The Experts below are selected from a list of 231 Experts worldwide ranked by ideXlab platform
Allen T Bishop - One of the best experts on this subject based on the ideXlab platform.
-
Atypical Mycobacterium infections of the upper extremity
Journal of Hand Surgery (European Volume), 1994Co-Authors: Scott H Kozin, Allen T BishopAbstract:Thirty-three patients with culture-positive Atypical Mycobacterium infections of the upper extremity underwent surgical debridement and antimicrobial therapy. The causative Atypical organism was M. marinum in 12 cases, M. avium-intracellulare in 7, M. terrae in 4, M. chelonei in 4, M. kansasii in 3, M. fortuitum in 2, and M. ulcerans in 1. The tenosynovium was the most common location of infection (14 patients). The average follow-up period was 36 months. Duration of antimicrobial therapy averaged 10 months. The average delay between onset of symptoms to correct diagnosis was 1 year. There were seven superficial infections; six were caused by M. marinum and one was caused by M. ulcerans. All of these cutaneous infections resolved following incisional or excisional biopsy and pharmacologic therapy. The remaining 26 infections involved the deeper tissues, and M. avium-intracellulare was the most common organism. The immune status of the host was an overwhelming predictor of eventual outcome. In the 15 patients with competent immune systems, resolution occurred in 13. However, in the immunocompromised patient population, only 4 of the 10 had resolution of deep infection at time of the follow-up evaluation.
Ali Akbar Velayati - One of the best experts on this subject based on the ideXlab platform.
-
identification of different subtypes of rapid growing Atypical Mycobacterium from water and soil sources using pcr rflp using hsp65 and rrna 16s 23s genes
The International Journal of Mycobacteriology, 2016Co-Authors: Mohammad Varahram, Parissa Farnia, Shima Saif, Mehran Marashian, Jaladein Ghanavi, Ali Akbar VelayatiAbstract:Abstract Objective/Background Nontuberculosis mycobacteria (NTM) are a diverse group of microorganisms that cause a variety of diseases in humans including skin, respiratory, and gastrointestinal tract infection. Generally, NTM are classified into two categories: rapid ( 7 days). In this study, we aimed to investigate NTM frequency and prevalence in environmental samples. Additionally, we tried to identify various subtypes of isolated rapid growing mycobacteria (RGM). Methods Through a prospective descriptive cross-sectional study, water and soil samples were gathered from four neighboring towns around Tehran, the capital of Iran, at different geographic directions. Every 100 m2 of the studied areas gave one sample containing 6 g of soil in 3–5 cm depth deposited in 50 mL sterile water as sampling media. After digestion and decontamination, DNA from culture-positive specimens (RGM) were extracted using phenol–chloroform methods. Then the molecular identification of species and subspecies were performed using 16s–23s rRNA and hsp65 gene. Results In total, 341 RGM were found, out of which 322 (94.4%) were identified and 20 (5.8%) could not be identified. The most frequent RGM was, Mycobacterium fortuitum (72; 22%), Mycobacterium senegalense (58; 17.7%), Mycobacterium parafortuitum (44; 13.4%) and Mycobacterium conceptionense type 1 (24; 7.2%), and Mycobacterium cheloni type 1 (20; 6.0%). As shown in Table 1 , M. fortuitum had more subtypes (8), and the frequency of subtypes 1 (27.7%), 4 (16.6%), and 5 (13.8%) were higher. Among subtypes of M. senegalense, subtype 1 had a higher frequency (70.4%) in comparison to subtype 2 (29.5%). M. cheloni had just one subtype. Conclusion Our results showed M. fortuitum as the most prominent strain isolated from environmental samples. The frequency was similar in different places, irrespective of climatic variations. Availability of various subtypes of M. fortuitum might indicate a large circulation of this RGM in soil and water of Iranian territory. This high prevalence of M. fortuitum might raise the risk infection, especially in children, immunocompromised patients, diabetics, and cancer cases.
