Stepwise implementation of a new diagnostic algorithm for multidrug-resistant tuberculosis in Haiti

SETTING

The uptake of tests endorsed by the World Health Organization to detect and appropriately confirm multidrug-resistant tuberculosis (MDR-TB) in low-income countries remains insufficient.

OBJECTIVE

To validate the implementation of line-probe assays (LPA) and liquid culture to develop an algorithm to detect MDR-TB in the challenging setting of Haiti.

METHODS

Through an EXPAND-TB (Expanding Access to New Diagnostics for TB) partnership, proficiency testing and validation of 221 acid-fast bacilli positive specimens were performed. Sensitivity, cost and processing time were analysed.

RESULTS

Using liquid vs. solid culture shortened the turnaround time from 54 to 19 days, with a sensitivity of 100% vs. 98.6% and a total cost reduction of 13%. LPA detected all TB and MDR-TB cases at a lower cost than culture, in a mean time of 7.5 days.

CONCLUSION

The combined use of molecular and liquid culture techniques accelerates the accurate diagnosis of TB and susceptibility testing against first-line drugs in a significantly shorter time, and is less expensive. The implementation of this new algorithm could significantly and accurately improve the screening and treatment follow-up of patients affected with TB and MDR-TB.

Erm(41)-dependent inducible resistance to azithromycin and clarithromycin in clinical isolates of Mycobacterium abscessus

OBJECTIVES

The ribosomal methylase Erm(41) confers inducible resistance to macrolides in Mycobacterium abscessus. The aim of this work was to systematically study and compare drug susceptibility to clarithromycin and azithromycin in M. abscessus and Mycobacterium chelonae clinical isolates with a particular focus on inducible drug resistance.

METHODS

Clinical isolates of M. abscessus subsp. abscessus (n = 21), M. abscessus subsp. bolletii (n = 16), M. abscessus subsp. massiliense (n = 10) and M. chelonae (n = 22) were characterized regarding their erm(41) and rrl genotypes and subjected to drug susceptibility testing (DST) for clarithromycin and azithromycin. Microdilution DST was performed in cation-adjusted Mueller-Hinton broth (pH 7.4) with readings at days 3, 7 and 12 and with pre-incubation at subinhibitory macrolide concentrations for erm(41) induction. In addition, the influence of variations in pH and growth medium on DST results was examined.

RESULTS

MICs of azithromycin were consistently higher than those of clarithromycin. In strains with an inducible erm(41) gene, high median MICs of ≥256 mg/L on day 12 were observed for both clarithromycin and azithromycin. Inducible resistance was at least as pronounced for azithromycin as for clarithromycin.

CONCLUSIONS

Our findings do not support the suggestion of a preferential use of azithromycin over clarithromycin in order to limit inducible macrolide resistance. Both compounds provoked a comparable resistance phenotype in M. abscessus. Caution is needed when using either azithromycin or clarithromycin for treatment of M. abscessus infections.

Molecular clues of a microepidemy among homeless tuberculosis patients in Budapest due to a new and local Mycobacterium tuberculosis clade

In Budapest, the capital of Hungary, one of the most important tuberculosis related risk factors is homelessness. The aim of this retrospective study was the genetic characterization of Mycobacterium tuberculosis strains isolated from 66 homeless tuberculosis patients by spoligotyping and mycobacterial interspersed repetitive unit (MIRU) typing. The study identified a local microepidemy in the district with the highest tuberculosis incidence of Budapest. Further genetic characterization has shown that the microepidemy was due to a locally emerged Budapest-specific lineage of M. tuberculosis. These data may serve as a reference to better monitor and understand the patterns and transmission dynamics of tuberculosis in this at-risk population and is the first report on genetic diversity of M. tuberculosis in today's Hungarians. The findings also indicate that tuberculosis control and prevention steps among the homeless need to be strengthened.

