The strain of tuberculous mycobacteria called Mycobacterium caprae infects many wild and domestic animals; however, because of its zoonotic potential and possibility of transmission between animals and humans, it poses a serious threat to public health. Due to diagnostic limitations regarding...
Introduction: The risk of Mycobacterium tuberculosis complex (MTBC) infection is correlated with the concentration of infectious particles and exposure time. In closed populations, healthy people staying in very frequent, close and prolonged contact with a smear-positive person, become infected and represent another link in the chain of transmission of the disease. Therefore, in the fight against tuberculosis, an important element is quick identification of the patient and potentially infected people from his environment. In epidemiological investigation of tuberculosis (TB), family members are brought under special control as they are particularly exposed to transmission of infectious diseases. Material and methods: The study included 150 patients with bacteriologically confirmed tuberculosis who were members of 59 families. In the years 2003−2013 this population represented all TB cases detected in Poland in a family environment.Three PCR-based genotyping methods: spoligotyping, IS6110-Mtb1-Mtb2 PCR and MIRU-VNTR typing were used. Results: Of 150 patients, 138 could be assigned to intra-household transmission on the basis of identical DNA fingerprints upon a combined typing approach. For 12 patients in 6 households, the M. tuberculosis isolates were clearly distinct in individual analysis—IS6110-Mtb1-Mtb2 PCR, spoligotyping or MIRU-VNTR typing or in three genotyping methods, suggesting that these patients were infected by the sources in the community. Conclusions: The analysis confirmed the transmission of tuberculosis among members of 53 families. In the remaining 6 families the source of infection were people outside the households. In all families with young children, strains isolated from them have identical DNA patterns as strains obtained from their adult caregivers. To confirm the transmission of TB in the study population of patients, epidemiological analysis required the addition of a genotyping methods characterised by high discriminatory power.
Cutaneous tuberculosis (CTB) is a very rare disease and accounts for only 1–2% of cases of extrapulmonary tuberculosis (EPTB). Due to the variety of its clinical manifestations, the uncharacteristic appearance of its lesions, resembling other dermatoses in the early stages, and the limited experience of clinicians due to the rarity of CTB, diagnosis is very difficult. Particularly noteworthy is the fact that most cases of EPTB, including skin tuberculosis (TB), can be a manifestation of systemic involvement. In this paper, we present a case of an immunocompromised patient who was diagnosed with CTB almost a year after the first dermatological lesions were located on the lower extremities. At the same time, due to respiratory symptoms, a diagnosis of pulmonary TB (PTB) was made, and radiological and microbiological confirmations were obtained.
Introduction: The control of tuberculosis (TB) requires methods for rapid detection and tracing sources of infection, so that further transmission can be arrested. Recent developments in molecular biology have resulted in techniques that allow prompt identification and tracking specific strains of M. tuberculosis as they spread through the population. Most of these techniques take advantage of M. tuberculosis DNA polymorphism and are based on various repetitive DNA elements as genetic markers. Each method yields strain-specific genetic profiles (fingerprints). Strains showing identical fingerprints are referred to as clustered and are usually associated with recent transmission, whereas strains whose fingerprints are unique are presumed to represent remote transmission, a reactivation of infection acquired in the distant past. Material and methods: In recent years, spoligotyping has become one of the most widely used genotyping method for epidemiological studies of TB. Spoligotyping is a PCR-based method allowing to analyze strain-dependent polymorphisms observed in spacer sequences present within the direct repeat (DR) genomic region of M. tuberculosis complex strains. Spoligotyping provides some important advantages over other genotyping techniques. These are simplicity, rapidity, high reproducibility and stability of the results, with the latter being expressed in a simple digital pattern, readily named and databased, and the ability to perform spoligotyping directly on clinical samples, without the need for prior culture. However, spoligotyping has relatively low discriminatory capacity, which makes it necessary to use secondary fingerprinting methods to prove clonality between isolates. Results: The aim of this study was to evaluate the usefulness of spoligotyping in epidemiological investigations of TB by analyzing 16 isoniazid-resistant M. tuberculosis strains isolated from patients with pulmonary TB in the central region of Poland. A total of 11 distinct spoligopatterns were obtained. 9 isolates were represented by a unique pattern, whereas 7 were clustered in 2 groups of 5 and 2 isolates, respectively. When compared with an international spoligodatabase SpolDB4, 13 isolates shared already described spoligotypes, whereas 3 did not match any existing spoligopattern in database and were defined as orphans. Spoligotyping overestimated the number of clustered isolates in one of its two clusters when compared to IS6110 Mtb1/ /Mtb2 PCR. Strains clustered using the latter method were assumed to be closely epidemiologically related. Conclusions: This report demonstrates the utility of spoligotyping as an initial screening technique, to be supplemented by another typing method of greater discriminatory power, such as the IS6110 Mtb1/Mtb2 PCR in order to better recognize the epidemiological links between TB patients.
Data on the coincidence of tuberculosis (TB) and COVID-19 are limited, and previous observations are based on the results of just a few studies, which has led to polarized views on the course of infection with SARS-CoV-2 in patients with active TB. We present the first two cases of TB and COVID-19 coinfection in the population of patients in Poland, diagnosed shortly after the outbreak of the global pandemic. In the first patient, TB was very advanced at the time of infection with SARS-CoV-2. From the third day of hospitalisation, respiratory failure was increasing, with no improvement after the use of high-flow oxygen therapy and mechanical ventilation. On the seventh day of hospitalization, the patient died. In the second presented case, therapeutic success was achieved despite the coincidence of COVID-19, infection with HIV, and extrapulmonary and pulmonary TB. The patient had symptoms of renal failure and the SARS-CoV-2 infection was mild and asymptomatic. Because both patients were in the care of a homeless shelter, a molecular epidemiological investigation was carried out. Different DNA profiles of Mycobacterium tuberculosis complex isolates detected in clinical materials from patients ruled out the transmission of tuberculosis. Based on our analysis, it is impossible to clearly define the influence of active TB on the course of SARS-CoV-2 infection. We can only suggest that coinfection is particularly dangerous for socially disadvantaged people, the elderly, and people with other comorbidities. In the coming years, a negative impact of the current pandemic on control programmes will be observed for many infectious diseases, including TB.
Non-tuberculous mycobacteria (NTM) are ubiquitous organisms, of which some, especially those of the Mycobacterium avium complex (MAC), may be opportunistic animal and human pathogens. Infection with NTM can interfere with tuberculosis (TB) diagnosis and induce zoonoses, especially in immunocompromised individuals. Diseases caused by NTM have become more readily recognized; however, they are likely still underestimated. In this study, we identified and genotyped Mycobacterium avium strains that were isolated during TB monitoring among free-living carnivorous animals from southeastern Poland. In 2011–2020, lymph node samples from 192 such animals were tested for mycobacteria. A total of 41 isolates of M. avium strains were detected with the use of IS901, IS900, IS1245, and mycobacterial interspersed repeat unit–variable number tandem repeat (MIRU-VNTR) identification. Thirty-three were identified as M. avium subsp. avium. These strains were derived from 1 beech marten (Martes foina), 1 common buzzard (Buteo buteo), 2 European badgers (Meles meles), 3 wolves (Canis lupus), and 26 red foxes (Vulpes vulpes). One strain isolated from a wolf was identified as M. avium subsp. hominissuis. The results show the widespread occurrence of MAC bacilli in the studied environment and additionally comprise new data on the molecular characteristics of M. avium subspecies carried by free-living southeastern Polish carnivores.