Acid-fast Research Articles

A unique case of laproscopic port site tuberculosis.

We report a case of 27 years old lady who presented after 04 weeks of laproscopic cholecystectomy, with purulent discharge from 03 port sites most likely due to improper sterilization of re-usable laproscopic instruments. Patient was initially managed conservatively by repeated incision and drainage and multiple antibiotics including second line drugs against atypical mycobacterium were prescribed but infection did not settle. Her routine bacterial cultures and acid fast bacillus (AFB) stains were negative. After 07 months patient started developing abscesses in surrounding primary port sites and it was finally decided to excise the discharging sinus tracks and sent for histopathology. Histopathology confirmed tuberculosis as it showed epithelioid granulomas. Patient was started with standard first line anti tuberculous treatment (ATT) to eradicate the disease and she became alright after 06 months of ATT.

Vitamin D as Supplementary Treatment for Newly Diagnosed Pulmonary Tuberculosis patients

Objective: To compare vitamin D with placebo in patients with pulmonary tuberculosis in terms of clinical improvement and sputum conversion. Materials And Methods: This is a prospective randomized, double blind, placebo controlled comparative study conducted for a period of 12 weeks in a tertiary care centre in south India. Total Subjects were 60 new cases of pulmonary tuberculosis who are getting TB treatment initiation, Subjects were randomly allocated into two groups, group A and group B comprising of 30 patients in each group. Group A received vitamin D and group B received placebo. Dosage of vitamin D was 0.25mg/day, given in initial six weeks of antituberculosis drug therapy. Serum level of 25-hydroxyvitamin D was measured at time of diagnosis and at 8 weeks of anti-tuberculous therapy. Measurements of haemoglobin, leukocyte count and serum calcium were done at beginning and repeated at 6th, 8th and 12 weeks. Acid fast bacilli were examined at beginning and on 6th, 8thand 12 weeks. Primary outcome was evaluation of conversion time of sputum smear; secondary outcome was clinical improvement as assessed by TB score. Results: There is no significant difference in mean values of age, haemoglobin level, calcium level,serum Vitamin D, TB score and total lymphocyte count in both groups at start of study.There was no statistical difference in serum calcium level, haemoglobin level and total lymphocyte level at end of study. Mean serum vitamin D level at 8th week of treatment was 27.83±7.09ng/dl in group A and 18.83±2.27 in group B, there was statistically significant difference between two groups. Sixth week sputum conversion in 30 subjects of vitamin D group is 100% and in placebo group, it is 76.7%, which was statistically significant. Conclusion: Supplementary vitamin D when added to first line anti-tuberculous drugs results in shorter conversion time and less severe TB clinical manifestation without any manifestations of hypercalcemia. Therefore, it is recommended to add vitamin D as supplementary treatment to first-line anti-tuberculous drugs in treatment course of active pulmonary TB.

Tuberculosis and HIV co-infection among miners at selected mining sites in Migori County, Kenya

Tuberculosis (TB) disease is caused by acid-fast bacilli called Mycobacterium tuberculosis. The emergence of drug-resistant TB variants as well as co-infection with the Human Immunodeficiency Virus (HIV) have complicated treatment for TB. Kenya currently implements TB screening and HIV testing for all patients and their caretakers, regardless of their reason for visiting the hospitals. Drug resistance is tested in all HIV-positive TB suspects to guide the choice of drugs in cases of TB-HIV co-infection and minimise delays in treatment initiation. These services are, however, confined to the health facilities, and all those who do not visit the hospitals are missed. The objective of our study was to evaluate TB missed opportunities among the mining community of Osiri-Matanda gold mines in Nyatike sub-county, Migori County, Kenya. Community health outreaches were conducted in collaboration with the Ministry of Health. Demographic information was recorded for all clients consenting to the study. HIV testing was done using the HIV rapid testing kits. Sputum samples were tested in the local laboratory using Ziel-Neelsen (ZN) staining. All TB-positive outcomes were further tested using GeneXpert MTB/RIF to determine whether or not they were resistant to Rifampicin. A total of 297 participants were enrolled in the study. Among these, 49.5% were males and 50.5% were females. The youngest participant was 15 years old, while the oldest was 63 years old. A 15.5% TB prevalence was found after testing, with the age range of 35–44 having the highest prevalence at 39%. 71.7% of TB infections were male, while 28.3% were female. HIV-TB co-infections accounted for 37% of cases. None of the TB cases were RIF-resistant. This data shows that males are more at risk of TB and HIV infections than females. Collaborative health outreaches that include screening and testing for both TB and HIV could help in early detection and minimise missed opportunities.

