Emergence of Clinically Relevant Non-Tuberculous Mycobacterial Infections in Saudi Arabia

Abstract

BackgroundNon-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 findingsDuring 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/SignificanceThe 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.

Tuberculosis in Saudi Arabia: the journey across time

“…In addition, 62.1% of the total study subjects were Saudi nationals. This study concluded that Saudi Arabia has an increasing magnitude of true NTM diseases [38].…”

“…Therefore, building a new registry that can be accessed via internet by the respective users in the NTP, particularly for physicians treating patients, is essential and highly recommended. : Nationwide species diversity of non-tuberculous mycobacteria in Saudi Arabia [38] Need for a central referral research laboratory facility…”

“…As a country with the highest rate (58%) of consanguinity reported in the world and a prevalence of numerous genetic disorders, the potential of all the identified and unexplored genetic factors needs to be investigated [46,47]. Recent studies have shown that the indigenous population is affected by EPTB, NTM infections, BCG vaccine-related complications, and an upward trend of pulmonary tuberculosis [5,38]. The major assumption is that the Saudi population may have certain genetic susceptibilities towards mycobacterial diseases.…”

Epidemiology of Human Pulmonary Infection with Nontuberculous Mycobacteria

“…In a single institution in Israel, among 215 patients identified with pulmonary NTM isolation over 2004–2010, 21% (45/215) were judged to have definite or probable disease, but clinical information was not detailed (61). From various laboratories in Saudi Arabia, a sample of 95 patients with NTM isolation was identified during 2009–2010, including 73 patients with pulmonary isolation, 67% of whom (49/73) were judged to have pulmonary disease but clinical information was not detailed (62). In Oman, over 2006–2007, a random sample of 13 NTM isolates from the Central Public Health Laboratory in Muscat, was selected for case review (63).…”

Emergence of Rare Species of Nontuberculous Mycobacteria as Potential Pathogens in Saudi Arabian Clinical Setting

“…Following the global trend of NTM prevalence, Saudi Arabia also reports with an increasing numbers of NTM diseases [7, 9]. In 2013, Varghese et al reported in the first national level study a highly diverse population of clinically relevant NTM’s with the potential of causing pulmonary and extra-pulmonary diseases [9].…”