-
Identification of different subtypes of rapid growing Atypical Mycobacterium from water and soil sources: Using PCR-RFLP using hsp65 and rRNA 16s–23s genes
Wolters Kluwer Medknow Publications, 2016Co-Authors: Mohammad Varahram, Parissa Farnia, Shima Saif, Mehran Marashian, Jaladein Ghanavi, Ali Akbar VelayatiAbstract:Objective/Background: Nontuberculosis mycobacteria (NTM) are a diverse group of microorganisms that cause a variety of diseases in humans including skin, respiratory, and gastrointestinal tract infection. Generally, NTM are classified into two categories: rapid (7 days). In this study, we aimed to investigate NTM frequency and prevalence in environmental samples. Additionally, we tried to identify various subtypes of isolated rapid growing mycobacteria (RGM). Methods: Through a prospective descriptive cross-sectional study, water and soil samples were gathered from four neighboring towns around Tehran, the capital of Iran, at different geographic directions. Every 100m2 of the studied areas gave one sample containing 6g of soil in 3–5 cm depth deposited in 50 mL sterile water as sampling media. After digestion and decontamination, DNA from culture-positive specimens (RGM) were extracted using phenol–chloroform methods. Then the molecular identification of species and subspecies were performed using 16s–23s rRNA and hsp65 gene. Results: In total, 341 RGM were found, out of which 322 (94.4%) were identified and 20 (5.8%) could not be identified. The most frequent RGM was, Mycobacterium fortuitum (72; 22%), Mycobacterium senegalense (58; 17.7%), Mycobacterium parafortuitum (44; 13.4%) and Mycobacterium conceptionense type 1 (24; 7.2%), and Mycobacterium cheloni type 1 (20; 6.0%). As shown in [Table 1], M. fortuitum had more subtypes (8), and the frequency of subtypes 1 (27.7%), 4 (16.6%), and 5 (13.8%) were higher. Among subtypes of M. senegalense, subtype 1 had a higher frequency (70.4%) in comparison to subtype 2 (29.5%). M. cheloni had just one subtype.{Table 1} Conclusion: Our results showed M. fortuitum as the most prominent strain isolated from environmental samples. The frequency was similar in different places, irrespective of climatic variations. Availability of various subtypes of M. fortuitum might indicate a large circulation of this RGM in soil and water of Iranian territory. This high prevalence of M. fortuitum might raise the risk infection, especially in children, immunocompromised patients, diabetics, and cancer cases
-
the rapid identification of Atypical Mycobacterium in pulmonary tuberculosis ptb patients evaluation of qub3232 locus using the vntr method
Journal of Advances in Medical and Biomedical Research, 2009Co-Authors: F Heidari, P Farnia, J Noroozi, A Majd, E Tajedin, Ali Akbar VelayatiAbstract:Background and Objective: Identification of Atypical Mycobacterium (Non tuberculosis Mycobacterium NTM) is important because of the worldwide propagation of these organisms. Recently, molecular studies have identified the specific loci for Mycobacterium species by DNA - finger printing methods, but these methods are time-consuming and expensive. In this study, in addition to hsp65 PCR-RFLP method, QUB3232 locus was evaluated for differentiation of Atypical Mycobacterium from Mycobacterium tuberculosis complex. Materials and Methods: This study was performed on 371 pulmonary and non pulmonary specimens separated from patients with the symptoms of pulmonary tuberculosis (PTB). After the isolation and culturing of Mycobacterium strains using the Lowenstein Jensen media, biochemical tests including production of Niacin, Catalase activity, Nitrate reduction, pigment production and growth rate were performed. Drug susceptibility testing was performed by proportional method. DNA extraction was performed by phenol-chloroform method. hsp65 gene was amplified by PCR. Subsequently the amplicons were digested with three restriction enzymes namely AvaII, HphI and HpaII and electrophoresed on 3% agarose gel. QUB3232 locus was also evaluated for differentiation of Atypical Mycobacterium and Mycobacterium tuberculosis complex. Results: Out of 371 isolates, 32 (8.6%) were multi-drug resistant TB (MDR-TB), 184 (49.5%) were susceptible and 155 (42.5%) were non MDR (combined resistance) that 15% of MDR cases and 25% of non MDR cases were non tuberculosis Mycobacterium. Out of 31 slow growing isolates, 58% were M. simiae and 19% were M. kansasii. The sensitivity of QUB3232 locus for differentiation of the Atypical Mycobacterium from Mycobacterium tuberculosis complex was 80%. From the total of 43 NTM samples, 12 (27.9%) were rapid growing and 72% were slow growing. Conclusion: QUB3232 locus has the high discriminative power for differentiation of Atypical Mycobacterium from the Mycobacterium tuberculosis complex, therefore, it can be used as a substitute for PCR-RFLP method.
Scott H Kozin - One of the best experts on this subject based on the ideXlab platform.
