV p.Ser503Cys exon 5 variant who developed periodic fever. He was treated with colchicine; a complete eradication of his fever and various accompanying symptoms have been subsequently achieved for more than a year. Given that there have been a few reports about patients with this variant, little is known about the genetic and phenotypic role of heterozygous MEFV p.Ser503Cys exon 5 variant. It is therefore imperative to consider atypical FMF as a differential diagnosis when a periodic fever is encountered. Furthermore, we suggest that it is worthwhile to integrate MEFV gene analysis with the potential effects of colchicine treatment in patients with periodic fever.

Diagnostic dilemma in a case of obstructive sleep apnoea syndrome with reversible pulmonary hypertension and right heart failure: A case report.

Childhood obstructive sleep apnoea syndrome (OSAS) secondary to adenoid hyperplasia is known to give rise to pulmonary hypertension. However, we present a case of a toddler with pulmonary hypertension (PH) and right heart failure due to OSAS, the cause of which is difficult to identify. After the patient underwent an adenotonsillectomy, OSAS disappeared and the PH eventually resolved. Both paediatricians and otolaryngologists should know that paediatric OSAS can occur even in the setting of mild, clinically insignificant palatine tonsil hypertrophy and adenoid hyperplasia. Surgical intervention should be considered without losing the opportunity if it could be the cause of PH.

Electrochemical selective detection of uric acid using a copper-modified carbon electrode.

The uric acid (UA) level in (human) serum is an important indicator of several diseases; however, its electrochemical detection is difficult because the oxidation potentials of UA and ascorbic acid (AA) are very close. In this study, we have developed a simple and efficient UA detection method using a copper-modified carbon electrode. The detection principle is based on the selective oxidation of AA by Cu(II), wherein Cu(II) reacts selectively with AA but not with UA. By performing this specific reaction on an electrode surface, we have successfully distinguished the oxidation potential of UA without AA interference.

Electrochemical detection of E. coli 16S rDNA sequence using air-plasma-activated fullerene-impregnated screen printed electrodes.

A new DNA modified electrode for the electrochemical detection of 16S rDNA extracted from Escherichia coli (JCM1649) is proposed. The electrodes were fabricated by screen printing a fullerene-impregnated carbon ink onto a poly(methylmethacrylate) substrate and immobilizing a probe DNA on the surface after activating the electrode with air plasma. The results indicated a dramatic improvement in the surface coverage of the immobilized probe DNA, and of the reduction peak of the redox indicator (Co(phen)(3)(3+)) due to the incorporation of fullerene. By immobilizing the probe onto the fullerene-impregnated screen-printed electrodes, the PCR product of the 16S rDNA extracted from E. coli was directly detected without any pretreatment. A well defined signal difference was observed between the perfectly matching oligonucleotide and the mismatching one, and it was possible to detect the target at the modified electrode. This method enabled us to clearly detect the two base mismatches in the ca. 1500-bases long 16S rDNA sequence.