Paul R Klatser

• PhD
• Head of Department at Royal Tropical Institute

Background: In 2011 the Stepwise Laboratory Quality Improvement Process Towards Accreditation (SLIPTA) was launched, aimed at strengthening the quality and competence of African clinical, public health and reference laboratories. We reviewed the first version of the SLIPTA checklist in 2011. The continued development and publication of a new versio...

Current HIV policies in Tanzania have adopted the three long-term impact results of zero new infections, zero HIV deaths and zero stigma and discrimination. Strategies to reach these results include scaling-up HIV Testing and Counselling (HTC); Preventing Mother-To-Child Transmission (PMTCT); and strengthening Care and Treatment Clinic (CTC) servic...

Diabetes prevalence in Tanzania was estimated at 9.1% in 2012 among adults aged 24-65 years - higher than the HIV prevalence in the general population at that time. Health systems in lower- and middle-income countries are not designed for chronic health care, yet the rising burden of non-communicable diseases such as diabetes demands chronic care s...

Background: The high prevalence of chronic diseases in Tanzania is putting a strain on the already stretched health care services, patients and their families. This study sought to find out how health care for diabetes and HIV is perceived, practiced and experienced by patients and family caregivers, to inform strategies to improve continuity of c...

The inability to detect all individuals with active tuberculosis has led to a growing interest in new approaches to improve case detection. Policy makers and program staff face important challenges measuring effectiveness of newly introduced interventions and reviewing feasibility of scaling-up successful approaches. While robust research will cont...

Background Multiplex ligation-dependent probe amplification (MLPA) is a powerful tool to identify genomic polymorphisms. We have previously developed a single nucleotide polymorphism (SNP) and large sequence polymorphisms (LSP)-based MLPA assay using a read out on a liquid bead array to screen for 47 genetic markers in the Mycobacterium tuberculosi...

Background: Most low-and middle-income countries are facing a rise of the burden of non-communicable diseases (NCDs) alongside the persistent burden of infectious diseases. This narrative review aims to provide an inventory of how the existing policy environment, health system, and communities are addressing the NCDs situation in Tanzania and ident...

Background Most low- and middle- income countries are facing a rise of the burden of non-communicable diseases (NCDs) alongside the persistent burden of infectious diseases. This narrative review aims to provide an inventory of how the existing policy environment, health system, and communities are addressing the NCDs situation in Tanzania and iden...

STARD checklist for reporting studies of diagnostic accuracy. (DOC)

Predictive value of indeterminate and negative test results. (TIF)

Availability of the three RDTs throughout the years. (TIF)

Results of the three RDTs. The results are stratified for: 1st sample and follow up (FU) sample, DPO (0–4, 5–10, 11–20, >20), probable infecting serogroup (Icterohaemorrhagiae, Grippotyphosa, other, non-classifiable), years. (TIF)

Diagnosis of leptospirosis by the microscopic agglutination test (MAT) or by culture is confined to specialized laboratories. Although ELISA techniques are more common, they still require laboratory facilities. Rapid Diagnostic Tests (RDTs) can be used for easy point-of-care diagnosis. This study aims to evaluate the diagnostic performance of the R...

Recently we proposed exploring the potential of treatment stimulated testing as diagnostic method for tuberculosis (TB). An infection controlled placebo controlled mouse study was performed to investigate whether serum cytokine levels changed measurably during the early phase of TB chemotherapy. Serum was collected prior to and during the first 3 w...

Cytokine levels measured from all serum samples. All cytokine levels measured in pg/ml for are shown. Empty cells indicate a specific marker was not measured in that sample. (JPG)

Successful integration of new diagnostics in national tuberculosis (TB) control programs, also called 'retooling', is highly dependent on operational aspects related to test availability, accessibility and affordability. This survey aimed to find out whether recommendations to use new diagnostics lead to successful retooling in high TB endemic coun...

