Molecular Identification of Extrapulmonary Vaccine Adverse Events after BCG in Paraffin-Embedded Specimens

According to the World Health Organization (WHO), around 1 million children worldwide are diagnosed with tuberculosis each year. The Bacillus Calmette-Guérin (BCG) vaccine has been used around the world for over 100 years. The complications of the BCG vaccination can occur in about 0,06% of children and include local or systemic adverse reactions. Due to the close analogy between the vaccine strain and other species of the Mycobacterium tuberculosis complex (MTBC), molecular methods are recommended for differential diagnosis of Vaccine adverse events (VAE) after BCG. The ability to quickly and specifically identify BCG is important in view of different treatment regimens. The aim of the study was to assess the usefulness of genetic testing for Mycobacterium bovis BCG in the paraffin-embedded specimens' methods. We describe two cases of VAE in immune-compromised children presenting with osteoarticular changes that had been clinically suspected of tuberculosis and led to molecular identification through GeneXpert, GenoType MTBC, and Spoligotyping. Results: Mycobacterium bovis BCG was detected in osteoarticular changes embedded in paraffin block of two patients. Conclusion: Genetic tests using paraffin-embedded materials allow for quick identification and differential diagnosis of patients with Tuberculosis and VAE after BCG. This is an important issue, especially in cases where the tissue has only been submitted for histopathological examination without microbiological diagnostics for tuberculosis.

Detection of Mycobacterium tuberculosis Complex Genetic Material in a Free-Living Brown Bear (Ursus arctos)

Mycobacterium tuberculosis complex (MTBC) has rarely been detected in bears (Ursidae). We describe detection of MTBC genetic material using a single-tube, high-multiplex PCR and fluorescence-based detection system in a throat swab collected from a free-living, problem individual during immobilization and telemetry collar deployment. Mycobacterial culture was negative in all samples.

Pregnancy in European bison (Bison bonaus) with generalized tuberculosis - no evidence of vertical transmission

INTRODUCTION AND OBJECTIVE

One of the main health threats to the endangered European bison (Bison bonsasus) is bovine tuberculosis, the pathogenesis of which in this species is not fully known. The aim of the study was to confirm a possible case of vertical transmission from a pregnant European bison with generalized tuberculosis to its 12-week-old foetus.

MATERIAL AND METHODS

During the autopsy it was found that the bison had become pregnant, despite an advanced stage of tuberculosis. Material collected from the organs and foetus was placed on Lowenstein and Stonebrink media and incubated at 37 °C for 12 weeks.

RESULTS

Mycobacteria were isolated from the lungs and lymph nodes; however, the tissue of the foetus and fragments of the reproductive system were negative.

CONCLUSIONS

Vertical transmission was excluded, although it cannot be ruled out that infection could occur as pregnancy progresses.

Microbiological and molecular monitoring for bovine tuberculosis in the Polish population of European bison (Bison bonasus)

INTRODUCTION AND OBJECTIVE

In recent years, bovine tuberculosis (BTB) has become one of the major health hazards facing the European bison (EB, Bison bonasus), a vulnerable species that requires active protection, including regular and effective health monitoring. Monitoring of zoonotic disease in wildlife is also an important part of public health protection. The aim of the study was to determine whether BTB still influences the EB population in Poland.

MATERIAL AND METHODS

During 2017-2019, mandibular, retropharyngeal and mediastinal lymph nodes were collected from 90 EB during post-mortem examination, and then cultivated on Lowenstein-Jensen and Stonebrink media. Isolated strains were subjected to molecular analysis to determine the species, spoligotype and MIRU-VNTR pattern.

RESULTS

Lesions were found in lymph nodes originating from eight EB (8.89%). Positive microbiological cultures for mycobacteria were obtained in samples from six (6.67%) EB. The isolated strains were identified as Mycobacterium caprae (material from four EB) and atypical mycobacteria (material from two EB). For M. caprae strains spoligotype M. bovis 4_CA 1600 was identified and the MIRU-VNTR pattern was identified as 345751355413232.

CONCLUSIONS

It is recommended that this potentially dangerous disease should be monitored in EB via a comprehensive strategy based on a combination of microbiological and molecular methods. Such monitoring will protect the health of both animals and humans.

