Recurrent macrophage activation syndrome (MAS) is very rare. We present the case of an adolescent boy with human leukocyte antigen (HLA) B27-positive ankylosing spondylitis (AS), who experienced episodes of recurrent MAS since he was a toddler. A 16-year-old boy was admitted because of remittent fever with pancytopenia and splenomegaly after surgical intervention for an intractable perianal abscess. He had been...

Varicella-zoster virus infection can lead to severe illness in immunocompromised patients. Further the mortality rate of disseminated varicella infection is extremely high particularly in immunocompromised children. We report a case of disseminated varicella infection in a child with acute lymphoblastic leukemia who was receiving chemotherapy, but was initially admitted with only for acute abdominal pain. The patient rapidly developed severe...

Hemorrhagic cystitis is a common stem cell transplantation-related complication. The incidence of early-onset hemorrhagic cystitis, which is related to the pretransplant conditioning regimen, has decreased with the concomitant use of mesna and hyperhydration. However, late-onset hemorrhagic cystitis, which is usually caused by the BK virus, continues to develop. Although the BK virus is the most common pathogenic microorganism of poststem...

Pyogenic liver abscess (PLA) is rare in healthy children. We report a case of PLA in an immunocompetent 12-year-old boy. Percutaneous catheter drainage was performed for the abscess. In addition, parenteral antibiotics were administered for 3 weeks. Klebsiella pneumoniae was detected in the culture of blood and drained fluid. Here, we present this case and a brief review of the...

Kikuchi-Fujimoto disease (KFD) is a benign self-limiting disease characterized by fever and lymphadenitis. The etiology and pathogenesis of KFD is unclear. However, two hypotheses have been suggested: a viral infection hypothesis and an autoimmune hypothesis. Several KFD patients with various types of autoimmune diseases have been reported, and these reports support the hypothesis for autoimmune pathogenesis of KFD. Here, we...

Listeria monocytogenes is a facultative anaerobic, gram-positive bacillus that is isolated from the soil, vegetables, and wild or domestic animals. Listeria occurs predominantly in the elderly, immunocompromised patients, pregnant women and newborns. Infections by this microorganism are rare in healthy infants and children. L. monocytogenes may cause meningitis, meningoencephalitis, brain abscess, pyogenic arthritis, osteomyelitis, and liver abscesses in children. The...