Investigation and management of an outbreak of multispecies mycobacteriosis in Australian lungfish (Neoceratodus fosteri) including the use of triple antibiotic treatment

Disease due to non-tuberculous mycobacteria (NTM) is common in fish. Current recommendations focus on outbreak management by depopulating entire fish stocks and disinfecting tanks. Treatment is not advocated. Treatment may be appropriate, however, where individual, valuable fish are concerned. ZSL London Zoo managed an outbreak of mycobacteriosis in a valuable group of imported F1 captive-bred Australian lungfish (Neoceratodus fosteri) by depopulation, isolation, extensive testing and daily oral antibiotic treatment. Four species of Mycobacterium (M. marinum, M. fortuitum, M. chelonae and M. peregrinum) were involved in this outbreak, each with unique antibiotic sensitivities. Triple therapy with rifampicin, doxycycline and enrofloxacin for 8 months was the most effective antibiotic combination, resulting in full disease resolution. No side effects were noted and, more than 18 months post-treatment, no recurrence had occurred. This is the first report of mycobacterial disease in lungfish and the first report of a polymycobacterial outbreak in fish involving these four species of Mycobacterium. This report demonstrates the value of extensive isolation and identification. Also, as therapies currently advised in standard texts did not reflect the antibiotic sensitivity of the NTM found in the fish reported here, we recommend that antibiotic treatment should always be based on sensitivity testing.

Study suggests hidden epidemic in CF patients

Dangerous Mycobacterium strains appear to be spreading.

Mycobacterium abscessus Complex Infections in Humans

New treatments, rapid and inexpensive identification methods, and measures to contain nosocomial transmission and outbreaks are urgently needed.

Mycobacterium abscessus complex comprises a group of rapidly growing, multidrug-resistant, nontuberculous mycobacteria that are responsible for a wide spectrum of skin and soft tissue diseases, central nervous system infections, bacteremia, and ocular and other infections. M. abscessus complex is differentiated into 3 subspecies: M. abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. abscessus subsp. bolletii. The 2 major subspecies, M. abscessus subsp. abscessus and M.abscessus subsp. massiliense, have different erm(41) gene patterns. This gene provides intrinsic resistance to macrolides, so the different patterns lead to different treatment outcomes. M. abscessus complex outbreaks associated with cosmetic procedures and nosocomial transmissions are not uncommon. Clarithromycin, amikacin, and cefoxitin are the current antimicrobial drugs of choice for treatment. However, new treatment regimens are urgently needed, as are rapid and inexpensive identification methods and measures to contain nosocomial transmission and outbreaks.

Whole Genome Sequencing of Mycobacterium africanum Strains from Mali Provides Insights into the Mechanisms of Geographic Restriction

Background

Mycobacterium africanum, made up of lineages 5 and 6 within the Mycobacterium tuberculosis complex (MTC), causes up to half of all tuberculosis cases in West Africa, but is rarely found outside of this region. The reasons for this geographical restriction remain unknown. Possible reasons include a geographically restricted animal reservoir, a unique preference for hosts of West African ethnicity, and an inability to compete with other lineages outside of West Africa. These latter two hypotheses could be caused by loss of fitness or altered interactions with the host immune system.

Methodology/Principal Findings

We sequenced 92 MTC clinical isolates from Mali, including two lineage 5 and 24 lineage 6 strains. Our genome sequencing assembly, alignment, phylogeny and average nucleotide identity analyses enabled us to identify features that typify lineages 5 and 6 and made clear that these lineages do not constitute a distinct species within the MTC. We found that in Mali, lineage 6 and lineage 4 strains have similar levels of diversity and evolve drug resistance through similar mechanisms. In the process, we identified a putative novel streptomycin resistance mutation. In addition, we found evidence of person-to-person transmission of lineage 6 isolates and showed that lineage 6 is not enriched for mutations in virulence-associated genes.

Conclusions

This is the largest collection of lineage 5 and 6 whole genome sequences to date, and our assembly and alignment data provide valuable insights into what distinguishes these lineages from other MTC lineages. Lineages 5 and 6 do not appear to be geographically restricted due to an inability to transmit between West African hosts or to an elevated number of mutations in virulence-associated genes. However, lineage-specific mutations, such as mutations in cell wall structure, secretion systems and cofactor biosynthesis, provide alternative mechanisms that may lead to host specificity.