Antibody responses in European bison (Bison bonasus) naturally infected with Mycobacterium caprae

Mycobacterium caprae, a member of the Mycobacterium tuberculosis complex, infects humans and animals causing lesions and disease like that of Mycobacterium bovis. The aim of this study was to evaluate antibody responses in European Bison (EB, Bison bonasus; a vulnerable species) naturally infected with M. caprae using dual path platform (DPP) BovidTB test and multi-antigen print immunoassay (MAPIA). Study cohorts consisted of naturally M. caprae-infected EB (n = 4), M. caprae-exposed but uninfected (n = 3), EB infected with non-tuberculous mycobacteria or other respiratory pathogens (n = 3), and negative controls (n = 19). M. caprae-infected EB were seropositive by both DPP and MAPIA; 3/4 were seropositive by DPP; and 4/4 were seropositive by MAPIA. One M. caprae-infected animal that developed generalized disease with most advanced gross lesions in the group produced the most robust antibody response. All 25 EB with no culture-confirmed M. caprae infection, including three animals exposed to M. caprae and three other animals infected with non-tuberculous pathogens, were seronegative on both tests. Antibody responses to M. caprae infection included IgM antibodies against MPB70/MPB83 and IgG antibodies to both MPB70/MPB83 and CFP10/ESAT-6. This study demonstrates the potential for use of serological assays in the ante-mortem diagnosis of M. caprae infection in EB.

Epidemiological characterization of Mycobacterium caprae strains isolated from wildlife in the Bieszczady Mountains, on the border of Southeast Poland

Background

The majority of animal tuberculosis (TB) cases reported in wildlife in Poland over the past 20 years have concerned the European bison inhabiting the Bieszczady Mountains in Southeast Poland: an area running along the border of Southeast Poland. As no TB cases have been reported in domestic animals in this region since 2005, any occurrence of TB in the free-living animals inhabiting this area might pose a real threat to local livestock and result in the loss of disease-free status. The aim of the study was to describe the occurrence of tuberculosis in the wildlife of the Bieszczady Mountains and determine the microbiological and molecular characteristics of any cultured strains. Lymph node samples were collected for analysis from 274 free-living animals, including European bison, red foxes, badgers, red deer, wild boar and roe deer between 2011 and 2017. Löwenstein–Jensen and Stonebrink media were used for culture. Molecular identification of strains was performed based on hsp65 sequence analysis, the GenoType®MTBC (Hain Lifescience, Germany) test, spoligotyping and MIRU-VNTR analysis.

Results

Mycobacterium caprae was isolated from the lymph nodes of 21 out of 55 wild boar (38.2%; CI 95%: 26.5%, 51.4%) and one roe deer. Since 2014, no new TB cases have been reported in the Bieszczady European bison population.

Conclusions

The identification of TB in wild boar in the Bieszczady is an alarming phenomenon, which requires further investigation. The Bieszczady mountains are a precious, unique area, home to many protected species. However, it is also the only area in Poland where TB cases have been reported in free-living animals. The occurrence of TB in wild boar inhabiting this area might pose a real threat to local livestock and many of the protected species (for example European bison that can share feeding places with wild boar). Given this situation, ongoing monitoring of the prevalence of TB should be conducted, and protective measures should be considered.

Czynniki predysponujące do rozwoju mykobakteriozy płuc u chorych z obecnością prątków niegruźliczych w materiałach z dróg oddechowych

Wstęp: W ostatnich latach w większości krajów Europy i w Stanach Zjednoczonych jest notowany wzrost częstości zakażeń układu oddechowego prątkami niegruźliczymi. Nie ma jednak zgodności opinii na temat wpływu różnych czynników na rozwój mykobakteriozy płuc w tej grupie chorych. Celem niniejszej pracy retrospektywnej było poszukiwanie czynników ryzyka mykobakteriozy płuc, w grupie chorych, u których wyhodowano prątki niegruźlicze z dróg oddechowych. Materiał i metody: Badaną grupę stanowiło 73 chorych, 23 mężczyzn i 50 kobiet, mediana wieku wyniosła 62.2 roku, z dodatnimi wynikami posiewów plwociny/wydzieliny oskrzelowej w kierunku prątków niegruźliczych, uzyskanymi w latach 2010–2015. Wyniki: Mykobakteriozę płuc (według American Thoracic Society/Infectious Diseases Society of America) rozpoznano u 36 chorych, kolonizację dróg oddechowych—w 37 przypadkach. Mykobakteriozę rozpoznawano istotnie częściej u chorych zakażonych M. kansasii, M. abscessus i M. avium/M. intracellulare w porównaniu z chorymi zakażonymi M. xenopi, M. gordonae i M. fortuitum (p < 0.0001). Wśród chorych na mykobakteriozę, w porównaniu z grupą z kolonizacją prątkami niegruźliczymi, było istotnie więcej kobiet niż mężczyzn (p < 0.007) oraz więcej chorych z wywiadem przebytej gruźlicy płuc lub mykobakteriozy (odpowiednio 28% i 8%, p = 0.038). Wykazano, że zakażenie M. kansasii, płeć żeńska oraz przebyta gruźlica lub mykobakterioza były istotnymi czynnikami predykcyjnymi aktualnego rozpoznania mykobakteriozy płuc. Wniosek: W badanej grupie chorych ryzyko zachorowania na mykobakteriozę było istotnie większe u kobiet, osób zakażonych M. kansasii oraz z przebytą gruźlicą lub mykobakteriozą płuc w przeszłości.

