International Journal of Mycobacteriology最新文献

Background: Making a preliminary diagnosis using X-ray methods for the study of resistant and resistant tuberculosis (TB) will help to make a preliminary diagnosis and determine further tactics for the treatment of TB, even with limited resources for microbiological diagnosis of drug resistance of TB. The present study was aimed at identifying chest X-ray differences between susceptible and resistant TB.

Methods: A prospective cohort study of data from all consecutive patients with culture-confirmed pulmonary TB admitted during the year to the Kharkiv TB Dispensary No. 1 in Kharkiv, Ukraine.

Results: One hundred and sixty-eight patients with lung TB were examined. Patients were divided into two groups: 1^st patients with pulmonary TB with resistance of Mycobacterium tuberculosis (MTB) to at least isoniazid and rifampicin (resistant TB) and 2^nd pulmonary TB with preserved susceptibility of MTB to anti-TB drugs (susceptible-TB). Patients of 1^st group often had lesions in two lobes of the lungs 31.1% and one lung 43.3% versus 15.4% and 2.6% of patients with susceptible TB (P < 0.001). In addition, more than 3 cavities in the lungs 45.5% were significantly more often observed in patients with resistant TB versus 7.9%-the 2^nd group (P < 0.001). Smaller cavities were observed in patients with susceptible TB up to 1.99 cm 74% versus 35.2% in 1^st group (P < 0.001). We did not observe any significant radiological features depending on the right or left lung, as well as the lobar localization of the TB process.

Conclusions: For resistant forms of TB, radiologically, a more widespread TB process in the lungs with the presence of a larger number of cavities and their larger size against a background of a more pronounced clinical picture and mycobacterium excretion than with susceptible TB is characteristic.

Spinal epidural abscess (SEA) is a rarest form of spinal infections and is characterized by the presence of pus in the space between the dura mater, and the osseoligamentous confines of the vertebral canal. This can cause spinal injury due to direct compression or local ischemia. The major etiology of SEA is bacterial and tuberculous in endemic regions. The incidence of fungal spinal abscess is relatively low and <5% of SEA is attributable to fungi. We, here, report a case of 77-year-old known patient of chronic renal disease on hemodialysis that presented with low-back pain for 15 days and was subsequently diagnosed with SEA by magnetic resonance imaging, and causative organism was identified as Candida by culture. The abscess was surgically drained after laminectomy. The patient improved with surgery and antifungal treatment.

Difficult-to-treat mycobacterial infections are increasing globally. There is an urgent need of new treatment alternatives for multidrug-resistant Mycobacterium tuberculosis (MTB), as well as nontuberculous mycobacteria such as the Mycobacterium abscessus complex (MABC) and Mycobacterium avium complex (MAC). Recently, new carbapenems and combinations of carbapenems with β-lactamase inhibitors have become available, but activity data in vitro against mycobacteria are so far scarce. Therefore, we performed a systematic review collating the minimum inhibitory concentrations (MICs) of carbapenems, with or without a β-lactamase inhibitors for MTB, MABC, and MAC. The databases PubMed and Web of Science were searched for the relevant articles in English up until September 21, 2022. Screening of studies was performed by two independent reviewers. MIC data by recommended methods with at least five individual MICs were included. Data were reported as MIC range, MIC₅₀, modal MIC, and/or histograms when individual MICs were available. The study protocol was registered at PROSPERO (CRD42021258537). After screening, a total of 75 studies with MIC data for carbapenems with or without β-lactamase inhibitors were included in the review. For MTB, the oral carbapenem tebipenem combined with the β-lactamase inhibitor clavulanic acid resulted in the most significant reduction of MICs. For MABC, the addition of avibactam to tebipenem resulted in a 64-fold reduction of modal MIC. Data were insufficient for the analysis of MAC. Carbapenems, and in particular the novel oral compound tebipenem, in combination with clavulanic acid for MTB and avibactam for MABC may be an untapped potential for difficult-to-treat mycobacterial infections.

Background: Bedaquiline is a core drug with an optimized background regimen for treating drug-resistant tuberculosis (DR-TB) patients. One of the adverse effects of bedaquiline is QT-corrected (QTc) interval prolongation. TB patients with diabetes mellitus (DM) are more likely to develop QTc interval prolongation during TB treatment than those without DM. This study aimed to correlate baseline electrolyte levels (potassium, calcium, and magnesium), thyroid-stimulating hormone (TSH), body mass index (BMI), blood glucose, glycated hemoglobin (HbA1c), and pretreatment QTc interval among patients with diabetic DR TB who received regimens containing bedaquiline.

Methods: It was a prospective study with a cross-sectional design. Blood samples, BMI, and electrocardiogram were collected at baseline before starting the regimen for DR-TB. Pearson correlation was used to correlate between baseline electrolyte level, TSH, BMI, complete blood count, blood glucose, HbA1c, and pretreatment QTc interval.