Mycobacterium africanum consists of two lineages, lineages 5 and 6, within the Mycobacterium tuberculosis complex (MTC) that cause human tuberculosis in West Africa, but are found rarely outside of this region. Our analysis of the whole genome sequences of 26 lineage 5 and 6 isolates, and 66 isolates from other lineages within the MTC, reveal that M. africanum does not meet modern criteria to be considered an independent species. We analyzed drug resistance-associated genes and found that drug resistance evolves within these lineages through similar mechanisms as observed for the rest of the MTC in Mali. Though we did not see an elevated number of mutations in virulence-associated genes in these two lineages, we identified a number of lineage-specific mutations, pseudogenes and changes in gene content that may impact virulence and host specificity, and improve, overall, our understanding of what make these lineages unique.

Endocrine effects of real-life mixtures of persistent organic pollutants (POP) in experimental models and wild fish

A series of studies have assessed the occurrence, levels, and potential adverse effects of persistent organic pollutants (POP) in fish from Lake Mjøsa. In this lake, high levels of various POP were detected in biota. Fish from the nearby Lake Losna contain background levels of POP and served as reference (controls) in these studies. Significantly higher prevalence of mycobacteriosis and pathological changes were documented in burbot (Lota lota) from Mjøsa compared to burbot from Losna. Further, transcriptional profiling identified changes in gene expression in burbot from Mjøsa compared to burbot from Losna associated with drug metabolism enzymes and oxidative stress. POP extracted from burbot liver oil from the two lakes was used to expose zebrafish (Danio rerio) during two consecutive generations. During both generations, POP mixtures from both lakes increased the rate of mortality, induced earlier onset of puberty, and skewed sex ratio toward males. However, opposite effects on weight gain were found in exposure groups compared to controls during the two generations. Exposure to POP from both lakes was associated with suppression of ovarian follicle development. Analyses of genome-wide transcription profiling identified functional networks of genes associated with weight homeostasis, steroid hormone functions, and insulin signaling. In human cell studies using adrenocortical H295R and primary porcine theca and granulosa cells, exposure to lake extracts from both populations modulated steroid hormone production with significant difference from controls. The results suggest that POP from both lakes may possess the potential to induce endocrine disruption and may adversely affect health in wild fish.

Mycobacterium abscessus Complex Infections in Humans

Mycobacterium abscessus complex comprises a group of rapidly growing, multidrug-resistant, nontuberculous mycobacteria that are responsible for a wide spectrum of skin and soft tissue diseases, central nervous system infections, bacteremia, and ocular and other infections. M. abscessus complex is differentiated into 3 subspecies: M. abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. abscessus subsp. bolletii. The 2 major subspecies, M. abscessus subsp. abscessus and M. abscessus subsp. massiliense, have different erm(41) gene patterns. This gene provides intrinsic resistance to macrolides, so the different patterns lead to different treatment outcomes. M. abscessus complex outbreaks associated with cosmetic procedures and nosocomial transmissions are not uncommon. Clarithromycin, amikacin, and cefoxitin are the current antimicrobial drugs of choice for treatment. However, new treatment regimens are urgently needed, as are rapid and inexpensive identification methods and measures to contain nosocomial transmission and outbreaks.

Rapidly growing mycobacteria associated with laparoscopic gastric banding, Australia, 2005-2011

Laparoscopic gastric banding is a common bariatric procedure worldwide. Rapidly growing mycobacteria are environmental organisms increasingly seen as pathogens,often in infected prosthetic material. We report 18 cases of infection associated with laparoscopic gastric banding caused by Mycobacterium fortuitum and M. abscessus in Australia during 2005–2011. We identified cases by reviewing positive cultures at the Queensland state reference laboratory or through correspondence with clinicians, and we obtained clinical and epidemiologic data. Eleven cases of M. fortuitum and 7 cases of M. abscessus infection were identified. The port was thought to be the primary site of infection in 10 of these cases. Complications included peritonitis,band erosion, and chronic ulceration at the port site.Rapidly growing mycobacteria can infect both port and band and can occur as either an early perioperative or late infection.Combination antimicrobial therapy is used on the basis of in vitro susceptibilities. Device removal seems to be vital to successful therapy.

