Emergence of clinically relevant Non-Tuberculous Mycobacterial infections in Saudi Arabia.

BACKGROUND: Non-Tuberculous Mycobacteria (NTM) are emerging around the world due to a higher prevalence of immunosuppressive illness and therapy. Saudi Arabia is not an exception as there have been novel mycobacterial species also identified. In addition, several published case reports from different parts of the country suggest a growing pathogenic potential of NTM. As the first nationwide study, we sought to gain an insight into the species diversity of NTM clinical isolates. METHODOLOGY/PRINCIPAL FINDINGS: During June 2009-July 2010, 95 clinical isolates were collected from tuberculosis reference laboratories in major provinces within Saudi Arabia and subjected to standard line probe assay techniques to identify their species. Diagnostic guidelines of the American Thoracic Society were applied to determine the clinical relevance of respiratory isolates. Species diversity (13 species) was very high and dominated (61.0%) by rapid growing NTM. The major species obtained were Mycobacterium abscessus, M. fortuitum, M. intracellulare followed by M. kansassi, M. gordanae and M. avium. Interestingly this study reports for the first time the clinical relevance of M. celatum, M. xenopi, M. scrofulceum, M. lentiflavum, M. asiaticum and M. simiae in Saudi Arabia. Of the total, 67.1% were clinically relevant respiratory cases, 23.2% were non-respiratory cases and 9.7% were respiratory colonizers. Coexisting illness was reported in 53.7% of the studied cases. The major risk factors observed among the patients were previous history of tuberculosis, chronic obstructive pulmonary disorder and human immunodeficiency virus infection. CONCLUSION/SIGNIFICANCE: The high rates of clinically confirmed respiratory cases suggest that NTM infections are indeed a new challenge to health authorities. The current findings show an opposite picture of the Western world where M. avium complex and particularly slow growing NTM are the most predominant respiratory pathogens. The complexity of species demands an immediate strengthening of the current diagnostic facilities

Al-Hajoj, “Emergence of clinically relevant non-tuberculous mycobacterial infections

Background: Non-Tuberculous Mycobacteria (NTM) are emerging around the world due to a higher prevalence of immunosuppressive illness and therapy. Saudi Arabia is not an exception as there have been novel mycobacterial species also identified. In addition, several published case reports from different parts of the country suggest a growing pathogenic potential of NTM. As the first nationwide study, we sought to gain an insight into the species diversity of NTM clinical isolates. Methodology/Principal findings: During June 2009–July 2010, 95 clinical isolates were collected from tuberculosis reference laboratories in major provinces within Saudi Arabia and subjected to standard line probe assay techniques to identify their species. Diagnostic guidelines of the American Thoracic Society were applied to determine the clinical relevance of respiratory isolates. Species diversity (13 species) was very high and dominated (61.0%) by rapid growing NTM. The major species obtained were Mycobacterium abscessus, M. fortuitum, M. intracellulare followed by M. kansassi, M. gordanae and M. avium. Interestingly this study reports for the first time the clinical relevance of M. celatum, M. xenopi, M. scrofulceum, M. lentiflavum, M. asiaticum and M. simiae in Saudi Arabia. Of the total, 67.1 % were clinically relevant respiratory cases, 23.2 % were non-respiratory cases and 9.7 % were respiratory colonizers. Coexisting illness was reported in 53.7 % of the studied cases. The major risk factors observed among the patients were previous history of tuberculosis, chroni

Incidence of and risk factors associated with pulmonary and extra-pulmonary tuberculosis in Saudi Arabia (2010-2011).

SETTING: National Tuberculosis Program, Department of Public Health, Ministry of Health, Kingdom of Saudi Arabia (KSA). OBJECTIVE: To summarize data on the incidence of tuberculosis and associated risk factors for cases reported during 2010-2011. DESIGN: Retrospective analysis of routinely collected data through an established national disease notification system of the Ministry of Health in KSA. RESULTS: The estimated incidence of all forms of tuberculosis fell from 15.8/100000 (95% CI: 15.3/100,000-16.3/100,000) in 2010 to 13.8/100,000 (95% CI: 13.4/100,000-14.2/100,000) in 2011. Saudis experienced a decrease from 11.8/100,000 (95% CI: 11.3/100,000 to 12.3/100,000) in 2010 to 9.9/100,000 (95% CI: 9.5/100,000-10.4/100,000) in 2011 while the incidence in non-Saudis declined from 24.7/100,000 (95% CI: 23.6/100,000 to 25.7/100,000) in 2010 to 22.5/100,000 (95% CI: 21.5/100,000 to 23.4/100,000) in 2011. The proportion of Extra Pulmonary TB (EPTB) which increased minimally from 30% in 2010 to 32% in 2011 was higher than global figures and strongly associated with age, sex, nationality and occupation. CONCLUSION: The current estimated incidence of about 14/100,000 in 2011 is less than half its estimated value of 44/100000 in 1990. Without prejudice to any under-reporting, the KSA appeared to be on the course for TB elimination by 2050 having reached the first milestone set by WHO. The proportion of EPTB remains higher than global figure and age, sex, nationality and occupation were significant independent predictors of EPTB