The population structure of Mycobacterium tuberculosis is typically clonal therefore genotypic lineages can be unequivocally identified by characteristic markers such as mutations or genomic deletions. In addition, drug resistance is mainly mediated by mutations. These issues make multiplexed detection of selected mutations potentially a very power...

Table shows the drug resistance profiles and species identification of all strains analysed in this study as determined by various methods. (XLSX)

Table shows marker-specific MFI values measured by the bead-based MLPA of 88 mycobacterial and one non-mycobacterial species. (XLSX)

Summary table of Figure 3 . (XLSX)

Letter to the Editor about the Global Laboratory Initiative (GLI) tool.

Mycobacterium cultures, from patients suspected of tuberculosis or nontuberculous mycobacteria (NTM) infection, need to be identified. It is most critical to identify cultures belonging to the Mycobacterium tuberculosis complex, but also important to recognize clinically irrelevant or important NTM to allow appropriate patient management. Identific...

Both the probability of a mutation occurring and the ability of the mutant to persist will influence the distribution of mutants that arise in a population. We studied the interaction of these factors for the in vitro selection of rifampicin (RIF)-resistant mutants of Mycobacterium tuberculosis. We characterised two series of spontaneous RIF-resist...

Background The variety and number of laboratory quality standards, guidelines and regulations (hereafter: quality documents) makes it difficult to choose the most suitable one for establishing and maintaining a laboratory quality management system. Objectives There is a need to compare the characteristics, suitability and applicability of quality...

Dengue has become a global public health problem and a sensitive diagnostic test for early phase detection can be life saving. An internally controlled, generic real-time PCR was developed and validated by testing serial dilutions of a DENV positive control RNA in the presence of a fixed amount of IC with results showing a good linearity (R(2) = 0....

Objective: Clinical laboratories in low- and middle-income countries (LMIC) need fundamental improvement because quality laboratory services are essential for the decision-making capacity of clinicians, health workers and public health authorities. To this end, a tiered accreditation scheme Stepwise Laboratory Improvement Process Towards Accredita...

An accurate, simple, and direct test for tuberculosis (TB) has been a priority for many years, but to date no such test has become available. Easily detectable sensitive and specific biomarkers are elusive and may remain so. In parallel to the essential extensive efforts in biomarker discovery performed in this field, we suggest it is also worthwhi...

This article summarizes the deliberations and recommendations of two workshops held in Bamako and Lisbon in 2008 and 2010, respectively, where about 50 researchers from sub-Saharan Africa discussed their views on research and capacity requirements for the control of neglected tropical diseases (NTDs). The workshops were organized under the framewor...

A delay is evident between the development of new policies on TB diagnostics and their implementation at country level. The Stop TB Partnership would benefit from information from national TB program (NTP) managers on progress towards implementation of new recommendations as well as the opportunities and challenges encountered in the process. To so...

Even with the advent of nucleic acid (NA) amplification technologies the culture of mycobacteria for diagnostic and other applications remains of critical importance. Notably microscopic observed drug susceptibility testing (MODS), as opposed to traditional culture on solid media or automated liquid culture, has shown potential to both speed up and...

Diagnostic tests are generally used in situations with similar pre-test probability of disease to where they were developed. When these tests are applied in situations with very different pre-test probabilities of disease, it is informative to model the likely implications of known characteristics of test performance in the new situation. This is t...

The diagnosis of extra-pulmonary tuberculosis (EPTB) by conventional methods such as culture and microscopy has low sensitivity and requires an invasive procedure. A simple rapid serological test would be of great value. Six antigens (ESAT-6, Ag85A, TB10.4, Rv3881c, lipoarabinomannan (LAM) and Ara6-BSA) were tested in an ELISA to detect antigen spe...

Tuberculosis is one of the most prominent health problems in the world, causing 1.75 million deaths each year. Rapid clinical diagnosis is important in patients who have co-morbidities such as Human Immunodeficiency Virus (HIV) infection. Direct microscopy has low sensitivity and culture takes 3 to 6 weeks 123. Therefore, new tools for TB diagnosis...