Epidemiology and clinical characteristic of mycobacterial infections in human immunodeficiency virus-infected patients in Siriraj Hospital

BACKGROUND

Mycobacterium tuberculosis (MTB) and non-tuberculous mycobacteria (NTM) infections are major health problems in Human Immunodeficiency Virus (HIV)-infected patients. Most previous studies focused mainly on tuberculosis (TB) rather than NTM infections.

OBJECTIVE

To determine clinical features of mycobacterial infections, from both MTB and NTM in HIV-infected patients in Siriraj Hospital.

MATERIAL AND METHOD

A retrospective study of adult HIV-infected patients in Infectious Disease Clinic, Siriraj Hospital, was conducted. Clinical characteristics and factors associated with mycobacterial infections were analyzed.

RESULTS

Of 253 patients enrolled, 65 (25.7%) developed mycobacterial infections, in which 56 patients (86%) were tuberculosis (TB), whereas NTM was diagnosed in 9 (14%). Of these 65 patients, 45 (69.2%) were culture-proven, 14 (21.6%) were diagnosed TB by positive acid-fast bacilli smears and 6 (9.2%) were diagnosed TB by clinical response to anti-tuberculosis treatment only. Among culture-positive patients, MTB was found in 36 (80%) and NTM in 9 (20%), in which Mycobacterium avium complex (MAC) was the most common among NTMisolates (n = 5),followed by unidentifiable slowly-growing mycobacteria (n = 3) and M. fortuitum (n = 1). Among patients with MTB infection, 58.3% were disseminated. The most affected organ in patients with mycobacterial infections was lung (75%), followed by lymph node (66.7%). Factors associated with mycobacterial infections included male gender (64.6% vs. 54.3%; p = 0.026), higher HIV Viral load (1.04 x 10(6) VS. 0.3 x 10(6); p = 0.004), lower hematocrit (32.7% vs. 35.3%; p = 0.032) and higher alkaline phosphatase (ALP) (146 U/L vs. 107 U/L;p = 0.032). In contrast, Pneumocystis pneumonia (PCP) was negatively associated with mycobacterial infections in HIV-infected individuals (28.8% vs. 10.9%; p = 0.004). Favorable treatment response was 86.1% and 77.8% for MTB and NTM infection, respectively, and the 6-month mortality rates were 2.78% and 11.1% for MTB and NTM infection, respectively. In patients who received treatment for TB, 22.2% had hepatitis, 13.9% had drug allergy and 8.3% had immune reconstitution inflammatory syndrome.

CONCLUSION

Disseminated infection is the most common form of mycobacterial infection in HIV-infected patients, resulting in anemia and high ALP levels. PCP was negatively associated with mycobacterial infection. MAC is the most common of the NTM isolates in HIV-infected patients.

High-level relatedness among Mycobacterium abscessus subsp. massiliense strains from widely separated outbreaks

Three recently sequenced strains isolated from patients during an outbreak of Mycobacterium abscessus subsp. massiliense infections at a cystic fibrosis center in the United States were compared with 6 strains from an outbreak at a cystic fibrosis center in the United Kingdom and worldwide strains. Strains from the 2 cystic fibrosis outbreaks showed high-level relatedness with each other and major-level relatedness with strains that caused soft tissue infections during an epidemic in Brazil. We identified unique single-nucleotide polymorphisms in cystic fibrosis and soft tissue outbreak strains, separate single-nucleotide polymorphisms only in cystic fibrosis outbreak strains, and unique genomic traits for each subset of isolates. Our findings highlight the necessity of identifying M. abscessus to the subspecies level and screening all cystic fibrosis isolates for relatedness to these outbreak strains. We propose 2 diagnostic strategies that use partial sequencing of rpoB and secA1 genes and a multilocus sequence typing protocol.

Nosocomial Mycobacterial Pseudoinfection in a Georgia Hospital

Nosocomial pseudoepidemics may be detected when clustering of pseudoinfections occur or when artificial clusters of real infection are observed. Nontuberculous mycobacteria were reportedly isolated from specimens obtained from seven patients at one hospital from October 1980 to January 1981. Because the patients' clinical illnesses were not uniformly consistent with mycobacterial disease, we hypothesized that pseudoinfections had occurred and searched for a common source of contamination. The investigation suggested that specimen contamination was associated with one microbiology laboratory technician: 6 of 22 (27%) specimens processed by that person were positive compared with 1 of 103 (1%) specimens processed by the other five technicians. However, a specific mechanism of contamination was not identified. Nosocomial pseudoepidemics associated with false infections should be suspected and investigated when clinical features and laboratory findings do not agree.

