Home Browse Non-tuberculous mycobacterium isolations from tuberculosis presumptive...
ALL Metrics
-
Views
-
Downloads
Get PDF
Get XML
Cite
Export
Track
▬
✚
Research Article
Revised

Non-tuberculous mycobacterium isolations from tuberculosis presumptive cases at the National Tuberculosis Reference Laboratory Kenya, 2018–2019

[version 2; peer review: 1 approved, 2 not approved]
George Kamau
https://orcid.org/0000-0003-1556-4434
1-3, Zakayo Mwangi
https://orcid.org/0000-0002-3608-6892
4, Joel Bargul3, [...] Maurice owiny2, Nellie Mukiri5, Immaculate Kathure6, Beatrice Khamala5, Nassoro Mwanyalu2, Richard Kiplimo7, Raphael Lihana1
George Kamau
https://orcid.org/0000-0003-1556-4434
1-3, Zakayo Mwangi
https://orcid.org/0000-0002-3608-6892
4, [...] Joel Bargul3, Maurice owiny2, Nellie Mukiri5, Immaculate Kathure6, Beatrice Khamala5, Nassoro Mwanyalu2, Richard Kiplimo7, Raphael Lihana1
PUBLISHED 09 Jul 2024
Author details Author details
OPEN PEER REVIEW
REVIEWER STATUS

Abstract

Background: Mycobacterial pathogens are among the top causes of diseases in humans. In Kenya, incidences of Non-Tuberculous Mycobacteria (NTM) species have steadily been on the increase. Most NTMare resistant to first line treatment of tuberculosis and have a challenge in timely and accurate diagnosis. Misdiagnosis has led to prescribing anti-tuberculosis regimens to patients suffering from NTM. We aimed to determine the most prevalent Non-Tuberculous Mycobacterium in Kenya.

Methods: We reviewed records from the National Tuberculosis Reference Laboratory(NTRL ) Laboratory information management system (LIMS) between January 2018 and December 2019 for the patients on surveillance. All isolates were cultured in Mycobacterial Growth Indicator Tubes (MGIT) and incubated for detection using BACTEC™ MGIT™ system. Those with negative acid-fast bacilli (AFB) growth and negative for Mycobacterium Tuberculosis Complex Species (MTBC) protein-MPT64 were suggestive of NTM infections, which were sub-cultured in MGIT and characterized using Line Probe Assay (LPA) GenoType® MTBDR CM/AS. Descriptive and bivariate analysis was done.

Results: Of the total 24,549 records reviewed, 167(0.7%) were NTM isolates. Males comprised of 74.2% (124/167), and the mean age was 42 years (SD±16), age group 35-44 years had the highest NTM at 26.3% (44/167). Nairobi had 12.6% (21/167), Mombasa 10.8% (18/167), Kilifi and Meru each had 7.8% (13/167). Eleven isolated species comprised of Mycobacterium intracellulare 35.3% (65/167), M. fortuitum at 27% (48/167), and M. scrofulaceum at 10.2% (17/167). Previously treated patients had higher NTM [63.5% (106/167)] than Drug-resistant follow-up patients [26.9% (45/167)]. Coinfection with HIV was at 27.5% (46/167).

Conclusion: Previously treated patients should have an additional screening of NTMS, and drug susceptibility testing should be done before initiation of treatment.

Keywords

Nontuberculous Mycobacteria, Kenya, Mycobacterium avium Complex, Mycobacterium tuberculosis, Prevalence

Corresponding author: George Kamau
Competing interests: No competing interests were disclosed.
Grant information: The author(s) declared that no grants were involved in supporting this work.
Copyright:  © 2024 Kamau G et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
How to cite: Kamau G, Mwangi Z, Bargul J et al. Non-tuberculous mycobacterium isolations from tuberculosis presumptive cases at the National Tuberculosis Reference Laboratory Kenya, 2018–2019 [version 2; peer review: 1 approved, 2 not approved]. F1000Research 2024, 12:1104 (https://doi.org/10.12688/f1000research.135106.2) First published: 04 Sep 2023, 12:1104 (https://doi.org/10.12688/f1000research.135106.1) Latest published: 09 Jul 2024, 12:1104 (https://doi.org/10.12688/f1000research.135106.2)

Revised Amendments from Version 1

I have expounded on the inclusion criteria and exclusion criteria, added a  table with the rapid and slow growers and refined the conclusion.

