Canine Leproid Granuloma (CLG) Caused by Mycobacterial Species Closely Related to Members of Mycobacterium Simiae Complex in a Dog in Brazil.

This report describes the clinical features and molecular diagnosis of a case of canine leproid granuloma (CLG) caused by mycobacterial strains of the Mycobacterium simiae complex in Brazil. A 12-year-old non-neutered male Labrador Retriever dog was presented with a 2-week history of progressive painless cutaneous lesions. Ulcerated nodules with hematic crusts were observed on the dorsal surface of the right and left pinna and on the metacarpal, metatarsal, and digits. Complete blood count, serum biochemistry, aspiration cytology of cutaneous lesions, biopsy for histopathological evaluation, culture for aerobic and anaerobic bacteria, polymerase chain reaction and DNA sequencing to identify mycobacterial species were performed. According to the clinical and histopathological findings, a diagnosis of CLG was established. Despite the negative result of the bacterial culture, mycobacterial identification was made by sequencing the hsp65 gene. Our findings highlight that mycobacterial species closely related to members of the M simiae clade can be causative agents of CLG.

Antimicrobial Activity of Neutrophils Against Mycobacteria.

The mycobacterium genus contains a broad range of species, including the human pathogens M. tuberculosis and M. leprae. These bacteria are best known for their residence inside host cells. Neutrophils are frequently observed at sites of mycobacterial infection, but their role in clearance is not well understood. In this review, we discuss how neutrophils attempt to control mycobacterial infections, either through the ingestion of bacteria into intracellular phagosomes, or the release of neutrophil extracellular traps (NETs). Despite their powerful antimicrobial activity, including the production of reactive oxidants such as hypochlorous acid, neutrophils appear ineffective in killing pathogenic mycobacteria. We explore mycobacterial resistance mechanisms, and how thwarting neutrophil action exacerbates disease pathology. A better understanding of how mycobacteria protect themselves from neutrophils will aid the development of novel strategies that facilitate bacterial clearance and limit host tissue damage.

Mycobacterial Infections in the Hand and Wrist.

Mycobacterial hand infections are uncommon. These infections have an indolent course and are marked by variable and nonspecific presentations, often leading to diagnostic and treatment delays. The pathogens involved in mycobacterial hand infections include Mycobacterium tuberculosis complex, atypical mycobacteria, and M leprae. Initial treatment involves a combination of long-term antibiotics and surgical débridement to cure the infection. Reconstructive procedures aid in restoring hand function lost secondary to the disease.

Long-term ulcerations caused by Mycobacterium lepromatosis.

Patients with leprosy rarely present ulcerated lesions that can appear during reactional states like Lucio's phenomenon (LP), as in our case. LP is a rare complication of multibacillary leprosy due to massive bacilli invasion of endothelial cells causing a thrombotic syndrome. The initial macular lesion is purpuric followed by multiple infiltrated papules and nodules, some of them ulcerated, associated to loss of sensation on lower limbs. The importance of recognizing ulcers as a specific cutaneous manifestation of leprosy allows early diagnosis and treatment, and therefore avoiding the development of disabilities and persistence of illness. Infection by Mycobacterium lepromatosis is associated with LP and it should be especially sought in patients from endemic areas.

Cutaneous Mycobacterial Infections.