Mycobacterium simiaeOutbreak Associated With a Hospital Water Supply

Objective:

Mycobacterium simiaeis found primarily in the southwestern United States, Israel, and Cuba, with tap water as its suspected reservoir. Our institution saw an increase inM. simiaeisolates in 2001. An investigation into possible contaminated water sources was undertaken.

Design:

Environmental cultures were performed from water taps in the microbiology laboratory, patient rooms, points in the flow of water to the hospital, and patients' homes. Patient and environmentalM. simiaewere compared by PFGE.

Setting:

Military treatment facility in San Antonio, Texas.

Patients:

All patients with cultures positive forM. simiaebetween January 2001 and April 2002. Medical records were reviewed.

Results:

M. simiaewas recovered from water samples from the hospital, patients' home showers, and a well supplying the hospital. A single PFGE clone was predominant among water isolates (9 of 10) and available patient isolates (14 of 19). There was an association between exposure to hospital water and pulmonary samples positive for the clonalM. simiaestrain (P= .0018). Only 3 of 22 culture-positive patients met criteria forM. simiaepulmonary disease. Of them, two had indistinguishableM. simiaestrains from tap water to which they were routinely exposed.

Conclusions:

This represents an outbreak ofM. simiaecolonization with one nosocomial infection. It is only the second time thatM. simiaehas been recovered from hospital tap water and its first presentation in municipal water. This study raises issues about the need and feasibility of eliminating or avoiding exposure toM. simiaefrom tap water.

Distribution and respiratory activity of mycobacteria in household water system of healthy volunteers in Japan

The primary infectious source of nontuberculous mycobacteria (NTM), which are known as opportunistic pathogens, appears to be environmental exposure, and it is important to reduce the frequency of exposure from environmental sources for preventing NTM infections. In order to achieve this, the distribution and respiratory activity of NTM in the environments must be clarified. In this study, we determined the abundance of mycobacteria and respiratory active mycobacteria in the household water system of healthy volunteers using quantitative PCR and a fluorescent staining method, because household water has been considered as one of the possible infectious sources. We chose healthy volunteer households in order to lessen the effect of possible residential contamination from an infected patient. We evaluated whether each sampling site (bathroom drain, kitchen drain, bath heater pipe and showerhead) have the potential to be the sources of NTM infections. Our results indicated that drains in the bathroom and kitchen sink are the niche for Mycobacterium spp. and M. avium cells were only detected in the bathtub inlet. Both physicochemical and biologic selective pressures may affect the preferred habitat of Mycobacterium spp. Regional differences also appear to exist as demonstrated by the presence (US) or absence (Japan) of Mycobacterium spp. on showerheads. Understanding of the country specific human activities and water usage will help to elucidate the infectious source and route of nontuberculous mycobacterial disease.

Optimising and evaluating the characteristics of a multiple antigen ELISA for detection of Mycobacterium bovis infection in a badger vaccine field trial

A long-term research programme has been underway in Ireland to evaluate the usefulness of badger vaccination as part of the national bTB (bovine tuberculosis) control strategy. This culminated in a field trial which commenced in county Kilkenny in 2009 to determine the effects of badger vaccination on Mycobacterium bovis transmission in badgers under field conditions. In the present study, we sought to optimise the characteristics of a multiplex chemiluminescent assay for detection of M. bovis infection in live badgers. Our goal was to maximise specificity, and therefore statistical power, during evaluation of the badger vaccine trial data. In addition, we also aimed to explore the effects of vaccination on test characteristics. For the test optimisation, we ran a stepwise logistic regression with analytical weights on the converted Relative Light Units (RLU) obtained from testing blood samples from 215 badgers captured as part of culling operations by the national Department of Agriculture, Food and the Marine (DAFM). The optimised test was applied to two other datasets obtained from two captive badger studies (Study 1 and Study 2), and the sensitivity and specificity of the test was attained separately for vaccinated and non-vaccinated badgers. During optimisation, test sensitivity was maximised (30.77%), while retaining specificity at 99.99%. When the optimised test was then applied to the captive badger studies data, we observed that test characteristics did not vary greatly between vaccinated and non-vaccinated badgers. However, a different time lag between infection and a positive test result was observed in vaccinated and non-vaccinated badgers. We propose that the optimized multiplex immunoassay be used to analyse the vaccine trial data. In relation to the difference in the time lag observed for vaccinated and non-vaccinated badgers, we also present a strategy to enable the test to be used during trial evaluation.