Evaluation of Recurrent Lymphadenitis after Six Months Anti-Tuberculous Therapy

Background: Recurrence or persistence of tuberculous lymphadenitis even after treatment occurs due to paradoxical immune response, non-tubercular mycobacterial (NTM) infection, drug resistance tuberculosis or because of misdiagnosis. In these situations sometimes the patients are asked to continue category-1 more than six months on the basis repeat fine needle aspiration cytology (FNAC) findings. This study evaluated the cause of persistence or appearance of new lymph node after anti-TB category-1. Methods: This observational study was done from January, 2013 to March, 2014 after getting ethical clearance from Bangabandhu Sheikh Mujib Medical University (BSMMU). Patients who had persistent or new lymphadenitis after completing anti-TB category-1 for six months were selected. After analysis of treatment records, patients were selected for either FNAC or biopsy with local surgical clearance. Cyto/histopathological analysis, AFB stain (LED fluorescent), AFB culture (MGIT and L-J media) and GeneXpert test was done. Follow-up of the patients were done after two weeks and six months of FNA/surgery. Results: Thirty-two patients (M/F=11/21) with mean age 25(±12) years were investigated. Altogether 26 cases (81.25%) Journal of Bangladesh College of Physicians and Surgeons Vol. 41, No. 4, October 2023 were confirmed as tuberculous lymphadenitis and six (18.75%) were non-tuberculous (03 lymphomas, 01 sarcoidosis, 01 reactive lymphadenitis and 01 pyogenic abscess). Among the TB patients, granuloma was present in 23 cases (88.46%) (FNA-07, biopsy-16). Twenty-three (88.46%) cases were GeneXpert positive, comprising 21 rifampicin sensitive and 02 rifampicin resistant. One rifampicin resistant case was confirmed by culture and the remaining 25 were culture negative. One case was AFB stain positive and no NTM was found in AFB culture. After surgery, rapid healing was observed within two weeks among tuberculous lymphadenitis patients. Conclusions: Persistent granuloma after anti-TB category-1 does not indicate active tuberculosis if it is culture negative. It may occur due to immunological reaction against dead bacilli in deep seated sinus. Local surgical clearance results rapid recovery and other diagnosis should be excluded without further continuation of anti-TB category-1. J Bangladesh Coll Phys Surg 2023; 41(4): 262-268

Non-tuberculous mycobacterial disease associated with Mycobacterium montefiorense in salamanders.

Mycobacterium montefiorense is one of the causes of non-tuberculous mycobacterial infections in moray eels and salamanders. Although M. montefiorense infection could be a threat to salamanders, little information is available regarding this pathogen and associated infection. This study aimed to provide fundamental information regarding M. montefiorense and its infection in salamanders. Nine M. montefiorense strains isolated from three species of salamanders, namely, Japanese black salamander (Hynobius nigrescens), Hakuba salamander (H. hidamontanus), and Tohoku hynobiid salamander (H. lichenatus), between 2010 and 2018, were characterized based on phenotypic and genetic examination. We also pathologically observed salamanders infected with the M. montefiorense strains, including Hakuba salamanders and Tohoku hynobiid salamanders. The microbiological and chemical characteristics of the M. montefiorense salamander and an eel strain (reference strain) matched. Susceptibility testing for antimicrobials suggested that clarithromycin may be effective. Regarding disinfectants, phtharal, peracetic acid, glutaral, sodium hypochlorite, and benzalkonium chloride may be effective. Phylogenetic analyses revealed that the strains isolated from salamanders in 2014 and 2018 were genetically closely related, which could indicate an outbreak. The main gross findings in infected salamanders include skin ulcerative lesions or nodules in the enlarged liver. Microscopically, multifocal to coalescent granulomatous lesions composed of massive macrophages containing numerous acid-fast bacilli were prominently observed in the liver. This study contributes to our understanding of the genetic diversity and phenotypic characteristics of M. montefiorense, as well as the pathology of the infection.