Attempts to improve the diagnosis of tuberculosis (TB) in high-burden countries has resulted in significant funding and initiatives to change the method of diagnosis of TB from light microscopy supplemented with X-ray to a sophisticated diagnostic algorithm based on the latest technological innovations. Such activities are overdue and should be wel...

The high prevalence of isoniazid-resistant Mycobacterium tuberculosis is often explained by a high mutation rate for this trait, although detailed information to support this theory is absent. We studied the development of isoniazid resistance in vitro, making use of a laboratory strain of M. tuberculosis. Spontaneous isoniazid-resistant mutants we...

In Ethiopia, little has been done to assess how Mycobacterium bovis has contributed to human tuberculosis, though the population routinely consumes unpasteurized milk and raw meat. The aim of this study was to determine the proportion of M. tuberculosis and M. bovis as etiological agents of tuberculous lymphadenitis (TBLN). Patients with lymphadeno...

The adaptation and use of a Bloodhound® ST214 electronic nose to rapidly detect TB in sputum samples has been discussed in the past, with some promising results being obtained in 2007. Some of the specific VOC’s associated with Mycobacteria tuberculosis organisms are now being discovered and a paper was published in 2008, but the method of predicti...

A tuberculosis (TB) research laboratory in the Netherlands. The concentration of Mycobacterium tuberculosis cells from sputum is almost universally performed by centrifugation after chemical liquefaction. These methods are thus dependent on the effective sedimentation of mycobacterial cells, and the buoyant density of these cells relative to sputum...

Butajira, Southern Ethiopia. To compare the diagnostic capacity of the clinical criteria for tuberculous lymphadenitis (TBLN) with histological and/or culture results and to assess the association of human immunodeficiency virus (HIV) with tuberculosis (TB) lymphadenitis. Patients (n=171) were included in the study from October 2005 until July 2006...

We have developed a multiplex assay, based on multiplex ligation-dependent probe amplification (MLPA), that allows simultaneous detection of multiple drug resistance mutations and genotype-specific mutations at any location in the Mycobacterium tuberculosis genome. The assay was validated on a reference panel of well-characterized strains, and the...

Leprosy control programs would benefit expressively from an easy method to estimate disease prevalence and to assess the effect of leprosy control measures on disease prevalence. Determination of the seroprevalence of antibodies to PGL-I through school children surveys might be a useful indicator of leprosy prevalence at the district level. To inve...

Leprosy control programs would benefit expressively from an easy method to estimate disease prevalence and to assess the effect of leprosy control measures on disease prevalence. Determination of the seroprevalence of antibodies to PGL-I through school children surveys might be a useful indicator of leprosy prevalence at the district level. To inve...

In Mycobacterium tuberculosis (MTB), rifampicin resistance is almost invariably due to mutations in the rpoB gene, whose function is critical for cell viability. Most of these mutations, at least initially, impair the fitness of the bacteria but confer a selective advantage when antibiotic pressure is exerted. Subsequent adaptation may be critical...

To evaluate the use of the ML Flow test as an additional, serological, tool for the classification of new leprosy patients. In Brazil, Nepal and Nigeria, 2632 leprosy patients were classified by three : (1) as multibacillary (MB) or paucibacillary (PB) according to the number of skin lesions (WHO classification), (2) by slit skin smear examination,...

To study patient determinants that may affect completion of the diagnostic process in tuberculosis control, highlighting the role of counselling. Cross-sectional study. TB patients. Rhodes Chest Clinic, Nairobi, City Council. Ninety five percent of the suspects delivered three sputum samples but only 27% consented to a HIV test; several determinant...

We describe the simple adaptation of a standard fluorescent microscope for illumination using a 'Royal Blue' Luxeon light emitting diode (LED) and demonstrate that this form of illumination is suitable for the detection of auramine O stained Mycobacterium spp. The low cost, low power consumption, safety and reliability of LEDs makes them attractive...