See the authors' detailed response to the review by Durga Shankar Meena

Introduction

Humans are often affected by Mycobacterium infections. In developing countries, non-tuberculous mycobacterial (NTM) infections have been overshadowed by high incidences of tuberculosis. This trend is, however, fast-changing. The number of new infections is increasing due to the growing number of immune-deficient patients (Ferreira et al., 2002) and nonsterile endoscopic medical devices (Duarte et al., 2009). Pulmonary diseases caused by NTM have been on the increase worldwide (Hoefsloot et al., 2013). In 2014 estimated prevalence of pulmonary tuberculosis caused by NTM was estimated to be 33–65 per 100,000 persons (Morimoto et al., 2014).

Globally, positive acid-fast bacilli (AFB) specimens are assumed to develop Mycobacterium tuberculosis (MTBC) and are therefore managed by anti-tuberculosis agents whereas some are put under speculated areas (Mertaniasih et al., 2017). The high prevalence of AFB leads to isolation of mycobacterial illness, meaning that more patients with AFB-positive samples have been administered unsuitable and, more so, unnecessary empirical anti-tuberculosis treatment (Ngayo et al., 2015). As a result of this incorrect treatment and high treatment letdown, the mortality of patients with lung infections is increasing. Therefore, appropriate diagnosis and regular monitoring are crucial in monitoring and treating patients (Aksamit et al., 2014).

In Kenya, data regarding the burden of pulmonary illness is scanty, partly due to constraints in surveillance and diagnosis of mycobacterial species. Distribution of these species (NTM) contributes to the difficulties in interpreting positive culture results. Furthermore, it is not mandatory to report cases of disease to the database at the Ministry of Health; thus, data regarding the epidemiology and distribution of pulmonary disease’s causation is inadequate in Kenya (Jacqueline et al., 2015). The decision to initiate treatment should be influenced by the severity of disease, the risk of progressive NTM-pulmonary disease, the presence of comorbidity and the goals of treatment. Decision to treat remains individualized with consultations and individuals may require a period of longitudinal assessment (symptoms, radiological change and mycobacterial culture results) to inform NTM treatment decisions. To determine the clinical relevance of NTM positive cultures, it is essential to distinguish transient or persistent colonization (which is usually not treated) from true infection (Daley et al., 2020). It’s against this background that the current study was undertaken to characterize the NTM.

Methods

Ethical clearance

This study was approved by Kenyatta National Hospital-University of Nairobi Ethics Review Committee (Ref:KNH-ERC/A/306) on September 14, 2020. Waiver for individual informed consent was granted as the study utilized remnant clinical samples and the research posed no greater than minimal risk to the study subjects.

Inclusion criteria

All AFB positive samples which are Mycobacterium tuberculosis complex (MTBC) negative by line probe assay are screened for NTM. After culture growth all AFB positive and MPT64 antigen test negative, are also screened for NTM.

Exclusion criteria

All AFB positive samples with MTBC confirmation are exclude and culture growths which are AFB negative also excluded.

Samples, processing, mycobacterial culture, and growth identification

Sputum samples were collected in a leak proof container with a volume of >3ml, which were labelled with client name, date of sample collection and client registration number. The samples were accompanied by a duly filled request form and transported in triple package which were received at the National Tuberculosis Reference Laboratory (NTRL)] underwent mycobacterial culture and identification procedures as described in NTRL standard operating procedures (SOP). Where sputum samples were decontaminated and digested using the N-acetyl-L-cysteine 2% NaOH (NALC-NaOH) procedure. Inoculation into mycobacteria growth indicator tube (MGIT) and Lowenstein-Jensen (LJ) media was done and incubated at 37°C. Growth monitoring for up to 6 and 8 weeks respectively, was done. At the same time, sputum smears were prepared, air dried, heat-fixed then fluorochrome stained with Auramine O. Appearance of mycobacteria as bright yellow fluorescent rods was definitive of correct diagnosis when viewed under a light-emitting diodes microscope. Upon thorough mixing, the tubes were centrifuged at 14,000g for five minutes. The supernatant was gathered in distinct 1.5ml tubes for onward processing. Culture growth in liquid and solid media went through MTB identification using Ag MPT64 assay (capilia), the positive ones were excluded in the study and the negative samples underwent ZN microscopy and presence of AFB indicating a possible NTM.