-
Atypical Mycobacterium infections of the upper extremity
Journal of Hand Surgery (European Volume), 1994Co-Authors: Scott H Kozin, Allen T BishopAbstract:Thirty-three patients with culture-positive Atypical Mycobacterium infections of the upper extremity underwent surgical debridement and antimicrobial therapy. The causative Atypical organism was M. marinum in 12 cases, M. avium-intracellulare in 7, M. terrae in 4, M. chelonei in 4, M. kansasii in 3, M. fortuitum in 2, and M. ulcerans in 1. The tenosynovium was the most common location of infection (14 patients). The average follow-up period was 36 months. Duration of antimicrobial therapy averaged 10 months. The average delay between onset of symptoms to correct diagnosis was 1 year. There were seven superficial infections; six were caused by M. marinum and one was caused by M. ulcerans. All of these cutaneous infections resolved following incisional or excisional biopsy and pharmacologic therapy. The remaining 26 infections involved the deeper tissues, and M. avium-intracellulare was the most common organism. The immune status of the host was an overwhelming predictor of eventual outcome. In the 15 patients with competent immune systems, resolution occurred in 13. However, in the immunocompromised patient population, only 4 of the 10 had resolution of deep infection at time of the follow-up evaluation.
Patricia M Joyce - One of the best experts on this subject based on the ideXlab platform.
-
lepromatous leprosy in a heart transplant recipient
American Journal of Transplantation, 2003Co-Authors: Kalgi Modi, Mary C Mancini, Patricia M JoyceAbstract:Northern Louisiana is not an area for indigenous cases of leprosy. Limited data are available on the occurrence of leprosy in organ transplant recipients. No cases have been reported in heart transplant recipients. Mr J.R. is a 68-year-old man from Shreveport, Louisiana. He underwent orthotopic heart transplantation in March 1996. He presented in March 2000 with a maculopapular skin rash and intermittent hand swelling for 5 months. He also complained of intermittent burning of his feet for a year. The skin lesions were of two types - a fine red migratory, intermittent maculopapular rash over the upper torso and a raised, larger, violaceaous lesion on his hands. Neurological examination revealed complete loss of protective sensation in the right foot by filamentous test and some loss in the left foot. Punch skin biopsies from his right arm and right chest lesion revealed abundant acid-fast bacilli (AFB). Histopathologic examination revealed perivascular, interstitial and perineural granulomatous inflammation and a large number of AFB organisms within histiocytes. Culture of the skin biopsy specimen was negative for Mycobacterium tuberculosis or Atypical Mycobacterium. Polymerase chain reaction (PCR) performed for Mycobacterium leprae was positive. The patient was treated with a modified regimen consisting of dapsone 100 mg qd, ethionamide 250 mg qd, and minocycline 100 mg qd. His skin rash and neurological symptoms have resolved.
Joe M Viljoen - One of the best experts on this subject based on the ideXlab platform.
-
cutaneous tuberculosis overview and current treatment regimens
Tuberculosis, 2015Co-Authors: Lindi Van Zyl, Jeanetta Du Plessis, Joe M ViljoenAbstract:Tuberculosis is one of the oldest diseases known to humankind and it is currently a worldwide threat with 8-9 million new active disease being reported every year. Among patients with co-infection of the human immunodeficiency virus (HIV), tuberculosis is ultimately responsible for the most deaths. Cutaneous tuberculosis (CTB) is uncommon, comprising 1-1.5% of all extra-pulmonary tuberculosis manifestations, which manifests only in 8.4-13.7% of all tuberculosis cases. A more accurate classification of CTB includes inoculation tuberculosis, tuberculosis from an endogenous source and haematogenous tuberculosis. There is furthermore a definite distinction between true CTB caused by Mycobacterium tuberculosis and CTB caused by Atypical Mycobacterium species. The lesions caused by Mycobacterium species vary from small papules (e.g. primary inoculation tuberculosis) and warty lesions (e.g. tuberculosis verrucosa cutis) to massive ulcers (e.g. Buruli ulcer) and plaques (e.g. lupus vulgaris) that can be highly deformative. Treatment options for CTB are currently limited to conventional oral therapy and occasional surgical intervention in cases that require it. True CTB is treated with a combination of rifampicin, ethambutol, pyrazinamide, isoniazid and streptomycin that is tailored to individual needs. Atypical Mycobacterium infections are mostly resistant to anti-tuberculous drugs and only respond to certain antibiotics. As in the case of pulmonary TB, various and relatively wide-ranging treatment regimens are available, although patient compliance is poor. The development of multi-drug and extremely drug-resistant strains has also threatened treatment outcomes. To date, no topical therapy for CTB has been identified and although conventional therapy has mostly shown positive results, there is a lack of other treatment regimens.