Tuberculosis transmission among immigrants and autochthonous populations of the eastern province of Saudi Arabia.

BACKGROUND:Eastern province of Saudi Arabia is an industrial zone with large immigrant population and high level of tuberculosis case notification among immigrants. The impact of immigration and current trends of tuberculosis transmission among immigrants and autochthonous population in the region had not been investigated so far using molecular tools. METHODOLOGY:During 2009- 2011, a total of 524 Mycobacterium tuberculosis isolates were collected from the central tuberculosis reference laboratory, representing an estimated 79.2% of the culture-positive tuberculosis cases over the study period in the province. These isolates were genotyped by using 24 locus-based MIRU-VNTR typing and spoligotyping followed by first line drug susceptibility testing. The molecular clustering profiles and phylogenetic diversity of isolates were determined and compared to the geographical origins of the patients. PRINCIPLE FINDINGS:Genotyping showed an overall predominance of Delhi/CAS (29.4%), EAI (23.8%) and Ghana (13.3%) lineages, with slightly higher proportions of Delhi/CAS among autochthonous population (33.3 %) and EAI (30.9%) among immigrants. Rate of any drug resistance was 20.2% with 2.5% of multi-drug resistance. Strain cluster analysis indicated 42 clusters comprising 210 isolates, resulting in a calculated recent transmission index of 32.1%. Overall shared cluster ratio was 78.6% while 75.8% were shared between autochthonous population and immigrant population with a predominance of immigrants from South east Asia (40.7%). In contrast, cross national transmission within the immigrant population was limited (24.2%). Younger age (15-30- p value-0.043, 16-45, p value 0.030), Saudi nationality (p value-0.004) and South East Asian origin (p value-0.011) were identified as significant predisposing factors for molecular strain clustering. CONCLUSIONS:The high proportion of molecular clusters shared among the autochthonous and immigrant populations suggests a high permeability of tuberculosis transmission between both populations in the province. These results prompt for the need to strengthen the current tuberculosis control strategies and surveillance programs

Demographical and Clinical summary of 42 study subjects.

a<p>Primary Immunodeficiency.</p>b<p>Severe combined immunodeficiency.</p><p>Demographical and Clinical summary of 42 study subjects.</p

Summary of the 73 pulmonary samples with NTM infections during 2009–2010 from Saudi Arabia.

*<p>Based on ATS/IDSA 2007 guidelines.</p>†<p>Previous mycobacterium tuberculosis disease.</p>‡<p>Human immunodeficiency virus.</p>¶<p>Pulmonary fibrosis.</p>#<p>Cystic fibrosis.</p>±<p>Chronic obstructive pulmonary disease.</p>++<p>Continuous ambulatory peritoneal dialysis.</p

Summary of the 22 extra-pulmonary NTM infections observed in the study.

†<p>Lymphnode/Fine Needle Aspiration/Biopsy.</p>¶<p>Previous mycobacterium tuberculosis disease.</p>‡<p>Cystic fibrosis.</p>*<p>Human immunodeficiency virus.</p

Overall species diversity of 95 clinical non-tuberculous mycobacterial isolates from Saudi Arabia.

<p>The diagram shows collective representation of pulmonary and extra-pulmonary isolates. The number of isolates with particular species are showed at the outer end of the bar diagram.</p

Summary of the study subjects.

<p>Summary of the study subjects.</p

The distribution of smear positives, negative and EPTB in new tuberculosis patients in Saudi Arabia by nationality and year.

<p>The distribution of smear positives, negative and EPTB in new tuberculosis patients in Saudi Arabia by nationality and year.</p