Factors predisposing to non-tuberculous mycobacterial lung disease in the patients with respiratory isolates of non-tuberculous mycobacteria

INTRODUCTION

An increasing incidence rate of respiratory isolates of non-tuberculous mycobacteria (NTM) has been noted recently in most European countries as well as in the US. Despite many publications, there is no consensus concerning the importance of different factors in promoting NTM lung disease (NTMLD). The aim of the present retrospective study was to analyse patients with positive NTM respiratory isolates in search of factors predisposing to NTMLD.

MATERIAL AND METHODS

73 patients, 23 males, 50 females, median age 62.2 years, in whom NTM have been cultured from respiratory specimen (sputum and/or bronchial washings), in the period 2010-2015, entered the study.

RESULTS

NTMLD (according to ATS/IDSA) has been recognised in 36 patients, airways colonisation by NTM - in 37 patients. NTMLD was diagnosed more often in the patients infected with M. kansasii, M. abscessus and M. avium/M. intracellulare comparing to those infected with M.xenopi, M. gordonae and M. fortuitum (p < 0.0001). The proportion of females to males was significantly higher in the NTMLD group comparing to the colonisation group (p < 0.007). Previous tuberculosis or mycobacteriosis were noted significantly more frequently in the group of patients with NTMLD comparing to the colonisation group (28% vs 8%, p = 0.038). Univariate regression analysis revealed M. kansasii, female gender, and previous tuberculosis or mycobacteriosis as significant predictors of NTMLD.

CONCLUSIONS

The risk factors of NTMLD recognition in the presented group of patients were the following: female gender, M. kansasii isolation, as well as past tuberculosis or mycobacteriosis.

PCR-based genomic deletion analysis of RD-regions in the identification of mycobacteria isolated from adverse events following BCG vaccination or TB suspected cases

Early identification of mycobacterial species is crucial for early diagnosis. PCR-multiplex method performed on randomly chosen 54 mycobacteria isolates originating from clinical samples was found to be an inexpensive, quick and reliable alternative for commercially available diagnostics tests. Although the results of gene probes identification performed by NTLDR were generally consistent with multiplex PCR, two mixed Mycobacterium bovis BCG/Mycobacterium tuberculosis infections and a single misdiagnosis of M. tuberculosis with M. bovis were found. The routine application of multiplex-PCR has the potential to make diagnostics surveillance studies feasible.

Correlation of N-acetyltransferase 2 genotype with isoniazid acetylation in Polish tuberculosis patients

Isoniazid (INH), a key agent in the treatment of tuberculosis (TB), is metabolized primarily by the genetically polymorphic N-acetyltransferase 2 (NAT2) enzyme. Patients treated with INH can be classified as fast, intermediate, and slow acetylators. The objective of this study was to explore the relationship between NAT2 genotypes and the serum concentrations of INH. Blood samples from 130 patients were taken for the analysis, and plasma INH concentrations were determined by using the high-performance liquid chromatography (HPLC) technology. Acetylation genotype was determined on genomic DNA by using an allele-specific polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. Once the NAT2 genotypes were established, patients were classified into three categories: fast, intermediate, and slow acetylators. Of the 130 patients studied, 84 (64.6%) were slow, 39 (30%) were intermediate, and 7 (5.4%) were fast acetylators. Analysis of INH concentrations in the blood of patients receiving the approximate doses of the drug revealed that, at the time intervals examined, the average concentration of INH was 2- to 7-fold higher among slow acetylators compared to fast and intermediate acetylators.

CONCLUSION

Determining mutations in the NAT2 gene enabled the identification of the INH acetylation type in patients and the genotyping results were consistent with the phenotype determined by methods of measurement of drug bioavailability.