A population-based case-control study on the effect of bronchial asthma during pregnancy for congenital abnormalities of the offspring

Bronchial asthma is one of the most common maternal diseases complicating pregnancy. We assessed the risks of congenital abnormalities in a case-control population-based analysis using the dataset of the Hungarian Case-Control Surveillance of Congenital Abnormalities between 1980 and 1996. Of the 22,843 cases with congenital abnormalities, 511 (2.2%) had mothers with bronchial asthma, while of the 38,151 matched control subjects without congenital abnormalities 757 (2.0%) had mothers with bronchial asthma (unadjusted prevalence odds ratios [POR] 1.2; 95% CI: 1.0-1.3). In all mothers with bronchial asthma, a higher incidence of respiratory tract infections and higher drug intake could be observed. In the case group of medically recorded bronchial asthma, a slightly increased risk for club foot has been revealed. However, this weak association could be explained by the higher proportion of preterm births in this group. The main limitation of the analysis was that at the time of data collection only a small proportion of pregnant mothers were using anti-asthma medications recommended by the actual guidelines.

No teratogenic effect of prenoxdiazine: a population-based case-control study

The objective of this study was to investigate the human teratogenic potential of oral prenoxdiazine treatment during pregnancy. The analysis of cases with congenital abnormalities and their matched controls without congenital abnormalities was performed in the large population-based data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996. Of the 22,843 pregnant women who had offspring with congenital abnormalities, 158 (0.7%) were treated with prenoxdiazine. Of the 38,151 pregnant women who had babies without any defects in the study period (control group), 226 (0.6%) were treated with prenoxdiazine (adjusted prevalence odds ratio, 1.0; 95% confidence interval, 0.8-1.3). The comparison of cases and their matched controls did not show a significantly higher rate of prenoxdiazine treatment during the second and third months of gestation in the total (adjusted prevalence odds ratio, 1.4; 95% confidence interval, 0.9-2.2) or in any group of congenital abnormalities. Treatment with prenoxdiazine during pregnancy did not have any teratogenic risk to the fetus. Thus, prenoxdiazine treatment in pregnant women with an unproductive cough may be beneficial.

Molecular epidemiology of drug-resistant tuberculosis in Hungary

Sixty-eight drug-resistant Mycobacterium tuberculosis isolates (44.2% of all resistant cases) were analyzed by IS6110 restriction fragment length polymorphism fingerprinting and spoligotyping to provide a deeper insight into the status of drug-resistant tuberculosis in Hungary. A total of 54.4% of the drug-resistant cases and 75% of the multidrug-resistant cases could be clustered. Analysis of the spoligotyping patterns of the strains revealed a high rate (66.2%) of infection by the Haarlem genotype, while none of the patients were infected by the Beijing genotype. The magnitude and the dynamics of drug-resistant tuberculosis are underestimated in Hungary.

[Tuberculosis due to multidrug resistant Mycobacterium tuberculosis Beijing genotype identified by DNA fingerprinting: the first case identified in Hungary]

In a 28 years old Mongolian woman in whom pulmonary tuberculosis was diagnosed a poly- and multidrug (isoniazid, rifampicin, pyrazinamide, ethambutol, streptomycin) resistant Mycobacterium tuberculosis was isolated from sputum in 2002. Since the patient was from a country with high tuberculosis incidence it was conceivable that she had been infected by a strain with primary resistance in Mongolia. In order to confirm the origin of the strain an IS6110-based DNA fingerprint test was performed on the isolate. The assay revealed that the isolated M. tuberculosis strain belonged to the so-called Beijing family which was never detected in Hungary before.

Conventional and molecular epidemiology of tuberculosis in homeless patients in Budapest, Hungary

In Hungary the incidence of tuberculosis among the homeless population was 676 per 100,000 in 2002. Sixty-nine percent (140 patients) of all homeless tuberculosis patients were notified in Budapest (the capital). Therefore, a retrospective study that included 66 homeless tuberculosis patients notified in Budapest in 2002 was conducted to determine the rate of recent transmission of the disease and medical risk factors and to identify transmission pathways by means of conventional and molecular epidemiologic methods. IS6110 DNA fingerprinting revealed that 71.2% of the isolates could be clustered. Thirty-four (51.5%) patients belonged to five major clusters (size, from 4 to 11 individuals), and 13 (19.7%) belonged to six smaller clusters. Additional analysis of patient records found that 2 (18%) of the 11 patients in cluster A, 3 (37.5%) of the 8 patients in cluster B, and 2 (33%) of the 6 patients in cluster C were residents of the same three homeless shelters during the diagnosis of tuberculosis. Review of the database of the National Tuberculosis Surveillance Center (NTSC) revealed that 21.2% of the cases have not been reported to the NTSC. These findings indicate that the screening and treatment of tuberculosis among the homeless need to be strengthened and also warrant the review of environmental control steps in public shelters. Improvement of adherence of clinicians to surveillance reporting regulations is also necessary.