Tubercular cold abscess: uncommon location of a common disease

Musculoskeletal tuberculosis is not rare to find, but presence of the disease and such extensive involvement at an unusual site without much of bone involvement is rare. Reporting a case of isolated cold abscess in a 60-year-old male with evening rise of temperature, weight loss and diffuse swelling in his leg involving almost entire anterior aspect of leg. Magnetic resonance imaging (MRI) was advised to investigate further and revealed large focal intra medullary heterogenous collection and large lobulated juxtacortical collection in tibialis anterior muscle. Hematoma/organised abscess, incision and drainage was done and sent for Z-N staining which showed acid-fast bacilli. Anti-tubercular treatment was administered- isoniazid (H), rifampicin (R), ethambutol (E), pyrazinamide (Z). Outcome was favourable and patient become symptomatic better. Drainage of the cold abscess and antitubercular coverage produced good results in this rare presentation of tuberculosis.

Xpert MTB/RIF assay for the differential diagnosis between sarcoidosis and tuberculosis intrathoracic lymphadenopathy

BackgroundThe aim of this study was to evaluate the role of Xpert MTB/RIF assay in the detection of Mycobacterium tuberculosis for differentiating tuberculosis intrathoracic lymphadenopathy from sarcoidosis intrathoracic lymphadenopathy.MethodsThe patients who were suspected to having sarcoidosis or tuberculosis intrathoracic lymphadenopathy at the Shanghai Pulmonary Hospital between October 1, 2020 and June 30, 2021 were retrospectively evaluated in this study. All patients underwent endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) and Xpert analysis. Differences in clinical and radiological features were recorded. The diagnostic performances of EBUS-TBNA Xpert, acid-fast bacilli, culture, and peripheral blood QuantiFERON-TB Gold (QFT) for differentiating sarcoidosis from tuberculosis intrathoracic lymphadenopathy were analyzed.ResultsA total of 119 patients were included in this analysis. Of those, 83 patients were finally diagnosed with sarcoidosis (N = 50) and tuberculosis (N = 33) intrathoracic lymphadenopathy. Young individuals were more likely to have tuberculosis versus sarcoidosis intrathoracic lymphadenopathy (P = 0.006). Markers of inflammation, including fever, leukocytes, and serum ferritin levels, were significantly higher in tuberculosis versus sarcoidosis intrathoracic lymphadenopathy (P < 0.01). Bilateral lung involvement and symmetry intrathoracic lymphadenopathy were more common in sarcoidosis intrathoracic lymphadenopathy (P < 0.01). In addition, the longest diameter of intrathoracic lymphadenopathy (in cm) was significantly larger in sarcoidosis intrathoracic lymphadenopathy (P = 0.001). However, the largest diameter of lung lesions was significantly shorter (P = 0.005). The sensitivity and specificity values of Xpert and QFT for differentiating these two diseases were 69.70% and 100%, and 96.43% and 91.84%, respectively.ConclusionXpert MTB/RIF is recommended for the diagnosis of tuberculosis intrathoracic lymphadenopathy using EBUS-TBNA samples. A negative QFT suggests the exclusion of the diagnosis of tuberculosis intrathoracic lymphadenopathy.