Humans encounter mycobacterial species due to their ubiquity in different environmental niches. In many individuals, pathogenic mycobacterial species may breach our first-line barrier defenses of the innate immune system and modulate the activation of phagocytes to cause disease of the respiratory tract or the skin and soft tissues, sometimes resulting in disseminated infection. Cutaneous mycobacterial infections may cause a wide range of clinical manifestations, which are divided into four main disease categories: (i) cutaneous manifestations of Mycobacterium tuberculosis infection, (ii) Buruli ulcer caused by Mycobacterium ulcerans and other related slowly growing mycobacteria, (iii) leprosy caused by Mycobacterium leprae and Mycobacterium lepromatosis, and (iv) cutaneous infections caused by rapidly growing mycobacteria. Clinically, cutaneous mycobacterial infections present with widely different clinical presentations, including cellulitis, nonhealing ulcers, subacute or chronic nodular lesions, abscesses, superficial lymphadenitis, verrucous lesions, and other types of findings. Mycobacterial infections of the skin and subcutaneous tissue are associated with important stigma, deformity, and disability. Geography-based environmental exposures influence the epidemiology of cutaneous mycobacterial infections. Cutaneous tuberculosis exhibits different clinical phenotypes acquired through different routes, including via extrinsic inoculation of the tuberculous bacilli and dissemination to the skin from other sites, or represents hypersensitivity reactions to M. tuberculosis infection. In many settings, leprosy remains an important cause of neurological impairment, deformity, limb loss, and stigma. Mycobacterium lepromatosis, a mycobacterial species related to M. leprae, is linked to diffuse lepromatous leprosy of Lucio and Latapí. Mycobacterium ulcerans produces a mycolactone toxin that leads to subcutaneous tissue destruction and immunosuppression, resulting in deep ulcerations that often produce substantial disfigurement and disability. Mycobacterium marinum, a close relative of M. ulcerans, is an important cause of cutaneous sporotrichoid nodular lymphangitic lesions. Among patients with advanced immunosuppression, Mycobacterium kansasii, the Mycobacterium avium-intracellulare complex, and Mycobacterium haemophilum may cause cutaneous or disseminated disease. Rapidly growing mycobacteria, including the Mycobacterium abscessus group, Mycobacterium chelonei, and Mycobacterium fortuitum, are increasingly recognized pathogens in cutaneous infections associated particularly with plastic surgery and cosmetic procedures. Skin biopsies of cutaneous lesions to identify acid-fast staining bacilli and cultures represent the cornerstone of diagnosis. Additionally, histopathological evaluation of skin biopsy specimens may be useful in identifying leprosy, Buruli ulcer, and cutaneous tuberculosis. Molecular assays are useful in some cases. The treatment for cutaneous mycobacterial infections depends on the specific pathogen and therefore requires a careful consideration of antimicrobial choices based on official treatment guidelines.

Lesiones cutáneas hipocrómicas en paciente natural de Brasil / Hypochromic skin lesions in Brazilian patient

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[Feline leprosy in a 5-month-old male cat in Germany]. / Feline Lepra bei einem 5 Monate alten Kater in Deutschland.

A 5-month-old, male, 4 kg European shorthair cat presented with ulcera ted cutaneous nodules in many areas over its entire body. The serological results for feline immunodeficiency virus and the feline leukaemia virus were negative. Following detection of acid-proof bacilli in histological examination of three skin biopsies, the diagnosis of mycobacteriosis of the skin was made. Polymerase chain reaction revealed the presence of Mycobacteriumlepraemurium. After surgical excision of all cutaneous nodules and a 14.5-week antibiotic therapy with Rifampicin and Clarithromycin, the cat was classified as being cured. During the observation period of 1 year after the end of the therapy, no relapse occurred.

Mycobacterial disease in patients with chronic granulomatous disease: A retrospective analysis of 71 cases.