Extraction of DNA

Mycobacterial DNA was extracted from 500 μL of re-suspended colonies using GenoLyse (Hain Lifescience, Nehren,Germany) (106477), according to the manufacturer’s instructions. Briefly, 100ul of lysis buffer (A-LYS) was added to each cryovial containing the resuspended colonies and incubated for five minutes at 95°C after which 100ul neutralization buffer (A-NB) was added and centrifugation was done at 5000g for 10 minutes. The supernatant was transferred to a newly labeled cryovial awaiting PCR. A conventional PCR targeting the hsp65 gene was conducted using the GoTaq Green Master Mix (Promega, Madison, Wisconsin, USA) in a final reaction volume of 13 μl comprising 6.25 μl of 2X GoTaq Hot Start Green Master Mix, 2.5 μl DNA template, 0.25 μl of each of both F-(5′-ACCAACGATGGTGTGTCCAT-3′) and R-(5′-CTTGTCGAACCGCATACCCT-3′) primers at a final concentration of 10 pmoles, and 3.75 μl of nuclease-free water to make up the reaction volume. Thermal cycling conditions were 1 cycle of 94°C for 4 min, 35 cycles of 94°C for 1 min, 57°C for 1 min, 72°C for 1 min and a final extension for 10 min at 72°C. Amplified products were confirmed on a 1% Agarose gel stained with 4.6 μl SYBR safe DNA stain (Invitrogen, Carlsbad, California, USA), and bands at 441 bp were observed in an Ultra Violet gel viewer. The PCR products were enzymatically purified using ExoSAP IT (Applied Biosystems, Foster City, California, USA). Purification conditions were 37°c for 15 min followed by a second incubation at 80°c for 15 min and a final cooling step at 4°C for 5 min.

Results

A total 24,549 records were reviewed. Of these, 167 (0.7%) NTMs were isolated (Kamau, 2023). The highest isolation was among individual aged 35-44 years, (46/167, 27.5%). Males comprised 74.2% (124). The mean age (SD) was 42(16) years. The NTM were isolated in 65% (31/47) of the counties; Most isolated NTM samples came from Nairobi County at 12.6% (21/167), then Mombasa 10.8% (18/167), and Kilifi and Meru counties at 7.8% (13/167). Most NTM were isolated from previously treated patients 63.5%(106/167), drug-resistant follow-up patients 26.9% (45/167) and New patients 9.6%(16/167) [Table 1]. Coinfection with NTM and HIV was at 27.5% (46/167).

Table 1. Sociodemographic characteristics of patients with nontuberculous mycobacteria, Kenya 2018-2019.

VariablesParticipants (%)nχ2, p
Age (years)
≤143.0(5)11.31, 0.334
15-247.8(13)
25-3422.8(38)
35-4427.5(46)
45-5418.0(30)
55-6412.6(21)
≥658.4(14)
Sub total100(167)
Gender
Male74.2(124)
Female25.8(43)
Sub total100(167)
Hiv status
Negative56.3(94)69.67, 0.184
Positive27.5(46)
Not reported16.2(27)
Sub total100(167)
Type of patient
Previously treated63.5(106)80.87, 0.744
MDR/RR26.9(45)
New9.6(16)
Sub total100(167)
Counties
Nairobi12.6(21)33.56, 0.299
Mombasa10.8(18)
Kilifi7.8(13)
Meru7.8(13)
Murang'a6.0(10)
Machakos4.8(8)
Kitui4.8(8)
Turkana4.2(7)
West Pokot4.2(7)
Kirinyaga3.0(5)
Nakuru3.0(5)
Kisumu3.0(5)
Makueni3.0(5)
Laikipia2.4(4)
Taita Taveta2.4(4)
Kakamega2.4(4)
Tharaka Nithi2.4(4)
Nyeri1.8(3)
Kajiado1.8(3)
Siaya1.8(3)
Embu1.2(2)
Nyandarua1.2(2)
Kiambu1.2(2)
Bomet1.2(2)
Nandi1.2(2)
Busia1.2(2)
Garissa0.6(1)
Narok0.6(1)
Baringo0.6(1)
Migori0.6(1)
Trans Nzoia0.6(1)
Sub total100(167)