Potential zoonotic agents in sea turtles: Chlamydia species and Listeria monocytogenes

Abstract Background Sea turtles are well recognized sentinels of marine environment as well as carrier of pathogens and contaminants. Chlamydial species have been described in reptiles, but scarce data regarding sea turtles are available in literature (Pace et al., 2022). Hitherto, only one case of listeriosis has been described in marine reptiles (Di Renzo et al., 2022). This study reports the detection of Chlamydia species and Listeria monocytogenes in loggerhead sea turtles (Caretta caretta), suggesting the role of these animals as carriers of potential zoonotic agents. Methods In 2022, a total of 11 sea turtles found stranded along Emilia-Romagna coast, Northwestern Adriatic Sea, were subjected to post mortem investigation. Cloacal swabs were collected from 10 of the investigated animals and screened for Chlamydiaceae family by qPCR targeting 23S rRNA gene, followed by confirmation via 16S rRNA fragment sequencing. For positive samples, Chlamydia species identification was performed by species-specific qPCR for C. abortus, C. pneumoniae, C. pecorum, C. psittaci. One subject showed internal organs disseminated with multiple nodular lesions that were sampled for histopathology analyses, alongside microbiological examination. The cultured isolates were identified by MALDI-TOF (MALDI Biotyper; Bruker Daltonics Inc). Results In six out of 10 cloacal swabs Chlamydiaceae DNA was demonstrated by qPCR and confirmed by sequencing of 16S rRNA, but species identification was not achieved. In the turtle with nodular lesions, histopathology revealed the presence of granulomas: the Ziehl-Neelsen stain was negative for acid-fast organisms. L. monocytogenes was isolated from heart and liver and listeriosis was diagnosed. Conclusions The results highlight how sea turtles can be carriers, symptomatic or not, of pathogens relevant for public health. Given the zoonotic potential of these microorganisms, particular precautions are recommended especially for professionals handling these animals. Key messages • Sea turtles can play an active role as carriers of possibly pathogenetic microorganisms. • Further studies of molecular identification of Chlamydia spp. from sea turtles are needed in atypical strains.

Genomic, phenotypic and demographic characterization of Mycobacterium tuberculosis in Israel in 2021.

According to World Health Organization WHO, Tuberculosis (TB) is the second cause of death from infectious disease worldwide. During 2021, 10.6 million people were infected with TB, and 1.6 million people died. TB is caused by pathogens belonging to the Mycobacterium tuberculosis complex (MTBC), mainly by Mycobacterium tuberculosis (M.tb). Members of this complex are acid-fast bacilli, which can cause intrapulmonary and extra pulmonary TB, and can be divided into various lineages, based on genomic markers. The main public health threat comes from drug resistant M.tb strains, which are responsible for about 25% of TB death and treatment failure worldwide. Treating drug resistant TB patients significantly raises the costs of TB treatment. This study provides an overview of the demographic and drug susceptibility characteristics of newly diagnosed TB patients in Israel in 2021. The State of Israel has a very low level of TB endemicity and is at a pre-elimination phase. Notably, only 11.7% of the newly diagnosed TB patients were born in Israel. In this report, of the 154 new laboratory-confirmed TB patients, 66.7% had pulmonary TB, while 16% had extrapulmonary TB. Males accounted for 52% of the patients, with the most prevalent age group being 21-40. Most patients were citizens of Israel (53.9%), while 37.7% had no Israeli citizenship. Among non-citizens, there was a predominance of males and patients aged 21-40. The susceptibility profile showed a high resistance rate to streptomycin (18.2%) and to a lower extent to isoniazid (13.6%), pyrazinamide (8.4%), rifampicin (7.8%), and ethambutol (3.2%). Only 2 cases of XDR-TB and 10 MDR-TB strains were detected in Israel in 2021, with both XDR strains and 5 out of 10 MDR strains belonging to the Beijing lineage. Most of Beijing isolates were resistant to at least one tested drug. Genomic sequencing of 134 out of 156 strains and bioinformatics analysis using the MTBseq program and WHO mutation catalogue shows a good match with only 9 discrepancies between phenotypic and genotypic susceptibility profiles in first line drugs. The most common lineage is Delhi-Cas (23%) followed by the Beijing lineage (17%). Most patients from the Delhi-Cas lineage were born in Africa, while patients with Beijing isolates were born in different countries. Minimum spanning tree analysis identified 15 clusters. The study highlights the need for ongoing surveillance of TB using molecular and phenotypic tools to further decreasing the spreading level of the disease and develop effective treatment strategies.