Ziehl-Neelsen (ZN) staining for the diagnosis of tuberculosis (TB) is time-consuming and operator dependent and lacks sensitivity. A new method is urgently needed. We investigated the potential of an electronic nose (EN) (gas sensor array) comprising 14 conducting polymers to detect different Mycobacterium spp. and Pseudomonas aeruginosa in the hea...

We identified risk factors associated with increased yearly incidence rates of leprosy in five island populations. Age, sex, household size and Mycobacterium leprae-specific antibodies as well as contact factors were studied. Of 94 index patients (patients diagnosed in 2000), 43 (46%) were classified as multibacillary (MB), 17 (19%) were seropositi...

Early detection of Mycobacterium leprae infection is considered an important component of strategies aiming at reducing transmission of infection, but currently available diagnostic tools often lack sufficient sensitivity and specificity to reach this goal. Recent comparative genomics have revealed the presence of 165 M. leprae genes with no homolo...

Production of IFN-gamma guarantees helpful T cell-mediated immunity against Mycobacterium tuberculosis infection. We have evaluated the in vitro immune responses to M. tuberculosis antigens using IFN-gamma production among 43 Brazilian tuberculosis (TB) patients prior to and after specific treatment, and 18 community controls. Peripheral blood mono...

Laboratory services, particularly in large sub-Saharan cities, are overstretched, and it is becoming difficult both for patients and health staff to adhere to the diagnostic procedures for tuberculosis. Alternative techniques would be welcome. The polymerase chain reaction (PCR) has the potential to be cost-effective. We compared the cost-effective...

Multidrug-resistant tuberculosis (MDR-TB) is known as having a poor prognosis with a weak response to therapy and very high death rates. The aim of this work was to assess the immune response to the RD1-encoded antigen ESAT-6 of Mycobacterium tuberculosis in MDR-TB patients and compare to non-resistant (NR) TB patients and healthy controls (HC). Ev...

Mutations in a small region of the rpoB gene are responsible for most rifamycin resistance in Mycobacterium tuberculosis. In this study we have sequentially generated resistant strains to first rifampicin and then rifabutin. Portions of the rpoB gene were sequenced from 131 randomly selected mutants. Second round selection resulted in a changed fre...

An intervention study was implemented on five Indonesian islands highly endemic for leprosy to determine whether rifampicin can be used as chemoprophylaxis to prevent leprosy. The population was actively screened before the intervention and subsequently once a year for three years. In the control group, no chemoprophylaxis was given. In the contact...

City Council Chest Clinic, Nairobi, Kenya. To determine to what extent the performance of smear microscopy is responsible for sex differences in notification rates. Three sputum samples from TB suspects were subjected to smear microscopy with Ziehl-Neelsen (ZN) and auramine (FM) staining. Lowenstein-Jensen culture was used as the gold standard. Of...

The objective of this study was to establish 1) the performance of chest X-ray (CXR) in all suspects of tuberculosis (TB), as well as smear-negative TB suspects and 2) to compare the cost-effectiveness of the routine diagnostic pathway using Ziehl-Neelsen (ZN) sputum microscopy followed by CXR if case of negative sputum result (ZN followed by CXR)...

It is generally accepted that genetic factors play a role in susceptibility to both leprosy per se and leprosy type, but only few studies have tempted to quantify this. Estimating the contribution of genetic factors to clustering of leprosy within families is difficult since these persons often share the same environment. The first aim of this stud...

The direct detection of mRNAs from bacterial cultures on a DNA array without amplification and labelling would greatly extend the range of applications suitable for microarray analysis. Here we describe the direct detection of 23S rRNA and seven mRNA species from total Staphylococcus aureus RNA prepared using commercially available RNA purification...

Not every leprosy patient is equally effective in transmitting Mycobacterium leprae. We studied the spatial distribution of infection (using seropositivity as a marker) in the population to identify which disease characteristics of leprosy patients are important in transmission. Clinical data and blood samples for anti-M. leprae ELISA were collecte...

