To determine the usefulness of a diagnostic kit for mycobacterial infection, we performed a five-hospital cooperative clinical study using serodiagnosis kits (Myco Dot Tm Test) to detect antibody for lipoarabinomannan (LAM) which is a membrane-derived component of mycobacterial species. We tested LAM antibody in the sera of patients with mycobacterial infection as well as healthy persons. Procedures for using the serodiagnosis kit are actually simple.
Out of 130 cases of active pulmonary tuberculosis, 103 cases (79%) were positive for anti-LAM, and cases out of 24 cases of active atypical mycobacterial infection, 15 (63%) were positive. On the contrary, only 4% of healthy volunteers (1 out of 25 persons) were positive on this test.
In conclusion, this diagnostic kit might be a useful test for early and supportive diagnosis of mycobacterial infections based on its sensitivity and specificity.

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Diabetics are prone to bacterial infection in part, due to polymorphonuclear neutrophil dysfunction, but the precise mechanism is not yet fully explained. Of many complications, diabetes mellitus (DM) is one of the most common diseases, which causes pulmonary tuberculosis.
To elucidate the mechanism of susceptibility to tuberculosis infection in patients with diabetes mellitus, we measured IFN-γ, IL-12 and IL-10 productions by CD 4⁺ α β AT cells and autologous monocytes stimulated with live BCG in patients with pulmonary tuberculosis complicated with DM (TB+DM) or without DM (TB) and healthy controls. The levels of IFN-γ and IL-12 production in TB patients were significantly lower than those in the control. These cytokine productions were also lower in TB+DM patients than in TB patients significantly. The level of IL-10 production in TB patients were highest among these three groups. The production of this cytokine in TB+DM patients was lowest. The level of IFN-γ production was singificantly lower in TB+DM patients under poor DM control than in those patients under good DM control and showed a significant negative correlation to HbA lc, an indicator of diabetic control. The period for negative conversion of culture finding in TB+DM patients under poor control was prolonged when compared with those in TB patients.
These results demonstrated the difference in cytokines secretion profile between TB patients and TB+DM patients, and suggest that the immunological mechanism underlying pathogenesis of tuberculosis might work differently between these two patients groups.

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We experienced small outbreaks of M. tuberculosis infection in two bars. 9 patients were diagnosed as tuberculosis by identifying M. tuberculosis from their sputa. Six of them were regular customers or employees of the bar, one of them was a family of employer of the bar who often visited there and the others were their family members. Each outbreak within the two bars was suspected of the common source of infection, because one patient was a regular customer of the both bars. The analysis of restriction fragment length polymorphism (RFLP) was done on 5 strains of M. tuberculosis which were isolated from five of 9 patients. The result unexpectedly showed that 5 isolates were classified into 3 groups. Within each group, identical fingerprints were shown. It does mean that each outbreak in two bars was originated from independent source. There was also one relapsed case of tuberculosis. He was suspected of relapsed tuberculosis after a period of 7 years because of the similarity of drug resistance compared with his primary tuberculosis. It was cleared up that 3 different strains of M. tuberculosis were concerned with these outbreaks in the two bars. In this case, almost all patients were heavy drinkers, however, liver dysfunction and malnutrition were not recognized among them. These experiences indicate that a place like bar may be a space of infection of M. tuberculosis. We should always keep in mind a spread of tuberculosis in a place like a bar as one of problems in tuberculosis control.

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The BCG vaccines will celebrate the 100th anniversary of their discovery in a decade at the beginning of the next century since Albert Calmette and Camille Guebrin had presented it before the Academie des Sciences in 1908. At present tuberculosis kills more people than any other infectious disease about 3 million people a year, including almost 300, 000 children under 15, and is producing over 7, 000 deaths and over 24, 000 new cases every day. Therefore, WHO declared a global ealth emergency in 1993. More worse, recently multi-drug resistant tubercle bacilli are emerging rapidly making TB patients incurable.
Under these situations we need a potent anti-tuberculosis vaccine. So first of all, we must check the century-old BCG before proceeding further.
At moment, the BCG vaccines are being used worldwide in the largest quantities in the world, but still most controvercial vaccines anywhere.
I would like to describe here their success and failure in the combat against the white plague.
1. The Expanded Programme on Immunization (EPI).
In 1974, when the EPI was launched by WHO, less than 5% of the world children were immunized against six infectious deseases including tuberculosis. In 1995 statistics, BCG gave the highest vaccination coverage, 87% higher than any other 5 vaccines of EPI for children. The BCG in EPI must have saved a lot of infants as the vaccine, has been proved to be most effective against the blood-born tuberculosis of child type.
2. The efficacy of BCG vaccination against tuberculosis.Results of each 10 of randomized controlled trials (RCT) and Case-control studies (CCS) showed the protective efficacy against tuberculosis as uncertain, unpredictable, as protective efficacy varied from 80% to 0%.
More recently, a Meta-analysis of selected papers on BCG field trials which were so far collected. They recalculated vaccine protective effect separately for pulmonary TB and for meningeal/miliary TB in the trials.
As the result, it was found that protective effect against pulmonary TB could not be calculated, but protective effect against meningeal and miliary TB was calculated as 86%, 75% respectively, in RCT and CCS, being higher than against pulmonary TB.
3. The duration of BCG efficacy against tuberculosis was confirmed to continue for 15 years after vaccination. The incidence of every form of tuberculosis decreased steeply during the 15 years following vaccination.
4. BCG revaccination.
A WHO statement was issued in 1995 mentioning that there is no definitive evidence that repeated BCG vaccination confers additional protection against tuberculosis.
Therefore WHO has not recommended to repeat BCG vaccination because of no scientific evidence to support this practice. Multiple BCG revaccinations are not indicated in any persons.
5. Complications with BCG
Second IUATLD study (1988) on complications induced by BCG was reviewed, especially following two points:
1-2) Regional suppurative lymphadenitis
3) Generalized lesions: fatal cases 1-2 Several Afirican regions had experienced that the risk of outbreak of suppurative BCG lymphadenitis was low for vaccines with Glaxo and Japanese strains, but much higher for vaccines with Pasteur. This experience in nineteen eighties has led EPI to replace the Pasteur BCG vaccine with less reactogenic BCG, Japanese or Glaxo BCG to solve the outbreak of suppurative adenitis complication.
3 At moment, the only contra-indication of EPI BCG vaccination is symptomatic HIV infection (AIDS), but in the future asymptomatic HIV infection should be placed on alert, because fatal BCG generalized disseminations have already been experienced by HIV positive vaccinees although in a few cases in USA.

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