Undulating tubules in lymphocytes of an apparently healthy human donor

So-called 'undulating tubules' were found in the blood lymphocytes of an apparently healthy 33-year-old male. Undulating tubules have been noted to occur frequently in kidney cells and blood lymphocytes of patients suffering from collagen diseases and especially from SLE. They have been suggested to be a possibly pathognomonic finding in such diseases. Our result seems to contradict such an association.