Multiplex-PCR as an identity assay for Mycobacterium bovis BCG Moreau descendants

In the study, we assessed the identity of locally produced BCG vaccine via screening for the presence of genetic markers specific for particular Mycobacterium bovis BCG substrains - RD8, RD2, senX3-regX3, RD14, RD16, ΔRD1, DU2, a second copy of IS6110, mutation D322G in phoR, and deletions in fadD26-ppsA and Rv3887c regions. In order to increase the specificity of the multiplex-PCR test for locally produced BCG vaccine, we have modified previously developed primer sets by the introduction of a primer pair specific for deletion in Rv3887c. The modified multiplex-PCR specifically and reproducibly distinguished both BCG Moreau sublineages, and allowed, with no decrease in power, differentiation of BCG substrains of different origin. The growing knowledge of genetic differences among BCG vaccine strains enables improvements in the specificity of identity tests that will be useful both for routine release of vaccines and potential applications in clinical practice. Modified multiplex-PCR accompanied by PFGE analysis can serve as specific tools to monitor consistency in BCG manufacture.

Molecular Analysis of Strains from Tuberculosis Patients in Polish Prisons in 2004–2008. Initial Analysis of the Project

Introduction: Correctional facilities are recognised “breeding ground” for infectious diseases. As The World Health Organization reported, the incidence of infectious diseases in prison’s population is 10–100 times higher than in general population. The incidence of tuberculosis among correctional inmates in Poland in 2008 was 270/100,000, that is around 10 times higher than among non-prisoners. Materials and methods: The study included 57 M. tuberculosis isolates from patients in Polish prisons in 2004–2008 (5% of all diagnosed TB patient in Polish prisons 2004–2008). Primary isolation was performed with Löwenstein-Jensen (L-J) medium, species identification was done with the niacin test and gene probes test. Bacterial DNA was extracted from the L-J medium slants with the cetyltrimethylammonium bromide (CTAB) method. Mycobacterium tuberculosis strains were analyzed with two methods: screening for epidemiological discrimination of M. tuberculosis—spoligotyping and highthroughput—MIRU/VNTR. Results: Isolates that are grouped in clusters (33 isolates) were analyzed by means of MIRU/VNTRs. In MIRU/VNTRs all strains showed different genetic patterns. Most isolates of the prisoners were grouped into two clusters: T1 53 and H3 50. Conclusions: 1. MIRU/VNTR is a high-throughput method. 2. MIRU/VNTR is a promising method to diagnose TB transmission in Polish jails. 3. To identify the probable source of transmission, molecular analysis of strains from patients of the general population is needed.

[Molecular analysis of strains from tuberculosis patients in Polish prisons in 2004-2008. Initial analysis of the project]

INTRODUCTION

Correctional facilities are recognised breeding ground for infectious diseases. As The World Health Organization reported the incidence of infectious diseases in prison's population is 10-100 times higher than in general population. The incidence of tuberculosis among correctional inmates in Poland in 2008 was 270/100000, that is around 10 times higher than among non-prisoners.

MATERIALS AND METHODS

The study included 57 M. tuberculosis isolates from patients in Polish prisons in 2004-2008 (5% of all diagnosed TB patient in Polish prisons 2004-2008). Primary isolation was performed with Löwenstein-Jensen (L-J) medium, species identification was done with the niacin test and gene probes test. Bacterial DNA was extracted from the L-J medium slants with the cetyltrimethylammonium bromide (CTAB) method. Mycobacterium tuberculosis strains were analyzed with two methods: screening for epidemiological discrimination of M. tuberculosis - spoligotyping and high-throughput - MIRU/VNTR.

RESULTS

Isolates that are grouped in clusters (33 isolates) were analyzed by means of MIRU/VNTRs. In MIRU/VNTRs all strains showed different genetic patterns. Most isolates of the prisoners were grouped into two clusters: T1 53 and H3 50.

CONCLUSIONS

1. MIRU/VNTR is a high-throughput method. 2. MIRU/VNTR is a promising method to diagnose TB transmission in Polish jails. 3. To identify the probable source of transmission, molecular analysis of strains from patients of the general population is needed.