Laboratory diagnostic aspects of drug resistant tuberculosis

Multi-drug resistant strains of Mycobacterium tuberculosis (MDR-TB) are present world wide, and in many areas constitute a serious threat to the efficacy of TB control programs. The most effective strategies to limit further spread of MDR-TB are rapid detection of drug resistance followed by prompt and effective therapy. Routine laboratory diagnosis of drug resistance in TB requires a viable, pure culture of M. tuberculosis. Use of liquid media has decreased the turn around time for susceptibility test results however, because of the slow growth of M. tuberculosis these assays can still take 10 to 14 days. Alternatively, an increased understanding of the molecular basis for resistance to the antituberculosis drugs can greatly contribute to further decreasing turn around time. Based on this information, more precise and rapid molecular testing can be developed and lead to more appropriate and timely treatment regimens. In this review, we discuss methods for, and problems encountered in, performing TB drug susceptibility assays. Descriptions of routine protocols will be followed by recent developments in molecular detection of drug resistance.

[Chronic necrotizing pulmonary aspergillosis in an immunocompromised patient]

A case with chronic necrotizing pulmonary aspergillosis that was mimicking the radiomorphology of malignant tumor was reported. The patient was admitted to hospital with progression of a left upper lobe infiltrate which was known and under regular observation for 8 years, and haemoptoe. Computer tomography scan showed a spiculated abnormality in the left upper lobe with mediastinal lymphadenomegaly. Based on this finding pulmonary malignancy was suspected and, therefore, the patient was referred to surgical intervention. The post surgical histology revealed aspergillus in the specimen. Since signs of vascular invasion could not be detected microscopically and the disease developed in immunocompromised patient (due to diabetes mellitus and long term steroid treatment) the clinical condition was determined as chronic necrotizing aspergillosis. It is very likely that the pathogen infected the patient during his daily work in a bakery. The present paper also summarizes the clinical aspects, differential diagnosis and therapy of different forms of pulmonary aspergillosis with emphasis on chronic necrotizing pulmonary aspergillosis.

Pulmonary tuberculosis due to Mycobacterium bovis subsp. caprae in captive Siberian tiger

We report the first case of pulmonary tuberculosis caused by Mycobacterium bovis subsp. caprae in a captive Siberian tiger, an endangered feline. The pathogen was isolated from a tracheal aspirate obtained by bronchoscopy. This procedure provided a reliable in vivo diagnostic method in conjunction with conventional and molecular tests for the detection of mycobacteria.

[Treatment of bronchial asthma in pregnancy]

The prevalence of bronchial asthma, similarly to the normal population, is also increasing among pregnant women. Asthma a chronic inflammatory disease of the airways, is one of the most common medical problems that can complicate pregnancy. The cornerstone of asthma management in pregnancy is to implement such treatment strategies that can maintain normal maternal pulmonary function and prevent fetal complications. The aim of the present article is to summarize the recent publications and guidelines on the safety and efficacy issues of asthma treatment during pregnancy.

A Possible Association between Oral???Aminophylline Treatment during???Pregnancy and Skeletal Congenital Abnormalities

OBJECTIVE

To study the human teratogenic potential of oral aminophylline treatment during pregnancy.

DESIGN AND SETTING

The analysis of each case and its matched controls, as well as comparison of population or patient controls and cases with 25 groups of congenital abnormalities in the population-based data set of the large Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-1996.

STUDY PARTICIPANTS

38 151 pregnant women who had newborn infants without any congenital abnormalities (population control group), 22 843 pregnant women who had newborn infants or fetuses with congenital abnormalities, and 834 patient controls with Down's syndrome.