Results: Seventy-two DR-TB patients met the inclusion criteria, half with DM. The blood glucose and HbA1c were significantly higher in patients with DM. Pretreatment QTc interval was similar between the two groups. Levels of calcium, magnesium, TSH, blood glucose, and BMI were not correlated with pretreatment QTc interval. There was a correlation between baseline potassium and HbA1c levels with pretreatment QTc interval (P < 0.05; r = 0.357 and r = -0.376, respectively). Baseline potassium level correlates with the pretreatment QTc interval in those without DM.

Conclusion: Baseline HbA1c and potassium levels correlate with pretreatment QTc interval among DR-TB patients with DM. Our study indicates the importance of monitoring HbA1c and potassium levels during DR-TB therapy containing bedaquiline for early detection of QTc prolongation.

Background: The immunomodulatory effects of Vitamin D expand to induce the synthesis of an antimicrobial peptide, cathelicidin. There is evidence showing altered levels of cathelicidin in tuberculosis (TB). It has been suggested that Vitamin D-mediated antimicrobial activity depends on its ability to induce cathelicidin. The present study was designed to assess the alterations in serum anti-microbial peptide cathelicidin and 25-hydroxy Vitamin D levels in patients with newly diagnosed pulmonary TB at different treatment times and to study the association between serum Vitamin D levels and cathelicidin.

Methods: Serum 25-hydroxyvitamin D and cathelicidin levels were estimated in 147 patients with newly diagnosed pulmonary TB at different times: at the start of anti-tubercular treatment, end of the intensive phase of treatment, and at the end of treatment.

Results: There was a statistically significant difference between the levels of serum 25-hydroxyvitamin D and serum cathelicidin at different treatment periods. However, no significant correlation was found between serum Vitamin D and cathelicidin levels or between serum Vitamin D and cathelicidin levels with infectiousness in patients with pulmonary TB.

Conclusion: Serum Vitamin D levels and serum cathelicidin levels were significantly reduced at diagnosis, and there was an incremental increase following treatment. However, there was no correlation between the levels of serum cathelicidin and serum Vitamin D or with the infectiousness of the illness.

Background: The nutrient medium effects on the quality of the matrix-assisted laser desorption/ionization-time-of-flight (MALDI-ToF) mass spectra. The standard library includes spectra of microorganisms of the family Mycobacteriaceae grown on the Lowenstein-Jensen and Middlebrook Media. There are new methods for culturing microorganisms from this group, including inoculation on chromogenic media.

Methods: The study included 240 strains of NTM isolated from patients during tuberculosis examination. The inoculation of the biological material was carried out on solid culture media of Lowenstein-Jensen and universal chromogenic media. Identification of bacteria from both types of media was performed by MALDI-ToF mass spectrometry (Bruker Daltonik GmbH, Germany). Analysis of protein spectra was performed.

Results: For all strains, the spectra revealed both coinciding peaks (regardless of the cultivation medium) and significant differences, including the complete absence of some peaks depending on the medium. The results of a greater divergence of peaks in mass and intensity were obtained for slow-growing species than for fast-growing species. For all analyzed cultures, the number of peaks in the mass spectra was significantly higher when cultivating on a universal chromogenic medium than on a Lowenstein-Jensen medium.

Conclusions: The use for NTM cultivation of a universal chromogenic medium makes it possible to obtain acceptable identification results by MALDI-ToF mass spectrometry using a standard library.

Background: Understanding the protein's subcellular localization and secretory nature can greatly improve the target identification for diagnostic assays and drug discovery, although their identification in laboratory experiments is a time-consuming and labor-intensive process. In order to identify proteins that could be targeted for therapeutic intervention or the development of diagnostic assays, we used a variety of computational tools to predict the subcellular localization or secretory nature of mycobacterial proline-glutamate/proline-proline-glutamate (PE/PPE) proteins.

Methods: PSORTb version 3.0.3, TBpred, and Gpos-mPLoc analyses were performed on 30 selected PE/PPE protein sequences, while, SignalP 6.0, SignalP 5.0, Phobius, PSORTb version 3.0.3 and TBpred were used for signal sequence predictions.

Results: Gpos-mPLoc and TBpred had the highest concordance for extracellular prediction, while PSORTb and TBpred had the highest concordance for prediction of membrane localization. The tools for predicting the secretory nature of proteins had little agreement.

Conclusion: Multiple computational tools must be considered to provide an indication of the subcellular localization of PE/PPE proteins. Laboratory experiments should be used to confirm the findings of the tools.

Background: Leprosy is a chronic granulomatous infection caused by Mycobacterium leprae or Mycobacterium lepromatosis and mainly affects the skin and peripheral nerves. Although treatable, its early intervention can significantly reduce the occurrence of disability. India accounts for more than half of new cases globally. This study was undertaken to better understand the clinical traits of newly diagnosed cases in a tertiary facility of Western Uttar Pradesh, and a few from Madhya Pradesh and Uttarakhand.