A total of eleven NTM species were identified, with frequent ones being Mycobacterium intracellulare at 35.3% (59/167), M. fortuitum at 26.3% (44/167), and M. scrofulaceum at 10.2% (17/167). Majority of NTM had a Smear outcome of No AFB seen [59.3%(99)], Smear 1+ [11.4%(19)], and smear 2+ [10.2%(17)] [Table 2].

Table 2. Types of non-tuberculous species isolated microscopy concentrate outcome, Kenya 2018-2019.

NTM speciesNo of species isolated %, n
M.intracellulare35.3(59)
M.fortuitum26.3(44)
M.scrofulaceum10.2(17)
M.kansasii9.6(16)
M.simiae4.2(7)
M.gordonae4.2(7)
M.avium3.0(5)
M.szulgai3.0(5)
M.abscessus3.0(5)
M.asiaticum0.6(1)
M.lentiflavum0.6(1)
Sub total100(167)
Smear concentrateSmear Outcome %, n
NEG59.3(99)
1+11.4(19)
2+10.2(17)
3+9.6(16)
SCANTY29.6(16)
Sub total100(167)

Table 3. Slow and Rapid growing NTM.

No of species %, n
Slow growing NTM
M.abscessus5.9(5)
M.avium5.9(5)
M.intracellulare69.4(59)
M.kansasii18.8(16)
Sub total50.9(85)
Rapid growing NTM
M.asiaticum1.2(1)
M.fortuitum53.7(44)
M.gordonae8.5(7)
M.lentiflavum1.2(1)
M.scrofulaceum20.7(17)
M.simiae8.5(7)
M.szulgai6.1(5)
Sub total49.1(82)

Table 4. MAC distribution in Counties.

CountyNo of species %, n
Nairobi12.5(8)
Kilifi9.4(6)
Kisumu7.8(5)
Kitui7.8(5)
Machakos7.8(5)
Mombasa7.8(5)
Murang'a7.8(5)
Turkana6.3(4)
West Pokot6.3(4)
Meru4.7(3)
Kakamega3.1(2)
Laikipia3.1(2)
Makueni3.1(2)
Siaya3.1(2)
Busia1.6(1)
Embu1.6(1)
Kajiado1.6(1)
Nakuru1.6(1)
Nyandarua1.6(1)
Tharaka Nithi1.6(1)
Sub total100(64)

Discussion

Our study found that the prevalence of NTM was low AT [0.7%(167/24,549)] and most of the cases were males which was similar to study done by (Fatima & Nm, 2019) on prevalence of Nontuberculous Mycobacterial infection in Non-HIV subjects. The MAC complex is considered to be the most prevalent globally accounting for 86% (Nishiuchi et al., 2017). These findings are consistent with our study that isolated MAC species M.intracellulare [35.3 % (59/167), M.fortuitum 26.3% (44/167) M. scrofulaceum 10.2% (17/167), M.kansasii 9.6% (16/167)] [Table 2]. MAC species are frequently isolated in different environmental sources like water and soil and there is frequent contact with this sources thus increasing its infection to human (van Ingen et al., 2009). Similar findings from other countries have described isolation of MAC species (Namkoong et al., 2016; Nishiuchi et al., 2017). Similar finding found out that M. intracellulare was most prevalent (Epola Dibamba Ndanga et al., 2022). However, MAC was not reported as predominant in other settings i.e. South Pacifica where M.fortuitum complex fewer cases were isolated; in India M.fortuitum was predominant and MAC was not detected. The high infectivity rate of MAC species may be linked to their apparent abundance and distribution in many environmental sources such as water and soil, which increases the ease of dissemination and infection to people. MAC has been strongly linked to NTM Pulmonary Disease (NTMPD); nevertheless, it is unknown how its infectivity connects to NTMPD (Mwangi et al., 2021, 2022).