MAIN OUTCOME MEASURES

Prevalence of aminophylline use in cases with the 25 congenital abnormality groups compared with population control and patient control groups.

RESULTS

The prevalence of oral aminophylline treatment during pregnancy was similar in the case group (1374 pregnant women; 6.0%) and the population control group (2284 pregnant women; 6.0%) [crude prevalence odds ratio (POR) 1.0, 95% confidence interval (CI) 0.9-1.1], while it was higher in the patient control group (55 pregnant women; 6.6%). Comparisons of total population or patient control groups and cases with the 25 different congenital abnormality groups, as well as analysis of cases and their matched controls, indicated an association between aminophylline use and congenital abnormalities of the musculoskeletal system (crude POR 5.0, 95% CI 1.4-18.4, adjusted POR 4.7, 95% CI 1.3-17.2 for aminophylline treatment during the second through third months of gestation; crude POR 1.5, 95% CI 1.0-2.2, adjusted POR 1.5, 95% CI 0.9-2.2 for aminophylline treatment during the entire pregnancy), particularly pectus excavatum/carinatum (3.5 times excess). There was a possible association between aminophylline and clubfoot and posterior cleft palate. These findings may be connected with recall bias, although this bias was restricted by the evaluation of maternal drug use only during the critical period of the above congenital abnormalities and by evaluating medically recorded aminophylline treatment, as well as by the use of patient controls.

CONCLUSION

Our findings and previous animal investigations can only be regarded as a signal for the possible association between oral treatment with aminophylline during pregnancy and some congenital abnormalities of the skeletal system.

Analysis of tuberculosis surveillance in Hungary in 2000

SETTING

Hungary, Central Europe, with a population of 10.3 million living in 20 administrative districts (19 counties and the capital).

OBJECTIVE

To summarize the results of the first year of the revised National Tuberculosis Surveillance System.

DESIGN

Retrospective survey of the National Tuberculosis Surveillance Center (NTSC) database.

METHODS

Analysis of data on all tuberculosis cases reported to the NTSC in 2000. Drug susceptibility results were evaluated in line with WHO and IUATLD definitions.

RESULTS

During 2000, a total of 3598 patients with tuberculosis were reported. Only 40% of these were bacteriologically confirmed. Although susceptibility testing has been required for previously untreated culture-positive cases, only 801 (67.8% of the bacteriologically confirmed cases) were tested in 2000. Drug resistance was detected in 10.7% of previously untreated and in 23.5% of previously treated patients. Multidrug-resistant (MDR) cases were not common: only 1.5% of the isolates from previously untreated patients and 4.9% of those from previously treated patients were MDR.

CONCLUSIONS

The results suggest that the NTSC should work towards increasing the numbers of cases that are bacteriologically confirmed. In addition, some form of surveillance system should be instituted to ensure that mandatory susceptibility testing is performed on all isolates from previously untreated tuberculosis patients.

Rapid and simple approach for identification of Mycobacterium tuberculosis complex isolates by PCR-based genomic deletion analysis

Although the virulences and host ranges differ among members of the Mycobacterium tuberculosis complex (TBC; M. tuberculosis, M. africanum, M. canettii, M. microti, M. bovis, and M. bovis BCG), commercially available molecular assays cannot differentiate these organisms because of the genetic identities of their 16S rRNA gene sequences. Comparative genomic analyses with the complete DNA sequence of M. tuberculosis H37Rv has provided information on regions of difference (RD 1 to RD 16) deleted in members of the TBC other than M. tuberculosis. To determine whether deletion analysis could accurately differentiate members of TBC, we used PCR to assess the presence or absence of specific regions of the genome in 88 well-characterized isolates of M. tuberculosis, M. africanum, M. microti, M. bovis, and M. bovis BCG. The identifications obtained by use of the specific deletion profiles correlated 100% with the original identifications for all TBC members except M. africanum, but further characterization resulted in profiles specific for all members. Although six RD regions were used in the analyses with the original 88 isolates, it was found that the use of RD 1, RD 9, and RD 10 was sufficient for initial screenings, followed by the use of RD 3, RD 5, and RD 11 if the results for any of the first three regions were negative. When 605 sequential clinical isolates were screened, 578 (96%) were identified as M. tuberculosis, 6 (1%) were identified as M. africanum, 8 (1%) were identified as M. bovis, and 13 (2%) were identified as M. bovis BCG. Since PCR-based assays can be implemented in most clinical mycobacteriology laboratories, this approach provides a rapid and simple means for the differentiation of members of TBC, especially M. bovis and M. tuberculosis, when it is important to distinguish between zoonotic sources (i.e., cattle and unpasteurized dairy products) and human sources of tuberculosis disease.

