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.

Lymphomatoid Papulosis Development in Acute Lymphoblastic Leukemia.

Lymphomatoid papulosis (LyP) is a chronic, recurrent benign skin disease characterized by histological features of a CD 30-positive cutaneous T-cell lymphoproliferative disorder. It is rare, with an annual, worldwide incidence of 1.2 - 1.

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.

Atypical Familial Mediterranean Fever in a Japanese Boy with Heterozygous 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 () gene abnormality. FMF can be categorized as typical or atypical, based on clinical findings and genetic screening.