An Interesting Case Report on Calcaneal Tuberculosis as a Rare Presentation of Disseminated Tuberculosis

Despite the high prevalence rate of tuberculosis infection in Malaysia, calcaneal tuberculosis (TB) is rare. In this article, we present a case of a 53-year-old Malay female who initially presented with left calcaneal swelling for 3 months. Surgical drainage was performed and affected calcaneal was biopsied for histological examination which findings reported as consistent with tuberculosis infection. Further history revealed concomitant respiratory symptoms with the diagnosis of disseminated TB is supported by positive Mantoux test, detection of Acid-Fast bacilli in sputum and CT imaging showing lung and vertebral involvement. Anti-tuberculosis medication is the first line of treatment in calcaneal TB and surgery is usually reserved for patient with severe, intractable disease. Bangladesh Journal of Infectious Diseases, June 2023;10(1):52-55

Comparison of 2 PCR assays on environmental samples cultured for Mycobacterium avium subsp. paratuberculosis.

Mycobacterium avium subsp. paratuberculosis (MAP) is the causal agent of paratuberculosis, a chronic, contagious, and incurable enteric disease of ruminants. An in-house IS900 PCR assay validated for MAP detection in sheep has been shown to have a higher sensitivity than a commercial PCR and fecal culture. We have now compared the performance of this in-house IS900 PCR assay with a commercial ISMap02 PCR assay for the detection of MAP DNA in bovine dairy farm environmental samples. We purposefully selected 30 culture-positive, 62 culture-negative, and 62 non-interpretable environmental samples. We applied the IS900 PCR assay directly to the frozen inoculum of these samples. Inocula were incubated in an automated system, and growth was confirmed by an acid-fast bacilli stain and the IS900 PCR assay. Among culture-positive samples before incubation, the IS900 PCR assay yielded significantly more positive results than the ISMap02 PCR assay; however, among culture-negative samples, the IS900 PCR assay yielded positive results both before and after incubation. The ISMap02 PCR assay did not flag positively among the culture-negative samples either before or after incubation. The IS900 PCR assay is a sensitive method that can be used to detect MAP DNA in environmental samples before incubation. The ISMap02 PCR assay is a specific method used to detect MAP DNA in environmental samples both before and after incubation.

Risk factors for microbiological persistence after 6 months of treatment for Mycobacterium intracellulare and its impact on the drug-resistance profile.

Patients with Mycobacterium intracellulare pulmonary disease are more likely to experience poor treatment outcomes if they have been observed with microbiological persistence after 6 months of treatment. This study aims to identify the risk factors for microbiological persistence and describe the changes in the minimum inhibitory concentration (MIC) during antimycobacterial treatment. This retrospective case-control study enrolled patients diagnosed with M. intracellulare pulmonary disease between April 2017 and September 2021 at Shanghai Pulmonary Hospital. Patients with positive cultures after 6 months of treatment (positive group) were matched by age and sex in a 1:1 ratio to patients with negative conversion (negative group). Totally, 46 pairs of patients were analyzed. Risk factors for microbiological persistence at month 6 were smoking, previous tuberculosis treatment, chronic lung diseases, a positive baseline acid-fast bacilli smear, and adverse drug reactions; the risk was reduced by a regimen containing ethambutol, ≥3 effective drugs, and a higher pre-treatment absolute lymphocyte count. Regarding the drug-resistance profile, the negative group had a higher proportion of susceptibility to clarithromycin (100.0% vs 84.8%, P = 0.012). Most isolates were susceptible or intermediate to amikacin in both groups (93.5% and 84.8%, respectively). Nine patients (16.4%, 9/55) had a change in the drug-resistance profile, including four who changed from clarithromycin susceptible to clarithromycin resistant, and the other three reversed. Two pairs of isolates had a change in resistance to amikacin. In conclusion, risk factors for microbiological persistence were identified, and the change in MIC values during antimycobacterial treatment indicated the need for monitoring to enable timely adjustment of the regimen.IMPORTANCENontuberculous mycobacteria pulmonary disease (NTM-PD) has been recognized as an important public health issue because of its increasing incidence globally, low cure rate, and high recurrence rate. NTM-PD has innate resistance to many first-line anti-tuberculous drugs, which limits the treatment options. Mycobacterium intracellulare is reportedly the most important pathogenic NTM and accounts for the highest proportion of NTM-PD in China. A previous study suggested that poor microbiological response after 6 months of treatment is predictive of treatment failure. The present study investigated the risk factors associated with persistent positive sputum cultures by treatment month 6 in patients with M. intracellulare pulmonary disease and the variation in minimum inhibitory concentration patterns in clinical settings. This information might help to identify patients at higher risk of treatment failure and enable the timely provision of necessary interventions.