Molecular characterization of rifampin-resistant isolates of Mycobacterium tuberculosis from Hungary by DNA sequencing and the line probe assay

Two regions of rpoB associated with rifampin resistance were sequenced in 29 rifampin-resistant (determined by the proportion method) isolates of Mycobacterium tuberculosis obtained from patients from three counties in Hungary. Of the 29 resistant strains, 27 had a mutation in either the 81-bp region (26 strains) or the N-terminal region (1 strain), while the other 2 strains had no mutations in either region. The locations and frequencies of the mutations differed from those previously reported. The most common mutation in this study, D516V, was found in 38% of the Hungarian strains, a frequency 2 to 10 times higher than that found in studies from other countries. These same 29 isolates were also evaluated with the Inno-LiPA Rif. TB test (LiPA), a reverse hybridization assay for the rapid detection of rifampin resistance. Although LiPA detected the presence of an rpoB mutation in 26 of the resistant isolates, the type of mutation could not be determined in 4 isolates because the mutations present were not among those included on the LiPA strip. In addition, a silent mutation in one of the rifampin-susceptible control strains was interpreted as rifampin resistant by LiPA. These findings demonstrate the importance of validating this rapid molecular test by comparison with DNA sequence results in each geographic location before incorporating the test into routine diagnostic work.

[Routine direct detection of Mycobacterium tuberculosis with a rapid test of polymerase chain reaction applied to a Hungarian patient population]

The results of the present study, based on 1869 examined clinical specimens of 543 patients, represent the Hungarian parameters of a PCR test. By using the final and resolved results, the clinical sensitivity, specificity, positive and negative predictive values were 83.8%, 99.2%, 95.4% and 97%, respectively for PCR, 63.5%, 100%, 100% and 93.5%, respectively for culture, and 16.2%, 100%, 100% and 86.3%, respectively for Ziehl-Neelsen (ZN) staining. These results are essential to allow Hungarian clinicians to interpret PCR results in accordance with local conditions. The present study has demonstrated a high sensitivity (PCR vs. culture and smear, p < 0.01) and an excellent specificity of PCR. Our results indicate that the majority of M. tuberculosis-positive specimens can be identified rapidly with the test and, because of the high negative predictive value, the PCR test can help to exclude tuberculosis from the differential diagnosis in 24 hours. Moreover, the PCR can detect the presence of M. tuberculosis in 66.6% of ZN-negative and subsequently culture-positive specimens at the time of admission. The results of PCR must be interpreted with extreme caution, and the procedure is recommended only for laboratories, which simultaneously perform culture and microscopy for control of the performance of PCR tests.

False-positive results for Mycobacterium celatum with the AccuProbe Mycobacterium tuberculosis complex assay

Mycobacterium celatum type 1 was found to cross-react in the AccuProbe Mycobacterium tuberculosis complex assay. Subsequently, we found a statistically significant increase in the relative light units with lower temperatures, suggesting that it is necessary to perform this AccuProbe assay at between 60 and 61 degrees C. We also recommend the inclusion of M. celatum type 1 as a negative control.