BACKGROUND: Chronic granulomatous disease (CGD) is a rare primary immunodeficiency caused by inborn errors of the phagocyte nicotinamide adenine dinucleotide phosphate oxidase complex. From the first year of life onward, most affected patients display multiple, severe, and recurrent infections caused by bacteria and fungi. Mycobacterial infections have also been reported in some patients. OBJECTIVE: Our objective was to assess the effect of mycobacterial disease in patients with CGD. METHODS: We analyzed retrospectively the clinical features of mycobacterial disease in 71 patients with CGD. Tuberculosis and BCG disease were diagnosed on the basis of microbiological, pathological, and/or clinical criteria. RESULTS: Thirty-one (44%) patients had tuberculosis, and 53 (75%) presented with adverse effects of BCG vaccination; 13 (18%) had both tuberculosis and BCG infections. None of these patients displayed clinical disease caused by environmental mycobacteria, Mycobacterium leprae, or Mycobacterium ulcerans. Most patients (76%) also had other pyogenic and fungal infections, but 24% presented solely with mycobacterial disease. Most patients presented a single localized episode of mycobacterial disease (37%), but recurrence (18%), disseminated disease (27%), and even death (18%) were also observed. One common feature in these patients was an early age at presentation for BCG disease. Mycobacterial disease was the first clinical manifestation of CGD in 60% of these patients. CONCLUSION: Mycobacterial disease is relatively common in patients with CGD living in countries in which tuberculosis is endemic, BCG vaccine is mandatory, or both. Adverse reactions to BCG and severe forms of tuberculosis should lead to a suspicion of CGD. BCG vaccine is contraindicated in patients with CGD.

Mycobacterium haemophilum infection with prominent facial manifestation mimicking leprosy.

Mycobacterium haemophilum is a slow-growing non-tuberculous mycobacterium that is rarely known to cause human skin infection, particularly in immunocompromised patients. We recently experienced a 69-year-old Japanese woman with this infection who had been under immunosuppressive treatment for recalcitrant rheumatoid arthritis. The patient showed disseminated erythematous plaques and subcutaneous nodules on the face and extremities, and interestingly, the face manifested with a striking "facies leontina" appearance. Biopsy revealed abscess and granulomatous dermatitis with the involvement of peripheral nerve bundles and the presence of innumerable acid-fast bacilli, thus necessitating differentiation from lepromatous leprosy. M. haemophilum was identified by molecular characterization as well as by successful culture with iron supplements. Although drug susceptibility testing indicated responsiveness to multiple antibiotics administrated simultaneously for the treatment, it took over 6 months to achieve significant improvement, and we also employed concurrent oral potassium iodide administration and repeated surgical excision. This case highlights the importance of continuous combination therapy for successful outcome in this rare infection. Furthermore, application of potassium iodide for mycobacterial infection warrants further evaluation by accumulating more cases.

Evaluation of a low-density hydrogel microarray technique for mycobacterial species identification.

In addition to the obligatory pathogenic species of the Mycobacterium tuberculosis complex and Mycobacterium leprae, the genus Mycobacterium also includes conditionally pathogenic species that in rare cases can lead to the development of nontuberculous mycobacterial diseases. Because tuberculosis and mycobacteriosis have similar clinical signs, the accurate identification of the causative agent in a clinical microbiology laboratory is important for diagnostic verification and appropriate treatment. This report describes a low-density hydrogel-based microarray containing oligonucleotide probes based on the species-specific sequences of the gyrB gene fragment for mycobacterial species identification. The procedure included the amplification of a 352-nucleotide fragment of the gene and its hybridization on a microarray. The triple-species-specific probe design and the algorithm for hybridization profile recognition based on the calculation of Pearson correlation coefficients, followed by the construction of a profile database, allowed for the reliable and accurate identification of mycobacterial species, including mixed-DNA samples. The assay was used to evaluate 543 clinical isolates from two regions of Russia, demonstrating its ability to detect 35 mycobacterial species, with 99.8% sensitivity and 100% specificity when using gyrB, 16S, and internal transcribed spacer (ITS) fragment sequencing as the standard. The testing of clinical samples showed that the sensitivity of the assay was 89% to 95% for smear-positive samples and 36% for smear-negative samples. The large number of identified species, the high level of sensitivity, the ability to detect mycobacteria in clinical samples, and the up-to-date profile database make the assay suitable for use in routine laboratory practice.

Feline mycobacterial infections.