Mastitis granulomatosa no caseificante: revisión retrospectiva de 61 casos

ObjectiveTo determine the clinical characteristics, diagnosis and treatment options of non-caseating granulomatous mastitis. MethodsThe present study is descriptive, cross-sectional, retrospective and non-experimental of 61 patients treated at the Hospital Belen of Trujillo, from January 2018 to December 2022. The inclusion criterion was that they have a histopathological diagnosis of granulomatous mastitis without caseification Acid-Fast Bacilli negative. Results93.4% affected women of reproductive age (age average 33 ± 7 years). Parity, having finishing breastfeeding and the use of contraceptives were associated in a statistically significant way with matitis (p ≤ 0.05). It mostly affected the left breast. The tumor varied between 3 and 11 cm with an average size of 5 ± 2 cm. In 49.2%, the tumor was accompanied by one or more fistulas. 38.5% used hormonal contraceptives. The culture of 25 biopsied breast tissues was negative. The ultrasound study was categorized in 91.8% as BIRADS 2 and 3. 67.2% improved with anti-tuberculosis treatment even though there was no evidence of positive AFB. 32.8% improved with diverse treatment, with antibiotics and without antibiotics. ConclusionsThis type of mastitis occurs in the reproductive stage of the woman, but after the lactation period. Hormonal contraceptives could predispose to this condition. Its management is variable, it can be done with anti-tuberculosis drugs, common antibiotics and in extreme cases surgical resection.

Anaplastic Thyroid Carcinoma Mimicking Cervical Tuberculosis: A Case Report.

Anaplastic thyroid carcinoma is a rare and aggressive form of thyroid cancer that has a poor prognosis and a high mortality rate. It is characterized by rapid growth and invasion of nearby tissues. It typically presents as a rapidly growing goiter or nodule that is firm to the touch and firmly attached to the underlying structures. Case reports of unusual presentations of anaplastic thyroid carcinoma have been reported. The presentation of anaplastic thyroid carcinoma mimicking cervical tuberculosis is very unusual. We reported a case of a 65-year-old patient who had a left cervical swelling that had been evolving for 4 months, causing dysphagia. Initial imaging showed a necrotic mass in the left lobe of the thyroid, communicating with a second necrotic mass in the subcutaneous tissue that was fistulized to the skin and suggesting cervical tuberculosis. The mass was incised with pus and whitish material resembling caseous tuberculosis was discharged. Acid-fast bacilli (AFB) Polymerase chain reaction (PCR) was negative and biopsy revealed a nonspecific granulomatous lesion. Due to the growth of the mass and the presence of a permeation nodule, a second biopsy was performed, revealing anaplastic thyroid carcinoma. The patient was referred for radiochemotherapy due to tumor inoperability.

Tension pneumothorax mimicking giant bullae associated with tuberculosis: a case report

Cough, dyspnea, and chest pain are some of the clinical signs of giant bullae, while in some cases it may be asymptomatic. A pneumothorax can be difficult to identify from giant bullae. A middle-aged patient who had a persistent cough and increasing dyspnea with exertion arrived to the emergency room (ED). A right tension pneumothorax was anticipated based on clinical examination findings, however chest radiography, followed by a contrast-enhanced CT (CECT) scan of the chest showed that the right and left hemithorax were both occupied with giant bullae. Pulmonary tuberculosis (PTB) was diagnosed with sputum for acid-fast bacilli analysis and cartridge based nucleic acid amplification testing (CBNAAT). He was started on antituberculous therapy (ATT) and bullectomy was scheduled for TB-related giant pulmonary bullae.