In our findings persons within the age group (35-44 years) were most affected. More males were affected suggesting that women could be having a protective effect due to the hormonal variation which triggers a response and clears the bacterial infection (Namkoong et al., 2016; Ji et al., 2020).

Pulmonary NTM were mostly found in patients who were previously treated for TB Most of the cases were HIV negative which was inconsistent with what has been reported previously (Stepanyan et al., 2019). In people with HIV/AIDS, NTM infections can occur in various parts of the body, including the lungs, lymph nodes, and skin. These infections can be severe and difficult to treat, especially if the immune system is severely compromised.

Most NTM were isolated from of counties, leading county being Nairobi County with [12.6 %(21/167)], followed by Mombasa County and Kilifi and Meru County. These findings may be inconclusive on factors influencing the geographical distribution of NTM in the different geographical landscapes in Kenya, a more comprehensive study capturing both human and environmental particulars is required for a better understanding of environmental NTM species distribution. Differences in specific NTM species predominance in various environments may in part influence the frequency of pulmonary NTM disease in each geographical location.

The presence of NTM among the presumptive cases poses a public health challenge and which potentially complicates TB diagnosis and management. The Division of National TB, Leprosy and Lung Diseases Program (DNTLD-P) should put NTM in planning the prevention and management of tuberculosis control, these findings are similar to a study done in Gabon (Epola Dibamba Ndanga et al., 2022).

Conclusion

Our study characterized the diversity of NTM and identified 11 different species. MAC was the most prevalent followed by M. fortuitum complex and M. scrofulaceum species. Slow growing NTM were majority 50.9% (85/167) while rapid growing NTM were 49.1% (82/167). Most of the previously treated patients had NTM, Males were the majority within (35-44) years.

Limitation of the study

The study lacked clinical data to correlate the NTM isolation. Despite the limitations the study was able to characterize the diversity of NTM.

Data availability

Underlying data

figshare: Non-Tuberculous Mycobacterium isolations from Tuberculosis presumptive cases at the National Tuberculosis Reference Laboratory Kenya, 2018 –2019. https://doi.org/10.6084/m9.figshare.23498426.v1 (Kamau, 2023).

Data are available under the terms of the Creative Commons Attribution 4.0 International license (CC-BY 4.0).

Acknowledgments

The authors wish to express their gratitude to all participants who took part in this study, grateful to National Public Health Laboratories- Kenya for granting the access to NTRL and conduct the research and appreciate the assistance accorded by the staffs in their technical support in preparation and analysis of samples in this study.