Mycobacteria of feline importance include (1) obligate pathogens (tuberculosis), (2) mycobacteria that are difficult to grow, so the environmental niche is unknown (feline leprosy syndrome), and (3) facultative pathogenic opportunistic saprophytes (non-tuberculous mycobacteriosis). Most cats present with cutaneous disease, although some have systemic involvement. Diagnosis is challenging because there are no pathognomonic histopathological changes and many mycobacteria fail to culture, so molecular diagnostics are required. Treatment can involve extended multidrug therapy and prognosis is variable. This article reviews the microbiology, clinical diagnosis, management and prognosis of feline mycobacterial infections.

Mycobacterium leprae and Mycobacterium haemophilum co-infection in an iatrogenically immunosuppressed patient.

We present the case of a native Texan who was diagnosed with tuberculoid leprosy and later developed a cutaneous infection with M. haemophilum following iatrogenic immunosuppression. To our knowledge, there are no such reports of M. haemophilum and M. leprae infection occurring simultaneously in the same host.

[Nontuberculous mycobacterial infections of the lung]. / Atypische Mykobakteriose der Lunge.

Nontuberculous mycobacterium (NTM) species are mycobacterial species other than those belonging to the Mycobacterium tuberculosis complex and M. leprae. NTM are generally free-living organisms that are ubiquitous in the environment. Pulmonary disease, especially in older persons with and without underlying lung disease, is caused primarily by M. avium complex (MAC) and M. kansasii. The symptoms and signs of MAC lung disease are variable and not specific, but include cough, malaise, weakness, dyspnoea, chest discomfort and occasionally hemoptoe. Two major clinical presentations include disease in those with underlying lung disease, primarily white, middle-aged or elderly men - often alcoholics and/or smokers with underlying chronic obstructive lung disease, patients in whom MAC develops in areas of prior bronchiectasis, and patients with cystic fibrosis; and those without known underlying lung disease, including non-smoking women over age 50 who have interstitial patterns on chest radiography. M. kansasii infections are endemic in cities with infected tap water. Symptoms of the M. kansasii lung disease resemble to tuberculosis. M. abszessus is the most pathogenic rapid growing Mycobacterium which causes pulmonary infection. The American Thoracic Society and Infectious Disease Society of America's diagnostic criteria for nontuberculous mycobacterial pulmonary infections include both imaging studies consistent with pulmonary disease and recurrent isolation of mycobacteria from sputum or isolated from at least one bronchial wash in a symptomatic patient. For treatment of MAC lung disease we recommend depending on severity and susceptibility testing a three to four drug treatment with a macrolide, rifampicin and ethambutol and for M. kansasii a treatment with Isoniazid, rifampicin and ethambutol. Surgical management only plays a role in rare and special cases. Treatment should be continued until sputum cultures are consecutively negative for at least one year.

Lateral flow assay for simultaneous detection of cellular- and humoral immune responses.

OBJECTIVE: The development of a cytokine detection assay suitable for detection of multiple biomarkers for improved diagnosis of mycobacterial diseases. DESIGN AND METHODS: A lateral flow (LF) assay to detect IL-10 was developed utilizing the up-converting phosphor (UCP) reporter-technology. The assay was evaluated using blood samples of leprosy patients. Multiplex applications were explored targeting: 1) IL-10 and IFN-γ in assay buffer; 2) IL-10 and anti-phenolic glycolipid (PGL-I) antibodies in serum from leprosy patients. RESULTS: Detection of IL-10 below the targeted level of 100pg/mL in serum was shown. Comparison with ELISA showed a quantitative correlation with R(2) value of 0.92. Multiplexing of cytokines and simultaneous detection of cytokine and antibody was demonstrated. CONCLUSIONS: The UCP-LF IL-10 assay is a user-friendly, rapid alternative for IL-10 ELISAs, suitable for multiplex detection of different cytokines and can be merged with antibody-detection assays to simultaneously detect cellular- and humoral immunity.

[Lung mycobacteriosis--clinical presentation, diagnostics and treatment]. / Mikobakteriozy pluc--obraz kliniczny, diagnostyka i leczenie.

