[Sjögren's syndrome with MALT (mucosa-associated lymphoid tissue) lymphoma in a 13-year-old girl: a case report].

We report A case of Sjögren's syndrome complicated with MALT (mucosa-associated lymphoid tissue lymphoma) in childhood. Additionally, Helicobacter pylori infection into the gastric mucosa was highly suspected in this case. A 13-year-old girl suffering from multiple joint pain had received treatment as Juvenile Rheumatic Arthritis with no clinical improvement until introduction to our hospital. On admission to our hospital, high levels of serum anti-SSA and anti-SSB (80.2 and 16.1 holds, respectively) were detected. Minor salivary gland biopsy showed a typical histological finding for Sjögren's syndrome as infiltrating lymphocytes around the excretory ducts. Computed tomography and 67Gallium scintigraphy showed a gastric tumor, and it was diagnosed as primary gastric B-cell MALT lymphoma by the histopathological findings. Additionally, Helicobacter pylori infection into the gastric mucosa was highly suspected. Recently it is emphasized that infection of Helicobacter pylori is related with gastric MALT lymphoma. There has been no reports of children who have Sjögren's syndrome associated with malignant lymphoma. Taken together, Helicobacter pylori infection superimposed with Sjögren's syndrome might accelerate clinical course in our particular case.