| Chronic hand special infections were common diseases in littoral area of China, which was hard to cure and always had a long course and poor prognoses, and its social impact was huge. In many years there were various standpoints about the pathogen, such as common bacteria, mycobacteria, fungus and norcardiosis. Although many doctors suggested that mycobacterium tuberculosis (MTB) or non-tuberculo-mycobacterium (NTM) were most likely to be the pathogens, there had no systematic domestic study as well as literatures to refer. As a matter of fact, we had little bacteriologic evidence when diagnose. So hand infections caused by NTM were almost entirely unknown in the last 10 years, clinical diagnosis and therapies were carried out according to abroad reference and past experiences. To confirm our assumption that NTM were main pathogens in chronic hand special infections, we performed a series of inspections and germ culture to find out the real pathogen, providing evidence for clinical diagnosis and treatment.Part 1: Germ culture and identification of species in the tissue from chronic hand special infectionsTo explore the etiological factors of chronic hand special infections, and to give evidence for clinical diagnosis as well as treatments, pathologic inspections, Acid-Fast Stain, bacterial culture, mycobacterium culture were performed in all 48 cases of chronic hand special infections in 2002-2005. Isolated mycobacterium was identified through both chemistry and genotype techniques. Most cases showed granulomatous lesions in pathological appearance, 3 positive and 2 suspected in Acid-Fast Stain, 17 positive in special culture: 13 M. marinum, 1 M. tuberculosis, 1 M. fortuitous, 1 M. avium, and 1 M.nonchromogenicum; only 3 positive in common germ culture, 1 Nocardiosis, 1 Staphylococcus epidermis and 1 Alcaligenes xylosoxidans, while the last 2 were mixed-infections with mycobacterium; but no fungus were found in all clinical specimens. As a result, Non-Tuberculo-Mycobacterium (NTM), particularly M. mariunm were far more important factor than tuberculosis and other bacterial in hand special chronic infections.Part 2: PCR/gene sequencing in detecting Mycobacterium from hand special chronic infectionsTo provide direct evidence for clinical therapy, we detected Mycobacterium from 37 fresh tissue specimens of hand special chronic infections by Nested-PCR, and the PCR products were identified by gene sequencing to species level. 15 of 27 culturing negative specimens were positive by Nest-PCR, in which 9 were M.marinum, 2 M.kansasii/Gastri, 2 M.avium, 1 M.chelonae/abscessus and 1TB. 9 of 10 culturing positive specimens were positive by Nest-PCR, in which 6 were M.marinum, 1 M.avium, 1 M.fortuitum and 1TB.Therefore, Nest-PCR was an effective method to detect mycobacterium from both culturing negative and positive specimens. Again NTM were suggested to be the major factor of chronic hand special infections in our study. At the same time we found PCR/gene sequencing may be a good substituent for traditional diagnosis because of its speed.Part3: PCR-reverse dot hybridization assay for detecting mycobacterium from Histopathologic Specimens showed chronic granulomaNTM diseases also showed chronic granuloma in pathological features, with or without Langhans-type giant cells and caseous necrosis, so it is hard to identify between NTM and TB when granuloma was well formed. To investigate the relationship between pathological features and the various species of mycobacteria, we chose 46 formalin-fixed, paraffin-embedded tissue blocks from 46 patients with chronic hand special infections whose pathologic features coincided to chronic granulomas, and used Nested-PCR and reverse blot hybridization assay to detect mycobacteria and identified them into species level. Only 11 of 46 were positive by Nested-PCR, while 10 were identified as mycobacterium, in which 6 M.marinum, 2 M.avium, 1 M.kansassi/gastri and 1TB. Histopathologic findings showed many cross features between TB and NTM, so it is not a suitable method for diagnosis of mycobacterial deseases. Microbiological evidence was still necessary to diagnosis and treatments.Part 4: Antibiotic susceptibilities test of NTM and case-control study between new therapy and the traditional.Non-tuberculo-mycobacterium were unsusceptible to most antituberculous drugs, while macrolide and fluoroquinolones were found to be more susceptible world widely. Agar dilution method was performed to determine the MIC of 6 drugs. The results showed that macrolide and amikacin were apparently minor than their susceptibility breakpoints, but fluoroquinolones were close to the breakpoints. To improve the prognosis of chronic hand special infections, we choose macrolide and...
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