The use of volatile production patterns produced by Mycobacterium tuberculosis and associated bacterial infections from sputum samples were examined in vitro and in situ using an electronic nose based on a 14 sensor conducting polymer array. In vitro, it was possible to successfully discriminate between M. tuberculosis (TB) and control media, and b...

The current strategy for leprosy control using case detection and treatment has greatly reduced the prevalence of leprosy, but has had no demonstrable effect on interrupting transmission. Three leprosy endemic communities in India were recruited, examined, and followed up sequentially over 2 yrs using nasal swabs and saliva collections. The nasal s...

Although the prevalence of leprosy has declined over the years, there is no evidence that incidence rates are falling. A method of early detection of those people prone to develop the most infectious form of leprosy would contribute to breaking the chain of transmission. Prophylactic treatment of serologically identified high-risk contacts of incid...

Direct smear examination with Ziehl-Neelsen (ZN) staining for the diagnosis of tuberculosis (TB) as employed in most low-income countries is cheap and easy to use, but its low sensitivity is a major drawback. The low specificity of chest X-rays, used for the diagnosis of smear-negative TB, risks high levels of overdiagnosis. Major advances in molec...

Nairobi City Council Chest Clinic, Kenya. To establish the efficiency, costs and cost-effectiveness of six diagnostic strategies using Ziehl-Neelsen (ZN) and fluorescence microscopy (FM). A cross-sectional study of 1398 TB suspects attending a specialised chest clinic in Nairobi subjected to three sputum examinations by ZN and FM. Lowenstein-Jensen...

The number of registered leprosy patients world-wide has decreased dramatically after extensive application of WHO recommended Multiple Drug Therapy (MDT). The annual number of new cases has, however, been almost unchanged in several populations, indicating that the infection is still present at community level. Nasal carriage of Mycobacterium lepr...

The interruption of leprosy transmission is one of the main challenges for leprosy control programs since no consistent evidence exists that transmission has been reduced after the introduction of multidrug therapy. Sources of infection are primarily people with high loads of bacteria with or without clinical signs of leprosy. The availability of a...

Oligonucleotide arrays capable of detecting single nucleotide polymorphisms (SNPs) from amplified nucleic acid have many applications. The expected SNP is usually placed approximately in the center of the probe to ensure the maximum shift in Tm between complementary and SNP sequences. Unfortunately, different short probes (< 30 bases) selected usin...

Tuberculosis (TB) suspects from Rhodes Chest Clinic, Nairobi, Kenya, were subjected to three sputum smear microscopy (Ziehl-Neelsen) examinations and a chest X-ray (CXR). Results were compared with Löwenstein-Jensen culture as the gold standard to establish the efficiency of the routine diagnostic process. All laboratory tests and the CXR were avai...

Over the past decades, the conditions of leprosy control implementation have changed dramatically. Introduction of multidrug therapy, together with the global effort of the World Health Organization to eliminate leprosy as a public health problem, defined as less than one patient per 10.000 inhabitants, had a tremendous impact on leprosy control, p...

The Mycobacterium tuberculosis-specific ESAT-6 antigen induces highly potent T-cell responses and production of gamma interferon (IFN-γ), which play a critical role in protective cell-mediated immunity against tuberculosis (TB). In the present study, IFN-γ secretion by peripheral blood mononuclear cells (PBMCs) in response to M. tuberculosis ESAT-6...

The phenotypic features acquired subsequent to antigen-specific stimulation in vitro were evaluated by means of the kinetic expressions of CD69 and CD25 activation molecules on T lymphocytes and assayed by flow cytometry in response to PPD, Ag85B, and ferritin in PPD-positive healthy control individuals. In response to PHA, CD69 staining on both CD...

The phenotypic features acquired subsequent to antigen-specific stimulation in vitro were evaluated by means of the kinetic expressions of CD69 and CD25 activation molecules on T lymphocytes and assayed by flow cytometry in response to PPD, Ag85B, and ferritin in PPD-positive healthy control individuals. In response to PHA, CD69 staining on both CD...