A rare case of actinomycosis in routine fnac of the face in a tertiary care center in Central India

Actinomycosis is a chronic suppurative bacterial infection. It is caused by gram-positive, non-acid fast, filamentous, anaerobic to microaerophilic bacilli. Actinomycosis on the root of the nose is a rare entity. We report a case of 38 years old male who presented with swelling over the root of the nose since birth. Mucoid material was aspirated. Microscopic examination reveals a filamentous structured colony and crystal against the granular proteinaceous background. Features suggest benign cystic lesion and secondary actinomycosis infection, negative with an acid-fast bacilli stain consistent with Actinomyces species. As stated in most of the literature, mainly males are affected by this condition. Very little information is available on the use of fine-needle aspiration cytology (FNAC) to diagnose these lesions. We are reporting a case of an actinomycotic lesion that was reliably diagnosed with FNAC. So, we emphasized here that FNAC is aninexpensive, rapid, and simple outpatient procedure that helps in the rapid diagnosis of Actinomycosis.

Localization and phenotyping of tuberculosis bacteria using a combination of deep learning and SVMs

Successful treatment of pulmonary tuberculosis (TB) depends on early diagnosis and careful monitoring of treatment response. Identification of acid-fast bacilli by fluorescence microscopy of sputum smears is a common tool for both tasks. Microscopy-based analysis of the intracellular lipid content and dimensions of individual Mycobacterium tuberculosis (Mtb) cells also describe phenotypic changes which may improve our biological understanding of antibiotic therapy for TB. However, fluorescence microscopy is a challenging, time-consuming and subjective procedure. In this work, we automate examination of fields of view (FOVs) from microscopy images to determine the lipid content and dimensions (length and width) of Mtb cells. We introduce an adapted variation of the UNet model to efficiently localising bacteria within FOVs stained by two fluorescence dyes; auramine O to identify Mtb and LipidTox Red to identify intracellular lipids. Thereafter, we propose a feature extractor in conjunction with feature descriptors to extract a representation into a support vector multi-regressor and estimate the length and width of each bacterium. Using a real-world data corpus from Tanzania, the proposed method i) outperformed previous methods for bacterial detection with a 8% improvement (Dice coefficient) and ii) estimated the cell length and width with a root mean square error of less than 0.01%. Our network can be used to examine phenotypic characteristics of Mtb cells visualised by fluorescence microscopy, improving consistency and time efficiency of this procedure compared to manual methods.

Value of Acid-Fast Bacilli and Fungal Cultures in Foot and Ankle Surgery in a US Hospital System.

Acid-fast bacilli(AFB) and fungi are generally slow-growing, difficult to culture, and rarely the cause of infection. The goal of this study was to evaluate the value of routinely obtaining AFB and fungal cultures in foot and ankle surgery at a US hospital. A retrospective review was conducted to determine the number of positive AFB and fungal cultures out of the total number of foot and ankle samples tested. Between 2014 and 2019, patients who underwent surgery for a foot and ankle infection for soft tissue infection, septic arthritis, infectious postoperative complications were identified. Charts were reviewed to identify the results of the microbiological tests performed. To determine the value of running AFB and fungal cultures, the costs of each were provided by the microbiology lab at our institution. Of the 322 patient charts reviewed, there were 434 AFB and 525 fungal cultures performed. None of these cultures were indicated to be positive for AFB (0%), and 22 (4.19%) were positive for fungi. The total labor and material costs were calculated to be $38 767. The AFB cultures cost $23 967, the positive fungal cultures cost $2371, and the negative fungal cultures cost $36 395.36. This 322-case series of surgically managed foot and ankle infections showed 0% and 4.1% positivity rates of AFB and fungal cultures, respectively. Additionally, only 20% of cases with positive cultures were identified as pathologic requiring antifungal treatment. Further analysis is needed to determine best practices for obtaining vs declining to culture for AFB or fungal species, including assessing patient outcomes in the series of culture-positive(fungal-only) cases. Our results suggest that in our clinical setting of a US hospital system, routine fungal and AFB cultures may not be necessary but should be considered for chronic/recalcitrant infections, immunocompromised patients, and those with high surgeon suspicion. Level IV, case series.