Nontuberculous mycobacteria (NTM) are a group of bacteria that may cause human disease mycobacteriosis, but do not cause tuberculosis or leprosy. NTM are acquired through environmental exposure to water, aerosols, soil, dust and are transferred to humans through inhalation, ingestion, and skin lesions, due to injuries, surgical procedures, or intravenous catheters. People with suppressed immune response, with pre-existing lung damage in the course of various lung diseases are most likely to be affected. There is no evidence of person-to-person spread of these diseases. A variety of manifestations of NTM infection have been described, but the lungs remain the most commonly involved site. Molecular methods allow the quicker differentiation of NTM from TB isolates and help to identify new NTM species. The purpose of this article is to review the common clinical manifestations of NTM lung disease, the conditions associated with NTM lung disease, diagnostic criteria and treatment of the most frequent species of NTM.

[Utility of molecular biology in the microbiological diagnosis of mycobacterial infections]. / Utilidad de la biología molecular en el diagnóstico microbiológico de las infecciones por micobacterias.

Species within the Mycobacterium genus are of major medical interest, since, together with environmental and opportunistic species, there are two species (Mycobacterium tuberculosis and Mycobacterium leprae) that remain an important public health challenge. Despite efforts to control tuberculosis (TB), this disease remains one of the most prominent health problems worldwide. In the last few years, mycobacteriology has experienced major technological advances. Nevertheless, the early diagnosis of mycobacterial infection and, especially of TB, is still based on microscopic examination of properly stained samples. At present, this procedure is still the simplest, fastest and most cost-effective method for preliminary diagnostic guidance. Effective control of TB is based on rapid detection of M. tuberculosis, followed by immediate implementation of the appropriate antituberculosis therapy. Because of the emergence of multidrug resistant strains, the development of rapid diagnostic methods, both for identification of M. tuberculosis and susceptibility testing, has become a pressing need. The availability of molecular epidemiology methods that are easy to implement and standardized and that would allow identification of related cases is of key importance to identify epidemic outbreaks and control the spread of TB. Despite the evident progress in the molecular diagnosis of mycobacterial infections, the available techniques are still inadequate. In this review, we describe the state of the art of the main molecular techniques for direct detection of mycobacteria in clinical samples, their identification, detection of resistance to the most important antituberculosis agents, and molecular epidemiology. In each case, we describe the advantages and limitations of current techniques. In the near future, clinical mycobacteriology will probably evolve to the universal use of genetic techniques for direct diagnosis and detection of resistance. The molecular epidemiology of TB will be performed, in its various applications, by faster and more automated techniques than those currently available.

[Mycobacterium shinshuense and Mycobacterium leprae infections: usefulness of genetical examinations].

Although Mycobacterium shinshuense and M. leprae infections are relatively rare in the fields of dermatology, an early diagnosis is one of the important prognostic factors of these infections. Applications of the genetical examinations such as PCR and 16S rDNA sequencing are helpful in early diagnosis with culture nagative cases. Short target PCR tests are available to detect DNA of M. shinshuense or M. leprae from clinical specimens including formalin fixed-paraffin embedded samples. A partial 16s rDNA sequencing is functional with enough intact bacterial DNA. A similarity search based on the partial 16S rDNA sequences using RIDOM database is an easy and powerful tool to estimate the species of mycobacteria, however, it is not enough for the identification in some cases. For instance, a clinical isolate of M. shinshuense is clearly discriminated from M. leprae (92.75% sequence identity), however, difficult to be identified from M. marinum and M. ulcerans (99.77% sequence identity). The phylogenetic tree based on 16S rDNA sequences is illustrating that both M. leprae (closely related to M. haemophilum) and M. shinshuense (closely related to M. marinum and M. ulcerans, and also M. tuberculosis) are relatively related species and distantly related to rapidly growing species among 30 species of pathogenic mycobacteria which have been isolated in Japan.