Characterization of Mycobacterium salmoniphilum as causal agent of mycobacteriosis in Atlantic salmon, Salmo salar L., from a freshwater recirculation system

Thirty Atlantic salmon, Salmo salar L., with low corporal condition relative to other fish present in the culture system, were sampled from a freshwater recirculation pisciculture located in Chile. The most characteristic signs and lesions were cachexia and presence of multiple greyish-white granulomas within internal organs. The external and internal lesions, along with the microscopic, histologic and biochemical findings, were consistent with mycobacteriosis. The identification of Mycobacterium salmoniphilum as the causal agent of the lesions was possible through the use of molecular analyses. This study represents the first report of Mycobacterium salmoniphilum in a freshwater recirculation system and the first case of fish mycobacteriosis described in Chile.

[Infectious events during the first year of treatment with an antagonist of the tumor necrosis factor]

OBJECTIVE

To assess the incidence of severe infections in patients treated with anti-TNF-??drugs, during the first year of treatment with these drugs.

MATERIALS AND METHOD

Retrospective observational study carried out at a general hospital from a sample of patients receiving their first anti-TNF-??drug, according to approved indications, to treat a rheumatic disease. Each patient follow-up lasted for 2 years: the year before receiving the drug and the year after starting on this therapy. We considered those severe infectious events requiring hospital admission. A cohort study was performed before-after. The incidence rates of number of events (infections) per 100,000 inhabitants/year for the first treatment year and the previous year (control period) were calculated. The relative risk was calculated.

RESULTS

We included 196 patients. Twelve severe infectious events were recorded during the first treatment year, with a relative risk of 2.4. The biological drug most frequently associated to infection was Adalimumab. All patients having an infection had been previously or concomitantly treated with Methotrexate, and 90.6% with glucocorticosteroids. The main location of the infection was the respiratory system (58.3%), and the gram-positive microorganisms were the most frequent (58.3%).

CONCLUSIONS

The use of anti-TNF-??drugs, and mainly Adalimumab, represents a risk factor for suffering severe infections, mainly at the respiratory tract, produced by gram-positive microorganisms. The use of immunosuppressive drugs such as Methotrexate and glucocorticosteroids seems to increase the risk for such events.

Comparative Evaluation of theIn VitroAntimycobacterial Activities of Six Aminoglycoside Antibiotics Using an Agar Dilution Method

Given the increasing prevalence of mycobacterial resistance to aminoglycoside antibiotics, we examined the susceptibility of 76 clinical isolates of mycobacteria to arbekacin, amikacin, gentamicin, kanamycin, tobramycin and streptomycin using an agar dilution method. Only arbekacin and amikacin showed excellent therapeutic potential (minimum inhibitory concentrationis (MICs) < or =0.25-4 microg/ml) against 30 isolates of rapidly growing mycobacteria, including Mycobacterium fortuitum, M. chelonae and a related organism, Nocardia asteroides. The MIC(90)of tobramycin against 23 isolates of M. avium complex was 8 microg/ml, while that of the other 5 aminoglycosides ranged from 64-256 microg/ml. Of the 23 M. tuberculosis isolates tested, 5 showed aminoglycoside resistance (MICs 128 to > or =1,024 microg/ml), while the others were variably susceptible (MICs < or =0.25-32 microg/ml) to all 6 aminoglycosides. The chemotherapeutic potential of arbekacin, amikacin and streptomycin as treatment of tuberculosis was apparent; however, proper patient management would be required to control against the emergence of the drug-resistant strains during prolonged treatment.