References

  •  Aksamit TR, Philley JV, Griffith DE: Nontuberculous mycobacterial (NTM) lung disease: The top ten essentials. Respir. Med. 2014; 108(3): 417–425. PubMed Abstract | Publisher Full Text
  •  Daley CL, Iaccarino JM, Lange C, et al.: Treatment of Nontuberculous Mycobacterial Pulmonary Disease: An Official ATS/ERS/ESCMID/IDSA Clinical Practice Guideline. Clin. Infect. Dis. 2020; 71(4): e1–e36. PubMed Abstract | Publisher Full Text | Free Full Text
  •  Duarte RSRS, Lourenço MCSMCS, Fonseca LdSLdS, et al.: Epidemic of Postsurgical Infections Caused by Mycobacterium massiliense. J. Clin. Microbiol. 2009; 47(7): 2149–2155. PubMed Abstract | Publisher Full Text | Free Full Text
  •  Epola Dibamba Ndanga M, Achimi Agbo Abdul JBP, Edoa JR, et al.: Non-tuberculous mycobacteria isolation from presumptive tuberculosis patients in Lambaréné, Gabon. Tropical Med. Int. Health. 2022; 27(4): 438–444. PubMed Abstract | Publisher Full Text
  •  Fatima and Nm—2019—Prevalence of nontuberculous Mycobacterial infecti.pdf: n.d. Retrieved May 16, 2023. Reference Source
  •  Fatima S, Nm A: Prevalence of nontuberculous Mycobacterial infection in Non-HIV subjects of clinically presumed tuberculosis at a tertiary care center, Hyderabad. IP International Journal of Medical Microbiology and Tropical Diseases. 2019; 5(2): 116–122. Publisher Full Text
  •  Ferreira RMC, Saad MHF, da Silva MG , et al.: Non-tuberculous mycobacteria I: One year clinical isolates identification in Tertiary Hospital Aids Reference Center, Rio de Janeiro, Brazil, in pre highly active antiretroviral therapy era. Mem. Inst. Oswaldo Cruz. 2002; 97: 725–729. PubMed Abstract | Publisher Full Text
  •  Hoefsloot W, van Ingen J , Andrejak C, et al.: The geographic diversity of nontuberculous mycobacteria isolated from pulmonary samples: An NTM-NET collaborative study. Eur. Respir. J. 2013; 42(6): 1604–1613. PubMed Abstract | Publisher Full Text
  •  Integrated Guideline: n.d.. 467.
  •  Jacqueline L, Christine B, Ngayo MO, et al.: Infection rates and correlates of non-tuberculous mycobacteria among tuberculosis retreatment cases in Kenya. Prime Journal of Social Science (PJSS). 2015; 1128–1134.
  •  Ji S, Xu W, Sun J, et al.: Retrospective analysis of patients with non-tuberculous mycobacteria from a primary hospital in Southeast China. Sci. Rep. 2020; 10(1): 1060. PubMed Abstract | Publisher Full Text | Free Full Text
  •  Kamau G: Non-Tuberculous Mycobacterium isolations from Tuberculosis presumptive cases at the National Tuberculosis Reference Laboratory Kenya, 2018 –2019. [Dataset]. figshare. 2023. Publisher Full Text
  •  Mertaniasih NM, Kusumaningrum D, Koendhori EB, et al.: Nontuberculous mycobacterial species and Mycobacterium tuberculosis complex coinfection in patients with pulmonary tuberculosis in Dr. Soetomo Hospital, Surabaya, Indonesia. Int. J. Mycobacteriol. 2017; 6(1): 9–13. PubMed Abstract | Publisher Full Text
  •  Morimoto K, Iwai K, Uchimura K, et al.: A Steady Increase in Nontuberculous Mycobacteriosis Mortality and Estimated Prevalence in Japan. Ann. Am. Thorac. Soc. 2014; 11(1): 1–8. PubMed Abstract | Publisher Full Text
  •  Mwangi ZM, Mukiri N, Onyambu FG, et al.: Genetic Diversity of Non-Tuberculous Mycobacteria among Symptomatic TB negative Patients in Kenya. bioRxiv. 2021; p. 2021.10.28.465104. Publisher Full Text
  •  Mwangi ZM, Mukiri N, Onyambu FG, et al.: Genetic Diversity of Nontuberculous Mycobacteria among Symptomatic Tuberculosis Negative Patients in Kenya. Int. J. Mycobacteriol. 2022; 11(1): 60. Publisher Full Text
  •  Namkoong H, Kurashima A, Morimoto K, et al.: Epidemiology of Pulmonary Nontuberculous Mycobacterial Disease, Japan. Emerg. Infect. Dis. 2016; 22(6): 1116–1117. PubMed Abstract | Publisher Full Text | Free Full Text
  •  Ngayo M, Ngayo M, Mutua D: Infection rates and correlates of Non-Tuberculous Mycobacteria among Tuberculosis retreatment cases In Kenya. Prime J. Soc. Sci. 2015; Vol. 4(7): pp. 1128–1134. 2315-5051.
  •  Nishiuchi Y, Iwamoto T, Maruyama F: Infection Sources of a Common Non-tuberculous Mycobacterial Pathogen, Mycobacterium avium Complex. Front. Med. 2017; 4. PubMed Abstract | Publisher Full Text | Free Full Text
  •  Stepanyan IE, Zaytseva AS, Bagdasaryan TR, et al.: Nontuberculous mycobacterial co-infection in HIV-negative patients with pulmonary tuberculosis. Eur. Respir. J. 2019; 54(suppl 63). Publisher Full Text
  •  van Ingen J , Boeree MJ, Dekhuijzen PNR, et al.: Environmental sources of rapid growing nontuberculous mycobacteria causing disease in humans. Clin. Microbiol. Infect. 2009; 15(10): 888–893. PubMed Abstract | Publisher Full Text