We conducted a population-based survey on five small islands in South Sulawesi Province (Indonesia) to collect baseline data previous to a chemoprophylactic intervention study aiming at interrupting the transmission of Mycobacterium leprae. Here we describe the present leprosy epidemiology on these geographically isolated islands. Of the 4774 inhab...

Everything that we need to know about Mycobacterium leprae, a close relative of the tubercle bacillus, is encrypted in its genome. Inspection of the 3.27 Mb genome sequence of an armadillo-derived Indian isolate of the leprosy bacillus identified 1,605 genes encoding proteins and 50 genes for stable RNA species. Comparison with the genome sequence...

Classification of leprosy patients into paucibacillary (PB) and multibacillary (MB) determines the duration of treatment; misclassification increases the risk of relapse because of insufficient treatment if an MB patient is classified as PB. We explored the possibility of using a simple dipstick assay based on the detection of antibodies to the Myc...

Leprosy control services face the problem of leprosy patients being misclassified by the lack of or the poor quality of skinsmear examination services. Misclassification increases the risk of relapse due to insufficient treatment if a multibacillary (MB) patient is classified as paucibacillary (PB), thereby also prolonging the time that the patient...

A collaborative study has been undertaken to establish the relationship between infection by Mycobacterium leprae and the development of immunity in a community in which multidrug therapy (MDT) has been used for more than 10 years, to elucidate the pathogenesis of infection in leprosy, and to develop and test an intervention strategy based on chemo...

Over the past decades, the conditions of leprosy control implementation have changed dramatically. Introduction of multidrug therapy, together with the global effort of the World Health Organization to eliminate leprosy as a public health problem, had a tremendous impact on leprosy control, particularly by decreasing the registered prevalence of th...

Neopterin, a low-molecular-mass pteridine produced by macrophages, is closely associated with activation of the cellular immune system. Neopterin biosynthesis during inflammatory disease is primarily derived from interferon-activated monocytes/macrophages and neopterin concentrations may be significantly increased in a particular disease state comp...

In the light of emerging and overlooked infectious diseases and widespread drug resistance, diagnostics have become increasingly important in supporting surveillance, disease control and outbreak management programs. In many low-income countries the diagnostic service has been a neglected part of health care, often lacking quantity and quality or e...

In order to study whether the seroprevalence of antibodies to phenolic glycolipid-I (PGL-I) among school children is a useful indicator of the leprosy problem in certain areas, school surveys were carried out. These surveys have the advantage of targeting an easily accessible, stable and standardized population. Antibodies to the species-specific P...

Antibodies to sulfatide have been reported in various demyelinating peripheral polyneuropathies. We have investigated the diagnostic value of these antibodies in leprosy. Anti-sulfatide IgM in leprosy patients was not significantly elevated. High anti-sulfatide IgG titers were observed in individuals from endemic areas, irrespective of their lepros...

Reactions, a relatively common phenomenon among leprosy patients in treatment, require early detection and proper management to prevent serious sequelae. It is generally accepted that reactional states are immunologically mediated and, as such, usually improve with immunomodulatory treatments such as corticosteroids or thalidomide. Neopterin, a pro...

Notwithstanding the elimination efforts, leprosy control programs face the problem of many leprosy patients remaining undetected. Leprosy control focuses on early diagnosis through screening of household contacts, although this high-risk group generates only a small proportion of all incident cases. For the remaining incident cases, leprosy control...

The presence of mycobacterial antigens in leprosy skin lesions was studied by immunohistological methods using monoclonal antibodies (MAbs) to Mycobacterium leprae-specific phenolic glycolipid I (PGL-I) and to cross-reactive mycobacterial antigens of 36 kd, 65 kd, and lipoarabinomannan (LAM). The staining patterns with MAb to 36 kd and 65 kd were h...