Incidence of tuberculosis and mycobacteriosis among HIV-infected patients--clinical and epidemiological analysis of patients from north-eastern Poland

INTRODUCTION

According to WHO data, among patients infected with HIV, tuberculosis occurs in about 30% of patients and causes approximately 25% of deaths due to AIDS worldwide. The incidence rate of tuberculosis in the Polish population was 22.2/100,000 in 2011, while the average in European Union countries in 2011 was 14/100,000. Since 1985 to 30 April 2013 HIV infection in Poland was confirmed in 16,588 patients, while the number of reported tuberculosis cases in HIV-infected individuals in 2011 was 26. The aim of this study was to assess the prevalence and clinical course of tuberculosis and mycobacterial disease in HIV-infected patients treated in the Department of Infectious Diseases and Hepatology in Białystok.

MATERIAL AND METHODS

We analysed documentation of 577 HIV-infected patients, their demographic data, epidemiological status, degree of immunosuppression (T CD4 and CD8 numbers) and stage of HIV infection.

RESULTS

Complete follow-up was possible in 389 patients, of whom 265 (68%) were male. Tuberculosis (TB) was diagnosed in 41 patients (10.5%) and mycobacteriosis in 4 patients (1.03%). In 19 patients (42%) HIV and TB or mycobacteriosis were diagnosed simultaneously. The median CD4 T lymphocyte count was lower in patients with a simultaneous diagnosis of HIV and tuberculosis or mycobacteriosis compared to the group in whom TB/mycobacteriosis was diagnosed later. The number of CD4 T-cells less than 50 cells/μL was found in 63.2% (12/19) of patients when HIV and TB or mycobacteriosis were diagnosed simultaneously and in 38.5% (10/26) of patients who were diagnosed with TB or mycobacteriosis later than the HIV infection (p = 0.14). The median HIV viral load in patients in whom HIV infection and tuberculosis or mycobacteriosis were diagnosed at the same time was higher than in other patients and this difference was statistically significant. Pulmonary tuberculosis was the most common form of clinical disease and accounted for 60% of all cases. Among the analysed cases with HIV and tuberculosis or mycobacteriosis coinfection, tuberculosis or mycobacteriosis was the cause of death in 8 patients, and 9 died of other causes.

CONCLUSION

In our material of 389 HIV-infected patients, tuberculosis was diagnosed in 41 (10.5%) and mycobacterial diseases in 4 (1.03%). In 42% of co-infected patients (HIV+TB or mycobacteriosis) the diagnosis of both diseases was made at the same time. In these patients, a deep deficit of cellular immunity (CD4 < 50 cells/μL) was observed more frequently than in patients diagnosed with TB or mycobacteriosis in the later course of HIV. HIV RNA viral load was significantly higher in the group diagnosed simultaneously than in the remaining patients with HIV and TB or mycobacteriosis coinfection.

A low prevalence of mycobacteria in freshwater fish from water reservoirs, ponds and farms

A survey of the occurrence of mycobacteria was conducted from 717 freshwater fish (25 species) in two water reservoirs, five ponds and two farms in the Czech Republic. A total of 2182 tissue samples from these fish were examined using the conventional culture method. Thirteen mycobacterial isolates were obtained from 12 (1.7%) fish belonging to nine species. Isolates were identified using sequence analysis of the 16SrRNA gene as: Mycobacterium algericum, M. fortuitum, M. gordonae, M. insubricum, M. kumamotonense, M. nonchromogenicum, two isolates of M. peregrinum, M. terrae and M. triplex. Mycobacteria were isolated more frequently from fish skin and gills than from internal organs or muscles.

Non-tuberculous mycobacteria isolated from slaughter pigs in Mubende district, Uganda

BACKGROUND

The importance of infections caused by non-tuberculous mycobacteria (NTM) in animals and humans has gained considerable recognition during the past few years. In the developed world, where pig production is extensively practiced, studies on mycobacterial infections and related control strategies have received increasing attention. The infections are reported to be caused by a wide spectrum of NTM. Unfortunately, these infections have been less recognized in sub-Saharan Africa owing to lack of awareness and systematic studies. In this study we aimed at isolating and identifying species of mycobacteria involved in causing infections in slaughter pigs in Mubende district of Uganda. Furthermore we wanted to identify factors associated with infection prevalence in the study area.

METHODS

A total of 363 lymph nodes were collected and cultured for the presence of mycobacteria. Isolates were identified by 16S rDNA gene sequencing. A questionnaire survey was administered to identify production related factors associated with infection prevalence. Data were assembled and analysed using descriptive statistics and mixed effects logistic regression analysis.