Comments on this article Comments (0)

Version 2
VERSION 2 PUBLISHED 04 Sep 2023
Comment
Author details Author details
Competing interests
Grant information
Article Versions (2)
Copyright
Download
 
Export To
metrics
Views Downloads
F1000Research - -
PubMed Central
Data from PMC are received and updated monthly.
 - -
Citations
SEE MORE DETAILS
CITE
how to cite this article
Kamau G, Mwangi Z, Bargul J et al. Non-tuberculous mycobacterium isolations from tuberculosis presumptive cases at the National Tuberculosis Reference Laboratory Kenya, 2018–2019 [version 2; peer review: 1 approved, 2 not approved]. F1000Research 2024, 12:1104 (https://doi.org/10.12688/f1000research.135106.2)
NOTE: If applicable, it is important to ensure the information in square brackets after the title is included in all citations of this article.
track
receive updates on this article
Track an article to receive email alerts on any updates to this article.

Open Peer Review

Current Reviewer Status: ?
Key to Reviewer Statuses VIEW
ApprovedThe paper is scientifically sound in its current form and only minor, if any, improvements are suggested
Approved with reservations A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit.
Not approvedFundamental flaws in the paper seriously undermine the findings and conclusions
Version 2
VERSION 2
PUBLISHED 09 Jul 2024
Revised
Views
7
Cite
Reviewer Report 30 Aug 2024
Yukiko Nishiuchi, Hiroshima University, Higashi-Hiroshima, Japan 
Not Approved
VIEWS 7
https://doi.org/10.5256/f1000research.168666.r312892
Title: Non-tuberculous mycobacterium isolations from tuberculosis presumptive cases at the National Tuberculosis Reference Laboratory Kenya, 2018â2019
 
Review comments
As the authors described, data on mycobacterial species in pulmonary infections are scarce and misdiagnosis is common in ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Nishiuchi Y. Reviewer Report For: Non-tuberculous mycobacterium isolations from tuberculosis presumptive cases at the National Tuberculosis Reference Laboratory Kenya, 2018–2019 [version 2; peer review: 1 approved, 2 not approved]. F1000Research 2024, 12:1104 (https://doi.org/10.5256/f1000research.168666.r312892)
The direct URL for this report is:
https://f1000research.com/articles/12-1104/v2#referee-response-312892
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
Report a concern
Views
7
Cite
Reviewer Report 11 Jul 2024
Abiona Oluwadamilola Odeyemi, College of Health Sciences, Department of Medicine, Osun State University, Osogbo, Osun, Nigeria 
Approved
VIEWS 7
https://doi.org/10.5256/f1000research.168666.r300687
I have no ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Odeyemi AO. Reviewer Report For: Non-tuberculous mycobacterium isolations from tuberculosis presumptive cases at the National Tuberculosis Reference Laboratory Kenya, 2018–2019 [version 2; peer review: 1 approved, 2 not approved]. F1000Research 2024, 12:1104 (https://doi.org/10.5256/f1000research.168666.r300687)
The direct URL for this report is:
https://f1000research.com/articles/12-1104/v2#referee-response-300687
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
Report a concern
Version 1
VERSION 1
PUBLISHED 04 Sep 2023
Views
8
Cite
Reviewer Report 06 Jun 2024
Abiona Oluwadamilola Odeyemi, College of Health Sciences, Department of Medicine, Osun State University, Osogbo, Osun, Nigeria 
Approved
VIEWS 8
https://doi.org/10.5256/f1000research.148209.r276826
Overall, it was a good research.
It was technically sound and exhibited originality.
It was also well structured and it gave adequate detail as to how the organisms were isolated.
I would have attached the PDF file ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Odeyemi AO. Reviewer Report For: Non-tuberculous mycobacterium isolations from tuberculosis presumptive cases at the National Tuberculosis Reference Laboratory Kenya, 2018–2019 [version 2; peer review: 1 approved, 2 not approved]. F1000Research 2024, 12:1104 (https://doi.org/10.5256/f1000research.148209.r276826)
The direct URL for this report is:
https://f1000research.com/articles/12-1104/v1#referee-response-276826
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
Report a concern
Views
17
Cite
Reviewer Report 20 Mar 2024
Durga Shankar Meena, All India Institute of Medical Sciences, Jodhpur, India 
Not Approved
VIEWS 17
https://doi.org/10.5256/f1000research.148209.r246327
1. In 'abstract' section, patient with negative AFB and MPT 64 ag were analysed? What about AFB +, gene Xpert negative patients? Many of such patients might belonged to NTM group.