Co-infection with Neisseria mucosa in a patient with tuberculous otitis media

Tuberculous otitis media (TOM) is a rare manifestation caused by Mycobacterium tuberculosis with low incidence rates among extrapulmonary tuberculosis cases. Diagnosis is often delayed because of the presence of several clinical manifestations and the high prevalence of secondary bacterial infections. Few reports have attributed secondary bacterial infections in patients with TOM to commensal Neisseria. Thus, understanding the pathogenic mechanisms and clinical features of commensal Neisseria is important, considering its recent presentation as an infection-causing pathogen. Neisseria mucosa is a commensal inhabitant in humans and is generally considered non-pathogenic but can cause infection in rare cases. Here, we report an atypical secondary infection caused by Neisseria mucosa in an 81-year-old woman with TOM being treated for pulmonary tuberculosis. Direct purulent otorrhea smear microscopy revealed no acid-fast bacilli using Ziehl-Neelsen staining, whereas the phagocytosis of gram-negative cocci by white blood cells was confirmed using Gram staining. Otorrhea culture revealed the growth of N. mucosa. Subsequently, M. tuberculosis infection in the otorrhea was identified using a culture-based method. Vigilance is critical for the early detection of TOM to prevent further complications. This report raises awareness regarding TOM and provides insight into the pathogenicity of N. mucosa in otitis media.

Pathogenesis of an experimental mycobacteriosis in an apple snail.

In this work, we aimed at investigating cell and tissue responses of the apple snail Pomacea canaliculata, following the inoculation of the zoonotic pathogen Mycobacterium marinum. Different doses were tested (10, 20, 65, and 100 M CFU) and the mortality rate was negligible. The histopathogenesis was followed at 4, 9, and 28 days after inoculation. Overt histopathological lesions were consistently observed after the two largest doses only. In the lung, marked hemocyte aggregations, including intravascular nodule formation, were observed within the large blood veins that run along the floor and roof of this organ. Hemocyte aggregations were found occluding many of the radial sinuses supplying the respiratory lamina. Acid-fast bacilli were contained in the different hemocyte aggregations. In addition, hemocytes were observed infiltrating the storage tissue, which makes up most of the lung wall, and the connective tissue of the mantle edge. Additionally, signs of degradation in the storage tissue were observed in the lung wall on day 28. In the kidney, nodules were formed associated with the constitutive hemocyte islets and with the subpallial hemocoelic space, in whose hemocytes the acid-fast structures were found. Electron microscopy analysis revealed the presence of bacteria-containing phagosomes within hemocytes located in the surface zone of the islets. Additionally, electron-dense spheroidal structures, which are likely remnants of digested mycobacteria, were observed in close proximity to the hemocytes' nuclei. The size attained by the hemocyte nodules varied during the observation period, but there was no clear dependence on dose or time after inoculation. Nodules were also formed subpallially. Some of these nodules showed 2-3 layers with different cellular composition, suggesting they may also form through successive waves of circulating cells reaching them. Nodular cores, including those formed intravascularly in the lung, would exhibit signs of hemocyte dedifferentiation, possibly proliferation, and death. Hemocyte congestion was observed in the hemocoelic spaces surrounding the pallial ends of the renal crypts, and the renal crypts themselves showed de-epithelization, particularly on day 28. The diverse cellular responses of P. canaliculata to M. marinum inoculation and the high resilience of this snail to the pathogen make it a suitable species for studying mycobacterial infections and their effects on cellular and physiological processes.