RESULTS

Mycobacteria were detected in 39 % (143/363) of the examined lymph nodes, 63 % (59/93) of lymph nodes with gross lesions typical of mycobacteriosis and 31% (84/270) of lymph nodes with no visible lesions. Nineteen per cent of the isolated mycobacteria were identified as Mycobacterium (M) avium, of these 78% and 22% were M. avium sub sp. Hominissuis and avium respectively. Other mycobacterial species included M. senuense (16%), M. terrae (7%) and M. asiaticum (6%). This study found free range systems (OR = 3.0; P = 0.034) and use of water from valley dams (OR = 2.0; P = 0.049) as factors associated with high prevalence of mycobacteria in slaughter pigs.

CONCLUSIONS

This study demonstrated a high prevalence of NTM infections among slaughter pigs in Mubende district of Uganda. M. avium was the most prevalent of all NTM isolated and identified. Free range system of pig management and valley dam water were the most significant factors associated with NTM prevalence in Mubende district. These findings could be of a major public health concern given that it is in a predominantly pork consuming population with 18% HIV/AIDS prevalence. Therefore, stringent post-mortem inspection at the slaughter houses is of paramount importance to reduce human exposure.

[Clinical features of chronic granulomatous disease]

OBJECTIVE

Chronic granulomatous disease (CGD) is a rare primary immunodeficiency of phagocytic oxidative bursts leading to recurrent severe bacterial and fungal infections as well as granuloma formation. There were few reports on the clinical characteristics of this disease in China. The purpose of this study was to evaluate the clinical features of 48 Chinese cases with CGD which were confirmed by clinical features, dihydrorhodamine (DHR) assay and gene mutation analysis.

METHOD

The study cohort was the population of CGD patients diagnosed in Children's Hospital of Fudan University from January, 2004, to June, 2011. Cases included in our analysis were restricted to those who had complete data of the clinical symptoms and laboratory tests. The patients were followed up by outpatient visiting and telephone call regularly for 0.5 to 6 years. The history and data of physical examination and treatment of 48 cases were collected and reviewed.

RESULT

All the patients were diagnosed by DHR analysis. The age of onset of all the 48 patients were less than 6 months, including 43 male and 5 female. The mean age at diagnosis was 2.42 years; 12 patients were infants under six months, 10 were between 6 and 12 months, 9 were between 1 and 2 years, 5 patients were between 2 and 3 years, 4 were between 4 and 5 years, and 8 were between 6 and 10 years. Recurrent respiratory infection (44/48) and chronic diarrhea (31/48) were the common symptoms in all the patients, and then skin lesion (22/48), including marked reaction at BCG infected site, pustular eruption and infected skin ulcer and urinary tract infection (3/48) were also general symptoms in our study. In addition, lymphadenectasis occurred in 31 cases and 23 of them were considered to be associated with BCG vaccination. The pathogens caused the infection were mycobacteria (52.08%), fungi (43.75%) and pyogenic bacteria. Thirty-seven patients had mutations in CYBB/CYBA/NCF1/NCF2 genes. Recombinant human interferon-gamma (rhIFN-γ) plus sulfamethoxazole were used for the prevention and treatment of infection, the frequency and severity of the disease could be reduced.

CONCLUSION

The age at onset and diagnosis of the present group of CGD was younger. Clinical symptoms were associated with recurrent mycobacterial, fungal and pyogenic bacterial infection, which involved respiratory tract, alimentary tract, skin and lymph node. rhIFN-γ partially improved the prognosis of CGD.

Mycobacterial infection in the ferret

Mycobacteriosis is an important disease in the feral ferret (Mustela putorius furo) of New Zealand; elsewhere, reports of tuberculosis in the ferret are sporadic. Genus Mycobacterium consists of aerobic, non-spore-forming, gram-positive, nonmotile bacteria that characteristically feature a cell wall rich in mycolic acids and esters. The epidemiology of mycobacteriosis in the ferrets of New Zealand involves complex interactions between ferrets, possums, and livestock. Investigators have shown that the ferret is highly susceptible only to Mycobacterium bovis infection and is more resistant to infection by other Mycobacterium spp. The principal site of all mycobacterial infection in the ferret is the gastrointestinal tract.