2. Line "Nairobi had 12.6% (21/167), ... Continue reading
CITE
CITE
HOW TO CITE THIS REPORT
Meena DS. Reviewer Report For: Non-tuberculous mycobacterium isolations from tuberculosis presumptive cases at the National Tuberculosis Reference Laboratory Kenya, 2018–2019 [version 2; peer review: 1 approved, 2 not approved]. F1000Research 2024, 12:1104 (https://doi.org/10.5256/f1000research.148209.r246327)
The direct URL for this report is:
https://f1000research.com/articles/12-1104/v1#referee-response-246327
NOTE: it is important to ensure the information in square brackets after the title is included in all citations of this article.
Report a concern
  • Author Response 09 Jul 2024
    George Kamau, Department of Preventive and Promotive Health (DPPH), Field Epidemiology Laboratory Training Program (FELTP), Nairobi, Kenya
    09 Jul 2024
    Author Response
    I addressed all the reviews and recommendations made and sent a revised version
    Competing Interests: I do not have any competing interests
    Report a concern
  • Respond or Comment
COMMENTS ON THIS REPORT
  • Author Response 09 Jul 2024
    George Kamau, Department of Preventive and Promotive Health (DPPH), Field Epidemiology Laboratory Training Program (FELTP), Nairobi, Kenya
    09 Jul 2024
    Author Response
    I addressed all the reviews and recommendations made and sent a revised version
    Competing Interests: I do not have any competing interests
    Report a concern

Comments on this article Comments (0)

Version 2
VERSION 2 PUBLISHED 04 Sep 2023
Comment

Open Peer Review

Reviewer Status

Alongside their report, reviewers assign a status to the article:

Approved
The paper is scientifically sound in its current form and only minor, if any, improvements are suggested
Approved with reservations
A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit.
Not approved
Fundamental flaws in the paper seriously undermine the findings and conclusions

Reviewer Reports

Invited Reviewers
1 2 3
Version 2
(revision)
 09 Jul 24 		read read
Version 1
04 Sep 23 		read read
  1. Durga Shankar Meena, All India Institute of Medical Sciences, Jodhpur, India
  2. Abiona Oluwadamilola Odeyemi, Osun State University, Osogbo, Nigeria
  3. Yukiko Nishiuchi, Hiroshima University, Higashi-Hiroshima, Japan

Comments on this article

All Comments(0)

Add a comment
Sign up for content alerts

Browse by related subjects

    keyboard_arrow_left Back to all reports
    keyboard_arrow_left Back to all reports
    keyboard_arrow_left Back to all reports
    keyboard_arrow_left Back to all reports
    Alongside their report, reviewers assign a status to the article:
    Approved - the paper is scientifically sound in its current form and only minor, if any, improvements are suggested
    Approved with reservations - A number of small changes, sometimes more significant revisions are required to address specific details and improve the papers academic merit.
    Not approved - fundamental flaws in the paper seriously undermine the findings and conclusions
    Sign In
    If you've forgotten your password, please enter your email address below and we'll send you instructions on how to reset your password.

    The email address should be the one you originally registered with F1000.
    Email address not valid, please try again

    You registered with F1000 via Google, so we cannot reset your password.

    To sign in, please click here.

    If you still need help with your Google account password, please click here.

    You registered with F1000 via Facebook, so we cannot reset your password.

    To sign in, please click here.

    If you still need help with your Facebook account password, please click here.

    Code not correct, please try again
    Email us for further assistance.
    Server error, please try again.