Comparison of recoveries of mycobacterium tuberculosis using the automated BACTEC MGIT 960 system, the BACTEC 460 TB system, and Löwenstein-Jensen medium

Using two different liquid media and one conventional solid medium, a total of 57 mycobacterial isolates (Mycobacterium tuberculosis, n = 55; nontuberculous mycobacteria, n = 2) were recovered from 377 clinical specimens. The rates of recovery of M. tuberculosis were 96. 4% with the BACTEC MGIT 960 liquid medium, 92.7% with BACTEC 12B liquid medium, and 81.8% with the Löwenstein-Jensen (LJ) medium. The mean time to detection of M. tuberculosis in smear-positive specimens was 12.6 days for BACTEC MGIT 960 medium, 13.8 days for BACTEC 12B medium, and 20.1 days for LJ medium, and in smear-negative specimens it was 15.8 days for BACTEC MGIT 960 medium, 17.7 days for BACTEC 12B medium, and 42.2 days for LJ medium. The rates of contamination were 3.7, 2.9, and 1.2% for the BACTEC MGIT 960, BACTEC 12B, and LJ media, respectively. In conclusion, the nonradiometric, fully automated 7-ml BACTEC MGIT 960 system can be considered a viable alternative to the semiautomated, radiometric BACTEC 460 TB system.

Accessory function and costimulatory molecule expression of alveolar macrophages in patients with pulmonary tuberculosis

An effective immune response against M. tuberculosis requires a coordinated interaction of alveolar macrophages (AM) and lymphocytes. Secondary signals, such as accessory function (AF) of antigen presenting cells and interaction of costimulatory molecules are also important for T cell activation. In the present study we determined the AF and the expression of CD11a, CD54, CD58, CD80, CD86 and HLA-DR costimulatory molecules by AMs lavaged from patients with pulmonary tuberculosis and controls. We hypothesized that alterations in AF and costimulatory molecule expression may influence the presentation of tuberculosis. Therefore these parameters were also correlated with the radiographic extension of the disease. AMs of patients with tuberculosis exhibited an increased AF and a significantly increased expression of co-stimulatory molecules compared with controls. Furthermore, we observed that the expression of CD54 (ICAM-1) decreased with the course of the disease. We conclude that the infection by M. tuberculosis results in an increased AF of AMs and the activity of AMs remains uninfluenced by the extension of the disease. Clear-cut changes of patterns of costimulatory molecule expression by AMs could not be observed with the progression of tuberculosis.

Polymorphisms at position -308 in the promoter region of the TNF-alpha and in the first intron of the TNF-beta genes and spontaneous and lipopolysaccharide-induced TNF-alpha release in sarcoidosis

TNF-alpha is a potent pro-inflammatory cytokine. Previous studies have proved that biallelic polymorphisms in the TNF-alpha (-308, TNFA) and TNF-beta genes (intron 1, TNFB) influence TNF-alpha production. In sarcoidosis, a chronic granulomatous disease, as a result of an unknown in vivo activation bronchoalveolar lavage (BAL) cells release high amounts of TNF-alpha, spontaneously and after in vitro stimulation. Thus, sarcoidosis could serve as a model to test the in vivo effect of TNF gene polymorphisms. We determined the TNFA and TNFB polymorphisms of 44 patients with sarcoidosis and found the following allele frequencies: 0.80, 0.20, 0.38 and 0.62 for TNFA1, TNFA2, TNFB1 and TNFB2, respectively. To examine the in vivo effect of the named polymorphisms on the TNF-alpha production, the spontaneous and LPS-induced TNF-alpha release of BAL cells and peripheral blood mononuclear cells were also determined in patients with sarcoidosis. Statistical analysis did not reveal any significant difference between sarcoidosis patients with different genotypes. The results show that TNFA and TNFB polymorphisms do not determine the level of TNF-alpha release of mononuclear cells activated during the course of sarcoid inflammation.

Different cytokine patterns correlate with the extension of disease in pulmonary tuberculosis

The relative amounts of different pro- and anti-inflammatory cytokines released at the site of infection by bronchoalveolar lavage (BAL) cells may influence the presentation of tuberculosis. To investigate this hypothesis the in situ release by BAL cells of the following cytokines was measured and correlated with the chest X-ray findings of 43 patients with pulmonary tuberculosis: interleukin (IL)-8, macrophage inflammatory protein-1alpha (MIP-1alpha), IL-6, tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), interferon-gamma (IFN-gamma), IL-2, IL-4 and IL-5. The release of IL-8 and IL-6 decreased with the progression of the disease, while the release of MIP-1alpha was increased in patients with advanced tuberculosis. The release of TNF-alpha and TGF-beta did not differ between patients with or without cavitary lesions. The Th1 (IFN-gamma and IL-2) and Th2 (IL-4 and IL-5) cytokine release exhibited a gradual increment with the advance of tuberculosis. Thus, our data provide evidence that a Th0 cytokine pattern is predominant at the site of pulmonary tuberculosis. In conclusion, immunoparalysis status could not be observed in our patients with severe tuberculosis.