Methods: The observational prospective study was carried out on all the newly diagnosed leprosy cases who visited the Outpatient Department of ICMR-National JALMA Institute for Leprosy and Other Mycobacterial Diseases, Agra, during October 2019-December 2022. After obtaining answers to a prestructured questionnaire with their consent, participants were enrolled in the study and underwent clinical examination and a slit-skin smear test.

Results: A total of 56 cases were investigated, and among them, 20 (35.7%) and 36 (64.3%) women and men, respectively, had positive contact with persons affected by leprosy either within family, friends, or neighbors. It is observed that due to the delayed detection of leprosy cases, paucibacillary (PB) patients converted into multibacillary (MB) patients, and the number of MB cases is much higher compared to PB cases.

Conclusion: Leprosy instances continue to spread frequently from sick to healthy people indicating continued transmission of leprosy in society. Multidrug therapy in the management of leprosy cases is effective; however, early diagnosis of PB cases is still a challenge and needs to be addressed on priority.

Background: Nontuberculous mycobacteria (NTM) are increasingly identified as causes of protracted pulmonary infections. Antibiotic susceptibility testing requires microdilution methods, which are often unavailable in laboratories in resource-poor settings. We report cumulative antibiograms for the most frequently isolated clinical pulmonary NTM from Pakistan to inform empiric antibiotic management of initial NTM infections.

Methods: We analyzed data from 2018 to 2022 for the most frequently isolated and clinically relevant NTM isolated from respiratory specimens, i.e., Mycobacterium avium complex (MAC), Mycobacterium abscessus group (MAG), and Mycobacterium kansasii (MK). Antibiograms were developed using the Clinical Laboratory Standards Institute's M39ED5 standard. Percentage susceptibilities and 95% confidence intervals (CI) were calculated.

Results: Over 4 years, 529 NTM, comprising 209 MAC, 249 MAG, and 71 MK were analyzed. For MAC and MAG, where clarithromycin (CLR)-based regimens are recommended, CLR was active for 94.8% (95% CI 91.3-96.9), and 77.5% (95% CI 71.4-82.7) isolates, respectively. Combination regimens comprising 3 active drugs CLR + linezolid (LZD) + moxifloxacin for MAC and CLR + LZD + Amikacin for MAG had 98.4% (95% CI 95.9-99.4) and 68.9% (95% CI 62.3-74.8) coverage for pulmonary disease, respectively. For MK, 91.5% (95% CI 82.8-96.1) isolates were susceptible to rifampin (RIF), with a combination of RIF + CLR covering 88.7% (95% CI 79.3-94.2) of MK pulmonary infections, respectively.

Conclusions: These data can inform empiric treatment guidance for the most common NTM pulmonary infections, i.e., for MAC, MAG, and MK disease in Pakistan.

Background: Nontuberculous mycobacterial (NTM) pulmonary disease (PD) has rapidly increased globally. The characteristics and comparison of rapidly growing mycobacteria PD (RGM-PD) and slowly growing mycobacteria PD (SGM-PD) are still unclear.

Methods: Our study enrolled 31 NTM-PD patients. Clinical data, including baseline, symptoms, underlying disease, laboratory tests, metagenomic next-generation sequencing (mNGS) results, radiological images, treatment, and outcome were recorded and analyzed.

Results: Of the 31 patients with NTM-PD, 22 patients were female and 9 were male. It included 11 RGM-PD and 20 SGM-PD. There was no difference in age (P = 0.425) and body mass index (P = 0.152) between the two groups. The common respiratory diseases in prevalence included bronchiectasis and chronic obstructive pulmonary disease. Three patients had positive results of T-SPOT tuberculosis (TB), and none had positive Xpert-Mycobacterium tuberculosis/rifampin results. On admission, patients were symptomatic and included cough/sputum production, fever, weight loss, fatigue, and hemoptysis. In comparison to RGM-PD, patients with SGM-PD had a greater chance of experiencing fatigue (P = 0.012). No significance was found in serum biomarkers between RGM and SGM-PD, including CD4/CD8 ratio, white blood cells, neutrophils, lymphocytes, procalcitonin, ferritin, C-reactive protein, and erythrocyte sedimentation rate. No liver or kidney impairment was found. Patients with RGM-PD were more likely to have right lower lobe (RLL) impairment (P = 0.021) and a cavity characteristic (P = 0.012). All 31 cases had positive mNGS results. The duration of mNGS was shorter than conventional methods (3.4 ± 0.7 vs. 26.4 ± 20.9, P < 0.001).

Conclusions: Patients with SGM-PD were more likely to experience fatigue. The cavity and RLL involvement were more frequent in the RGM-PD. mNGS increases the identification of NTM specimens and complements the capabilities of conventional methods.