Ex juvantibus diagnosis of recurrent granulomatous flexor tenosynovitis: insidious Mycobacterium tuberculosis.

We report a case of recurrent painful and disabling granulomatous flexor tenosynovitis of the right wrist in 50-year-old female patient. The proper diagnosis was made ex juvantibus after repeated cultivation of Mycobacteria yielded negative results and local disease control was surgically unsuccessful. It was then decided to start at first with oral Clarithromycin at 500mg 2x daily during 6-month period throughout which there was no sign of local recurrence. However, synovectomy had to be performed 3 times in total during the period of two years. While the noninfectious causes were excluded, and infectious agent was not to be determined, the decision was made to administer full anti-tuberculosis medication therapy. At about the same time, we were finally able to obtain a positive Mycobacterium tuberculosis culture after a sudden onset of right axillary lymphadenitis, but only two and half years from the occurrence of first symptoms related to right wrist tenosynovitis.