Comparison of the mycobacteria growth indicator tube with MB redox, Löwenstein-Jensen, and Middlebrook 7H11 media for recovery of mycobacteria in clinical specimens

The rate of recovery and the mean time to detection of mycobacteria in clinical specimens were evaluated with two nonradiometric broth-based systems, the Mycobacteria Growth Indicator Tube (MGIT) and MB Redox systems. The data obtained for each system were compared with each other and with those obtained with the Löwenstein-Jensen (LJ) and Middlebrook 7H11 reference media. A total of 117 mycobacterial isolates (Mycobacterium tuberculosis, n = 112; nontuberculous mycobacteria, n = 5) were detected in 486 clinical specimens. The recovery rates for M. tuberculosis were 91 of 112 (81.3%) isolates with MGIT and 81 of 112 (72.3%) isolates with MB Redox. The combination of MGIT plus MB Redox recovered 104 of the 112 (92.9%) M. tuberculosis isolates. MGIT plus LJ plus Middlebrook 7H11 recovered 106 of the 112 (94.6%) isolates, MB Redox plus LJ plus Middlebrook 7H11 recovered 99 of the 112 (88.4%) isolates, and LJ plus Middlebrook 7H11 recovered 84 of the 112 (75. 0%) isolates. The mean time to detection of M. tuberculosis in smear-positive specimens was 7.2 days with MGIT, 6.9 days with MB Redox, 20.4 days with LJ, and 17.6 days with Middlebrook 7H11. The mean time to detection of M. tuberculosis in smear-negative specimens was 19.1 days with MGIT, 15.5 days with MB Redox, 25.8 days with LJ, and 21.6 days with Middlebrook 7H11. The contamination rates were 4.4, 3.8, 2.1, and 2.7% for MGIT, MB Redox, LJ, and Middlebrook 7H11, respectively. In conclusion, MGIT and MB Redox can be viable tools in the routine mycobacteriology laboratory.

Application of a computer-directed automated microscope in mycobacteriology

Microscopy is currently the fastest, cheapest and most easily performed technique in mycobacteriology; it can be used in any laboratory. However, the sensitivity of microscopy is unsatisfactory and it is time-consuming. To eliminate these drawbacks, we have constructed a computer-directed automated microscope. To evaluate the equipment, we examined a total of 132 smears of sputum and 74 smears of liquid media. Manual microscopy was positive for 53 and negative for 79 sputum smears, while automated microscopy was positive for 55 and negative for 77 sputum smears. Both methods furnished 50 positive and 24 negative smears of liquid media. We conclude that the automated microscope is able to detect acid-fast bacteria, the examination procedure with the instrument is more rapid (1.8-3.5 min/slide) and it is always possible to follow the standard recommendations of microscopy.

[Pulmonary echinococcosis]

Two patients with pulmonal Echinococcosis are presented by the authors. Contact with cestoda carrier animals cannot be revealed. At the first patient, who was without any complaints, the two round shadows in her chest X-ray were detected accidentally by screening examination and before the operation only eosinophilia, many eosinophil granulocytes in the pleural effusion and the positive complement binding reaction were related to the Echinococcosis, which was proved by the histological examination of the intraoperative biopsy. The other patient had complaints during months. In this case the Echinococcus granulosus broke into the bronchus and emptied in the sputum. Postoperative histological diagnosis can be obtained by help of the excision from the intraluminal alteration which was visible during bronchoscopy. The authors summarize the etiology, the clinical signs, the diagnose and the therapy of Echinococcosis. They call attention to the incidence of this mainly tropical disease in Hungary and to the rare soliter pulmonal manifestation of the Echinococcosis.