The capacity of Mycobacterium tuberculosis complex species and M. bovis BCG substrains specific identification - implications for optimized PCR-based diagnostics in adverse events following vaccination suspected cases

The capacities of differentiation of Mycobacterium bovis BCG from other members of M. tuberculosis complex species using PCR-RFLP, multiplex PCR, and PCR-based genomic deletion analysis approaches were compared. In the study, mycobacteria isolated from patients suspected of adverse events following vaccination with BCG, primarily classified according presence of RD1 marker as virulent and avirulent mycobacteria, were used. The PCR-based genomic deletion analysis was found the best option for mycobacteria diagnostics improvement, as it was capable precisely differentiate virulent and avirulent mycobacteria or virulent species of M. tuberculosis complex. The routine confirmation of mycobacteria species in the cases of adverse events following BCG vaccination is highly expected, especially in clinical practice of patients with primary immunodeficiency.

Granuloma of Epididymis in a Patient Treated with Intravesical BCG Therapy—Complication of BCG Therapy or Tuberculosis?

We present a case of a 72-year-old man treated for superficial bladder carcinoma from the year 2007. The patient underwent a surgical intervention for transitional cell carcinoma of the bladder, followed by intravesical BCG immunotherapy. Two years later, the right testis and epididymis were found to be enlarged. A resection was carried out. Histological examination revealed granulomatous infiltration with eosinophillic necrosis in cauda epididymis. No bacteriologic tests of the resected material were performed. Due to a suspected BCG infection or TB, the patient was transferred to the Institute of Tuberculosis and Lung Diseases in Warsaw, for pulmonary evaluation. Chest X-ray, chest CT scan and bronchoscopy were performed but apart from scars in the bronchi suggesting a history of TB, they did not contribute to the diagnosis. Tuberculin skin test was 21 mm. Diagnosis was determined by spoligotyping which found genetic material of Mycobacterium tuberculosis in specimens preserved in a paraffin block. Tuberculosis of the right epididymis and past pulmonary tuberculosis were diagnosed. The patient was treated with rifampin, isoniazid and pyrazynamid.

Interferon-Gamma Assay T-SPOT.TB in the Diagnostics of Latent Tuberculosis Infection

Introduction: Diagnostics of latent tuberculosis infection (LTBI) has been based on a century-old tuberculin skin test (TST). However, a positive reaction can result not only from infection with Mycobacterium tuberculosis, but also from BCG vaccination or cross-reaction with nontuberculous mycobacteria. T-SPOT.TB assay is a new test to diagnose tuberculosis infection by measuring in vitro T-cell interferon-gamma release in response to two Mycobacterium tuberculosis-specific antigens: ESAT-6 and CFP-10. Material and methods: T-SPOT.TB assay was performed on samples of whole blood (n = 137) from March to September 2010. Tuberculin skin test was carried out in 96 participants. A positive TST result was considered to be an induration of 10 mm or more. Results: Of the 137 patients tested, T-SPOT.TB assay results were positive in 37 (27%), negative in 98 (71.5%) and indeterminate in only 2 (1.5%) persons. We analyzed T-SPOT.TB and TST results in 96 patients who were subjected to both tests. Concordance between T-SPOT.TB and TST results (a 10-mm skin reaction interpreted as positive) was 79%. Fifteen (15.6%) patients had a positive TST result and a negative T-SPOT.TB, and 5 (5.2%) patients had a negative TST result and a positive T-SPOT.TB. We observed a good correlation between positive T-SPOT.TB results and the diameter of induration of ≥15 mm in TST results. Conclusions: T-SPOT.TB offers a more accurate approach than TST in the identification of tuberculosis infection. The study showed that the test T-SPOT.TB is a good diagnostic tool in identifying persons with tuberculosis infection. For a full confirmation of this assessment, it is necessary to examine more cases.

[Granuloma of epididymis of patient treated with intravesical BCG therapy--complication of BCG therapy or tuberculosis?]

We present a case of 72-year old man treated from 2007 for superficial bladder carcinoma. Patient had undergone surgical intervention for transitional cell carcinoma of the bladder, followed by BCG therapy. Two years later enlarged right testis and epididymis was observed. A resection was carried out. Histologic examination revealed in epididymis cauda granulomatous infiltration with eosinophilic necrosis. No bacteriologic tests of resected material were performed. Suspecting BCG infection or TB patient was referred to the Institute of Tuberculosis and Lung Diseases in Warsaw for pulmonary evaluation. Chest X-ray, chest CT scan and bronchoscopy were performed but beside revealing scars in bronchi suggesting a history of TB did not contribute to the diagnosis. Tuberculin skin test was 21 mm. Diagnosis was determinated by spoligotyping which found bacille of Mycobacterium tuberculosis in specimen preserved in paraffin block. Tuberculosis of right epididymis and past pulmonary tuberculosis was diagnosed. Patient was treated with rifampin, isoniazid and pirazynamide.

[Interferon-gamma assays T-SPOT.TB for the diagnosis of latent tuberculosis infection]

INTRODUCTION

The diagnosis of latent tuberculosis infection (LTBI) is currently based on the century-old tuberculin skin test (TST). However a positive reaction can result from infection by Mycobacterium tuberculosis, BCG vaccination or cross-reaction with nontuberculous mycobacteria. T-SPOT.TB assay is a new test to diagnose tuberculosis infection by measuring in vitro T-cell interferon gamma release in response to two Mycobacterium tuberculosis-specific antigens: ESAT-6 and CFP 10.

MATERIAL AND METHODS

T-SPOT.TB assay has been performed on whole blood samples (n = 137) from March to September 2010. A tuberculin skin test result was available for 96 of participants. A positive TST result was considered if the induration was 10 mm or more.

RESULTS

Of the 137 patients tested, T-SPOT.TB assay results were positive in 37 (27%), negative in 98 (71.5%) and indeterminate in only 2 (1.5%) persons. We analyzed T-SPOT.TB and TST results in the 96 patients for whom both test were available. Concordance between T-SPOT.TB and TST results (10 mm skin reaction interpreted as positive) was 79%. Fifteen (15.6%) patients had a positive TST result and a negative T-SPOT.TB and 5 (5.2%) patients had a negative TST result and a positive T-SPOT.TB. We observed good correlation between positive T-SPOT.TB results and the size of induration ≥ 15 mm in TST results.

CONCLUSIONS

T-SPOT.TB offers a more accurate approach than TST for identification tuberculosis infection. The study shows that the test T-SPOT.TB is a good diagnostic tool in identifying persons with tuberculosis infection. For full confirmation of this assessment, it is necessary to examine more cases.

[Transmission of Mycobacterium tuberculosis among household contacts of patients with tuberculosis]

OBJECTIVE

The aim of this study was estimation of usefulness of two molecular methods for Mycobacterium tuberculosis typing in the epidemiological research of tuberculosis (TB). We determined molecular patterns of M. tuberculosis strains isolated from 66 patients, members of 29 families living in 9 voivodeships of Poland. We also analysed drug susceptibility of the strains as well as some demographic characteristics of the patients.

METHODS

The genotype analysis of the 66 clinical isolates was performed by using spoligotyping and IS6110-Mtb1/Mtb2 PCR.

MAIN OBSERVATIONS

Of the 29 families examined in this study, in 23 each family member was infected with the same M. tuberculosis strain. Three drug-resistant strains and two members of the Beijing family were identified.

RESULTS

We found that strains within each of the 23 families had the same genetic patterns, whereas those of the strains identified in the rest 6 families were different. Among those 6 families, in 3 differentiation of the strains was obtained with both spoligotyping and IS6110-Mtb1/Mtb2 PCR analysis, while in another 3 only with spoligotyping method.

CONCLUSIONS

Based on the results from this study, the two genotyping methods used were demonstrated as an efficient approach for investigating the epidemiological relatedness of TB cases.

[Detection of mutation in NAT II gene as a method of determination of izoniazyd (INH) acetylation type in human population]

INTRODUCTION

Isoniazid (INH) is a drug widely used in the treatment of tuberculosis. INH is metabolized to acetylisoniazid by N-acetyltransferase (NAT) in the liver. The rate of INH acetylation is genetically determined. NAT isozymes are encoded at 2 loci; one encodes NAT1, formerly known as the monomorphic form of the enzyme, while the other encodes the polymorphic NAT2, which is responsible for individual differences in the ability to acetylate certain compounds. The objective of the present study was to apply the genotyping of the fast and slow acetylators for personalized therapeutic dose.

MATERIAL AND METHODS

Plasma concentrations of INH were determined with biological method in the authors modification. This method warrants high accuracy and secured repeatable results. Genomic DNA was isolated from the blood samples. DNA extracted by Blood DNA Kit and amplified by PCR by Spurr [1] with two primers. PCR product was cut separately with 4 different restriction enzymes: Dde1, Kpn1, Tag1, and BamH1.

RESULTS

Four different NAT 2 alleles were detected in the study population. The presence of any 2 mutant alleles defines the slow-acetylator genotype, whereas rapid acetylators have 1 or 2 wild-type NAT2*4 alleles.

CONCLUSION

On the basis of our results we suggest the using of NAT 2 genotyping for discrimination of the fast and slow acetylators in monitoring of tuberculosis therapy.